Ipsen has announced the approval of its drug Sohonos (palovarotene) for the treatment of the ultra-rare genetic disorder fibrodysplasia ossificans progressiva (FOP), issued by Health Canada, marking the first global approval of the drug.
The disorder is estimated to affect the lives of 1.36 per million people, with the number of confirmed cases varying from country to country.
The treatment is administered as an oral selective retinoic-acid receptor gamma (RARγ) agonist indicated to reduce the production of heterotopic ossification – new bone formation – in adults and children. Specifically, the treatment can be used for female patients with FOP aged eight years and above and for male patients with FOP aged ten years and above. Sohonos has been given the green light for patients diagnosed with both chronic cases of FOP and also for flare-ups.
FOP is a condition characterised by heterotopic ossification – the forming of new bone outside of the normal skeleton, eg, in soft connective tissues. What can follow is a painful development of soft tissue swelling or flare-ups. The latter is a common and substantial contributor to the formation of new bone. Despite this, new bone also has the ability to form without a flare-up episode. Once the bone is formed, the result is irreversible, leading to a loss of mobility and a shortened life expectancy.
Dr Howard Mayer, executive vice president and head of research and development, Ipsen, commented: “FOP is a progressive and debilitating condition which has such a profound impact on patients and their families. Until today, there was no approved medicine and we are proud to bring this important new medicine to the FOP community.”
Ipsen had previously announced the withdrawal of its New Drug Application (NDA) to the US Food and Drug Administration (FDA) for palovarotene in August 2021.
The initial withdrawal followed an ongoing dialogue with the FDA, after it was recognised that additional evaluations and data analyses collected from Ipsen’s phase 3 MOVE and FOP programmes would be required in order to further progress and finish the review process. It was agreed by Ipsen and the FDA that the completion of the process would not be possible to finish within the parameters set by the NDA review cycle. As a result, Ipsen confirmed its withdrawal with the FDA and indicated that it would resubmit at a future date.
Ipsen aims to file in the US in H1 2022 and is currently in communication with other regulatory bodies worldwide.