BioMarin announces Phase 3 data for PALYNZIQ

BioMarin (BMRN) Pharmaceutical announced new data characterizing the efficacy and safety of PALYNZIQ for the treatment of adolescents with phenylketonuria, PKU, which were presented at the 15th International Congress of Inborn Errors of Metabolism, ICIEM, in Kyoto, Japan, Sept. 2-6, 2025. The Phase 3 PEGASUS study evaluating the efficacy and safety of PALYNZIQ in adolescents aged 12-17 demonstrated statistically significant blood phenylalanine lowering compared to diet alone. The study enrolled 55 adolescents, randomized to receive PALYNZIQ or diet alone. At baseline, the mean age was 14.3 years, mean blood Phe was 1026.4 micromol/L, and nearly half of participants had blood Phe levels above 1000 micromol/L. Notably, after the 72-week primary treatment phase, almost half of participants in the PALYNZIQ arm achieved reductions in blood Phe concentrations of 50% or more from baseline, with many reaching guideline-recommended and even normal Phe target levels.