Hemophilia B gene therapy Beqvez offers new choice: Pfizer official
Treatment expected to be available this quarter, U.S. executive says
Pfizer is preparing to launch its hemophilia B gene therapy Beqvez (fidanacogene elaparvovec-dzkt) after securing a U.S. approval for the treatment last month.
Beqvez is the second gene therapy to be approved for adults with moderate to severe hemophilia B in the U.S., following the clearance of Hemgenix in 2022.
“With the U.S. approval of BEQVEZ, physicians and patients now have another choice in the treatment of hemophilia B,” Sonal Bhatia, MD, senior vice president and head of U.S. specialty care medical affairs at Pfizer, said in a written Q&A with Hemophilia News Today.
Beqvez is also cleared in Canada and is under review in the European Union.
Bhatia said gene therapies, which directly address the disease’s underlying cause, offer “transformative potential” for long-term bleed control in eligible patients, who are often susceptible to breakthrough bleeds despite being on standard of care preventive therapies.
“There is a clear interest and anticipation from the physician and patient community for gene therapy and its potential use alongside conventional treatments,” Bhatia said.
Therapy to be available this quarter
Pfizer is focusing on Beqvez’s rollout. The therapy is expected to become available by prescription to eligible patients this quarter, Bhatia said.
The company is “proactively working with treatment centers, payers, and the hemophilia community to help ensure the healthcare system is appropriately prepared to deliver Beqvez to the patients who can benefit from it,” she said.
That includes offering personalized patient support services through Pfizer’s GeneTogether program. Through the program, patients can access educational materials about what happens before, during, and after receiving gene therapy, and can find help understanding insurance coverage and financial options.
Gene therapies are among the most expensive treatments in the world. Beqvez has a list price of $3.5 million, the same as Hemgenix.
To help ensure that insurance companies are willing to cover the cost, Pfizer is offering a warranty program based on the “durability of a patient’s response,” Bhatia said. The program provides “financial protection by insuring against the risk of efficacy failure,” with the aim of making it easier for patients to access treatment, she said.
Pfizer also offers a co-pay assistance program to help manage out-of-pocket costs for patients who are commercially insured.
Factor replacement therapy has long been the standard prophylactic treatment for hemophilia B. It involves regularly administering infusions into the bloodstream of a working version of factor IX (FIX), the blood clotting protein patients that’s faulty or missing due to mutations in the F9 gene that encodes its production.
But despite these treatments, “many people living with moderate to severe hemophilia B are at risk of spontaneous bleeding episodes, which can result in painful joint damage and mobility issues,” Bhatia said.
This can significantly affect a person’s daily life. Bhatia pointed to studies showing that nearly 40% of severe hemophilia patients who are employed experience disease-related restrictions in job performance, and that at least 13% have faced unemployment because of it.
Providing people with ‘more time for the things they love’
With Beqvez, the hope is to “allow people living with hemophilia more time for the things they love and support their ability to engage in the workforce, school, and society,” Bhatia said.
The gene therapy, intended as a one-time treatment, provides patients’ liver cells with a healthy copy of F9. The therapy provides the body with the tools to continuously produce its own FIX protein in the long term, offering lasting bleed prevention.
The potential benefits of Beqvez were demonstrated in the open-label Phase 3 BENEGENE-2 clinical trial (NCT03861273), which tested the effects of the gene therapy in men, ages 18-65, with moderate to severe hemophilia B.
Bleeds were eliminated in 60% of patients after they received Beqvez for up to three years, while only 29% of patients experienced complete bleed control while on standard prophylaxis during a lead-in period prior to receiving the gene therapy.
The overall median annualized bleeding rate was zero after treatment with Beqvez, compared with 1.3 bleeds per year during the lead-in period. The mean annualized bleeding rate dropped from 4.5 bleeds per year while patients were on prophylaxis to 2.5 bleeds per year after receiving Beqvez.
An ultimate goal of gene therapy would be for patients to be less reliant on replacement therapy, or to eliminate it altogether, avoiding “years of medical burden,” Bhatia said.
Still, the long-term effects of Beqvez, and whether it will offer sustained bleed control for many years, will only be known once treated patients have been followed for a longer period of time.
BENEGENE-2 participants are being followed for up to 15 years: six years in the current study and nine more in a long-term Phase 3 extension study (NCT05568719).
Long-term outlook ‘encouraging’
Bhatia said Pfizer is “optimistic” about the gene therapy’s long-term safety and efficacy profile.
Patients from an earlier Phase 1/2a trial (NCT02484092) and long-term extension study (NCT03307980) have been followed for up to six years, during which time FIX activity has remained stable, according to Bhatia. With FIX activity generally in the mild hemophilia to normal range, patients have also maintained low bleed rates during that time.
While more long-term data are collected, the company is conducting exploratory modeling analyses aiming to predict the treatment’s long-term effects based on available clinical trial data.
Results from those analyses presented earlier this year indicated that a one-time infusion was predicted to be efficacious for more than 20 years, maintaining FIX at levels not achievable with recommended replacement therapy dosing. Bhatia said Pfizer will continue to update the modeling analyses as more data become available, adding that the current results are “encouraging.”
Bhatia touted the recent Beqvez approval as “a testament to Pfizer’s continued effort to advance the standard of care for people living with hemophilia.”
The company, which markets a number of approved hemophilia treatments, has other experimental ones in the pipeline. Those include giroctocogene fitelparvovec, a gene therapy for hemophilia A that’s in Phase 3 testing, and marstacimab, an injectable therapy currently under review in the U.S. and Europe for hemophilia A and B patients without inhibitors.
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