Pfizer said that it is voluntarily withdrawing all lots of its sickle cell disease (SCD) drug Oxbryta (voxelotor) from global markets.
The New York-based drug major is also ending all active voxelotor clinical trials and expanded access programmes.
This decision comes after a review of the totality of clinical data. Pfizer found that the risks of Oxbryta now outweigh its overall benefits for approved SCD patients.
The findings also signalled an imbalance in vaso-occlusive issues and fatal events, which called for further evaluation.
Pfizer has informed regulatory authorities about these findings and withdrawal decision.
The drug maker will halt distribution and studies while it further assesses the available data and investigates the issues.
Oxbryta is a once-daily oral therapy. The drug was added to Pfizer’s portfolio through the company’s $5.4bn acquisition of US-based Global Blood Therapeutics in 2022.
In 2019, the US Food and Drug Administration (FDA) granted accelerated approval for voxelotor in SCD for adults and children aged 12 and older. The approval was expanded in December 2021 to include patients aged four and older in the US.
In Europe, the SCD therapy received Priority Medicines (PRIME) status and was given the orphan medicinal product designation.
In February 2022, the European Commission (EC) approved Oxbryta for treating haemolytic anaemia caused by SCD in patients 12 and older.
Since its launch, the drug has been approved in over 35 countries.
Pfizer worldwide medical and safety head and chief medical officer Aida Habtezion said: “Our primary concern is for patients who suffer from SCD, which remains a very serious and difficult-to-treat disease with limited treatment options.
“We advise patients to contact their physicians to discuss alternative treatment while we continue to investigate the findings from our review of the data.”
The company does not expect this withdrawal to affect its financial guidance for the full year of 2024.