Ex-US tolebrutinib expansion comes under the spotlight
Sanofi must have hoped that a second-quarter beat and raise would be enough to silence doubters. But today’s earnings call was dominated by questions about tolebrutinib, the group’s troubled oral BTK inhibitor for multiple sclerosis, which recently went on partial US clinical hold. The group has enrolled nearly 200 patients outside the US since protocol changes were made to reduce liver injury risk (the problem that led to the pause), and hopes that timelines will accordingly remain unchanged. John Reed, head of R&D, said pivotal Gemini studies in relapsing disease were still on track to read out in late 2023. Whether inclusion of more ex-US patients results in a dataset sufficiently representative of a US population is now the question, and Mr Reed said the company was “sufficiently covered” in terms of US patients currently enrolled. But geography has become a live issue given the FDA’s stance on data it deems not generalisable to the US, notably from China. Sanofi hopes to get the hold lifted by the fourth quarter – a crucial timeline if more US subjects do, after all, have to be enrolled.