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Cystagon (Mercaptamine)

Mylan · FDA-approved active Small molecule Quality 55/100

Cystagon works by binding to cystine and forming a disulfide bond, effectively removing cystine from the body.

At a glance

Generic nameMercaptamine
SponsorMylan
Drug classCystine Depleting Agent
ModalitySmall molecule
Therapeutic areaMetabolic
PhaseFDA-approved
First approval1994

Mechanism of action

Mechanism of Action. Cystinosis is an autosomal recessive inborn error of metabolism in which the transport of cystine out of lysosomes is abnormal; in the nephropathic form, accumulation of cystine and formation of crystals damage various organs, especially the kidney, leading to renal tubular Fanconi Syndrome and progressive glomerular failure, with end stage renal failure by the end of the first decade of life. In four studies of cystinosis patients before cysteamine was available, renal death (need for transplant or dialysis) occurred at median age of less than 10 years. Patients with cystinosis also experience growth failure, rickets, and photophobia due to cystine deposits in the cornea. With time most organs are damaged, including the retina, muscles and central nervous system.Cysteamine is an aminothiol that participates within lysosomes in thiol-disulfide interchange reaction converting cystine into cysteine and cysteine-cysteamine mixed disulfide, both of which can exit the l

Approved indications

Common side effects

Key clinical trials

Patents

PatentExpiryType

Primary sources

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SourceUsed for
FDA labelMechanism, indications, dosing, boxed warnings, drug interactions
ClinicalTrials.govTrial enrolment, design, endpoints, results
FDA Orange BookPatents + exclusivity

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