Pfizer is disappointed again due to critical tests of sickle cell disease drug failure
A Pfizer drug designed to address serious problems associated with sickle cell disease failed to beat placebo in a Phase 3 clinical trial. This is Pfizer’s latest setback in this hereditary blood disease, and for safety reasons, the drug giant has withdrawn another medical science from the market.
Sickle cell disease causes hemoglobin to have a rigid crescent shape. These malformed cells block capillaries and small blood vessels, a painful complication called the crisis of vascular familiarity. Pfizer's drug contains proteinomab, which is designed to improve this complication.
Protein-containing monoclonal antibody is an antibody designed for use in bulk proteins called block P-selectin. This protein was found on the surface of activated platelets, promoting adhesion of these cells to the inner wall of blood vessels. While this is important in response to blood clotting that is damaged, it also promotes the crisis of vascular familiarity in sickle cell disease. By blocking P-selectin, hope to reduce the crisis of vascular familiarity.
Pfizer is evaluating a study that recruited 241 patients aged 16 and older with a proven diagnosis of sickle cell disease, experiencing a crisis of 2 to 10 vascular familiarity the year before. A single dose of glycoprotein-containing monoclonal antibody was intravenously injected every 12 weeks. The main goal of the trial was to measure the crisis of vascular familiarity during the 48-week treatment period.
Pfizer said Friday that no specific numbers were available compared to placebo, and the candy content did not achieve a statistically significant reduction. The company said the drug is well tolerated. The most common side effects include anemia, joint pain, back pain, and headache. Michael Vincent, Pfizer’s chief inflammation and immunology officer, described the outcome of the trial (thrive-131) as a disappointment with the sickle cell community and the company.
“While Thrive-131 results do not meet our expectations, we remain committed to better understanding these results and share them with the medical and sickle cell communities to promote our collective understanding of sickle cell disease,” Vincent said in a prepared statement. “We remain focused on bringing much-needed treatments to patients with sickle cell disease.”
Candy Contains was originally developed by Roche. Global hematologic therapy was licensed to the molecule in 2018, thus advancing it to medium-term clinical development. In 2022, Pfizer reached a $5.4 billion deal to acquire global blood. At the heart of the deal is another sickle cell disease drug, Oxbryta, which won FDA approval in 2019. Oxbryta is a small molecule designed to block the process by which hemoglobin polymerization and red blood cells become sickle-like.
Last September, Pfizer voluntarily withdrew the bryworm from the market after post-sale clinical tests, showing a higher incidence of cowboy population crisis and higher deaths in the cowboy population and placebo sectors. In practical studies of this drug, a higher incidence of vascular familiarity crisis was also observed. In an announcement Friday that included bags, Pfizer said it had completed its Oxbryta data evaluation review and shared it with the FDA and the European Medicines Agency. The company promises to release a comprehensive analysis that includes other denim graph data and analyze this year.
Pfizer's pipeline of drugs for sickle cell disease includes another asset in the global blood. Osivelotor is the next generation version of Oxbryta. Although the drug has reached its Phase 3 testing, enrollment remains suspended due to some clinical retention issued by the FDA last year. Pfizer said it will provide the latest information about the study as they become available.
Image: Meletios Verras, Getty Images
