Oxbryta Lawsuit Filed Over Vaso-Occlusive Crisis (VOC) from Recalled Sickle Cell Disease Drug

The Pfizer subsidiary Global Blood Therapeutics faces a product liability lawsuit over its recalled sickle cell anemia drug Oxbryta, indicating that the medication caused an Illinois man to suffer a stroke after it failed to decrease the number of painful vaso-occlusive crises (VOCs) related to the blood disease.

Oxbryta (voxelotor) is an expensive prescription drug approved for the treatment of sickle cell disease, which is a lifelong blood disorder that affects protein in the blood, causing blood cells to break down and die due to a lack of oxygen. It is a serious condition, which can cause blood flow blockage, infections, pain and fatigue.

Global Blood Therapeutics introduced Oxbryta in 2019, after it was granted accelerated approval by the U.S. Food and Drug Administration (FDA), as the first drug to treat the root cause of sickle cell disease, by improving hemoglobin levels in the body and helping the blood cells retain more oxygen.

Pfizer acquired Global Blood Therapeutics for $5.4 billion in 2022, and continued to sell Oxbryta at an estimated annual cost of more than $88,000 for each patient. However, following an alarming number of reports involving users experiencing painful sickle cell complications and deaths, Pfizer announced a global Oxbryta recall late last month, after determining that risks associated with the treatment outweigh the potential benefits.

Late last week, Illinois resident Trebor Hardiman became the first of what is expected to be a number of former patients to bring an Oxbryta lawsuit, alleging that Global Blood Therapeutics knew or should have known about the drug’s detrimental side effects, but failed to warn users or the medical community.

The complaint (PDF) was filed in the California Superior Court for San Francisco on October 23, indicating that Hardiman was diagnosed with sickle cell anemia when he was a child and began taking Oxbryta in 2020. However, while on the drug, the lawsuit indicates he experienced more VOCs than before the treatment began, which resulted in the need for blood transfusions, severe pain and swelling.

Vaso-occlusive events occur when the red blood cells block blood flow, and the tissues become deprived of oxygen. This can cause an inflammatory response, which can lead to symptoms like pain in the chest, back and limbs, as well as fever. Patients often have to be hospitalized and can suffer kidney failure and stroke. Additionally, many patients can suffer death following a vaso-occlusive event.

The lawsuit indicates Hardiman suffered a stroke in recent weeks due to Oxbryta side effects, resulting in vision loss and the loss of his ability to drive and conduct many normal everyday activities. He was informed of the recall on September 25, and stopped using the medication.

According to Hardiman, until that call, he had never been informed that Oxbryta was linked to a higher rate of VOC, and that there had been a higher rate of death in Oxbryta treatment groups than patients given a placebo. However, there were also health risks in ending the treatment as well.

“In the short time since stopping the medication, Plaintiff has suffered multiple VOCs and has been hospitalized for approximately a week,” the lawsuit states. “As of the filing of this lawsuit, Plaintiff is still hospitalized with complications from stopping the medication.”

In July, European drug regulators warned that out of a clinical trial involving only 236 subjects, there were eight deaths reported among Oxbryta users, compared to two among patients given a placebo, the lawsuit reports. The study subjects were children between the ages of 2 and 15 years old.

Pfizer indicates the problems with Oxbryta require more research before they can understand what is causing the increased risks. But Hardiman’s lawsuit indicates that it is clear Oxbryta’s manufacturers failed to do adequate testing on the drug before making it available to the public. Had they done so, they would have known the drug did not work as intended.

He presents claims of strict liability, design defect, failure to warn, negligence, breach of warranty, unjust enrichment, false and misleading advertising, and violation of California civil codes.