Ritomax-L

Ritomax-L is indicated in combination with other antiretroviral medicinal products for the treatment of human immunodeficiency virus (HIV-1) infected adults, adolescents and children above the age of 2 years.

The choice of Ritomax-L to treat protease inhibitor experienced HIV-1 infected patients should be based on individual viral resistance testing and treatment history of patients.

Kaletra is indicated in combination with other antiretroviral medicinal products for the treatment of human immunodeficiency virus (HIV-1) infected adults, adolescents and children aged from 14 days and older.

The choice of Kaletra to treat protease inhibitor experienced HIV-1 infected patients should be based on individual viral resistance testing and treatment history of patients.

Ritomax-L should be prescribed by physicians who are experienced in the treatment of HIV infection.

Ritomax-L tablets must be swallowed whole and not chewed, broken or crushed.

Posology

Adults and adolescents

Paediatric population (2 years of age and above)

The adult dose of Ritomax-L tablets (400/100 mg twice daily) may be used in children 40 kg or greater or with a Body Surface Area (BSA)* greater than 1.4 m². For children weighing less than 40 kg or with a BSA between 0.5 and 1.4 m² and able to swallow tablets, please refer to the Ritomax-L 100 mg/25 mg tablets Summary of Product Characteristics. For children unable to swallow tablets, please refer to the Ritomax-L oral solution Summary of Product Characteristics. Based on the current data available, Ritomax-L should not be administered once daily in paediatric patients.

* Body surface area can be calculated with the following equation:

BSA (m²) = √ (Height (cm) X Weight (kg) / 3600)

Children less than 2 years of age

Concomitant Therapy: Efavirenz or nevirapine

The following table contains dosing guidelines for Ritomax-L tablets based on BSA when used in combination with efavirenz or nevirapine in children.

* Ritomax-L tablets must not be chewed, broken or crushed.

Hepatic impairment

In HIV-infected patients with mild to moderate hepatic impairment, an increase of approximately 30% in lopinavir exposure has been observed but is not expected to be of clinical relevance. No data are available in patients with severe hepatic impairment. Ritomax-L must not be given to these patients.

Renal impairment

Since the renal clearance of lopinavir and ritonavir is negligible, increased plasma concentrations are not expected in patients with renal impairment. Because lopinavir and ritonavir are highly protein bound, it is unlikely that they will be significantly removed by haemodialysis or peritoneal dialysis.

Pregnancy and postpartum

- No dose adjustment is required for lopinavir/ritonavir during pregnancy and postpartum.

- Once-daily administration of lopinavir/ritonavir is not recommended for pregnant women due to the lack of pharmacokinetic and clinical data.

Method of administration

Ritomax-L tablets are administered orally and must be swallowed whole and not chewed, broken or crushed. Ritomax-L tablets can be taken with or without food.

Kaletra should be prescribed by physicians who are experienced in the treatment of HIV infection.

Posology

Adults and adolescents

The recommended dosage of Kaletra is 5 ml of oral solution (400/100 mg) twice daily taken with food.

Paediatric population aged from 14 days and older

The oral solution formulation is the recommended option for the most accurate dosing in children based on body surface area or body weight. However, if it is judged necessary to resort to solid oral dosage form for children weighing less than 40 kg or with a BSA between 0.5 and 1.4 m² and able to swallow tablets, Kaletra 100 mg/25 mg tablets may be used. The adult dose of Kaletra tablets (400/100 mg twice daily) may be used in children 40 kg or greater or with a Body Surface Area (BSA)* greater than 1.4 m². Kaletra tablets are administered orally and must be swallowed whole and not chewed, broken or crushed. Please refer to the Kaletra 100 mg/25 mg film-coated tablets Summary of Product Characteristics.

Total amounts of alcohol and propylene glycol from all medicines, including Kaletra oral solution, that are to be given to infants should be taken into account in order to avoid toxicity from these excipients.

Dosage recommendation for paediatric patients aged from 14 days to 6 months

*Body surface area can be calculated with the following equation

BSA (m²) = √ (Height (cm) X Weight (kg) / 3600)

It is recommended that Kaletra not be administered in combination with efavirenz or nevirapine in patients less than 6 months of age.

Dosage recommendation for paediatric patients older than 6 months to less than 18 years

Without Concomitant Efavirenz or Nevirapine

The following tables contain dosing guidelines for Kaletra oral solution based on body weight and BSA.

*weight based dosing recommendations are based on limited data

** the volume (ml) of oral solution represents the average dose for the weight range

*Body surface area can be calculated with the following equation

BSA (m²) = √ (Height (cm) X Weight (kg) / 3600)

Concomitant Therapy: Efavirenz or Nevirapine

The 230/57.5 mg/m² dosage might be insufficient in some children when co-administered with nevirapine or efavirenz. An increase of the dose of Kaletra to 300/75 mg/m² is needed in these patients. The recommended dose of 533/133 mg or 6.5 ml twice daily should not be exceeded.

Children less than 14 days of age and premature neonates

Kaletra oral solution should not be administered to neonates before a postmenstrual age (first day of the mother's last menstrual period to birth plus the time elapsed after birth) of 42 weeks and a postnatal age of at least 14 days has been reached.

Hepatic impairment

In HIV-infected patients with mild to moderate hepatic impairment, an increase of approximately 30% in lopinavir exposure has been observed but is not expected to be of clinical relevance. No data are available in patients with severe hepatic impairment. Kaletra must not be given to these patients.

Renal impairment

Since the renal clearance of lopinavir and ritonavir is negligible, increased plasma concentrations are not expected in patients with renal impairment. Because lopinavir and ritonavir are highly protein bound, it is unlikely that they will be significantly removed by haemodialysis or peritoneal dialysis.

Method of administration

Kaletra is administered orally and should always be taken with food. The dose should be administered using a calibrated 2 ml or 5 ml oral dosing syringe best corresponding to the volume prescribed.

Hypersensitivity to the active substances or to any of the excipients.

Severe hepatic insufficiency.

Ritomax-L contains lopinavir and ritonavir, both of which are inhibitors of the P450 isoform CYP3A. Ritomax-L should not be co-administered with medicinal products that are highly dependent on CYP3A for clearance and for which elevated plasma concentrations are associated with serious and/or life threatening events. These medicinal products include:

Hypersensitivity to the active substances or to any of the excipients.

Severe hepatic insufficiency.

Kaletra contains lopinavir and ritonavir, both of which are inhibitors of the P450 isoform CYP3A. Kaletra should not be co-administered with medicinal products that are highly dependent on CYP3A for clearance and for which elevated plasma concentrations are associated with serious and/or life threatening events. These medicinal products include:

Kaletra oral solution is contraindicated in children below the age of 14 days, pregnant women, patients with hepatic or renal failure and patients treated with disulfiram or metronidazole due to the potential risk of toxicity from the excipient propylene glycol.

Patients with coexisting conditions

Hepatic impairment:

The safety and efficacy of Ritomax-L has not been established in patients with significant underlying liver disorders. Ritomax-L is contraindicated in patients with severe liver impairment. Patients with chronic hepatitis B or C and treated with combination antiretroviral therapy are at an increased risk for severe and potentially fatal hepatic adverse reactions. In case of concomitant antiviral therapy for hepatitis B or C, please refer to the relevant product information for these medicinal products.

Patients with pre-existing liver dysfunction including chronic hepatitis have an increased frequency of liver function abnormalities during combination antiretroviral therapy and should be monitored according to standard practice. If there is evidence of worsening liver disease in such patients, interruption or discontinuation of treatment should be considered.

Elevated transaminases with or without elevated bilirubin levels have been reported in HIV-1 mono-infected and in individuals treated for post-exposure prophylaxis as early as 7 days after the initiation of lopinavir/ritonavir in conjunction with other antiretroviral agents. In some cases the hepatic dysfunction was serious.

Appropriate laboratory testing should be conducted prior to initiating therapy with lopinavir/ritonavir and close monitoring should be performed during treatment.

Renal impairment

Since the renal clearance of lopinavir and ritonavir is negligible, increased plasma concentrations are not expected in patients with renal impairment. Because lopinavir and ritonavir are highly protein bound, it is unlikely that they will be significantly removed by haemodialysis or peritoneal dialysis.

Haemophilia

There have been reports of increased bleeding, including spontaneous skin haematomas and haemarthrosis in patients with haemophilia type A and B treated with protease inhibitors. In some patients additional factor VIII was given. In more than half of the reported cases, treatment with protease inhibitors was continued or reintroduced if treatment had been discontinued. A causal relationship had been evoked, although the mechanism of action had not been elucidated. Haemophiliac patients should therefore be made aware of the possibility of increased bleeding.

Pancreatitis

Cases of pancreatitis have been reported in patients receiving Ritomax-L, including those who developed hypertriglyceridaemia. In most of these cases patients have had a prior history of pancreatitis and/or concurrent therapy with other medicinal products associated with pancreatitis. Marked triglyceride elevation is a risk factor for development of pancreatitis. Patients with advanced HIV disease may be at risk of elevated triglycerides and pancreatitis

Pancreatitis should be considered if clinical symptoms (nausea, vomiting, abdominal pain) or abnormalities in laboratory values (such as increased serum lipase or amylase values) suggestive of pancreatitis should occur. Patients who exhibit these signs or symptoms should be evaluated and Ritomax-L therapy should be suspended if a diagnosis of pancreatitis is made.

Immune Reconstitution Inflammatory Syndrome

In HIV-infected patients with severe immune deficiency at the time of institution of combination antiretroviral therapy (CART), an inflammatory reaction to asymtomatic or residual opportunistic pathogens may arise and cause serious clinical conditions, or aggravation of symptoms. Typically, such reactions have been observed within the first few weeks or months of initiation of CART. Relevant examples are cytomegalovirus retinitis, generalised and/or focal mycobacterial infections, and Pneumocystis jiroveci pneumonia. Any inflammatory symptoms should be evaluated and treatment instituted when necessary.

Autoimmune disorders (such as Graves' disease) have also been reported to occur in the setting of immune reconstitution; however, the reported time to onset is more variable and can occur many months after initiation of treatment.

Osteonecrosis

Although the etiology is considered to be multifactorial (including corticosteroid use, alcohol consumption, severe immunosuppression, higher body mass index), cases of osteonecrosis have been reported particularly in patients with advanced HIV-disease and/or long-term exposure to combination antiretroviral therapy (CART). Patients should be advised to seek medical advice if they experience joint aches and pain, joint stiffness or difficulty in movement.

