Kai Tong

Kai Tong® (alprostadil for injection) is indicated for the treatment of erectile dysfunction due to neurogenic, vasculogenic, psychogenic, or mixed etiology.

Treatment of erectile dysfunction of primarily organic etiology.

Adjunct to other tests in the diagnosis and management of erectile dysfunction.

Kai Tong is indicated for the treatment of erectile dysfunction in adult males due to neurogenic, vasculogenic, psychogenic or mixed aetiology.

Kai Tong may be a useful adjunct to other diagnostic tests in the diagnosis of erectile dysfunction.

Kai Tong is not indicated for paediatric use.

Prostin VR is indicated to temporarily maintain the patency of the ductus arteriosus until corrective or palliative surgery can be performed in infants who have congenital defects and who depend upon the patent ductus for survival. Such congenital heart defects include pulmonary atresia, pulmonary stenosis, tricuspid atresia, tetralogy of Fallot, interruption of the aortic arch, co-arctation of the aorta, aortic stenosis, aortic atresia, mitral atresia, or transposition of the great vessels with or without other defects.

Kai Tong® (alprostadil for injection) in the Treatment of Erectile Dysfunction

The dosage range of Kai Tong® (alprostadil for injection) for the treatment of erectile dysfunction is 1 to 40 mcg. The intracavernous injection should be given over a 5 to 10 second interval. In a study with a dose range of 1 to 20 mcg of Kai Tong® (alprostadil for injection) , the mean dose was 10.7 mcg at the end of the dose titration period. In two studies with a dose range of 1 to 40 mcg of Kai Tong® (alprostadil for injection) , the mean dose was 21.9 mcg at the end of the dose titration period. Doses greater than 40 mcg have not been studied. A ½ inch, 27 to 30 gauge needle is generally recommended for the intracavernous injection. The patient is advised not to exceed the optimum Kai Tong® (alprostadil for injection) dose which was determined in the doctor's office. The lowest possible effective dose should always be used.

Initial Titration in Physician's Office

Erectile Dysfunction of Vasculogenic, Psychogenic, or Mixed Etiology: Dosage titration should be initiated at 2.5 micrograms of alprostadil. If there is a partial response, the dose may be increased by 2.5 micrograms to a dose of 5 micrograms and then in increments of 5 to 10 micrograms, depending upon erectile response, until the dose that produces an erection suitable for intercourse and not exceeding a duration of 1 hour is reached. If there is no response to the initial 2.5-microgram dose, the second dose may be increased to 7.5 micrograms, followed by increments of 5 to 10 micrograms. The patient must stay in the physician's office until complete detumescence occurs. It there is no response, then the next higher dose may be given within 1 hour. If there is a response, then there should be at least a 1-day interval before the next dose is given.

Erectile Dysfunction of Pure Neurogenic Etiology (Spinal Cord Injury): Dosage titration should be initiated at 1.25 micrograms of alprostadil. The dose may be increased by 1.25 micrograms to a dose of 2.5 micrograms, followed by an increment of 2.5 micrograms to a dose of 5 micrograms, and then in 5-microgram increments until the dose that produces an erection suitable for intercourse and not exceeding a duration of 1 hour is reached. The patient must stay in the physician's office until complete detumescence occurs. If there is no response, then the next higher dose may be given within 1 hour. If there is a response, then there should be at least a 1-day interval before the next dose is given.

At-Home (Maintenance Therapy) Dosing Instructions

The first injections of Kai Tong® (alprostadil for injection) must be done at the physician's office by medically trained personnel. Self-injection therapy by the patient can be started only after the patient is properly instructed and well trained in the self-injection technique. The physician should instruct the patient to discard any needles which become bent during the self-injection procedure as these needles may break. The physician should make a careful assessment of the patient's skills and competence with the self-injection procedure. The intracavernous injection must be done under sterile conditions. The site of injection is usually along the lateral aspect of the proximal third of the penis. Visible veins should be avoided. The side of the penis that is injected and the site of injection must be alternated. The injection site must be cleansed with an alcohol swab before injection.

The dose of Kai Tong® (alprostadil for injection) that is selected for self-injection treatment should provide the patient with an erection that is satisfactory for sexual intercourse and that is maintained for no longer than 1 hour. If the duration of erection is longer than 1 hour, the dose of Kai Tong® (alprostadil for injection) should be reduced. The lowest effective dose should be used at home. Self-injection therapy for use at home should be initiated at the dose that was determined in the physician's office. Dose adjustment may be required and should be made only after consultation with the physician.

