Moxamar

Moxamar is indicated in adults for treatment of mild to moderate essential hypertension.

Moxamaridine is indicated in adults for treatment of mild to moderate essential hypertension.

Posology

Adults

Treatment must be instituted with the lowest dosage of Moxamar. This means a daily dose of 0.2 mg Moxamar in the morning. If the therapeutic effect is insufficient, the dose can be increased after three weeks to 0.4 mg. This dose can be given as a single dose (to be taken in the morning) or as a divided daily dose (morning and evening). If the results are still insufficient after a further three weeks, the dosage can be increased further to a maximum of 0.6 mg given divided in the morning and evening. A single dose of 0.4 mg Moxamar and a daily dose of 0.6 mg Moxamar should not be exceeded.

Special populations

Elderly

Provided that renal function is not impaired, dosage recommendation is the same as for adults.

Paediatric population

Moxamar should not be given to children and adolescents under 18 years of age as insufficient safety and therapeutic data are available for this.

Method of administration

As concomitant ingestion of food does not affect the pharmacokinetics of Moxamar, Moxamar can be taken before, during or after meals. The tablets should be taken with sufficient fluid.

Posology

Adults

Treatment must be instituted with the lowest dosage of Moxamaridine. This means a daily dose of 0.2 mg Moxamaridine in the morning. If the therapeutic effect is insufficient, the dose can be increased after three weeks to 0.4 mg. This dose can be given as a single dose (to be taken in the morning) or as a divided daily dose (morning and evening). If the results are still insufficient after a further three weeks, the dosage can be increased further to a maximum of 0.6 mg given divided in the morning and evening. A single dose of 0.4 mg Moxamaridine and a daily dose of 0.6 mg Moxamaridine should not be exceeded.

Special populations

Elderly

Provided that renal function is not impaired, dosage recommendation is the same as for adults.

Paediatric population

Moxamaridine should not be given to children and adolescents under 18 years of age as insufficient safety and therapeutic data are available for this.

Method of administration

As concomitant ingestion of food does not affect the pharmacokinetics of Moxamaridine, Moxamaridine can be taken before, during or after meals. The tablets should be taken with sufficient fluid.

Moxamar is contraindicated in patients with:

- sick sinus syndrome

- bradycardia (resting HR <50 beats/minute)

- 2nd or 3rd degree atrioventricular block

- cardiac insufficiency

Moxamaridine is contraindicated in patients with:

- sick sinus syndrome

- bradycardia (resting HR <50 beats/minute)

- 2nd or 3rd degree atrioventricular block

- cardiac insufficiency

Cases of varying degrees of AV block have been reported in the post-marketing setting in patients undergoing Moxamar treatment. Based on these case reports, the causative role of Moxamar in delaying atrioventricular conduction cannot be completely ruled out. Therefore, caution is recommended when treating patients with a possible predisposition to developing an AV block.

When Moxamar is used in patients with 1^st degree AV block special care should be exercised to avoid bradycardia. Moxamar must not be used in higher degree AV blocks.

When Moxamar is used in patients with severe coronary artery disease or unstable angina pectoris special care should be exercised due to the fact that there is limited experience in this patient population.

Due to lack of clinical evidence supporting safe use in patients with co-existing moderate cardiac insufficiency, Moxamar should be administered with caution in these patients.

Caution is advised in the administration of Moxamar to patients with renal impairment as Moxamar is excreted primarily via the kidneys. In these patients careful titration of the dose is recommended, especially at the start of therapy. Dosing should be initiated with 0.2 mg daily and can be increased to a maximum of 0.4 mg daily for patients with moderate renal impairment (GFR>30 ml/min but < 60 ml/min) and to a maximum of 0.3 mg daily for patients with severe renal impairment (GFR<30 ml/min) if clinically indicated and well tolerated.

If Moxamar is used in combination with a β-blocker, and both treatments have to be discontinued the β-blocker should be discontinued first, and, then Moxamar after a few days.

So far, no rebound effect on blood pressure has been observed after the discontinuation of treatment with Moxamar. However, it is advisable not to stop taking Moxamar abruptly, but to reduce it gradually over a period of two weeks.

The elderly population may be more susceptible to the CV effects of blood pressure lowering drugs. Therefore therapy should be started with the lowest dose and dose increments should be introduced with caution to prevent the serious consequences these reactions may lead to.

Moxamar contains lactose. Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption should not take this medicine.

