Biogen has entered into a partnership with Stoke Therapeutics to co-develop and commercialize zorevunersen, an experimental treatment for Dravet syndrome, outside the U.S.

Under this agreement, Biogen will hold exclusive rights to market zorevunersen in regions excluding the United States, Canada, and Mexico.

The deal includes an upfront payment of $165 million to Stoke, along with potential milestone payments that could total up to $385 million.

This initial payment will fully fund a pivotal Phase 3 clinical trial for zorevunersen, which is scheduled to begin in the second quarter of 2025.

Results from the Phase 3 EMPEROR study are anticipated in the latter half of 2027.

Zorevunersen has demonstrated the potential to significantly reduce convulsive seizure frequency and improve cognitive and behavioral outcomes over time.

This treatment targets the SCN1A gene mutation, which is present in over 85% of Dravet syndrome cases, utilizing antisense oligonucleotide technology.

This partnership highlights the growing interest in innovative therapies for serious neurological conditions as pharmaceutical companies seek to expand their portfolios.

The collaboration is expected to enhance Biogen's pipeline in rare diseases and neurology, providing a potential growth avenue as the company aims to recover later in the decade.

Despite this partnership, Stoke Therapeutics retains full ownership of zorevunersen in the U.S. and North America.

Biogen's experience with RNA-targeted therapies, particularly from its previous collaboration with Ionis Pharmaceuticals, positions it well for this venture.

Overall, the partnership provides Stoke with essential financial backing to advance zorevunersen through its critical Phase 3 trials.