Santhera licences vamorolone rights to Catalyst Pharmaceuticals

Pratteln-based Santhera Pharmaceuticals Holding got a US$90m upfront payment from Catalyst Pharmaceuticals Inc for the Northern America vamorolone licence and could cash in additional US4$141m plus royalties, if the orphan drug gets FDA and Health Canada approval in Q4/23 as expected by the Swiss company. From the upfront payment, US$75m is in cash and US$15m is an equity investment through the purchase of 14,146,882 treasury shares at a price of CHF 0.9477 per share. A US$10m milestone will be paid upon U.S. FDA approval of vamorolone in Duchenne muscular dystrophy (DMD).  Potential sales milestones could sum up to US$105m. The licence agreement covers commercialisation of vamorolone in DMD and rights to all potential future indications in North America. According to the deal conditions, Catalyst will pay Santhera up to low-teen percentage royalties and will assume corresponding third-party royalty obligations on vamorolone sales in Northern America

While Santhera expects EU market authorisation and commercialization of vamorolone in DMD at the end of this year, and plans to expand to further indications first on its own further, Santhera and Catalyst intend to collaborate on joint clinical development and funding of vamorolone for additional indications.  

Dario Eklund, Chief Executive Officer of Santhera, commented: “Duchenne muscular dystrophy is a devastating condition. Everyone at Santhera has been working diligently to advance vamorolone in order to make this important treatment option available to patients. 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.”

In Europe, Santhera plans to commercialise vamorolone in key  markets including Germany, France, UK, Italy, Spain, Benelux, and 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.

For certain countries, where Santhera chooses not to market vamorolone directly, including certain European countries and Japan, it has granted Catalyst a right of first negotiation in partnering discussions. The new drug application (NDA) for vamorolone in DMD is under review in the U.S. by FDA, which has set October 26, 2023 as the Prescription Drug User Fee Act (PDUFA) date for its regulatory decision on approval. In Europe, the review of the marketing authorization application (MAA) for vamorolone by the European Medicines Agency (EMA) is ongoing. An opinion from the Committee for Medicinal Products for Human Use (CHMP) is expected in Q3-2023, followed by an approval decision by the European Commission (EC) in late 2023. In the UK, a corresponding MAA is under review by the Medicines and Healthcare products Regulatory Agency (MHRA). Subject to approvals, vamorolone could be launched in both the first EU countries and the U.S. in late 2023 and early in the first quarter 2024, respectively.

For indications in addition to DMD, Santhera and Catalyst will establish a joint steering committee (JSC) to undertake the joint clinical development of vamorolone for global indications, in which both parties would participate in the development process and funding.

Duchenne muscular dystrophy (DMD) is a rare inherited X-chromosome-linked inflammatory disease leading to fibrosis and degeneration of muscle, which mostly affects males. Major milestones in the disease are the loss of ambulation, the loss of selffeeding, the start of assisted ventilation, and the development of cardiomyopathy. 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. Vamolorone is a delta-9,11 glucocorticoid analogue, being developed by ReveraGen Biopharma (formerly Validus Biopharma), which will get US$26m upon US approval.