BioMarin paid $270 million for Inozyme’s BMN 401 in March 2025. The enzyme replacement therapy has now delivered a Phase 3 readout that calls that acquisition price into question.
The trial enrolled 27 children with ENPP1 deficiency, a rare genetic disorder where patients develop autosomal-recessive hypophosphatemic rickets type 2 and calcification of arteries, tendons and ligaments. BMN 401 cleared one of the two co-primary endpoints, showing a statistically significant increase in plasma inorganic pyrophosphate by Week 52 versus conventional therapy. The X-ray endpoint didn’t hold. BioMarin acknowledged “no positive trends” across secondary endpoints, including rickets severity, body growth and weight gain. The drug was well-tolerated with no new safety signals.
BioMarin paid $4 a share for Inozyme, more than twice its pre-deal closing price. That premium was a bet on clinical data. The data didn’t deliver.
The Inozyme deal was the first acquisition by James Sabry, the ex-Roche dealmaker BioMarin brought on as chief business officer in 2024. He’s since closed a $4.8 billion deal for Amicus Therapeutics, raising the stakes on BioMarin’s rare disease pipeline performance.
Chief R&D Officer Greg Friberg said the company is “actively evaluating these data to determine appropriate next steps” but stopped short of ending the program. Friberg cited high infant mortality rates and urgent unmet need in ENPP1 deficiency as reasons to keep looking.
BioMarin hasn’t announced a decision timeline for BMN 401.
Sarah Chen