PR interval prolongation

Lopinavir/ritonavir has been shown to cause modest asymptomatic prolongation of the PR interval in some healthy adult subjects. Rare reports of 2^nd or 3^rd degree atroventricular block in patients with underlying structural heart disease and pre-existing conduction system abnormalities or in patients receiving drugs known to prolong the PR interval (such as verapamil or atazanavir) have been reported in patients receiving lopinavir/ritonavir. Ritomax-L should be used with caution in such patients.

Weight and metabolic parameters

An increase in weight and in levels of blood lipids and glucose may occur during antiretroviral therapy. Such changes may in part be linked to disease control and life style. For lipids, there is in some cases evidence for a treatment effect, while for weight gain there is no strong evidence relating this to any particular treatment. For monitoring of blood lipids and glucose, reference is made to established HIV treatment guidelines. Lipid disorders should be managed as clinically appropriate.

Interactions with medicinal products

Ritomax-L contains lopinavir and ritonavir, both of which are inhibitors of the P450 isoform CYP3A. Ritomax-L is likely to increase plasma concentrations of medicinal products that are primarily metabolised by CYP3A. These increases of plasma concentrations of co-administered medicinal products could increase or prolong their therapeutic effect and adverse events.

Life-threatening and fatal drug interactions have been reported in patients treated with colchicine and strong inhibitors of CYP3A like ritonavir. Concomitant administration with colchicine is contraindicated in patients with renal and/or hepatic impairment.

The combination of Ritomax-L with:

- tadalafil, indicated for the treatment of pulmonary arterial hypertension, is not recommended ;

- riociguat is not recommended ;

- vorapaxar is not recommended ;

- fusidic acid in osteo-articular infections is not recommended ;

- salmeterol is not recommended ;

- rivaroxaban is not recommended.

The combination of Ritomax-L with atorvastatin is not recommended. If the use of atorvastatin is considered strictly necessary, the lowest possible dose of atorvastatin should be administered with careful safety monitoring. Caution must also be exercised and reduced doses should be considered if Ritomax-L is used concurrently with rosuvastatin. If treatment with a HMG-CoA reductase inhibitor is indicated, pravastatin or fluvastatin is recommended.

PDE5 inhibitors

Particular caution should be used when prescribing sildenafil or tadalafil for the treatment of erectile dysfunction in patients receiving Ritomax-L. Co-administration of Ritomax-L with these medicinal products is expected to substantially increase their concentrations and may result in associated adverse events such as hypotension, syncope, visual changes and prolonged erection. Concomitant use of avanafil or vardenafil and lopinavir/ritonavir is contraindicated. Concomitant use of sildenafil prescribed for the treatment of pulmonary arterial hypertension with Ritomax-L is contraindicated.

Particular caution must be used when prescribing Ritomax-L and medicinal products known to induce QT interval prolongation such as: chlorpheniramine, quinidine, erythromycin, clarithromycin. Indeed, Ritomax-L could increase concentrations of the co-administered medicinal products and this may result in an increase of their associated cardiac adverse reactions. Cardiac events have been reported with Ritomax-L in preclinical studies; therefore, the potential cardiac effects of Ritomax-L cannot be currently ruled out.

Co-administration of Ritomax-L with rifampicin is not recommended. Rifampicin in combination with Ritomax-L causes large decreases in lopinavir concentrations which may in turn significantly decrease the lopinavir therapeutic effect. Adequate exposure to lopinavir/ritonavir may be achieved when a higher dose of Ritomax-L is used but this is associated with a higher risk of liver and gastrointestinal toxicity. Therefore, this co-administration should be avoided unless judged strictly necessary.

Concomitant use of Ritomax-L and fluticasone or other glucocorticoids that are metabolised by CYP3A4, such as budesonide and triamcinolone, is not recommended unless the potential benefit of treatment outweighs the risk of systemic corticosteroid effects, including Cushing's syndrome and adrenal suppression.

Other

Ritomax-L is not a cure for HIV infection or AIDS. While effective viral suppression with antiretroviral therapy has been proven to substantially reduce the risk of sexual transmission, a residual risk cannot be excluded. Precautions to prevent transmission should be taken in accordance with national guidelines. People taking Ritomax-L may still develop infections or other illnesses associated with HIV disease and AIDS.

Patients with coexisting conditions

Hepatic impairment

The safety and efficacy of Kaletra has not been established in patients with significant underlying liver disorders. Kaletra is contraindicated in patients with severe liver impairment. Patients with chronic hepatitis B or C and treated with combination antiretroviral therapy are at an increased risk for severe and potentially fatal hepatic adverse reactions. In case of concomitant antiviral therapy for hepatitis B or C, please refer to the relevant product information for these medicinal products.

Patients with pre-existing liver dysfunction including chronic hepatitis have an increased frequency of liver function abnormalities during combination antiretroviral therapy and should be monitored according to standard practice. If there is evidence of worsening liver disease in such patients, interruption or discontinuation of treatment should be considered.

Elevated transaminases with or without elevated bilirubin levels have been reported in HIV-1 mono-infected and in individuals treated for post-exposure prophylaxis as early as 7 days after the initiation of lopinavir/ritonavir in conjunction with other antiretroviral agents. In some cases the hepatic dysfunction was serious.

Appropriate laboratory testing should be conducted prior to initiating therapy with lopinavir/ritonavir and close monitoring should be performed during treatment.

Renal impairment

Since the renal clearance of lopinavir and ritonavir is negligible, increased plasma concentrations are not expected in patients with renal impairment. Because lopinavir and ritonavir are highly protein bound, it is unlikely that they will be significantly removed by haemodialysis or peritoneal dialysis.

Haemophilia

There have been reports of increased bleeding, including spontaneous skin haematomas and haemarthrosis in patients with haemophilia type A and B treated with protease inhibitors. In some patients additional factor VIII was given. In more than half of the reported cases, treatment with protease inhibitors was continued or reintroduced if treatment had been discontinued. A causal relationship had been evoked, although the mechanism of action had not been elucidated. Haemophiliac patients should therefore be made aware of the possibility of increased bleeding.

Pancreatitis

Cases of pancreatitis have been reported in patients receiving Kaletra, including those who developed hypertriglyceridaemia. In most of these cases patients have had a prior history of pancreatitis and/or concurrent therapy with other medicinal products associated with pancreatitis. Marked triglyceride elevation is a risk factor for development of pancreatitis. Patients with advanced HIV disease may be at risk of elevated triglycerides and pancreatitis.

Pancreatitis should be considered if clinical symptoms (nausea, vomiting, abdominal pain) or abnormalities in laboratory values (such as increased serum lipase or amylase values) suggestive of pancreatitis should occur. Patients who exhibit these signs or symptoms should be evaluated and Kaletra therapy should be suspended if a diagnosis of pancreatitis is made.

Immune Reconstitution Inflammatory Syndrome

In HIV-infected patients with severe immune deficiency at the time of institution of combination antiretroviral therapy (CART), an inflammatory reaction to asymtomatic or residual opportunistic pathogens may arise and cause serious clinical conditions, or aggravation of symptoms. Typically, such reactions have been observed within the first few weeks or months of initiation of CART. Relevant examples are cytomegalovirus retinitis, generalised and/or focal mycobacterial infections, and Pneumocystis jiroveci pneumonia. Any inflammatory symptoms should be evaluated and treatment instituted when necessary.

Autoimmune disorders (such as Graves' disease) have also been reported to occur in the setting of immune reconstitution; however, the reported time to onset is more variable and can occur many months after initiation of treatment.

Osteonecrosis

Although the etiology is considered to be multifactorial (including corticosteroid use, alcohol consumption, severe immunosuppression, higher body mass index), cases of osteonecrosis have been reported particularly in patients with advanced HIV-disease and/or long-term exposure to combination antiretroviral therapy (CART). Patients should be advised to seek medical advice if they experience joint aches and pain, joint stiffness or difficulty in movement.

PR interval prolongation

Lopinavir/ritonavir has been shown to cause modest asymptomatic prolongation of the PR interval in some healthy adult subjects. Rare reports of 2^nd or 3^rd degree atroventricular block in patients with underlying structural heart disease and pre-existing conduction system abnormalities or in patients receiving drugs known to prolong the PR interval (such as verapamil or atazanavir) have been reported in patients receiving lopinavir/ritonavir. Kaletra should be used with caution in such patients.

Weight and metabolic parameters

An increase in weight and in levels of blood lipids and glucose may occur during antiretroviral therapy. Such changes may in part be linked to disease control and life style. For lipids, there is in some cases evidence for a treatment effect, while for weight gain there is no strong evidence relating this to any particular treatment. For monitoring of blood lipids and glucose, reference is made to established HIV treatment guidelines. Lipid disorders should be managed as clinically appropriate.

Interactions with medicinal products

Kaletra contains lopinavir and ritonavir, both of which are inhibitors of the P450 isoform CYP3A. Kaletra is likely to increase plasma concentrations of medicinal products that are primarily metabolised by CYP3A. These increases of plasma concentrations of co-administered medicinal products could increase or prolong their therapeutic effect and adverse events.

Life-threatening and fatal drug interactions have been reported in patients treated with colchicine and strong inhibitors of CYP3A like ritonavir. Concomitant administration with colchicine is contraindicated in patients with renal and/or hepatic impairment.

The combination of Kaletra with:

- tadalafil, indicated for the treatment of pulmonary arterial hypertension, is not recommended ;

- riociguat is not recommended ;

- vorapaxar is not recommended ;

- fusidic acid in osteo-articular infections is not recommended ;

- salmeterol is not recommended ;

- rivaroxaban is not recommended.

The combination of Kaletra with atorvastatin is not recommended. If the use of atorvastatin is considered strictly necessary, the lowest possible dose of atorvastatin should be administered with careful safety monitoring. Caution must also be exercised and reduced doses should be considered if Kaletra is used concurrently with rosuvastatin. If treatment with an HMG-CoA reductase inhibitor is indicated, pravastatin or fluvastatin is recommended.

PDE5 inhibitors

Particular caution should be used when prescribing sildenafil or tadalafil for the treatment of erectile dysfunction in patients receiving Kaletra. Co-administration of Kaletra with these medicinal products is expected to substantially increase their concentrations and may result in associated adverse events such as hypotension, syncope, visual changes and prolonged erection. Concomitant use of avanafil or vardenafil and lopinavir/ritonavir is contraindicated. Concomitant use of sildenafil prescribed for the treatment of pulmonary arterial hypertension with Kaletra is contraindicated.

