Comparative Pharmacology
Head-to-head clinical analysis: CYSTADROPS versus CYSTARAN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CYSTADROPS versus CYSTARAN.
CYSTADROPS vs CYSTARAN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Cysteamine depletes cystine within lysosomes by forming a cysteine-cysteamine mixed disulfide that exits via the lysosomal cystine transporter, reducing cystine accumulation in cystinosis.
Cystaran (cysteamine ophthalmic solution) acts by depleting cystine within corneal epithelial cells. Cysteamine reduces cystine accumulation by converting cystine to cysteine, which is then transported out of lysosomes via the cysteine transporter. This lowers corneal cystine crystal deposition in cystinosis patients.
Cystadrops (cysteamine hydrochloride) ophthalmic solution: 1 drop in each eye every 4 hours during waking hours.
Instill 1 drop in each eye every 4 hours while awake.
None Documented
None Documented
Terminal elimination half-life is approximately 5 hours. No significant accumulation with twice-daily dosing in patients with normal renal function.
Terminal elimination half-life is approximately 3.3 hours in adults with normal renal function. Clinically, this supports twice-daily dosing for ophthalmic use, as systemic accumulation is not significant.
Primarily renal as unchanged drug. Approximately 90% of the administered dose is excreted unchanged in urine within 24 hours. Biliary/fecal elimination is negligible (<5%).
Renal (primarily as unchanged drug); approximately 67% of a dose is excreted unchanged in urine within 24 hours. Biliary/fecal elimination is negligible (<2%).
Category C
Category C
Ophthalmic Cystine Depletion Agent
Ophthalmic Cystine Depletion Agent