Pfizer stock closed roughly flat Thursday after the pharma titan voluntarily pulled its sickle cell drug, Oxbryta, from the market following patient deaths.
The company spent $5.4 billion in 2022 to buy Oxbryta maker Global Blood Therapeutics. The drug is a small sales contributor for Pfizer — analysts estimate just $395 million in 2024 sales — but it's one of the few approved treatments for the blood disease.
Investors are likely questioning the future of GBT's assets, Leerink Partners analyst David Risinger said in a report. Pfizer is still developing GBT-601, a next-generation sickle cell disease treatment. Similar side effects, including one patient death, have occurred in studies of GBT-601.
Meanwhile, the news proved a boon for companies working on sickle cell drugs.
Pfizer stock initially fell and then rose a small fraction to 28.97. On the other hand, Agios Pharmaceuticals stock reversed earlier gains and closed down 2% at 48.05. Crispr Therapeutics, which make a gene-editing treatment for sickle cell disease, saw shares edge up 1.2% to 46.49. Beam Therapeutics shares advanced 2.5% to 25.12.
Penny stocks Editas Medicine, Fulcrum Therapeutics and Bluebird Bio also moved higher.
Pfizer Stock: Other GBT Drugs?
Sickle cell disease is characterized by painful events known as vaso-occlusive crises. In its news release announcing Oxbryta's demise, Pfizer said there was an imbalance of vaso-occlusive crises and deaths among Oxbryta patients. The data suggest Oxbryta's risks now outweigh its benefits.
In addition to pulling Oxbryta from the market, Pfizer said it stop all Oxbryta studied worldwide.
The news came as a shock to Pfizer stock investors following the costly takeover of GBT. Pfizer had estimated Oxbryta and GBT-601 could generate a collective $3 billion in worldwide peak sales.
"Although the financial impact of Oxbryta termination is modest, investors may also question GBT-601 prospects," Leerink's Risinger said. "We await further clarity from Pfizer on whether GBT-601 will be impacted."
Already, Pfizer has pushed back the primary completion date of a study of GBT-601 by two years to 2028.
Agios, Fulcrum Could Benefit Most
Fellow Leerink analyst Mani Foroohar expects the Pfizer stock news to have little impact to genetic medicines space working on treatments for sickle cell disease.
That includes Crispr and partner Vertex Pharmaceuticals, which sell an approved gene-editing drug, Casgevy. Bluebird Bio also makes an approved gene therapy called Lyfgenia. Beam and Editas are also testing gene-editing approaches to SCD.
"Specifically, Oxbryta use skews to milder patients or those unwilling to undergo/ineligible for hematopoietic stem cell transplantation," he said in a report.
But Fulcrum could benefit, says Leerink's Marc Schwartz. Fulcrum is working on a treatment for the blood disease, but has struggled to enroll its Phase 1 study. This gets the company one step closer to fulfilling its plan to have the results of that study in 2025.
Further, Agios could benefit, says Piper Sandler analyst Christopher Raymond. Agios is working on a treatment called mitapivat. Agios expects to have Phase 3 data in 2025.
Since mitapivat targets a similar patient population as Oxbryta, if mitapivat continues to show benefit on pain crises (which Oxbryta was not able to demonstrate), we anticipate this will enable an easier regulator review, especially now considering the greater demands from patients who can no longer access Oxbryta," he said in a client note.
Raymond has an overweight rating on Agios stock, but doesn't list a rating for Pfizer stock.
Follow Allison Gatlin on X, the platform formerly known as Twitter, at @IBD_AGatlin.