Particular caution must be used when prescribing Kaletra and medicinal products known to induce QT interval prolongation such as: chlorpheniramine, quinidine, erythromycin, clarithromycin. Indeed, Kaletra could increase concentrations of the co-administered medicinal products and this may result in an increase of their associated cardiac adverse reactions. Cardiac events have been reported with Kaletra in preclinical studies; therefore, the potential cardiac effects of Kaletra cannot be currently ruled out.

Co-administration of Kaletra with rifampicin is not recommended. Rifampicin in combination with Kaletra causes large decreases in lopinavir concentrations which may in turn significantly decrease the lopinavir therapeutic effect. Adequate exposure to lopinavir/ritonavir may be achieved when a higher dose of Kaletra is used but this is associated with a higher risk of liver and gastrointestinal toxicity. Therefore, this co-administration should be avoided unless judged strictly necessary.

Concomitant use of Kaletra and fluticasone or other glucocorticoids that are metabolised by CYP3A4, such as budesonide and triamcinolone, is not recommended unless the potential benefit of treatment outweighs the risk of systemic corticosteroid effects, including Cushing's syndrome and adrenal suppression.

Other

Patients taking the oral solution, particularly those with renal impairment or with decreased ability to metabolise propylene glycol (e.g. those of Asian origin), should be monitored for adverse reactions potentially related to propylene glycol toxicity (i.e. seizures, stupor, tachycardia, hyperosmolarity, lactic acidosis, renal toxicity, haemolysis).

Kaletra is not a cure for HIV infection or AIDS. While effective viral suppression with antiretroviral therapy has been proven to substantially reduce the risk of sexual transmission, a residual risk cannot be excluded. Precautions to prevent transmission should be taken in accordance with national guidelines. People taking Kaletra may still develop infections or other illnesses associated with HIV disease and AIDS.

Besides propylene glycol as described above, Kaletra oral solution contains alcohol (42% v/v) which is potentially harmful for those suffering from liver disease, alcoholism, epilepsy, brain injury or disease as well as for pregnant women and children. It may modify or increase the effects of other medicines. Kaletra oral solution contains up to 0.8 g of fructose per dose when taken according to the dosage recommendations. This may be unsuitable in hereditary fructose intolerance. Kaletra oral solution contains up to 0.3 g of glycerol per dose. Only at high inadvertent doses, it can cause headache and gastrointestinal upset. Furthermore, polyoxol 40 hydrogenated castor oil and potassium present in Kaletra oral solution may cause only at high inadvertent doses gastrointestinal upset. Patients on a low potassium diet should be cautioned.

Particular risk of toxicity in relation to the amount of alcohol and propylene glycol contained in Kaletra oral solution

Healthcare professionals should be aware that Kaletra oral solution is highly concentrated and contains 42.4% alcohol (v/v) and 15.3% propylene glycol (w/v). Each 1 ml of Kaletra oral solution contains 356.3 mg of alcohol and 152.7 mg of propylene glycol.

Special attention should be given to accurate calculation of the dose of Kaletra, transcription of the medication order, dispensing information and dosing instructions to minimize the risk for medication errors and overdose. This is especially important for infants and young children.

Total amounts of alcohol and propylene glycol from all medicines that are to be given to infants should be taken into account in order to avoid toxicity from these excipients. Infants should be monitored closely for toxicity related to Kaletra oral solution including: hyperosmolality, with or without lactic acidosis, renal toxicity, central nervous system (CNS) depression (including stupor, coma, and apnea), seizures, hypotonia, cardiac arrhythmias and ECG changes, and hemolysis. Postmarketing life-threatening cases of cardiac toxicity (including complete atrioventricular (AV) block, bradycardia, and cardiomyopathy), lactic acidosis, acute renal failure, CNS depression and respiratory complications leading to death have been reported, predominantly in preterm neonates receiving Kaletra oral solution.

Based on the findings in a paediatric study (observed exposures were approximately 35% AUC₁₂ and 75% lower C_min than in adults), young children from 14 days to 3 months could have sub-optimal exposure with a potential risk of inadequate virologic suppression and emergence of resistance.

Because Kaletra oral solution contains alcohol, it is not recommended for use with polyurethane feeding tubes due to potential incompatibility.

No studies on the effects on the ability to drive and use machines have been performed. Patients should be informed that nausea has been reported during treatment with Ritomax-L.

No studies on the effects on the ability to drive and use machines have been performed. Patients should be informed that nausea has been reported during treatment with Kaletra.

Kaletra oral solution contains approximately 42% v/v alcohol.

a. Summary of the safety profile

The safety of Ritomax-L has been investigated in over 2600 patients in Phase II-IV clinical trials, of which over 700 have received a dose of 800/200 mg (6 capsules or 4 tablets) once daily. Along with nucleoside reverse transcriptase inhibitors (NRTIs), in some studies, Ritomax-L was used in combination with efavirenz or nevirapine.

The most common adverse reactions related to Ritomax-L therapy during clinical trials were diarrhoea, nausea, vomiting, hypertriglyceridaemia and hypercholesterolemia. The risk of diarrhoea may be greater with once-daily dosing of Ritomax-L. Diarrhoea, nausea and vomiting may occur at the beginning of the treatment while hypertriglyceridaemia and hypercholesterolemia may occur later. Treatment emergent adverse events led to premature study discontinuation for 7% of subjects from Phase II-IV studies.

It is important to note that cases of pancreatitis have been reported in patients receiving Ritomax-L, including those who developed hypertriglyceridaemia. Furthermore, rare increases in PR interval have been reported during Ritomax-L therapy.

b. Tabulated list of adverse reactions

Adverse reactions from clinical trials and post-marketing experience in adult and paediatric patients:

The following events have been identified as adverse reactions. The frequency category includes all reported events of moderate to severe intensity, regardless of the individual causality assessment. The adverse reactions are displayed by system organ class. Within each frequency grouping, undesirable effects are presented in order of decreasing seriousness: very common (> 1/10), common (> 1/100 to < 1/10), uncommon (> 1/1000 to < 1/100) and not known (cannot be estimated from the available data).

Events noted as having frequency “Not known” were identified via post-marketing surveillance.

<: pancreatitis and lipids

c. Description of selected adverse reactions

Cushing's syndrome has been reported in patients receiving ritonavir and inhaled or intranasally administered fluticasone propionate; this could also occur with other corticosteroids metabolised via the P450 3A pathway e.g. budesonide.

Increased creatine phosphokinase (CPK), myalgia, myositis, and rarely, rhabdomyolysis have been reported with protease inhibitors, particularly in combination with nucleoside reverse transcriptase inhibitors.

Metabolic parameters

Weight and levels of blood lipids and glucose may increase during antiretroviral therapy.

In HIV-infected patients with severe immune deficiency at the time of initiation of combination antiretroviral therapy (CART), an inflammatory reaction to asymptomatic or residual opportunistic infections may arise. Autoimmune disorders (such as Graves' disease) have also been reported; however, the reported time to onset is more variable and can occur many months after initiation of treatment.

Cases of osteonecrosis have been reported, particularly in patients with generally acknowledged risk factors, advanced HIV disease or long-term exposure to combination antiretroviral therapy (CART). The frequency of this is unknown.

d. Paediatric populations

In children 2 years of age and older, the nature of the safety profile is similar to that seen in adults (see Table in section b).

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme:

Website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store

a. Summary of the safety profile

The safety of Kaletra has been investigated in over 2600 patients in Phase II-IV clinical trials, of which over 700 have received a dose of 800/200 mg (6 capsules or 4 tablets) once daily. Along with nucleoside reverse transcriptase inhibitors (NRTIs), in some studies, Kaletra was used in combination with efavirenz or nevirapine.

The most common adverse reactions related to Kaletra therapy during clinical trials were diarrhoea, nausea, vomiting, hypertriglyceridaemia and hypercholesterolemia. Diarrhoea, nausea and vomiting may occur at the beginning of the treatment while hypertriglyceridaemia and hypercholesterolemia may occur later. Treatment emergent adverse events led to premature study discontinuation for 7% of subjects from Phase II-IV studies.

It is important to note that cases of pancreatitis have been reported in patients receiving Kaletra, including those who developed hypertriglyceridaemia. Furthermore, rare increases in PR interval have been reported during Kaletra therapy.

b. Tabulated list of adverse reactions

Adverse reactions from clinical trials and post-marketing experience in adult and paediatric patients:

The following events have been identified as adverse reactions. The frequency category includes all reported events of moderate to severe intensity, regardless of the individual causality assessment. The adverse reactions are displayed by system organ class. Within each frequency grouping, undesirable effects are presented in order of decreasing seriousness: very common (>1/10), common (> 1/100 to < 1/10), uncommon (> 1/1000 to < 1/100) and not known (cannot be estimated from the available data).

Events noted as having frequency “Not known” were identified via post-marketing surveillance.

<: pancreatitis and lipids

c. Description of selected adverse reactions

Cushing's syndrome has been reported in patients receiving ritonavir and inhaled or intranasally administered fluticasone propionate; this could also occur with other corticosteroids metabolised via the P450 3A pathway e.g. budesonide.

Increased creatine phosphokinase (CPK), myalgia, myositis, and rarely, rhabdomyolysis have been reported with protease inhibitors, particularly in combination with nucleoside reverse transcriptase inhibitors.

Metabolic parameters

Weight and levels of blood lipids and glucose may increase during antiretroviral therapy.

In HIV-infected patients with severe immune deficiency at the time of initiation of combination antiretroviral therapy (CART), an inflammatory reaction to asymptomatic or residual opportunistic infections may arise. Autoimmune disorders (such as Graves' disease) have also been reported; however, the reported time to onset is more variable and can occur many months after initiation of treatment.

Cases of osteonecrosis have been reported, particularly in patients with generally acknowledged risk factors, advanced HIV disease or long-term exposure to combination antiretroviral therapy (CART). The frequency of this is unknown.

d. Paediatric populations

In children 14 days of age and older, the nature of the safety profile is similar to that seen in adults (see Table in section b).

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme:

Website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

To date, there is limited human experience of acute overdose with Ritomax-L.

The adverse clinical signs observed in dogs included salivation, emesis and diarrhoea/abnormal stool. The signs of toxicity observed in mice, rats or dogs included decreased activity, ataxia, emaciation, dehydration and tremors.

