BioMarin continues pipeline clearout by halting preclinical gene therapy for heart condition

After BioMarin conducted a spring clean of its pipeline in April, the company has decided that it also needs to offload a preclinical gene therapy for a condition that causes heart muscles to thicken.

The therapy, dubbed BMN 293, was being developed for myosin-binding protein C3 (MYBPC3) hypertrophic cardiomyopathy. The condition can be treated using beta blocker medications, but BioMarin had set out to treat the symptomatic heart disease using just a single dose.

The company shared (PDF) preclinical data from BMN 293 at an R&D Day in September 2023, where it said that the candidate had demonstrated a functional improvement in MYBPC3 in mice. Mutations in MYBPC3 are the most common cause of hypertrophic cardiomyopathy.

At the time, BioMarin was still on track to take BMN 293 into human trials in 2024.

But in this morning’s second-quarter earnings press release, the company said it recently decided to discontinue development.

“Applying its focused approach to investing in only those assets that have the highest potential impact for patients, the time and resources anticipated to bring BMN 293 through development and to market no longer met BioMarin's high bar for advancement,” the company explained in the release.

The company had already whittled down its R&D pipeline in April, ditching clinical-stage therapies aimed at hereditary angioedema and metabolic dysfunction-associated steatohepatitis (MASH). Two preclinical assets aimed at different heart conditions were also scrapped.

All this means that BioMarin’s attention is now spread across three key candidates. Enrollment in a phase 1 trial of BMN 351, a next-generation oligonucleotide for Duchenne muscular dystrophy, has completed and data are due by the end of the year. A first-in-human study of the oral small molecule BMN 349, for which BioMarin has ambitions to become a best-in-class treatment for Alpha-1 antitrypsin deficiency (AATD)-associated liver disease, is due to kick off later in 2024.

There’s also BMN 333, a long-acting C-type natriuretic peptide for multiple growth disorder, which isn’t likely to enter the clinic until early 2025.

Meanwhile, BioMarin also unveiled a more limited rollout plan for its hemophilia A gene therapy Roctavian. Despite a European approval in 2022 and a U.S. nod last year, uptake has been slow, with only three patients treated in the U.S. and two in Italy in the second quarter—although the hefty price tag meant the drug still brought in $7 million in revenue.

In order to ensure “long-term profitability,” the company said it would limit its focus for Roctavian to just the U.S., Germany and Italy. This would likely save around $60 million a year from 2025 onwards.