Acute ischemic stroke is typically treated with drugs that dissolve blood clots but these therapies bring the risk of a potentially deadly complication. An experimental drug from Japan-based TMS Co. met the goals of a mid-stage study without any signs of the dangerous side effect and Biogen has paid $18 million to acquire the compound.
The acquisition of the drug, TMS-007, comes nearly three years after Biogen paid $4 million up front for an exclusive option to license the compound. The Cambridge, Massachusetts-based neuroscience company said Wednesday that it is evaluating the next steps for the drug, including plans for global clinical trials.
TMS-007 is a small molecule that is a tissue plasminogen activator (tPA), which means it activates an enzyme involved in dissolving blood clots. There are other drugs for stroke that work this way but Biogen says TMS-007 has a novel mechanism of action and could potentially block inflammation at the site of the clot. In addition to those features, Biogen said the drug could offer an extended treatment window compared to currently approved stroke therapies.
The potentially deadly complication associated with clot-busting drugs, symptomatic intracranial hemorrhage (sICH), involves bleeding in the brain. According to the American Heart Association, in the time window of up to nine hours after a stroke, this complication has occurred in up to 6% of patients who have received tPA treatments in controlled clinical studies.
TMS evaluated its drug in a placebo-controlled, dose-ascending Phase 2a study enrolling 90 patients in Japan. The main goal was to evaluate safety, as assessed by the incidence of sICH worsening as measured according to a scale that assesses stroke severity. According to Biogen, there were no events reported in patients who received the TMS drug. In the group given the placebo, the incidence of events was 3%.
Biogen said that the TMS drug also met secondary goals assessing functional independence of patients. At 90 days, 40% of patients who received the drug achieved scores of 0 or 1 on the modified Rankin scale, an assessment of stroke patients’ ability to perform the tasks of daily living in which a higher score conveys greater disability. Biogen said it expects final results from the Phase 2a study will be reported at a future scientific forum.
Biogen’s pipeline includes another stroke drug candidate, glibenclamide. The intravenously infused drug is in pivotal testing in large hemispheric infarction (LHI), a severe form of ischemic stroke. But Biogen has said that this Phase 3 study has been delayed because the drug must be administered in hospitals, which are affected by staffing issues to respond to the pandemic and Covid-19 travel restrictions that affect patients.
In exercising the option for TMS-007, Biogen now assumes responsibility for all the costs and expenses related to developing, manufacturing, and commercializing the drug, if it’s approved. Depending on the drug’s progress, Biogen could pay TMS up to $335 million in development and commercialization milestones.
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