There is no specific antidote for overdose with Ritomax-L. Treatment of overdose with Ritomax-L is to consist of general supportive measures including monitoring of vital signs and observation of the clinical status of the patient. If indicated, elimination of unabsorbed active substance is to be achieved by emesis or gastric lavage. Administration of activated charcoal may also be used to aid in removal of unabsorbed active substance. Since Ritomax-L is highly protein bound, dialysis is unlikely to be beneficial in significant removal of the active substance.

To date, there is limited human experience of acute overdose with Kaletra.

Overdoses with Kaletra oral solution have been reported (including fatal outcome). The following events have been reported in association with unintended overdoses in preterm neonates: complete atrioventricular block, cardiomyopathy, lactic acidosis, and acute renal failure.

The adverse clinical signs observed in dogs included salivation, emesis and diarrhoea/abnormal stool. The signs of toxicity observed in mice, rats or dogs included decreased activity, ataxia, emaciation, dehydration and tremors.

There is no specific antidote for overdose with Kaletra. Treatment of overdose with Kaletra is to consist of general supportive measures including monitoring of vital signs and observation of the clinical status of the patient. If indicated, elimination of unabsorbed active substance is to be achieved by emesis or gastric lavage. Administration of activated charcoal may also be used to aid in removal of unabsorbed active substance. Since Kaletra is highly protein bound, dialysis is unlikely to be beneficial in significant removal of the active substance.

However, dialysis can remove both alcohol and propylene glycol in the case of overdose with Kaletra oral solution.

Pharmaco-therapeutic group: antivirals for systemic use, antivirals for treatment of HIV infections, combinations, ATC code: J05AR10

Mechanism of action

Lopinavir provides the antiviral activity of Ritomax-L. Lopinavir is an inhibitor of the HIV-1 and HIV-2 proteases. Inhibition of HIV protease prevents cleavage of the gag-pol polyprotein resulting in the production of immature, non-infectious virus.

Effects on the electrocardiogram

QTcF interval was evaluated in a randomised, placebo and active (moxifloxacin 400 mg once daily) controlled crossover study in 39 healthy adults, with 10 measurements over 12 hours on Day 3. The maximum mean (95% upper confidence bound) differences in QTcF from placebo were 3.6 (6.3) and 13.1(15.8) for 400/100 mg twice daily and supratherapeutic 800/200 mg twice daily LPV/r, respectively. The induced QRS interval prolongation from 6 ms to 9.5 ms with high dose lopinavir/ritonavir (800/200 mg twice daily) contributes to QT prolongation. The two regimens resulted in exposures on Day 3 which were approximately 1.5 and 3-fold higher than those observed with recommended once-daily or twice-daily LPV/r doses at steady state. No subject experienced an increase in QTcF of > 60 ms from baseline or a QTcF interval exceeding the potentially clinically relevant threshold of 500 ms.

Modest prolongation of the PR interval was also noted in subjects receiving lopinavir/ritonavir in the same study on Day 3. The mean changes from baseline in PR interval ranged from 11.6 ms to 24.4 ms in the 12 hour interval post dose. Maximum PR interval was 286 ms and no second or third degree heart block was observed.

Antiviral activity in vitro

The in vitro antiviral activity of lopinavir against laboratory and clinical HIV strains was evaluated in acutely infected lymphoblastic cell lines and peripheral blood lymphocytes, respectively. In the absence of human serum, the mean IC₅₀ of lopinavir against five different HIV-1 laboratory strains was 19 nM. In the absence and presence of 50% human serum, the mean IC₅₀ of lopinavir against HIV-1_IIIB in MT4 cells was 17 nM and 102 nM, respectively. In the absence of human serum, the mean IC₅₀ of lopinavir was 6.5 nM against several HIV-1 clinical isolates.

Resistance

In vitro selection of resistance

HIV-1 isolates with reduced susceptibility to lopinavir have been selected in vitro. HIV-1 has been passaged in vitro with lopinavir alone and with lopinavir plus ritonavir at concentration ratios representing the range of plasma concentration ratios observed during Ritomax-L therapy. Genotypic and phenotypic analysis of viruses selected in these passages suggest that the presence of ritonavir, at these concentration ratios, does not measurably influence the selection of lopinavir-resistant viruses. Overall, the in vitro characterisation of phenotypic cross-resistance between lopinavir and other protease inhibitors suggest that decreased susceptibility to lopinavir correlated closely with decreased susceptibility to ritonavir and indinavir, but did not correlate closely with decreased susceptibility to amprenavir, saquinavir, and nelfinavir.

Analysis of resistance in ARV-naïve patients

In clinical studies with a limited number of isolates analysed, the selection of resistance to lopinavir has not been observed in naïve patients without significant protease inhibitor resistance at baseline. See further the detailed description of the clinical studies.

Analysis of resistance in PI-experienced patients

The selection of resistance to lopinavir in patients having failed prior protease inhibitor therapy was characterised by analysing the longitudinal isolates from 19 protease inhibitor-experienced subjects in 2 Phase II and one Phase III studies who either experienced incomplete virologic suppression or viral rebound subsequent to initial response to Ritomax-L and who demonstrated incremental in vitro resistance between baseline and rebound (defined as emergence of new mutations or 2-fold change in phenotypic susceptibility to lopinavir). Incremental resistance was most common in subjects whose baseline isolates had several protease inhibitor-associated mutations, but < 40-fold reduced susceptibility to lopinavir at baseline. Mutations V82A, I54V and M46I emerged most frequently. Mutations L33F, I50V and V32I combined with I47V/A were also observed. The 19 isolates demonstrated a 4.3-fold increase in IC₅₀ compared to baseline isolates (from 6.2- to 43-fold, compared to wild-type virus).

Genotypic correlates of reduced phenotypic susceptibility to lopinavir in viruses selected by other protease inhibitors. The in vitro antiviral activity of lopinavir against 112 clinical isolates taken from patients failing therapy with one or more protease inhibitors was assessed. Within this panel, the following mutations in HIV protease were associated with reduced in vitro susceptibility to lopinavir: L10F/I/R/V, K20M/R, L24I, M46I/L, F53L, I54L/T/V, L63P, A71I/L/T/V, V82A/F/T, I84V and L90M. The median EC₅₀ of lopinavir against isolates with 0 − 3, 4 − 5, 6 − 7 and 8 − 10 mutations at the above amino acid positions was 0.8, 2.7 13.5 and 44.0-fold higher than the EC₅₀ against wild type HIV, respectively. The 16 viruses that displayed > 20-fold change in susceptibility all contained mutations at positions 10, 54, 63 plus 82 and/or 84. In addition, they contained a median of 3 mutations at amino acid positions 20, 24, 46, 53, 71 and 90. In addition to the mutations described above, mutations V32I and I47A have been observed in rebound isolates with reduced lopinavir susceptibility from protease inhibitor experienced patients receiving Ritomax-L therapy, and mutations I47A and L76V have been observed in rebound isolates with reduced lopinavir susceptibility from patients receiving Ritomax-L therapy.

Conclusions regarding the relevance of particular mutations or mutational patterns are subject to change with additional data, and it is recommended to always consult current interpretation systems for analysing resistance test results.

Antiviral activity of Ritomax-L in patients failing protease inhibitor therapy

The clinical relevance of reduced in vitro susceptibility to lopinavir has been examined by assessing the virologic response to Ritomax-L therapy, with respect to baseline viral genotype and phenotype, in 56 patients previous failing therapy with multiple protease inhibitors. The EC₅₀ of lopinavir against the 56 baseline viral isolates ranged from 0.6 to 96-fold higher than the EC₅₀ against wild type HIV. After 48 weeks of treatment with Ritomax-L, efavirenz and nucleoside reverse transcriptase inhibitors, plasma HIV RNA ≤ 400 copies/ml was observed in 93% (25/27), 73% (11/15), and 25% (2/8) of patients with < 10-fold, 10 to 40-fold, and > 40-fold reduced susceptibility to lopinavir at baseline, respectively. In addition, virologic response was observed in 91% (21/23), 71% (15/21) and 33% (2/6) patients with 0 − 5, 6 − 7, and 8 − 10 mutations of the above mutations in HIV protease associated with reduced in vitro susceptibility to lopinavir. Since these patients had not previously been exposed to either Ritomax-L or efavirenz, part of the response may be attributed to the antiviral activity of efavirenz, particularly in patients harbouring highly lopinavir resistant virus. The study did not contain a control arm of patients not receiving Ritomax-L.

Cross-resistance

Activity of other protease inhibitors against isolates that developed incremental resistance to lopinavir after Ritomax-L therapy in protease inhibitor experienced patients: The presence of cross resistance to other protease inhibitors was analysed in 18 rebound isolates that had demonstrated evolution of resistance to lopinavir during 3 Phase II and one Phase III studies of Ritomax-L in protease inhibitor-experienced patients. The median fold IC₅₀ of lopinavir for these 18 isolates at baseline and rebound was 6.9- and 63-fold, respectively, compared to wild type virus. In general, rebound isolates either retained (if cross-resistant at baseline) or developed significant cross-resistance to indinavir, saquinavir and atazanavir. Modest decreases in amprenavir activity were noted with a median increase of IC₅₀ from 3.7- to 8-fold in the baseline and rebound isolates, respectively. Isolates retained susceptibility to tipranavir with a median increase of IC₅₀ in baseline and rebound isolates of 1.9- and 1.8-fold, respectively, compared to wild type virus. Please refer to the Aptivus Summary of Product Characteristics for additional information on the use of tipranavir, including genotypic predictors of response, in treatment of lopinavir-resistant HIV-1 infection.

Clinical results

The effects of Ritomax-L (in combination with other antiretroviral agents) on biological markers (plasma HIV RNA levels and CD4+ T-cell counts) have been investigated in controlled studies of Ritomax-L of 48 to 360 weeks duration.

Adult Use

Patients without prior antiretroviral therapy

Study M98-863 was a randomised, double-blind trial of 653 antiretroviral treatment naïve patients investigating Ritomax-L (400/100 mg twice daily) compared to nelfinavir (750 mg three times daily) plus stavudine and lamivudine. Mean baseline CD4+ T-cell count was 259 cells/mm³ (range: 2 to 949 cells/ mm³) and mean baseline plasma HIV-1 RNA was 4.9 log₁₀ copies/ml (range: 2.6 to 6.8 log₁₀ copies/ml).