Careful and continuous follow-up of the patient while in the self-injection program must be exercised. This is especially true for the initial self-injections, since adjustments in the dose of Kai Tong® (alprostadil for injection) may be needed. The recommended frequency of injection is no more than 3 times weekly, with at least 24 hours between each dose. The reconstituted Kai Tong® (alprostadil for injection) cartridge and needle are intended for single use only and should be discarded after use. The user should be instructed in the proper disposal of the needles and cartridges.

While on self-injection treatment, it is recommended that the patient visit the prescribing physician's office every 3 months. At that time, the efficacy and safety of the therapy should be assessed, and the dose of Kai Tong® (alprostadil for injection) should be adjusted, if needed.

The patient is instructed to follow the enclosed PATIENT INFORMATION pamphlet.

Preparation of Solution

The Kai Tong® (alprostadil for injection) injection device is used to reconstitute the single-dose, dual-chamber cartridge. The plunger is used to force the sterile 0.9% sodium chloride (1.075 mL) in one chamber into the chamber containing alprostadil. After reconstitution, the Kai Tong® (alprostadil for injection) injection device is used to administer the intracavernous injection of alprostadil. The reusable Kai Tong® (alprostadil for injection) injection device is for use only with the cartridges and needles included in the Kai Tong® (alprostadil for injection) Cartridge Packs.

Prepare the Kai Tong® (alprostadil for injection) solution immediately before use. Do not administer unless solution is clear. Do not add any drugs or solutions to the Kai Tong® (alprostadil for injection) solution. Discard any unused solution remaining in the cartridge. The reconstituted solution should not be stored.

The Kai Tong® (alprostadil for injection) cartridge contains a solid layer or lyophilized cake of dry white powder approximately 3/8” in thickness. A normal cake may appear cracked or crumbled. If the cartridge is damaged, the cake may shrink in size. Do not use the cartridge if it appears damaged or the cake is substantially reduced in size.

Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration. The reconstituted solution may initially appear cloudy due to small air bubbles. Do not use the solution if it remains cloudy, contains precipitates, or is discolored.

CAUTION: Do not reuse any solution remaining in the cartridge due to the possibility of bacterial contamination.

Administration

Kai Tong® (alprostadil for injection) is given as an intracavernous injection over a 5 to 10 second interval. See PATIENT INFORMATION for Kai Tong® (alprostadil for injection).

Stability

The single-dose, dual-chamber cartridge should be reconstituted only when it is certain that the patient is ready to administer the drug. The reconstituted drug solution should be used immediately after reconstitution. Any solution remaining in the cartridge should be discarded.

Use in Adults

Treatment of erectile dysfunction

Initiation of therapy: a medical professional should instruct each patient on the correct use of Kai Tong. The recommended starting dose is 500 micrograms.

Dosage may be increased in a stepwise manner (to 1000 micrograms), or decreased (to 250 or 125 micrograms) under medical supervision until the patient achieves a satisfactory response. After an assessment of the patient's skill and competence with the procedure, the chosen dose may then be prescribed for home use.

It is important for the patient to urinate before administration since a moist urethra makes administration of Kai Tong easier and is essential to dissolve the drug. To administer Kai Tong, remove the protective cover from the Kai Tong applicator, stretch the penis upward to its full length, and insert the applicator stem into the urethra. Depress the applicator button to release the medication from the applicator and remove the applicator from the urethra, (rocking the applicator gently prior to removal will ensure that the medication is separated from the applicator stem). Roll the penis between the hands for at least 10 seconds to ensure that the medication is adequately distributed along the wall of the urethra. If the patient feels a burning sensation it may help to roll the penis for an additional 30 to 60 seconds or until the burning subsides. The erection will develop within 5-10 minutes after administration and lasts approximately 30-60 minutes. After administration of Kai Tong, it is important to sit, or preferably, stand or walk for about 10 minutes while the erection is developing. More detailed information is given in the patient information leaflet. During home use, periodic checks of efficacy and safety are recommended.

Not more than 2 doses are recommended to be used in any 24-hour period, and not more than 7 doses are recommended to be used in a 7-day period. The prescribed dosage should not be exceeded.

Adjunct to other tests in the diagnosis and management of erectile dysfunction.

