The European Medicines Agency will meet on Thursday to discuss Oxbryta — the sickle cell treatment Pfizer inherited in its $5.4 billion acquisition of Global Blood Therapeutics — following patient deaths in two trials.
The agency announced in July that it was conducting a review of Oxbryta, also known as voxelotor, after one clinical trial in patients at a higher risk of stroke resulted in a higher number of deaths in the treatment arm compared to placebo. Another study in leg ulcers showed a “higher than anticipated” number of deaths. Regulators said at the time that no evidence tied Oxbryta to the deaths, noting that some may have been caused by infections such as malaria.
Treatment with Oxbryta was halted in both studies, the EMA said in July. The study in patients at high stroke risk enrolled 236 participants in Egypt, Ghana, Kenya, Nigeria, Oman, Saudi Arabia, the US and the UK. As of July 29, eight deaths had occurred in the treatment group, compared to two in the placebo arm.
The study on leg ulcers recruited 88 patients from Brazil, Kenya and Nigeria. Eight deaths had occurred in the open-label portion of the study as of July 29, according to the EMA.
Pfizer acquired Oxbryta in 2022, when it closed a $5.4 billion deal to buy out GBT. The company declined to comment ahead of the meeting.
Editor’s Note: This story has been updated to reflect that Pfizer declined to comment.