Generic Name and Formulations:
Cysteamine bitartrate 25mg, 75mg; del-rel caps.
Indications for PROCYSBI:
Nephropathic cystinosis in patients ≥1yr of age.
Adults and Children:
<1yr: not established. Initiate immediately after diagnosis. Take on an empty stomach. Swallow whole with water or fruit juice (except grapefruit). May sprinkle contents of cap on 4oz of food (eg, applesauce or berry jelly) or mix in 4oz of fruit juice (except grapefruit); also, may administer via feeding tube after mixing with 4oz of applesauce. Cysteamine-naive: initiate at ⅙ to ¼ of the maintenance dose; (1–<6yrs): increase gradually in 10% increments allowing at least 2 weeks between dose adjustments; (≥6yrs): increase gradually over 4–6 weeks. Maintenance: 1.3g/m2/day, in 2 divided doses given every 12hrs; may further increase to achieve therapeutic target WBC cystine level. Max 1.95g/m2/day (if >50kg: max 1000mg every 12hrs). Goal of therapy: to maintain WBC cystine level <1nmol ½ cystine/mg protein (with mixed leukocyte assay). Switching from immediate-release cysteamine: give previous total daily dose of immediate-release caps. Dose titration, measuring WBC cystine levels: see full labeling.
Monitor for development of skin or bone lesions and interrupt dosing if occur; may restart at a lower dose. Permanently discontinue if severe skin rash develops. Consider lowering the dose if severe GI symptoms develop. Evaluate and monitor for CNS symptoms (eg, somnolence, encephalopathy, seizures); interrupt or adjust dose if severe, persist or progress. Monitor WBCs and alkaline phosphatase levels. Monitor for signs/symptoms of benign intracranial hypertension; permanently discontinue if confirmed. Pregnancy. Nursing mothers: not recommended.
Avoid alcohol. Concomitant drugs that increase gastric pH (eg, PPIs); monitor WBC cystine levels. Separate dosing of carbonate- or bicarbonate-containing products by at least 1hr before or 1hr after. May give concomitant Vit.D, thyroid hormone, or other electrolyte/mineral replacements for Fanconi syndrome.
Vomiting, nausea, abdominal pain, breath or skin odor, diarrhea, fatigue, rash, headache, gastroenteritis, electrolyte imbalance; Ehlers-Danlos-like syndrome, GI ulceration/bleeding, leukopenia, elevated alkaline phosphatase, pseudotumor cerebri, papilledema.
Caps 25mg—60; 75mg—250