Pfizer has announced the voluntary withdrawal of all lots of OXBRYTA (voxelotor), a treatment for sickle cell disease (SCD), from global markets. The company will also discontinue all ongoing voxelotor clinical trials and expanded access programs worldwide.
This decision follows the release of comprehensive clinical data indicating that the risks associated with OXBRYTA may outweigh its benefits for the approved patient population. The findings revealed an imbalance in vaso-occlusive incidents and fatal events, prompting the need for further evaluation.
Pfizer has notified regulatory authorities about these findings and its choice to cease the distribution of OXBRYTA and halt current clinical studies. The company plans to conduct a thorough review of the available data and investigate the recent findings.
OXBRYTA is an oral treatment taken once daily, designed to enhance the oxygen affinity of hemoglobin to prevent the polymerization of sickle hemoglobin. This process is vital in averting the sickling and destruction of red blood cells, which leads to hemolysis and hemolytic anemia—common complications in SCD patients.
Initially, the US Food and Drug Administration (FDA) granted accelerated approval for OXBRYTA in 2019 for treating SCD in adults and children aged 12 and older. In December 2021, this approval was extended to include patients as young as four years old.
In Europe, OXBRYTA received priority medicines (PRIME) designation and orphan medicinal product status for SCD treatment. The European Commission authorized the marketing of OXBRYTA in February 2022 for treating hemolytic anemia due to SCD in both adults and pediatric patients aged 12 and above, either as a standalone treatment or alongside hydroxycarbamide (hydroxyurea).
The therapy is approved in over 35 countries worldwide. Aida Habtezion, Pfizer’s Chief Medical Officer and Head of Worldwide Medical and Safety, emphasized, “The safety and well-being of patients are our top priority. We believe this action is in the best interest of patients.”
She urged SCD patients to consult with their physicians regarding alternative treatment options as the company continues to investigate the data review findings.