The Food and Drug Administration requires companies that make specialized cancer therapies, known as CAR-Ts, to add a boxed warning that the treatments themselves can cause cancer.
The agency noted that the benefits still outweighed the risks of the therapy, which involves eliminating a type of white blood cell — T cells — then genetically modifying them to create proteins called chimeric antigen receptors (CARs). Reinfused into a patient’s blood, the modified cells allow T cells to attach to and kill cancer cells.
But the therapies, which mainly treat blood cancers including multiple myeloma, had already warned of dangerous immune responses and neurological risks. And the new warning follows reports of about 25 cases of secondary cancers that federal health officials and others suspect are caused by CAR-T treatments, although further investigations may be necessary to establish a definitive link. The therapy has been used by at least 27,000 people patients since it was first approved by the FDA in 2017, the agency said.
Cancer patients who receive CAR-T treatments tend to have few options and are unlikely to change course even with the new warning, said Dr. John DiPersio, an oncologist at the University of Washington to St. Louis.
“The risk of not following this treatment for most patients who benefit from it is rapid progression of their disease or certain death,” he said.
The FDA raised concerns about side effects from the treatments late last year.
In letters dated Jan. 19, the agency outlined warnings expected to be included by some of the companies making CAR-T therapies, which had also been ordered to monitor patients for secondary cancers and report them to the FDA. Secondary cancers can lead to hospitalizations. or death, the agency noted, requiring pharmaceutical companies to provide warnings on drug labels that secondary cancers “may manifest as early as weeks after infusion and can lead to life-threatening consequences.”
The FDA sent letters to these companies: Bristol-Myers Squibb, Abecma manufacturer; Juno Therapeuticto Bristol-Myers Squibb Company, manufacturer of Breyanzi; Janssen Biotechnology from Johnson & Johnson, manufacturer of Carvykti; Novartis, of Kymriah; And Pharma kiteof Yescarta.
Given the poor prognosis for patients considering CAR-T therapies, Dr. DiPersio said, the new warning amounts to “much ado about nothing.” He said he hoped the news would not dampen additional investment or the study of treatments for other serious medical problems. Some drugmakers are studying the use of CAR-T therapy to treat lupus, an autoimmune disease.
“We cannot create an environment so frightening that companies and investigators avoid this approach because it is considered too dangerous – because it is not,” he said.
Financial analysts also predict little fallout, Brian Abrahams, an analyst at RBC Capital Markets, said in an email.
“It’s still a very rare side effect,” he said. “These are sick patients who are receiving these therapies, and most CAR-T treatments have shown very clear benefits, including prolonged survival. So we do not expect these label changes to materially reduce use of these agents.”