Pfizer Withdraws Oxbryta (voxelotor) from Global Markets Due to Increased Risks of Death and Complications

The decision follows a comprehensive review of clinical data that suggested an imbalance in vaso-occlusive crises and fatal events associated with Oxbryta treatment. Vaso-occlusive crises are painful episodes commonly experienced by sickle cell patients. The European Medicines Agency had already initiated a review of Oxbryta after reports indicated a higher incidence of deaths in patients receiving the drug compared to those on a placebo. In light of these findings, Pfizer has informed regulatory authorities and is halting distribution and clinical studies of Oxbryta while further investigations are conducted. Despite the withdrawal, Pfizer does not expect any significant impact on its financial outlook for 2024.

Background on Oxbryta

Oxbryta was initially granted accelerated approval by the FDA in November 2019 for treating adults and pediatric patients aged 12 and older suffering from sickle cell disease. Pfizer acquired the drug through its $5.4 billion purchase of Global Blood Therapeutics in 2022. In the second quarter of 2024, Oxbryta reported sales of $92 million, reflecting a 20% increase year-over-year, prior to the withdrawal announcement.

Implications of the Withdrawal

The withdrawal of Oxbryta raises significant concerns about treatment options for patients with sickle cell disease, a condition characterized by painful crises and various complications. The move reflects ongoing challenges in the development and approval of therapies for complex diseases, emphasizing the necessity for rigorous safety evaluations.