Sanofi teams up with Fulcrum on GSK's losmapimod

Sanofi is set to acquire development and certain marketing rights to Fulcrum Therapeutics' experimental drug losmapimod through a deal potentially exceeding $1 billion. Losmapimod, a selective p38α/β MAPK inhibitor, was originally in-licensed by Fulcrum from GSK in 2019. It is currently being evaluated in a Phase III clinical trial for the treatment of facioscapulohumeral muscular dystrophy (FSHD).

Burcu Eryilmaz, Sanofi’s global head of rare diseases, commented on the partnership, stating that it offers a significant opportunity to expand the company’s rare disease portfolio and potentially deliver the first approved treatment for FSHD. As part of the agreement, Sanofi will make an upfront payment of $80 million to Fulcrum. Additionally, Fulcrum stands to receive up to $975 million in further regulatory and sales-based milestone payments. The deal also includes tiered escalating royalties starting in the low-teens on sales outside the United States.

In earlier trials, specifically the Phase II ReDUX4 study, losmapimod showed a reduction in disease progression and improved functionality, including positive effects on upper extremity strength and other functional measures. The pivotal Phase III trial is expected to yield top-line results in the fourth quarter. Should these results be positive, Sanofi and Fulcrum plan to submit marketing applications in the United States, Europe, and Japan.

Under the terms of the agreement, Sanofi and Fulcrum will jointly share the future global development costs for the oral small molecule drug. Sanofi will receive exclusive commercialization rights outside the United States. Alex Sapir, Fulcrum’s CEO, mentioned that this deal aligns with Fulcrum's core strategy, allowing the company to concentrate on preparations for the commercialization of losmapimod within the US.

This collaboration between Sanofi and Fulcrum marks a significant step in the development of treatments for rare diseases. If successful, it could lead to the first approved therapy for FSHD, offering new hope for patients affected by this debilitating condition.