Catalyst Acquires North American Rights to Santhera’s DMD Therapy for $231 Million Plus Royalties

Rare Daily Staff
Santhera Pharmaceuticals said it has signed an exclusive license and collaboration agreement with Catalyst Pharmaceuticals for its experimental Duchenne muscular dystrophy therapy vamorolone in North America for up to $231 million including an equity investment.

Under the terms of the agreement, Santhera will grant Catalyst exclusive commercialization rights to vamorolone in the United States, Canada, and Mexico. At closing, Santhera will receive an upfront cash payment of $75 million. In addition, Catalyst will make an equity investment of $15 million through the purchase of 14.1 million treasury shares at a price of $1.06 (CHF 0.9477) per share, the ten-day, volume-weighted average price ending two days prior to signing of the agreement. The shares are subject to a six-month post-closing lock-up and standstill. The proceeds from the equity sale will support phase 4 studies in DMD and joint development of additional indications.

“We believe Catalyst is well placed to maximize the value of vamorolone and, subject to regulatory approval, ensure patients in North America receive this transformational therapy as quickly as possible. Catalyst has a track record of success in the rare disease and neuromuscular space and is our commercial partner of choice for North America with an established infrastructure and commitment to patients,” Dario Eklund, CEO of Santhera. “As part of this agreement, Santhera benefits from upfront, milestone and royalty payments which allows us to focus on the commercial roll-out of vamorolone in DMD and future other indications in Europe.”

Duchenne muscular dystrophy (DMD) is a rare inherited X-chromosome-linked disease, which almost exclusively affects males. DMD is characterized by inflammation which is present at birth or shortly thereafter. Inflammation leads to fibrosis of muscle and is clinically manifested by progressive muscle degeneration and weakness. People with the condition can lose the ability to walk, feed themselves, or breathe without assistance. They also can develop disease of the heart muscle. DMD reduces life expectancy to before the fourth decade due to respiratory and/or cardiac failure. Corticosteroids are the current standard of care for the treatment of DMD.

Vamorolone is an experimental drug candidate with a mode of action based on binding to the same receptor as glucocorticoids but modifying its downstream activity. It is considered a dissociative anti-inflammatory drug. This mechanism has shown the potential to “dissociate” efficacy from steroid safety concerns and therefore vamorolone could emerge as an alternative to existing corticosteroids, the current standard of care in children and adolescent subjects with DMD.

In the pivotal VISION-DMD study, vamorolone met the primary endpoint Time to Stand velocity versus placebo at 24 weeks of treatment and showed a good safety and tolerability profile. The most commonly reported adverse events versus placebo from the VISION-DMD study were cushingoid features, vomiting, and vitamin D deficiency. Adverse events were generally of mild to moderate severity.

The new drug application for vamorolone in DMD is under review in the U.S. Food and Drug Administration, which is expected to act on the application by October 26, 2023. In Europe, the review of the marketing authorization application for vamorolone by the European Medicines Agency is ongoing. An opinion from the Committee for Medicinal Products for Human Use is expected in the third quarter of 2023, followed by an approval decision by the European Commission in late 2023. In the United Kingdom, a corresponding marketing application is under review by the Medicines and Healthcare products Regulatory Agency. Subject to approvals, vamorolone could be launched in both the first EU countries in late 2023 and the United States in the first quarter 2024.

The closing of the transaction is expected to occur early in the third quarter 2023, subject to customary conditions and regulatory clearances in the United States. In Europe, Santhera plans to commercialize vamorolone in key geographies including Germany, France, UK, Italy, Spain, Benelux. It said it will seek partners for commercialization in all other countries. Market access, the build-up of a core organization and stakeholder engagement activities in these priority countries are ongoing.

Photo: Dario Eklund, CEO of Santhera