An Important Message From Pfizer

We're reaching out to share an important update on Oxbryta^® (voxelotor)*, as part of our ongoing commitment to keeping the sickle cell community informed.

In April, we shared that Pfizer was continuing discussions with the U.S. Food and Drug Administration (FDA) to potentially make Oxbryta available again for people living with sickle cell. Over the past two years, Pfizer comprehensively analyzed the totality of the final clinical trial, registry (real world), and post-marketing safety and efficacy data for voxelotor and provided this information to FDA for review and continued discussion.

Based on recent engagement with the FDA and their assessment of these data, it is clear that there is not a viable path to make Oxbryta available again in the U.S. We understand that this news is disappointing and we are deeply saddened by this outcome, especially given the significant unmet needs for people living with sickle cell.

We want to make it clear that Pfizer will stay present and actively engaged with the sickle cell community. This includes continuing our ongoing research efforts for osivelotor, as we work to bring forward medicines for people living with sickle cell.

We also remain committed to transparency and will continue sharing Oxbryta data as it is published, including clinical trial data publications as they are accepted in medical journals and plain language summaries that make the findings accessible to sickle cell warriors, caregivers, and community organizations. We are confident that learnings acquired in the Oxbryta program will continue to benefit future sickle cell research and innovation.

We are incredibly grateful to those in the sickle cell community for their support, time and engagement, including individuals living with sickle cell, caregivers, advocates, researchers and healthcare providers.

Please feel free to reach out to your Pfizer Patient Affairs Liaison (PAL) who can also connect you with the Pfizer Medical team. Thank you, as always, for your partnership and for all that you do for the sickle cell community.

*Background: Pfizer withdrew Oxbryta from all markets globally and discontinued active voxelotor clinical trials in September 2024. This decision was based on the clinical trial and registry (real-world) data, which indicated that there were more vaso-occlusive crises (acute pain crises) and fatalities (deaths) for those taking Oxbryta. Since then, Pfizer has thoroughly reviewed the final Oxbryta data and shared it with regulators, including the U.S. Food and Drug Administration. The medicine remains off the market globally.