risdiplam - Medications

EVRYSDI for oral solution and EVRYSDI tablets for oral use contain risdiplam, which is a survival of motor neuron 2 (SMN2)-directed RNA splicing modifier. The chemical name of risdiplam is 7-(4,7-diazaspiro[2.5]octan-7-yl)-2-(2,8 dimethylimidazo[1,2-b]pyridazin-6-yl)pyrido-4H-[1,2-a]pyrimidin-4-one. Risdiplam has a molecular weight of 401.46 g/mol. Risdiplam demonstrates pH-dependent aqueous solubility; the greatest solubility is at low pH, and solubility decreases with increasing pH. Risdiplam has a pKa 1 of 3.78 (base) and pKa 2 of 6.62 (base). The molecular formula of risdiplam is C 22 H 23 N 7 O and the chemical structure is shown below. EVRYSDI for oral solution is supplied as a powder in an amber glass bottle. Each bottle contains 60 mg of risdiplam. The inactive ingredients of EVRYSDI are: ascorbic acid, disodium edetate dihydrate, isomalt, mannitol, polyethylene glycol 6000, sodium benzoate, strawberry flavor, sucralose, and tartaric acid. The powder is constituted with purified water to yield 60 mg/80 mL (0.75 mg/mL) of risdiplam after constitution [see Dosage and Administration (2.4) ]. Each EVRYSDI tablet contains 5 mg of risdiplam. The inactive ingredients of EVRYSDI tablet are colloidal silicon dioxide, crospovidone, mannitol, microcrystalline cellulose, polyethylene glycol 3350, polyvinyl alcohol, sodium stearyl fumarate, strawberry flavor, talc, tartaric acid, titanium dioxide, and yellow iron oxide. Chemical Structure