Cases of varying degrees of AV block have been reported in the post-marketing setting in patients undergoing Moxamaridine treatment. Based on these case reports, the causative role of Moxamaridine in delaying atrioventricular conduction cannot be completely ruled out. Therefore, caution is recommended when treating patients with a possible predisposition to developing an AV block.

When Moxamaridine is used in patients with 1^st degree AV block special care should be exercised to avoid bradycardia. Moxamaridine must not be used in higher degree AV blocks.

When Moxamaridine is used in patients with severe coronary artery disease or unstable angina pectoris special care should be exercised due to the fact that there is limited experience in this patient population.

Due to lack of clinical evidence supporting safe use in patients with co-existing moderate cardiac insufficiency, Moxamaridine should be administered with caution in these patients.

Caution is advised in the administration of Moxamaridine to patients with renal impairment as Moxamaridine is excreted primarily via the kidneys. In these patients careful titration of the dose is recommended, especially at the start of therapy. Dosing should be initiated with 0.2 mg daily and can be increased to a maximum of 0.4 mg daily for patients with moderate renal impairment (GFR>30 ml/min but < 60 ml/min) and to a maximum of 0.3 mg daily for patients with severe renal impairment (GFR<30 ml/min) if clinically indicated and well tolerated.

If Moxamaridine is used in combination with a β-blocker, and both treatments have to be discontinued the β-blocker should be discontinued first, and, then Moxamaridine after a few days.

So far, no rebound effect on blood pressure has been observed after the discontinuation of treatment with Moxamaridine. However, it is advisable not to stop taking Moxamaridine abruptly, but to reduce it gradually over a period of two weeks.

The elderly population may be more susceptible to the CV effects of blood pressure lowering drugs. Therefore therapy should be started with the lowest dose and dose increments should be introduced with caution to prevent the serious consequences these reactions may lead to.

Moxamaridine contains lactose. Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption should not take this medicine.

Most frequent side effects reported by those taking Moxamar include dry mouth, dizziness, asthenia and somnolence. These symptoms often decrease after the first few weeks of treatment. Undesirable Effects by System Organ Class (observed during placebo-controlled clinical trials with n=886 patients exposed to Moxamar resulted in frequencies below):

*there was no increase in frequency compared to placebo

*there was no increase in frequency compared to placebo

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 at: www.mhra.gov.uk/yellowcard.

Most frequent side effects reported by those taking Moxamaridine include dry mouth, dizziness, asthenia and somnolence. These symptoms often decrease after the first few weeks of treatment. Undesirable Effects by System Organ Class (observed during placebo-controlled clinical trials with n=886 patients exposed to Moxamaridine resulted in frequencies below):

*there was no increase in frequency compared to placebo

*there was no increase in frequency compared to placebo

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 at: www.mhra.gov.uk/yellowcard.

Symptoms of overdose

In the few cases of overdose that have been reported, a dose of 19.6 mg was ingested acutely without fatality. Signs and symptoms reported included: headache, sedation, somnolence, hypotension, dizziness, asthenia, bradycardia, dry mouth, vomiting, fatigue and upper abdominal pain. Based on the pharmacodynamic properties of Moxamar, the following reactions may be expected in adults: headache, sedation, somnolence, hypotension, orthostatic dysregulation, dizziness, asthenia, bradycardia, dry mouth, fatigue and upper abdominal pain. In rare cases, emesis and a transient paradoxical increase in blood pressure can occur. In case of a severe overdose close monitoring of especially consciousness disturbances and respiratory depression is recommended.

In addition, based on a few high dose studies in animals, transient hypertension, tachycardia and hyperglycaemia may also occur.

Treatment of overdose

In the case of a severe overdose, in particular the observation of disorders of consciousness and respiratory depression is advisable. Treatment consists of absorption-reducing measures such as gastric lavage (if shortly after ingestion), administration of activated charcoal and laxatives, and otherwise is symptomatic.

No specific antidote is known.

In case of hypotension, circulatory support such as fluids and dopamine administration may be considered. Bradycardia may be treated with atropine. Alpha-receptor antagonists may diminish or abolish the paradoxical hypertensive effects of a Moxamar overdose.

