Biogen buys midphase drug to challenge Roche for stroke market

Biogen is exercising its option to acquire an acute ischemic stroke candidate from TMS after getting a look at phase 2a data. The results persuaded Biogen to pay $18 million for a small molecule that may expand the time window in which thrombolytics can safely be used to clear clots.

TMS granted Biogen the option to buy the drug, TMS-007, in 2018 in return for $4 million upfront. The agreement gave Biogen the chance to buy the program for $18 million and up to $355 million in milestones. Having seen the results of a phase 2a study, Biogen has pulled the trigger on the deal and begun plotting further development of TMS-007.

The phase 2a study randomized 90 patients to receive TMS-007, a compound in the SMTP family, or placebo after presenting with symptoms of stroke. No patients in the TMS-007 arm had symptomatic intracranial hemorrhage (sICH), a side effect that deters physicians from using other drugs.

Earlier studies found the current thrombolytic therapy, tissue plasminogen activator, causes sICH in up to 6% of patients who receive the treatment up to nine hours after stroke onset. U.S. guidelines limit use of the drug, which is sold by Genentech as Activase, to patients who developed symptoms in the past 4.5 hours.

Participants in the TMS-007 trial received the thrombolytic up to 12 hours after the onset of stroke symptoms. The average time from symptom onset was 9.5 hours. If TMS-007 is efficacious that long after the onset of symptoms, it could enable more patients to receive effective treatment. 

The phase 2a generated early evidence that TMS-007 improves outcomes, notably by linking the drug to a significant improvement in the proportion of patients who were functionally independent at 90 days. Forty percent of patients who received TMS-007 had no significant disability, compared to 18% of people on placebo. Recanalization occurred in more patients in the TMS-007 cohort, too,

Biogen is now weighing up the next steps for the drug. The plans include global trials of a drug that has so far been studied in Japan, where TMS is based. Clinical success could unlock a useful market for Biogen. Activase and TNKase, another thrombolytic used to treat heart attacks, generated sales of CHF 1.3 billion ($1.4 billion) for Roche last year.