By Ludwig Berger
(Reuters) – Sanofi Nasdaq:NASDAQ:NASDAQ:MSN’S most advanced multiple sclerosis drug failed to meet the main goal of two late-stage trials to treat recurrent forms of the disease, dimming the prospects for a broad class of drugs.
The French drugmaker said on Monday that two phase 3 trials showed that its experimental daily tablet tolbrutinib was no better than the multiple sclerosis drug Aubagio at reducing relapse rates in a very common form of multiple sclerosis characterized by isolated attacks followed by temporary improvements.
In an attempt to mitigate the setback for Sanofi, the company said a separate, third, late-stage trial showed that tolbrutinib met the main goal of treating a progressive — or steadily worsening — form of multiple sclerosis, which is less common and currently incurable.
In that trial, Sanofi’s candidate drug slowed the progression of disability when compared to a placebo, an inactive fake drug.
“Tolbrutinib represents an unprecedented achievement as a potential first-time treatment option in the disease with meaningful clinical benefit in disability accumulation,” said Homan Ashrafian, MD, head of research and development.
The company added that it will discuss these results with regulatory authorities, with the aim of submitting an application for approval by the end of 2024.
Sanofi is looking to exploit several opportunities in multiple sclerosis, a debilitating neurological disease, to offset revenue losses after the recent expiration of patent protection for Aubagio, as part of efforts to become a force in anti-inflammatory drugs.
CEO Paul Hudson (NYSE:) has been trying to restore investor confidence in its drug pipeline since he unexpectedly abandoned 2025 margin targets last October to boost spending on drug development.
The company’s shares have rebounded somewhat in recent months thanks to the launch of new drugs, including Bifortus to protect children from common respiratory infections.
Tolbrutinib, from $3.7 billion acquisition Principles of Biopharmaceuticals (NASDAQ:) In 2020, it belongs to a class of compounds known as Bruton’s tyrosine kinase (BTK) inhibitors, which have also attracted major pharmaceutical companies. Novartis (SIX:), Roche and Merck KGaA.
These drugs are designed to selectively block the harmful autoimmune reaction behind MS for a more targeted approach than standard immunosuppressive drugs.
However, investors remained concerned about revenue prospects due to a potential link to liver damage and uncertain efficacy.
In 2022, concerns about liver damage led to a halt in enrollment of new patients in three Sanofi studies of tolbrutinib that were still recruiting at the time.
Sanofi said Monday that the liver safety is consistent with previous studies, and more data is due out on Sept. 20.
Merck KGaA’s BTK inhibitor has also been under scrutiny over liver safety. In December, the drug failed to meet its efficacy target in a clinical trial in multiple sclerosis patients, a blow to the German company’s growth ambitions.
Roche’s Genentech is still in the race, but concerns about the safety of its BTK inhibitors also surfaced in November. Rival Novartis announced that its BTK candidate showed no signs of liver damage. Sanofi on Monday only provided brief summaries of its GEMINI I & II trials for relapsing-remitting MS and its HERCULES trial for advanced MS.
Details will be presented at the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) conference in Copenhagen on September 20, she said.
Sanofi added that another phase 3 study known as PERSEUS in another progressive form of MS is ongoing and results are expected in 2025.