- The Food and Drug Administration on Monday granted accelerated approval to Pfizer’s Elrexfio for people with advanced multiple myeloma, making it the third drug of its type to treat the blood cancer.
- Known generically as elranatamab, Elrexfio is for people who got sicker after at least four rounds of prior treatment. Results from clinical testing, which need to be confirmed with further study, showed 58% of study particiapnts responded to treatment.
- The approval is similar to clearances granted by the FDA to Johnson & Johnson’s drugs Tecvayli and Talvey, the latter of which received an OK last week. Pfizer, which set Elrexfio’s price at about $41,500 per month, aims to compete with more convenient dosing.
As with other types of cancers, researchers have sought ways to turn the immune system against multiple myeloma. Their efforts have borne fruit with engineered T cell therapies like Bristol Myers Squibb and 2Seventy Bio’s Abecma and J&J and Legend Biotech’s Carvykti.
Those so-called CAR-T drugs are made from patients’ own T cells and require a complex manufacturing process, although for some patients treatment can deliver lasting benefits with a single infusion.
Elrexfio, Tecvayli and Talvey are off-the-shelf drugs called “bispecific” antibodies, binding to proteins on both diseased cells and T cells to trigger an immune response. They are given for as long as patients can tolerate and their disease remains in check.
While Elrexfio and Tecvayli both target a protein called BCMA that’s found on malignant plasma cells, Talvey is aimed at another one known as GPRC5D.
All of these newer multiple myeloma drugs have immune-related side effects that can require hospitalization or stays nearby for monitoring. In the case of Elrexfio, the FDA is mandating a 48-hour hospital stay after the first dose and 24 hours after the second dose in a “step-up” schedule. Under their approvals, patients taking Tecvayli and Talvey must stay 48 hours in the hospital after each of their step-up doses.
Elrexfio has a single fixed dose, while Tecvayli and Talvey’s dose is dependent on patients’ weight. Once the step-up period is completed, patients receive an Elrexfio shot every other week, compared with the weekly shots of the J&J drugs.
Pfizer emphasized the dosing advantage in announcing Elrexfio’s approval. However, J&J remains a strong competitior with a multiple myeloma franchise that includes its CAR-T drug, the two bispecific therapies and Darzalex, an antibody drug used in earlier stage disease.
FDA granted an accelerated approval based on treatment response data. Elrexfio is in two Phase 3 trials that will compare its use against active treatments in earlier-stage disease and in patients who have completed bone marrow transplants. Success in those studies could be used to convert the accelerated clearance to full.
At a $41,500 average monthly list price, a typical treatment course of Elrexfio will cost about $330,000 based on the duration of therapy reported during clinical testing, Pfizer said in an emailed statement.
The company expects bispecifics like Elrexfio to become standard treatment for multiple myeloma, and executives have forecast the potential for annual revenue to climb as high as $4 billion.