Paediatric population

The following case of inadvertent overdose in a 2-year old child has been described:

The child ingested an unknown quantity of Moxamar. The maximum dose that could have been taken was 14 mg. The child exhibited the following symptoms: Sedation, coma hypotension, miosis and dyspnoea. Gastric lavage, glucose infusions, mechanical ventilation and rest resulted in the symptoms completely disappearing over the course of 11 hours.

Symptoms of overdose

In the few cases of overdose that have been reported, a dose of 19.6 mg was ingested acutely without fatality. Signs and symptoms reported included: headache, sedation, somnolence, hypotension, dizziness, asthenia, bradycardia, dry mouth, vomiting, fatigue and upper abdominal pain. Based on the pharmacodynamic properties of Moxamaridine, the following reactions may be expected in adults: headache, sedation, somnolence, hypotension, orthostatic dysregulation, dizziness, asthenia, bradycardia, dry mouth, fatigue and upper abdominal pain. In rare cases, emesis and a transient paradoxical increase in blood pressure can occur. In case of a severe overdose close monitoring of especially consciousness disturbances and respiratory depression is recommended.

In addition, based on a few high dose studies in animals, transient hypertension, tachycardia and hyperglycaemia may also occur.

Treatment of overdose

In the case of a severe overdose, in particular the observation of disorders of consciousness and respiratory depression is advisable. Treatment consists of absorption-reducing measures such as gastric lavage (if shortly after ingestion), administration of activated charcoal and laxatives, and otherwise is symptomatic.

No specific antidote is known.

In case of hypotension, circulatory support such as fluids and dopamine administration may be considered. Bradycardia may be treated with atropine. Alpha-receptor antagonists may diminish or abolish the paradoxical hypertensive effects of a Moxamaridine overdose.

Paediatric population

The following case of inadvertent overdose in a 2-year old child has been described:

The child ingested an unknown quantity of Moxamaridine. The maximum dose that could have been taken was 14 mg. The child exhibited the following symptoms: Sedation, coma hypotension, miosis and dyspnoea. Gastric lavage, glucose infusions, mechanical ventilation and rest resulted in the symptoms completely disappearing over the course of 11 hours.

Pharmacotherapeutic group: Antihypertensives, antiadrenergic agents, centrally acting

ATC code: C02AC05

In various animal models it has been shown that Moxamar has a strongly hypotensive effect. Available experimental data indicate that the site of action of Moxamar is located in the central nervous system (CNS).

In the brain stem, Moxamar binds selectively to I₁-imidazoline receptors. These imidazoline-sensitive receptors are predominantly found in the rostral ventrolateral medulla, an area which plays an important role in central control of the sympathetic nervous system. The effect of this interaction with these I₁-imidazoline receptors appears to be a reduction in the activity of the sympathetic nerves. This has been demonstrated for cardiac, splanchnic and renal sympathetic nerves.

Moxamar differs from other centrally acting antihypertensives in the fact that it has only a weak affinity for the central α₂-adrenergic receptors compared to the affinity for I₁-imidazoline receptors. Alpha₂-adrenergic receptors are considered to be the intermediate pathway that causes sedation and dry mouth, the most commonly observed undesirable effects of centrally acting antihypertensives.

Mean systolic and diastolic blood pressure is reduced both at rest and during exercise. The effects of Moxamar on mortality and cardiovascular morbidity are currently unknown.

In humans, Moxamar leads to a reduction of systemic vascular resistance and consequently in arterial blood pressure.

Pharmacotherapeutic group: Antihypertensives, antiadrenergic agents, centrally acting

ATC code: C02AC05

In various animal models it has been shown that Moxamaridine has a strongly hypotensive effect. Available experimental data indicate that the site of action of Moxamaridine is located in the central nervous system (CNS).

In the brain stem, Moxamaridine binds selectively to I₁-imidazoline receptors. These imidazoline-sensitive receptors are predominantly found in the rostral ventrolateral medulla, an area which plays an important role in central control of the sympathetic nervous system. The effect of this interaction with these I₁-imidazoline receptors appears to be a reduction in the activity of the sympathetic nerves. This has been demonstrated for cardiac, splanchnic and renal sympathetic nerves.

Moxamaridine differs from other centrally acting antihypertensives in the fact that it has only a weak affinity for the central α₂-adrenergic receptors compared to the affinity for I₁-imidazoline receptors. Alpha₂-adrenergic receptors are considered to be the intermediate pathway that causes sedation and dry mouth, the most commonly observed undesirable effects of centrally acting antihypertensives.