Table 1

* intent to treat analysis where patients with missing values are considered virologic failures

†p < 0.001

One-hundred thirteen nelfinavir-treated patients and 74 lopinavir/ritonavir-treated patients had an HIV RNA above 400 copies/ml while on treatment from Week 24 through Week 96. Of these, isolates from 96 nelfinavir-treated patients and 51 lopinavir/ritonavir-treated patients could be amplified for resistance testing. Resistance to nelfinavir, defined as the presence of the D30N or L90M mutation in protease, was observed in 41/96 (43%) patients. Resistance to lopinavir, defined as the presence of any primary or active site mutations in protease (see above), was observed in 0/51 (0%) patients. Lack of resistance to lopinavir was confirmed by phenotypic analysis.

Study M05-730 was a randomised, open-label, multicentre trial comparing treatment with Ritomax-L 800/200 mg once daily plus tenofovir DF and emtricitabine versus Ritomax-L 400/100 mg twice daily plus tenofovir DF and emtricitabine in 664 antiretroviral treatment-naïve patients. Given the pharmacokinetic interaction between Ritomax-L and tenofovir , the results of this study might not be strictly extrapolable when other backbone regimens are used with Ritomax-L. Patients were randomised in a 1:1 ratio to receive either Ritomax-L 800/200 mg once daily (n = 333) or Ritomax-L 400/100 mg twice daily (n = 331). Further stratification within each group was 1:1 (tablet versus soft capsule). Patients were administered either the tablet or the soft capsule formulation for 8 weeks, after which all patients were administered the tablet formulation once daily or twice daily for the remainder of the study. Patients were administered emtricitabine 200 mg once daily and tenofovir DF 300 mg once daily. Protocol defined non-inferiority of once-daily dosing compared with twice-daily dosing was demonstrated if the lower bound of the 95% confidence interval for the difference in proportion of subjects responding (once daily minus twice daily) excluded -12% at Week 48. Mean age of patients enrolled was 39 years (range: 19 to 71); 75% were Caucasian, and 78% were male. Mean baseline CD4+ T-cell count was 216 cells/mm3 (range: 20 to 775 cells/mm³) and mean baseline plasma HIV-1 RNA was 5.0 log₁₀ copies/ml (range: 1.7 to 7.0 log₁₀ copies/ml).

Table 2

Through Week 96, genotypic resistance testing results were available from 25 patients in the QD group and 26 patients in the BID group who had incomplete virologic response. In the QD group, no patient demonstrated lopinavir resistance, and in the BID group, 1 patient who had significant protease inhibitor resistance at baseline demonstrated additional lopinavir resistance on study.

Sustained virological response to Ritomax-L (in combination with nucleoside/nucleotide reverse transcriptase inhibitors) has been also observed in a small Phase II study (M97-720) through 360 weeks of treatment. One hundred patients were originally treated with Ritomax-L in the study (including 51 patients receiving 400/100 mg twice daily and 49 patients at either 200/100 mg twice daily or 400/200 mg twice daily). All patients converted to open-label Ritomax-L at the 400/100 mg twice-daily dose between week 48 and week 72. Thirty-nine patients (39%) discontinued the study, including 16 (16%) discontinuations due to adverse events, one of which was associated with a death. Sixty-one patients completed the study (35 patients received the recommended 400/100 mg twice-daily dose throughout the study).

Table 3

Through 360 weeks of treatment, genotypic analysis of viral isolates was successfully conducted in 19 of 28 patients with confirmed HIV RNA above 400 copies/ml revealed no primary or active site mutations in protease (amino acids at positions 8, 30, 32, 46, 47, 48, 50, 82, 84 and 90) or protease inhibitor phenotypic resistance.

Patients with prior antiretroviral therapy

M06-802 was a randomised open-label study comparing the safety, tolerability and antiviral activity of once-daily and twice-daily dosing of lopinavir/ritonavir tablets in 599 subjects with detectable viral loads while receiving their current antiviral therapy. Patients had not been on prior lopinavir/ritonavir therapy. They were randomised in a 1:1 ratio to receive either lopinavir/ritonavir 800/200 mg once daily (n = 300) or lopinavir/ritonavir 400/100 mg twice daily (n = 299). Patients were administered at least two nucleoside/nucleotide reverse transcriptase inhibitors selected by the investigator. The enrolled population was moderately PI-experienced with more than half of patients having never received prior PI and around 80% of patients presenting a viral strain with less than 3 PI mutations. Mean age of patients enrolled was 41 years (range: 21 to 73); 51% were Caucasian and 66% were male. Mean baseline CD4+ T-cell count was 254 cells/mm³ (range: 4 to 952 cells/mm³) and mean baseline plasma HIV-1 RNA was 4.3 log₁₀ copies/ml (range: 1.7 to 6.6 log₁₀ copies/ml). Around 85% of patients had a viral load of < 100,000 copies/ml.

Table 4

Through Week 48, genotypic resistance testing results were available from 75 patients in the QD group and 75 patients in the BID group who had incomplete virologic response. In the QD group, 6/75 (8%) patients demonstrated new primary protease inhibitor mutations (codons 30, 32, 48, 50, 82, 84, 90), as did 12/77 (16%) patients in the BID group.

Paediatric Use

M98-940 was an open-label study of a liquid formulation of Ritomax-L in 100 antiretroviral naïve (44%) and experienced (56%) paediatric patients. All patients were non-nucleoside reverse transcriptase inhibitor naïve. Patients were randomised to either 230 mg lopinavir/57.5 mg ritonavir per m² or 300 mg lopinavir/75 mg ritonavir per m². Naïve patients also received nucleoside reverse transcriptase inhibitors. Experienced patients received nevirapine plus up to two nucleoside reverse transcriptase inhibitors. Safety, efficacy and pharmacokinetic profiles of the two dose regimens were assessed after 3 weeks of therapy in each patient. Subsequently, all patients were continued on the 300/75 mg per m² dose. Patients had a mean age of 5 years (range 6 months to 12 years) with 14 patients less than 2 years old and 6 patients one year or less. Mean baseline CD4+ T-cell count was 838 cells/mm³ and mean baseline plasma HIV-1 RNA was 4.7 log₁₀ copies/ml.

Table 5

KONCERT/PENTA 18 is a prospective multicentre, randomised, open-label study that evaluated the pharmacokinetic profile, efficacy and safety of twice-daily versus once-daily dosing of lopinavir/ritonavir 100 mg/25 mg tablets dosed by weight as part of combination antiretroviral therapy (cART) in virologically suppressed HIV-1 infected children (n=173). Children were eligible when they were aged <18 years, >15 kg in weight, receiving cART that included lopinavir/ritonavir, HIV-1 ribonucleic acid (RNA) <50 copies/ml for at least 24 weeks and able to swallow tablets. At week 48, the efficacy and safety with twice-daily dosing (n=87) in the paediatric population given lopinavir/ritonavir 100 mg/25 mg tablets was consistent with the efficacy and safety findings in previous adult and paediatric studies using lopinavir/ritonavir twice daily. The percentage of patients with confirmed viral rebound >50 copies/ml during 48 weeks of follow-up was higher in the paediatric patients receiving lopinavir/ritonavir tablets once daily (12%) than in patients receiving the twice-daily dosing (8%, p = 0.19), mainly due to lower adherence in the once-daily group. The efficacy data favouring the twice-daily regimen are reinforced by a differential in pharmacokinetic parameters significantly favouring the twice-daily regimen.

Pharmaco-therapeutic group: antivirals for systemic use, antivirals for treatment of HIV infections, combinations, ATC code: J05AR10

Mechanism of action

Lopinavir provides the antiviral activity of Kaletra. Lopinavir is an inhibitor of the HIV-1 and HIV-2 proteases. Inhibition of HIV protease prevents cleavage of the gag-pol polyprotein resulting in the production of immature, non-infectious virus.

Effects on the electrocardiogram

QTcF interval was evaluated in a randomised, placebo and active (moxifloxacin 400 mg once daily) controlled crossover study in 39 healthy adults, with 10 measurements over 12 hours on Day 3. The maximum mean (95% upper confidence bound) differences in QTcF from placebo were 3.6 (6.3) and 13.1(15.8) for 400/100 mg twice daily and supratherapeutic 800/200 mg twice daily LPV/r, respectively. The induced QRS interval prolongation from 6 ms to 9.5 ms with high dose lopinavir/ritonavir (800/200 mg twice daily) contributes to QT prolongation. The two regimens resulted in exposures on Day 3 which were approximately 1.5 and 3-fold higher than those observed with recommended once daily or twice daily LPV/r doses at steady state. No subject experienced an increase in QTcF of > 60 ms from baseline or a QTcF interval exceeding the potentially clinically relevant threshold of 500 ms.

Modest prolongation of the PR interval was also noted in subjects receiving lopinavir/ritonavir in the same study on Day 3. The mean changes from baseline in PR interval ranged from 11.6 ms to 24.4 ms in the 12 hour interval post dose. Maximum PR interval was 286 ms and no second or third degree heart block was observed.

Antiviral activity in vitro

The in vitro antiviral activity of lopinavir against laboratory and clinical HIV strains was evaluated in acutely infected lymphoblastic cell lines and peripheral blood lymphocytes, respectively. In the absence of human serum, the mean IC₅₀ of lopinavir against five different HIV-1 laboratory strains was 19 nM. In the absence and presence of 50% human serum, the mean IC₅₀ of lopinavir against HIV-1_IIIB in MT4 cells was 17 nM and 102 nM, respectively. In the absence of human serum, the mean IC₅₀ of lopinavir was 6.5 nM against several HIV-1 clinical isolates.

Resistance

In vitro selection of resistanceHIV-1 isolates with reduced susceptibility to lopinavir have been selected in vitro. HIV-1 has been passaged in vitro with lopinavir alone and with lopinavir plus ritonavir at concentration ratios representing the range of plasma concentration ratios observed during Kaletra therapy. Genotypic and phenotypic analysis of viruses selected in these passages suggest that the presence of ritonavir, at these concentration ratios, does not measurably influence the selection of lopinavir-resistant viruses. Overall, the in vitro characterisation of phenotypic cross-resistance between lopinavir and other protease inhibitors suggest that decreased susceptibility to lopinavir correlated closely with decreased susceptibility to ritonavir and indinavir, but did not correlate closely with decreased susceptibility to amprenavir, saquinavir, and nelfinavir.

Analysis of resistance in ARV-naïve patients

In clinical studies with a limited number of isolates analysed, the selection of resistance to lopinavir has not been observed in naïve patients without significant protease inhibitor resistance at baseline. See further the detailed description of the clinical studies.

