Words by Isabel O’Brien
It’s been both a good and bad week for French pharmaceutical company Sanofi, as their most advanced multiple sclerosis drug candidate, tolebrutinib, received mixed trial results.
The drug failed to meet its primary endpoints in two Phase III trials into a relapsing form of the condition. However, it performed well in a third late-stage trial into progressive MS, a less common and currently untreatable form of the disease. Importantly, this study showed that tolebrutinib slowed the progression of disability in patients.
Dr Houman Ashrafian, Head of Research & Development, Sanofi, was enthusiastic about the results, saying the drug was “an unprecedented breakthrough as a potential first-in-disease treatment option”. He also noted that the accumulation of disability is “the greatest unmet medical need” for people with non-relapsing secondary progressive MS, the form of MS for the drug shows promise.
Following the news, Sanofi’s shares went by up to 4.5%, reaching a ten-month high. Analysts have noted that despite the setbacks, tolebrutinib could still represent a 1-2bn (USD) opportunity for the company, possibly de-risked by its potential in the other indication.
Sanofi plans to discuss these results with regulators and aims for approval by the end of 2024. The company is also exploring other MS treatments to offset revenue losses from their now off-patent MS drug teriflunomide and to strengthen its position in the anti-inflammatory drug market.
Tolebrutinib, part of the Bruton’s tyrosine kinase (BTK) inhibitor class, faces competition from Novartis, Roche and Merck. Sanofi will present detailed trial results at a medical conference in Copenhagen on 20 September. Additional studies, including the ongoing PERSEUS trial in another progressive MS form, are expected to yield results by 2025. Sanofi is also developing another MS candidate, frexalimab, which is in earlier stages.
