RT Journal Article T1 Pharmacogenetics of siponimod: A systematic review. A1 Diaz-Villamarin, Xando A1 Piñar-Morales, Raquel A1 Barrero-Hernandez, Francisco Javier A1 Antunez-Rodriguez, Alba A1 Cabeza-Barrera, Jose A1 Moron-Romero, Rocio K1 CYP2C9 K1 Mayzent K1 Multiple Sclerosis K1 Pharmacogenetics K1 Siponimod AB Multiple sclerosis is a chronic inflammatory neurological disease, and siponimod (Mayzent) is the first oral treatment option for adult patients with secondary progressive multiple sclerosis. We performed a systematic review of the pharmacogenetics of Siponimod, and we found that (430 C>T; rs1799853) and CYP2C9 * 3 (1075 A>C; rs1057910), both translated no-function alleles, have been related to a lower metabolism of siponimod by CYP2C9 enzyme. The FDA-approved drug label and EMA risk management plan for siponimod require testing patients for CYP2C9 genotype before treatment starts. The FDA drug label states that siponimod is contraindicated in patients carrying a CYP2C9 * 3/* 3 genotype, and a daily maintenance dose of 1 mg in patients with CYP2C9 * 1/* 3 and * 2/* 3 genotypes. The EMA reported the potential long-term safety implications in CYP2C9 poor metabolizer patients treated with this drug. Based on this systematic review we concluded that CYP2C9 SNPs influence on siponimod response might be stated by assessing not only CYP2C9 * 2 and CYP2C9 * 3 but other genetic variants resulting in CYP2C9 IM/PM status. CYP2C9 IM phenotype translated from the CYP2C9 * 2 genotype should be revised since it is contradictory compared to other CYP2C9 no-function alleles, and CYP2C9 * 2 might be excluded from PGx testing recommendation before treatment starts with siponimod since it is not translated into a therapeutic recommendation. PB Elsevier Masson YR 2022 FD 2022-08-08 LK http://hdl.handle.net/10668/22048 UL http://hdl.handle.net/10668/22048 LA en NO Díaz-Villamarín X, Piñar-Morales R, Barrero-Hernández FJ, Antúnez-Rodríguez A, Cabeza-Barrera J, Morón-Romero R. Pharmacogenetics of siponimod: A systematic review. Biomed Pharmacother. 2022 Sep;153:113536. DS RISalud RD Apr 11, 2025