Dive Brief:
- Labcorp received Food and Drug Administration approval for a companion diagnostic that determines if a patient is eligible for a gene therapy, the company said Monday.
- The FDA approved the hemophilia B gene therapy, Pfizer’s Beqvez, Friday and made testing for neutralizing antibodies against the viral delivery vector a condition of the authorization.
- Labcorp’s test detects pre-existing neutralizing antibodies that could affect patient safety or the efficacy of the treatment.
Dive Insight:
Beqvez consists of an adeno-associated virus (AAV) vector that delivers a functional copy of a gene that is faulty in people with hemophilia B. Some people may have been exposed to a similar virus and now have immunity to the AAV capsid used to deliver Pfizer’s treatment.
Because pre-existing immunity can limit the efficacy of the gene therapy, the FDA has restricted the use of Beqvez to patients who do not have neutralizing antibodies against the vector. Testing for pre-existing neutralizing antibodies is the first step in the FDA instructions for giving the gene therapy.
Healthcare providers who are considering prescribing Beqvez can enroll in a testing program provided by Labcorp. The clinical laboratory is providing its nAbCyte assay to eligible patients at no cost through its testing access agreement with Pfizer.
Beqvez is approved in adults with moderate to severe hemophilia B who currently use drugs to prevent bleeds or have repeated, spontaneous bleeding. Analysts surveyed by Bloomberg expect Beqvez to make around $400 million in annual sales by 2030. Beqvez has a list price of $3.5 million, the same fee that CSL Behring and uniQure set for their rival hemophilia B gene therapy Hemgenix.
The FDA approved Hemgenix in 2022 without requiring the use of a companion diagnostic. Hemgenix uses an AAV5 vector that researchers showed to be effective in most patients regardless of whether they have pre-existing neutralizing antibodies. While Hemgenix is free from the label restriction, sales of the gene therapy have fallen short of expectations so far.
Beqvez is under review at the European Medicines Agency. Labcorp CEO Adam Schechter identified internataional expansion of the companion diagnostic business as one of three longer-term opportunities at the J.P. Morgan Healthcare Conference in San Francisco in January.
“As we develop these specialized tests and we work side by side with our pharma colleagues to develop those, if there's companion diagnostics that need to be with a product that they launch, we want to be able to bring that companion diagnostic to markets around the world,” Schechter said.