Analysis of resistance in PI-experienced patients

The selection of resistance to lopinavir in patients having failed prior protease inhibitor therapy was characterised by analysing the longitudinal isolates from 19 protease inhibitor-experienced subjects in 2 Phase II and one Phase III studies who either experienced incomplete virologic suppression or viral rebound subsequent to initial response to Kaletra and who demonstrated incremental in vitro resistance between baseline and rebound (defined as emergence of new mutations or 2-fold change in phenotypic susceptibility to lopinavir). Incremental resistance was most common in subjects whose baseline isolates had several protease inhibitor-associated mutations, but < 40-fold reduced susceptibility to lopinavir at baseline. Mutations V82A, I54V and M46I emerged most frequently. Mutations L33F, I50V and V32I combined with I47V/A were also observed. The 19 isolates demonstrated a 4.3-fold increase in IC₅₀ compared to baseline isolates (from 6.2- to 43-fold, compared to wild-type virus).

Genotypic correlates of reduced phenotypic susceptibility to lopinavir in viruses selected by other protease inhibitors. The in vitro antiviral activity of lopinavir against 112 clinical isolates taken from patients failing therapy with one or more protease inhibitors was assessed. Within this panel, the following mutations in HIV protease were associated with reduced in vitro susceptibility to lopinavir: L10F/I/R/V, K20M/R, L24I, M46I/L, F53L, I54L/T/V, L63P, A71I/L/T/V, V82A/F/T, I84V and L90M. The median EC₅₀ of lopinavir against isolates with 0 − 3, 4 − 5, 6 − 7 and 8 − 10 mutations at the above amino acid positions was 0.8, 2.7 13.5 and 44.0-fold higher than the EC₅₀ against wild type HIV, respectively. The 16 viruses that displayed > 20-fold change in susceptibility all contained mutations at positions 10, 54, 63 plus 82 and/or 84. In addition, they contained a median of 3 mutations at amino acid positions 20, 24, 46, 53, 71 and 90. In addition to the mutations described above, mutations V32I and I47A have been observed in rebound isolates with reduced lopinavir susceptibility from protease inhibitor experienced patients receiving Kaletra therapy, and mutations I47A and L76V have been observed in rebound isolates with reduced lopinavir susceptibility from patients receiving Kaletra therapy.

Conclusions regarding the relevance of particular mutations or mutational patterns are subject to change with additional data, and it is recommended to always consult current interpretation systems for analysing resistance test results.

Antiviral activity of Kaletra in patients failing protease inhibitor therapy

The clinical relevance of reduced in vitro susceptibility to lopinavir has been examined by assessing the virologic response to Kaletra therapy, with respect to baseline viral genotype and phenotype, in 56 patients previous failing therapy with multiple protease inhibitors. The EC₅₀ of lopinavir against the 56 baseline viral isolates ranged from 0.6 to 96-fold higher than the EC₅₀ against wild type HIV. After 48 weeks of treatment with Kaletra, efavirenz and nucleoside reverse transcriptase inhibitors, plasma HIV RNA ≤ 400 copies/ml was observed in 93% (25/27), 73% (11/15), and 25% (2/8) of patients with < 10-fold, 10 to 40-fold, and > 40-fold reduced susceptibility to lopinavir at baseline, respectively. In addition, virologic response was observed in 91% (21/23), 71% (15/21) and 33% (2/6) patients with 0 − 5, 6 − 7, and 8 − 10 mutations of the above mutations in HIV protease associated with reduced in vitro susceptibility to lopinavir. Since these patients had not previously been exposed to either Kaletra or efavirenz, part of the response may be attributed to the antiviral activity of efavirenz, particularly in patients harbouring highly lopinavir resistant virus. The study did not contain a control arm of patients not receiving Kaletra.

Cross-resistance

Activity of other protease inhibitors against isolates that developed incremental resistance to lopinavir after Kaletra therapy in protease inhibitor experienced patients: The presence of cross resistance to other protease inhibitors was analysed in 18 rebound isolates that had demonstrated evolution of resistance to lopinavir during 3 Phase II and one Phase III studies of Kaletra in protease inhibitor-experienced patients. The median fold IC₅₀ of lopinavir for these 18 isolates at baseline and rebound was 6.9- and 63-fold, respectively, compared to wild type virus. In general, rebound isolates either retained (if cross-resistant at baseline) or developed significant cross-resistance to indinavir, saquinavir and atazanavir. Modest decreases in amprenavir activity were noted with a median increase of IC₅₀ from 3.7- to 8-fold in the baseline and rebound isolates, respectively. Isolates retained susceptibility to tipranavir with a median increase of IC₅₀ in baseline and rebound isolates of 1.9- and 1.8-fold, respectively, compared to wild type virus. Please refer to the Aptivus Summary of Product Characteristics for additional information on the use of tipranavir, including genotypic predictors of response, in treatment of lopinavir-resistant HIV-1 infection.

Clinical results

The effects of Kaletra (in combination with other antiretroviral agents) on biological markers (plasma HIV RNA levels and CD4+ T-cell counts) have been investigated in controlled studies of Kaletra of 48 to 360 weeks duration.

Adult Use

Patients without prior antiretroviral therapy

Study M98-863 was a randomised, double-blind trial of 653 antiretroviral treatment naïve patients investigating Kaletra (400/100 mg twice daily) compared to nelfinavir (750 mg three times daily) plus stavudine and lamivudine. Mean baseline CD4+ T-cell count was 259 cells/mm³ (range: 2 to 949 cells/ mm³) and mean baseline plasma HIV-1 RNA was 4.9 log₁₀ copies/ml (range: 2.6 to 6.8 log₁₀ copies/ml).

Table 1

* intent to treat analysis where patients with missing values are considered virologic failures

†p < 0.001

One-hundred thirteen nelfinavir-treated patients and 74 lopinavir/ritonavir-treated patients had an HIV RNA above 400 copies/ml while on treatment from Week 24 through Week 96. Of these, isolates from 96 nelfinavir-treated patients and 51 lopinavir/ritonavir-treated patients could be amplified for resistance testing. Resistance to nelfinavir, defined as the presence of the D30N or L90M mutation in protease, was observed in 41/96 (43%) patients. Resistance to lopinavir, defined as the presence of any primary or active site mutations in protease (see above), was observed in 0/51 (0%) patients. Lack of resistance to lopinavir was confirmed by phenotypic analysis.

Sustained virological response to Kaletra (in combination with nucleoside/nucleotide reverse transcriptase inhibitors) has been also observed in a small Phase II study (M97-720) through 360 weeks of treatment. One hundred patients were originally treated with Kaletra in the study (including 51 patients receiving 400/100 mg twice daily and 49 patients at either 200/100 mg twice daily or 400/200 mg twice daily). All patients converted to open-label Kaletra at the 400/100 mg twice daily dose between week 48 and week 72. Thirty-nine patients (39%) discontinued the study, including 16 (16%) discontinuations due to adverse events, one of which was associated with a death. Sixty-one patients completed the study (35 patients received the recommended 400/100 mg twice daily dose throughout the study).

Table 2

Through 360 weeks of treatment, genotypic analysis of viral isolates was successfully conducted in 19 of 28 patients with confirmed HIV RNA above 400 copies/ml revealed no primary or active site mutations in protease (amino acids at positions 8, 30, 32, 46, 47, 48, 50, 82, 84 and 90) or protease inhibitor phenotypic resistance.

Patients with prior antiretroviral therapy

M97-765 is a randomised, double-blind trial evaluating Kaletra at two dose levels (400/100 mg and 400/200 mg, both twice daily) plus nevirapine (200 mg twice daily) and two nucleoside reverse transcriptase inhibitors in 70 single protease inhibitor experienced, non-nucleoside reverse transcriptase inhibitor naïve patients. Median baseline CD₄ cell count was 349 cells/mm³ (range 72 to 807 cells/mm³) and median baseline plasma HIV-1 RNA was 4.0 log₁₀ copies/ml (range 2.9 to 5.8 log₁₀ copies/ml).

Table 3

* intent to treat analysis where patients with missing values are considered virologic failures

M98-957 is a randomised, open-label study evaluating Kaletra treatment at two dose levels (400/100 mg and 533/133 mg, both twice daily) plus efavirenz (600 mg once daily) and nucleoside reverse transcriptase inhibitors in 57 multiple protease inhibitor experienced, non-nucleoside reverse transcriptase inhibitor naïve patients. Between week 24 and 48, patients randomised to a dose of 400/100 mg were converted to a dose of 533/133 mg. Median baseline CD₄ cell count was 220 cells/mm³ (range13 to 1030 cells/mm³).

Table 4

* intent to treat analysis where patients with missing values are considered virologic failures

Paediatric Use

M98-940 was an open-label study of a liquid formulation of Kaletra in 100 antiretroviral naïve (44%) and experienced (56%) paediatric patients. All patients were non-nucleoside reverse transcriptase inhibitor naïve. Patients were randomised to either 230 mg lopinavir/57.5 mg ritonavir per m² or 300 mg lopinavir/75 mg ritonavir per m². Naïve patients also received nucleoside reverse transcriptase inhibitors. Experienced patients received nevirapine plus up to two nucleoside reverse transcriptase inhibitors. Safety, efficacy and pharmacokinetic profiles of the two dose regimens were assessed after 3 weeks of therapy in each patient. Subsequently, all patients were continued on the 300/75 mg per m² dose. Patients had a mean age of 5 years (range 6 months to 12 years) with 14 patients less than 2 years old and 6 patients one year or less. Mean baseline CD4+ T-cell count was 838 cells/mm³ and mean baseline plasma HIV-1 RNA was 4.7 log₁₀ copies/ml.

Table 5

* intent to treat analysis where patients with missing values are considered virologic failures

Study P1030 was an open-label, dose-finding trial evaluating the pharmacokinetic profile, tolerability, safety and efficacy of Kaletra oral solution at a dose of 300 mg lopinavir/75 mg ritonavir per m² twice daily plus 2 NRTIs in HIV-1 infected infants > 14 days and < 6 months of age. At entry, median (range) HIV-1 RNA was 6.0 (4.7-7.2) log₁₀ copies/ml and median (range) CD4+T-cell percentage was 41 (16-59).

