"By Megan Brooks
Medscape Medical News
The European Medicines Agency (EMA) Committee for Medicinal Products for Human Use (CHMP) has recommended approval of tolvaptan (Jinarc, Otuska) to slow progression of cyst developmen"...
CYSTAGON® (cysteamine bitartrate) is indicated for the management of nephropathic cystinosis in children and adults.
DOSAGE AND ADMINISTRATION
For the management of nephropathic cystinosis, cysteamine therapy should be initiated promptly once the diagnosis is confirmed (i.e., increased white cell cystine).
New patients should be started on ¼ to 1/6 of the maintenance dose of CYSTAGON® (cysteamine bitartrate) . The dose should then be raised gradually over four to six weeks to avoid intolerance.
The recommended CYSTAGON® (cysteamine bitartrate) maintenance dose for children up to age 12 years is 1.30 grams/m2/day of the free base, given in four divided doses. Intact CYSTAGON® (cysteamine bitartrate) capsules should not be administered to children under the age of approximately six years due to the risk of aspiration. CYSTAGON® (cysteamine bitartrate) capsules may be administered to children under the age of approximately six years by sprinkling the capsule contents over food. Patients over age 12 and over 110 pounds weight should receive 2.0 grams/day, divided four times daily.
If a dose is missed, it should be taken as soon as possible. If it is within two hours of the next dose, skip the missed dose and go back to the regular dosing schedule. Do not double dose.
When CYSTAGON® (cysteamine bitartrate) is well tolerated, the goal of therapy is to keep leukocyte cystine levels below 1 nmol/½ cystine/mg protein five to six hours following administration of CYSTAGON® (cysteamine bitartrate) . Patients with poorer tolerability still receive significant benefit if white cell cystine levels are below 2 nmol/½ cystine/mg protein. The CYSTAGON® (cysteamine bitartrate) dose can be increased to a maximum of 1.95 grams/m2/day to achieve this level. The dose of 1.95 grams/m2/day has been associated with an increased rate of withdrawal from treatment due to intolerance and an increased incidence of adverse events.
Cystinotic patients taking cysteamine hydrochloride or phosphocysteamine solutions may be transferred to equimolar doses of CYSTAGON® (cysteamine bitartrate) capsules.
The recommended maintenance dose of 1.30 grams/m2/day can be approximated by administering CYSTAGON® (cysteamine bitartrate) according to the following table, which takes surface area as well as weight into consideration.
| Weight in
| mg of Cysteamine Free Base
Every 6 Hours
Patients over age 12 and over 110 pounds should receive 2.0 grams/day given in four divided doses as a starting maintenance dose. This dose should be reached after 4 to 6 weeks of incremental dosage increases as stated above. The dose should be raised if the leukocyte cystine level remains > 2 nmol/½ cystine/mg/protein.
Leukocyte cystine measurements, taken 5 to 6 hours after dose administration, are recommended for new patients after the maintenance dose is achieved. Patients being transferred from cysteamine hydrochloride or phosphocysteamine solutions to capsules should have their white cell cystine levels measured in 2 weeks, and thereafter every 3 months to assess optimal dosage as described above.
If CYSTAGON® (cysteamine bitartrate) is poorly tolerated initially due to gastrointestinal tract symptoms or transient skin rashes, therapy should be temporarily stopped, then re-instituted at a lower dose and gradually increased to the proper dose.
CYSTAGON® (cysteamine bitartrate) Capsules are hard gelatin capsules which provide 50 mg or 150 mg of cysteamine free base as cysteamine bitartrate:
CYSTAGON® (cysteamine bitartrate) Capsules, 50 mg are white, opaque capsules printed with CYSTA 50 on the body and MYLAN on the cap. They are available as follows:
NDC 0378-9040-05 bottles of 500 capsules
CYSTAGON® (cysteamine bitartrate) Capsules, 150 mg are white, opaque capsules printed with CYSTAGON (cysteamine bitartrate) 150 on the body and MYLAN on the cap. They are available as follows:
NDC 0378-9045-05 bottles of 500 capsules
Store at 20° to 25°C (68° to 77°F). [See USP for Controlled Room Temperature.]
Protect from light and moisture.
Dispense in a tight, light-resistant container as defined in the USP using a child-resistant closure.
Mylan Pharmaceuticals Inc.,Morgantown, WV 26505
REVISED JUNE 2007
FDA rev date: 6/6/2007
Last reviewed on RxList: 6/26/2007
Additional Cystagon Information
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