Kai Tong can be used as an adjunct in evaluating penile vascular function using Doppler duplex ultrasonography. It has been shown that a 500 microgram dose of Kai Tong has a comparable effect on penile arterial dilatation and peak systolic velocity flow to 10 microgram of alprostadil given by intracavernosal injection. At the time of discharge from the clinic, the erection should have subsided.

Use in the elderly

No adjustment for age is required.

Kai Tong is administered by direct intracavernous injection. A half inch, 27 to 30 gauge needle is generally recommended. The dose of Kai Tong should be individualised for each patient by careful titration under supervision by a physician.

The intracavernosal injection must be done under sterile conditions. The site of injection is usually along the dorsolateral aspect of the proximal third of the penis. Visible veins should be avoided. Both the side of the penis that is injected and the site of injection must be alternated; prior to the injection, the injection site must be cleansed with an alcohol swab.

To reconstitute Kai Tong using the prefilled diluent syringe: flip off the plastic cap from the vial, and use one of the swabs to wipe the rubber cap. Fit the 22 gauge needle to the syringe.

Inject the 1 ml of diluent into the vial, and shake to dissolve the powder entirely. Withdraw slightly more than the required dose of Kai Tong solution, remove the 22 gauge needle, and fit the 30 gauge needle. Adjust volume to the required dose for injection. Following administration, any unused contents of the vial or syringe should be discarded.

A. As an aid to aetiologic diagnosis.

Over 80% of subjects may be expected to respond to a single 20 micrograms dose of alprostadil. At the time of discharge from the clinic, the erection should have subsided entirely and the penis must be in a completely flaccid state.

B. Treatment

The initial dose of alprostadil in patients with erectile dysfunction of neurogenic origin secondary to spinal cord injury is 1.25 micrograms, with a second dose of 2.5 micrograms, a third of 5 micrograms, and subsequent incremental increases of 5 micrograms until an optimal dose is achieved. For erectile dysfunction of vasculogenic, psychogenic, or mixed aetiology, the initial dose is 2.5 micrograms. The second dose should be 5 micrograms if there is a partial response, and 7.5 micrograms if there is no response. Subsequent incremental increases of 5-10 micrograms should be given until an optimal dose is achieved. If there is no response to the administered dose, then the next higher dose may be given within 1 hour. If there is a response, there should be at least a 1-day interval before the next dose is given. The usual maximum recommended frequency of injection is no more than once daily and no more than three times weekly.

The first injections of alprostadil must be done by medically trained personnel. After proper training and instruction, alprostadil may be injected at home. If self-administration is planned, the physician should make an assessment of the patient's skill and competence with the procedure. It is recommended that patients are regularly monitored (e.g. every 3 months) particularly in the initial stages of self injection therapy when dose adjustments may be needed.

The dose that is selected for self-injection treatment should provide the patient with an erection that is satisfactory for sexual intercourse. It is recommended that the dose administered produces a duration of the erection not exceeding one hour. If the duration is longer, the dose should be reduced. The majority of patients achieve a satisfactory response with doses in the range of 5 to 20 micrograms. Doses of greater than 60 micrograms of alprostadil are not recommended. The lowest effective dose should be used.

Posology

The infusion is generally initiated at a rate of 0.05-0.1 micrograms/kg/min. The most experience has been with 0.1 micrograms/kg/min. After a therapeutic response (an increase in pO₂ in neonates with restricted pulmonary blood flow or an increase in systemic blood pressure and blood pH in neonates with restricted systemic blood flow) has been obtained, the infusion rate should be reduced to the lowest possible dosage that will maintain the desired response.

Doses lower than 0.05 microgram/kg/min (as low as 0.005 microgram/kg/min) alprostadil have been used successfully in neonates, specifically when transport of the infant is necessary. No comparative trials exist and the efficacy and safety of this approach when compared to the generally initiated dosage rate of 0.05-0.1 micrograms/kg/min is currently unclear.

Method of administration

For administration by intravenous drip or constant rate infusion pump.

In infants with lesions restricting pulmonary blood flow (blood is flowing through the ductus arteriosus from the aorta to the pulmonary artery), Prostin VR may be administered by continuous infusion through an umbilical artery catheter placed at or just above the junction of the descending aorta and the ductus arteriosus, or intravenously. The diluted solution should contain no more than 20 micrograms/ml alprostadil.

PARTICULAR CARE SHOULD BE TAKEN IN CALCULATING AND PREPARING DILUTIONS OF PROSTIN VR.