Table 6

*Proportion of subjects who had HIV-1 < 400 copies/ml and had remained on study treatment

Study P1060 was a randomised controlled trial of nevirapine versus lopinavir/ritonavir-based therapy in subjects 2 to 36 months of age infected with HIV-1 who had (Cohort I) and had not (Cohort II) been exposed to nevirapine during pregnancy for prevention of mother-to-child transmission. Lopinavir/ritonavir was administered twice daily at 16/4 mg/kg for subjects 2 months to < 6 months, 12/3 mg/kg for subjects > 6 months and < 15 kg, 10/2.5 mg/kg for subjects > 6 months and > 15 kg to < 40 kg, or 400/100 mg for subjects > 40 kg. The nevirapine-based regimen was 160-200 mg/m² once daily for 14 days, then 160-200 mg/m² every 12 hours. Both treatment arms included zidovudine 180 mg/m² every 12 hours and lamivudine 4 mg/kg every 12 hours. The median follow-up was 48 weeks in Cohort I and 72 weeks in Cohort II. At entry, median age was 0.7 years, median CD4 T-cell count was 1147 cells/mm³, median CD4 T-cell was 19%, and median HIV-1 RNA was > 750,000 copies/ml. Among 13 subjects with viral failure in the lopinavir/ritonavir group with resistance data available no resistance to lopinavir/ritonavir was found.

Table 7

*Defined as confirmed plasma HIV-1 RNA level > 400 copies/ml at 24 weeks or viral rebound > 4000 copies/ml after Week 24. Overall failure rate combining the treatment differences across age strata, weighted by the precision of the estimate within each age stratum

p=0.015 (Cohort I); p< 0.001 (Cohort II)

The CHER study was a randomized, open-label study comparing 3 treatment strategies (deferred treatment, early treatment for 40 weeks, or early treatment for 96 weeks) in children with perinatally acquired HIV-1 infection. The treatment regimen was zidovudine plus lamivudine plus 300 mg lopinavir/75 mg ritonavir per m² twice daily until 6 months of age, then 230 mg lopinavir/57.5 mg ritonavir per m² twice daily. There were no reported events of failure attributed to therapy limiting toxicity.

Table 8

* Failure defined as clinical, immunological disease progression, virological failure or regimen limiting ART toxicity

p=0.0005 (40 week arm); p< 0.0008 (96 week arm)

The pharmacokinetic properties of lopinavir co-administered with ritonavir have been evaluated in healthy adult volunteers and in HIV-infected patients; no substantial differences were observed between the two groups. Lopinavir is essentially completely metabolised by CYP3A. Ritonavir inhibits the metabolism of lopinavir, thereby increasing the plasma levels of lopinavir. Across studies, administration of Ritomax-L 400/100 mg twice daily yields mean steady-state lopinavir plasma concentrations 15 to 20-fold higher than those of ritonavir in HIV-infected patients. The plasma levels of ritonavir are less than 7% of those obtained after the ritonavir dose of 600 mg twice daily. The in vitro antiviral EC₅₀ of lopinavir is approximately 10-fold lower than that of ritonavir. Therefore, the antiviral activity of Ritomax-L is due to lopinavir.

Absorption

Multiple dosing with 400/100 mg Ritomax-L twice daily for 2 weeks and without meal restriction produced a mean ± SD lopinavir peak plasma concentration (C_max) of 12.3 ± 5.4 μg/ml, occurring approximately 4 hours after administration. The mean steady-state trough concentration prior to the morning dose was 8.1 ± 5.7 μg/ml. Lopinavir AUC over a 12 hour dosing interval averaged 113.2 ± 60.5 μg-h/ml. The absolute bioavailability of lopinavir co-formulated with ritonavir in humans has not been established.

Effects of food on oral absorption

Administration of a single 400/100 mg dose of Ritomax-L tablets under fed conditions (high fat, 872 kcal, 56% from fat) compared to fasted state was associated with no significant changes in C_max and AUC_inf. Therefore, Ritomax-L tablets may be taken with or without food. Ritomax-L tablets have also shown less pharmacokinetic variability under all meal conditions compared to Ritomax-L soft capsules.

Distribution

At steady state, lopinavir is approximately 98 − 99% bound to serum proteins. Lopinavir binds to both alpha-1-acid glycoprotein (AAG) and albumin however, it has a higher affinity for AAG. At steady state, lopinavir protein binding remains constant over the range of observed concentrations after 400/100 mg Ritomax-L twice daily, and is similar between healthy volunteers and HIV-positive patients.

Biotransformation

In vitro experiments with human hepatic microsomes indicate that lopinavir primarily undergoes oxidative metabolism. Lopinavir is extensively metabolised by the hepatic cytochrome P450 system, almost exclusively by isozyme CYP3A. Ritonavir is a potent CYP3A inhibitor which inhibits the metabolism of lopinavir and therefore, increases plasma levels of lopinavir. A ¹⁴C-lopinavir study in humans showed that 89% of the plasma radioactivity after a single 400/100 mg Ritomax-L dose was due to parent active substance. At least 13 lopinavir oxidative metabolites have been identified in man. The 4-oxo and 4-hydroxymetabolite epimeric pair are the major metabolites with antiviral activity, but comprise only minute amounts of total plasma radioactivity. Ritonavir has been shown to induce metabolic enzymes, resulting in the induction of its own metabolism, and likely the induction of lopinavir metabolism. Pre-dose lopinavir concentrations decline with time during multiple dosing, stabilising after approximately 10 days to 2 weeks.

Elimination

After a 400/100 mg ¹⁴C-lopinavir/ritonavir dose, approximately 10.4 ± 2.3% and 82.6 ± 2.5% of an administered dose of ¹⁴C-lopinavir can be accounted for in urine and faeces, respectively. Unchanged lopinavir accounted for approximately 2.2% and 19.8% of the administered dose in urine and faeces, respectively. After multiple dosing, less than 3% of the lopinavir dose is excreted unchanged in the urine. The effective (peak to trough) half-life of lopinavir over a 12 hour dosing interval averaged 5 − 6 hours, and the apparent oral clearance (CL/F) of lopinavir is 6 to 7 l/h.

Once-daily dosing: the pharmacokinetics of once daily Ritomax-L have been evaluated in HIV-infected subjects naïve to antiretroviral treatment. Ritomax-L 800/200 mg was administered in combination with emtricitabine 200 mg and tenofovir DF 300 mg as part of a once-daily regimen. Multiple dosing of 800/200 mg Ritomax-L once daily for 2 weeks without meal restriction (n=16) produced a mean ± SD lopinavir peak plasma concentration (C_max) of 14.8 ± 3.5 μg/ml, occurring approximately 6 hours after administration. The mean steady-state trough concentration prior to the morning dose was 5.5 ± 5.4 μg/ml. Lopinavir AUC over a 24 hour dosing interval averaged 206.5 ± 89.7 μg-h/ml.

As compared to the BID regimen, the once-daily dosing is associated with a reduction in the C_min/C_trough values of approximately 50%.

Special Populations

Paediatrics

There are limited pharmacokinetic data in children below 2 years of age. The pharmacokinetics of Ritomax-L oral solution 300/75 mg/m² twice daily and 230/57.5 mg/m² twice daily have been studied in a total of 53 paediatric patients, ranging in age from 6 months to 12 years. The lopinavir mean steady-state AUC, C_max, and C_min were 72.6 ± 31.1 μg-h/ml, 8.2 ± 2.9 μg/ml and 3.4 ± 2.1 μg/ml, respectively after Ritomax-L oral solution 230/57.5 mg/m² twice daily without nevirapine (n=12), and were 85.8 ± 36.9 μg-h/ml, 10.0 ± 3.3 μg/ml and 3.6 ± 3.5 μg/ml, respectively after 300/75 mg/m² twice daily with nevirapine (n=12). The 230/57.5 mg/m² twice-daily regimen without nevirapine and the 300/75 mg/m² twice-daily regimen with nevirapine provided lopinavir plasma concentrations similar to those obtained in adult patients receiving the 400/100 mg twice-daily regimen without nevirapine.

Gender, Race and Age

Ritomax-L pharmacokinetics have not been studied in older people. No age or gender related pharmacokinetic differences have been observed in adult patients. Pharmacokinetic differences due to race have not been identified.

Pregnancy and postpartum

In an open-label pharmacokinetic study, 12 HIV-infected pregnant women who were less than 20 weeks of gestation and on combination antiretroviral therapy initially received lopinavir/ritonavir 400 mg/100 mg (two 200/50 mg tablets) twice daily up to a gestational age of 30 weeks. At 30 weeks age of gestation, the dose was increased to 500/125 mg (two 200/50 mg tablets plus one 100/25 mg tablet) twice daily until subjects were 2 weeks postpartum. Plasma concentrations of lopinavir were measured over four 12-hour periods during second trimester (20-24 weeks gestation), third trimester before dose increase (30 weeks gestation), third trimester after dose increase (32 weeks gestation), and at 8 weeks post-partum. The dose increase did not result in a significant increase in the plasma lopinavir concentration.

In another open-label pharmacokinetic study, 19 HIV-infected pregnant women received lopinavir/ritonavir 400/100 mg twice daily as part of combination antiretroviral therapy during pregnancy from before conception. A series of blood samples were collected pre-dose and at intervals over the course of 12 hours in trimester 2 and trimester 3, at birth, and 4-6 weeks postpartum (in women who continued treatment post-delivery) for pharmacokinetic analysis of total and unbound levels of plasma lopinavir concentrations.

The pharmacokinetic data from HIV-1 infected pregnant women receiving lopinavir/ritonavir tablets 400/100 mg twice daily are presented in Table 6.

Table 6

Renal Insufficiency

Ritomax-L pharmacokinetics have not been studied in patients with renal insufficiency; however, since the renal clearance of lopinavir is negligible, a decrease in total body clearance is not expected in patients with renal insufficiency.

Hepatic Insufficiency

The steady state pharmacokinetic parameters of lopinavir in HIV-infected patients with mild to moderate hepatic impairment were compared with those of HIV-infected patients with normal hepatic function in a multiple dose study with lopinavir/ritonavir 400/100 mg twice daily. A limited increase in total lopinavir concentrations of approximately 30% has been observed which is not expected to be of clinical relevance.

The pharmacokinetic properties of lopinavir co-administered with ritonavir have been evaluated in healthy adult volunteers and in HIV-infected patients; no substantial differences were observed between the two groups. Lopinavir is essentially completely metabolised by CYP3A. Ritonavir inhibits the metabolism of lopinavir, thereby increasing the plasma levels of lopinavir. Across studies, administration of Kaletra 400/100 mg twice daily yields mean steady-state lopinavir plasma concentrations 15 to 20-fold higher than those of ritonavir in HIV-infected patients. The plasma levels of ritonavir are less than 7% of those obtained after the ritonavir dose of 600 mg twice daily. The in vitro antiviral EC₅₀ of lopinavir is approximately 10-fold lower than that of ritonavir. Therefore, the antiviral activity of Kaletra is due to lopinavir.