Mean systolic and diastolic blood pressure is reduced both at rest and during exercise. The effects of Moxamaridine on mortality and cardiovascular morbidity are currently unknown.

In humans, Moxamaridine leads to a reduction of systemic vascular resistance and consequently in arterial blood pressure.

Absorption

Moxamar is rapidly absorbed after oral administration. In humans, approximately 90% of an oral dose is absorbed. Ingestion of food has no effect on the pharmacokinetics of Moxamar. There is no first-pass metabolism and bioavailability is 88 %.

Distribution

Only about 7% of Moxamar is bound to human plasma proteins (Vd_ss = 1.8 ± 0.4 l/kg). Peak plasma levels of Moxamar are reached 30-180 minutes after administration of a film-coated tablet.

Biotransformation

Moxamar is 10-20% metabolised, predominantly to 4,5-dehydroMoxamar and to an aminomethanamidine derivative by opening of the imidazoline ring. The hypotensive effect of 4,5-dehydroMoxamar is only 1/10, and that of the aminomethanamidine derivative less than 1/100, of that of Moxamar.

Elimination

Moxamar and its metabolites are almost entirely eliminated via the kidney. More than 90% of the dose is eliminated in the first 24 hours via the kidney, while approximately 1% is eliminated in the faeces. The cumulative excretion of unchanged Moxamar is approximately 50-75%. The mean plasma elimination half-life is 2.2-2.3 hours and the renal half-life 2.6-2.8 hours.

Characteristics in patients with renal impairment

In patients with moderately impaired renal function (GFR 30 - 60 ml/min), the AUC increased by 85% and the clearance decreased by 52%. In such patients the hypotensive effect of Moxamar should be closely monitored, especially at the start of treatment. The dose must be adapted in these patients so that the maximum daily dose is not more than 0.4 mg and the maximum single dose is 0.2 mg.

In patients with severely impaired renal function (GFR < 30 ml/min) the clearance is reduced by 68 % and the elimination half live is prolonged up to 7 hours. In these patients Moxamar dosing should be initiated with 0.2 mg daily and can be increased to a maximum of 0.3 mg daily, if clinically indicated and well tolerated. In such patients the hypotensive effect of Moxamar should be closely monitored, especially at the start of treatment.

Paediatric population

No pharmacokinetic studies in children have been performed.

Absorption

Moxamaridine is rapidly absorbed after oral administration. In humans, approximately 90% of an oral dose is absorbed. Ingestion of food has no effect on the pharmacokinetics of Moxamaridine. There is no first-pass metabolism and bioavailability is 88 %.

Distribution

Only about 7% of Moxamaridine is bound to human plasma proteins (Vd_ss = 1.8 ± 0.4 l/kg). Peak plasma levels of Moxamaridine are reached 30-180 minutes after administration of a film-coated tablet.

Biotransformation

Moxamaridine is 10-20% metabolised, predominantly to 4,5-dehydroMoxamaridine and to an aminomethanamidine derivative by opening of the imidazoline ring. The hypotensive effect of 4,5-dehydroMoxamaridine is only 1/10, and that of the aminomethanamidine derivative less than 1/100, of that of Moxamaridine.

Elimination

Moxamaridine and its metabolites are almost entirely eliminated via the kidney. More than 90% of the dose is eliminated in the first 24 hours via the kidney, while approximately 1% is eliminated in the faeces. The cumulative excretion of unchanged Moxamaridine is approximately 50-75%. The mean plasma elimination half-life is 2.2-2.3 hours and the renal half-life 2.6-2.8 hours.

Characteristics in patients with renal impairment

In patients with moderately impaired renal function (GFR 30 - 60 ml/min), the AUC increased by 85% and the clearance decreased by 52%. In such patients the hypotensive effect of Moxamaridine should be closely monitored, especially at the start of treatment. The dose must be adapted in these patients so that the maximum daily dose is not more than 0.4 mg and the maximum single dose is 0.2 mg.

In patients with severely impaired renal function (GFR < 30 ml/min) the clearance is reduced by 68 % and the elimination half live is prolonged up to 7 hours. In these patients Moxamaridine dosing should be initiated with 0.2 mg daily and can be increased to a maximum of 0.3 mg daily, if clinically indicated and well tolerated. In such patients the hypotensive effect of Moxamaridine should be closely monitored, especially at the start of treatment.

Paediatric population

No pharmacokinetic studies in children have been performed.