Absorption

Multiple dosing with 400/100 mg Kaletra twice daily for 2 weeks and without meal restriction produced a mean ± SD lopinavir peak plasma concentration (C_max) of 12.3 ± 5.4 μg/ml, occurring approximately 4 hours after administration. The mean steady-state trough concentration prior to the morning dose was 8.1 ± 5.7 μg/ml. Lopinavir AUC over a 12 hour dosing interval averaged 113.2 ± 60.5 μg-h/ml. The absolute bioavailability of lopinavir co-formulated with ritonavir in humans has not been established.

Effects of food on oral absorption

Kaletra soft capsules and liquid have been shown to be bioequivalent under nonfasting conditions (moderate fat meal). Administration of a single 400/100 mg dose of Kaletra soft capsules with a moderate fat meal (500 - 682 kcal, 22.7 -25.1% from fat) was associated with a mean increase of 48% and 23% in lopinavir AUC and C_max, respectively, relative to fasting. For Kaletra oral solution, the corresponding increases in lopinavir AUC and C_max were 80% and 54%, respectively. Administration of Kaletra with a high fat meal (872 kcal, 55.8% from fat) increased lopinavir AUC and C_max by 96% and 43%, respectively, for soft capsules, and 130% and 56%, respectively, for oral solution. To enhance bioavailability and minimise variability Kaletra is to be taken with food.

Distribution

At steady state, lopinavir is approximately 98 − 99% bound to serum proteins. Lopinavir binds to both alpha-1-acid glycoprotein (AAG) and albumin however, it has a higher affinity for AAG. At steady state, lopinavir protein binding remains constant over the range of observed concentrations after 400/100 mg Kaletra twice daily, and is similar between healthy volunteers and HIV-positive patients.

Biotransformation

In vitro experiments with human hepatic microsomes indicate that lopinavir primarily undergoes oxidative metabolism. Lopinavir is extensively metabolised by the hepatic cytochrome P450 system, almost exclusively by isozyme CYP3A. Ritonavir is a potent CYP3A inhibitor which inhibits the metabolism of lopinavir and therefore, increases plasma levels of lopinavir. A ¹⁴C-lopinavir study in humans showed that 89% of the plasma radioactivity after a single 400/100 mg Kaletra dose was due to parent active substance. At least 13 lopinavir oxidative metabolites have been identified in man. The 4-oxo and 4-hydroxymetabolite epimeric pair are the major metabolites with antiviral activity, but comprise only minute amounts of total plasma radioactivity. Ritonavir has been shown to induce metabolic enzymes, resulting in the induction of its own metabolism, and likely the induction of lopinavir metabolism. Pre-dose lopinavir concentrations decline with time during multiple dosing, stabilising after approximately 10 days to 2 weeks.

Elimination

After a 400/100 mg ¹⁴C-lopinavir/ritonavir dose, approximately 10.4 ± 2.3% and 82.6 ± 2.5% of an administered dose of ¹⁴C-lopinavir can be accounted for in urine and faeces, respectively. Unchanged lopinavir accounted for approximately 2.2% and 19.8% of the administered dose in urine and faeces, respectively. After multiple dosing, less than 3% of the lopinavir dose is excreted unchanged in the urine. The effective (peak to trough) half-life of lopinavir over a 12 hour dosing interval averaged 5 − 6 hours, and the apparent oral clearance (CL/F) of lopinavir is 6 to 7 l/h.

Special Populations

Paediatrics

Data from clinical trials in children below 2 years of age include the pharmacokinetics of Kaletra 300/75 mg/m² twice daily studied in a total of 31 paediatric patients, ranging in age from 14 days to 6 months. The pharmacokinetics of Kaletra 300/75 mg/m² twice daily with nevirapine and 230/57.5 mg/ m² twice daily alone have been studied in 53 paediatric patients ranging in age from 6 months to 12 years. The mean (SD) for the studies are reported in the table below. The 230/57.5 mg/m² twice daily regimen without nevirapine and the 300/75 mg/m² twice daily regimen with nevirapine provided lopinavir plasma concentrations similar to those obtained in adult patients receiving the 400/100 mg twice daily regimen without nevirapine.

a. Kaletra oral solution 230/57.5 mg/m² twice daily regimen without nevirapine

b. Kaletra oral solution 300/75 mg/m² twice daily regimen with nevirapine

c. Kaletra film-coated tablets 400/100 mg twice daily at steady state

Gender, Race and Age

Kaletra pharmacokinetics have not been studied in older people. No age or gender related pharmacokinetic differences have been observed in adult patients. Pharmacokinetic differences due to race have not been identified.

Renal Insufficiency

Kaletra pharmacokinetics have not been studied in patients with renal insufficiency; however, since the renal clearance of lopinavir is negligible, a decrease in total body clearance is not expected in patients with renal insufficiency.

Hepatic Insufficiency

The steady state pharmacokinetic parameters of lopinavir in HIV-infected patients with mild to moderate hepatic impairment were compared with those of HIV-infected patients with normal hepatic function in a multiple dose study with lopinavir/ritonavir 400/100 mg twice daily. A limited increase in total lopinavir concentrations of approximately 30% has been observed which is not expected to be of clinical relevance.

Repeat-dose toxicity studies in rodents and dogs identified major target organs as the liver, kidney, thyroid, spleen and circulating red blood cells. Hepatic changes indicated cellular swelling with focal degeneration. While exposure eliciting these changes were comparable to or below human clinical exposure, dosages in animals were over 6-fold the recommended clinical dose. Mild renal tubular degeneration was confined to mice exposed with at least twice the recommended human exposure; the kidney was unaffected in rats and dogs. Reduced serum thyroxin led to an increased release of TSH with resultant follicular cell hypertrophy in the thyroid glands of rats. These changes were reversible with withdrawal of the active substance and were absent in mice and dogs. Coombs-negative anisocytosis and poikilocytosis were observed in rats, but not in mice or dogs. Enlarged spleens with histiocytosis were seen in rats but not other species. Serum cholesterol was elevated in rodents but not dogs, while triglycerides were elevated only in mice.

During in vitro studies, cloned human cardiac potassium channels (HERG) were inhibited by 30% at the highest concentrations of lopinavir/ritonavir tested, corresponding to a lopinavir exposure 7-fold total and 15-fold free peak plasma levels achieved in humans at the maximum recommended therapeutic dose. In contrast, similar concentrations of lopinavir/ritonavir demonstrated no repolarisation delay in the canine cardiac Purkinje fibres. Lower concentrations of lopinavir/ritonavir did not produce significant potassium (HERG) current blockade. Tissue distribution studies conducted in the rat did not suggest significant cardiac retention of the active substance; 72-hour AUC in heart was approximately 50% of measured plasma AUC. Therefore, it is reasonable to expect that cardiac lopinavir levels would not be significantly higher than plasma levels.

In dogs, prominent U waves on the electrocardiogram have been observed associated with prolonged PR interval and bradycardia. These effects have been assumed to be caused by electrolyte disturbance.

In rats, embryofoetotoxicity (pregnancy loss, decreased foetal viability, decreased foetal body weights, increased frequency of skeletal variations) and postnatal developmental toxicity (decreased survival of pups) was observed at maternally toxic dosages. The systemic exposure to lopinavir/ritonavir at the maternal and developmental toxic dosages was lower than the intended therapeutic exposure in humans.

Long-term carcinogenicity studies of lopinavir/ritonavir in mice revealed a nongenotoxic, mitogenic induction of liver tumours, generally considered to have little relevance to human risk.

Carcinogenicity studies in rats revealed no tumourigenic findings. Lopinavir/ritonavir was not found to be mutagenic or clastogenic in a battery of in vitro and in vivo assays including the Ames bacterial reverse mutation assay, the mouse lymphoma assay, the mouse micronucleus test and chromosomal aberration assays in human lymphocytes.

Repeat-dose toxicity studies in rodents and dogs identified major target organs as the liver, kidney, thyroid, spleen and circulating red blood cells. Hepatic changes indicated cellular swelling with focal degeneration. While exposure eliciting these changes were comparable to or below human clinical exposure, dosages in animals were over 6-fold the recommended clinical dose. Mild renal tubular degeneration was confined to mice exposed with at least twice the recommended human exposure; the kidney was unaffected in rats and dogs. Reduced serum thyroxin led to an increased release of TSH with resultant follicular cell hypertrophy in the thyroid glands of rats. These changes were reversible with withdrawal of the active substance and were absent in mice and dogs. Coombs-negative anisocytosis and poikilocytosis were observed in rats, but not in mice or dogs. Enlarged spleens with histiocytosis were seen in rats but not other species. Serum cholesterol was elevated in rodents but not dogs, while triglycerides were elevated only in mice.

During in vitro studies, cloned human cardiac potassium channels (HERG) were inhibited by 30% at the highest concentrations of lopinavir/ritonavir tested, corresponding to a lopinavir exposure 7-fold total and 15-fold free peak plasma levels achieved in humans at the maximum recommended therapeutic dose. In contrast, similar concentrations of lopinavir/ritonavir demonstrated no repolarisation delay in the canine cardiac Purkinje fibres. Lower concentrations of lopinavir/ritonavir did not produce significant potassium (HERG) current blockade. Tissue distribution studies conducted in the rat did not suggest significant cardiac retention of the active substance; 72-hour AUC in heart was approximately 50% of measured plasma AUC. Therefore, it is reasonable to expect that cardiac lopinavir levels would not be significantly higher than plasma levels.

In dogs, prominent U waves on the electrocardiogram have been observed associated with prolonged PR interval and bradycardia. These effects have been assumed to be caused by electrolyte disturbance.

In rats, embryofoetotoxicity (pregnancy loss, decreased foetal viability, decreased foetal body weights, increased frequency of skeletal variations) and postnatal developmental toxicity (decreased survival of pups) was observed at maternally toxic dosages. The systemic exposure to lopinavir/ritonavir at the maternal and developmental toxic dosages was lower than the intended therapeutic exposure in humans.

Long-term carcinogenicity studies of lopinavir/ritonavir in mice revealed a nongenotoxic, mitogenic induction of liver tumours, generally considered to have little relevance to human risk. Carcinogenicity studies in rats revealed no tumourigenic findings. Lopinavir/ritonavir was not found to be mutagenic or clastogenic in a battery of in vitro and in vivo assays including the Ames bacterial reverse mutation assay, the mouse lymphoma assay, the mouse micronucleus test and chromosomal aberration assays in human lymphocytes.