Guy Young, MD

Young shared with his real-world experiences with etranacogene dezaparvovec gene therapy.

A Positive Outlook on Gene Therapy for Hemophilia B Post-Discontinuation, with Guy Young, MD

Pfizer recently announced that it was discontinuing development and commercialization of fidanacogene elaparvovec an adeno-associated virus (AAV) vector-based gene therapy for the treatment of hemophilia B.

The therapy was approved only 1 year ago, in April 2024, under the name Beqvez.

Upon approval, fidanacogene elaparvovec joined pioneer gene therapy etranacogene dezaparvovec-drlb, approved by the FDA under the name Hemgenix for the same indication in 2022.

HCPLive spoke with Guy Young, MD, Director, Hemostasis and Thrombosis Program, Children’s Hospital of Los Angeles, and Professor of Pediatrics, Keck School of Medicine of University of Southern California, who served as an investigator on the etranacogene dezaparvovec program and who has administered it in the commercial setting, to learn more about his outlook on gene therapy in the hemophilia B field amidst the discontinuation.

Young stressed that his outlook on gene therapy in the field remained positive. He shared his experiences with etranacogene dezaparvovec in the real world and the patient and clinician reception.

“I think that the field is ready. We're seeing more and more patients receiving this,” Young said. “I think with gene therapy, there was all this excitement, and then it… kind of died off. But I think we're at that point where, where the tide is going to turn… the future products will be either different or better, or offer things that Hemgenix cannot offer… I think that hemophilia patients are excited about and are ready for products that can provide them the potential for getting cured.”

Young’s relevant disclosures included Genentech/Roche, Grifols, and Takeda, BioMarin, Novo Nordisk, Sanofi, Spark, Takeda, and UniQure.

Santhosh C. Pfizer stops commercialization of hemophilia gene therapy Beqvez. Reuters. February 21, 2025. Accessed April 25, 2025. 

https://www.reuters.com/business/healthcare-pharmaceuticals/pfizer-says-it-will-end-global-development-gene-therapy-beqvez-nikkei-reports-2025-02-20/

U.S. FDA Approves Pfizer’s BEQVEZ™ (fidanacogene elaparvovec-dzkt), a One-Time Gene Therapy for Adults with Hemophilia B. News release. Pfizer. April 26, 2024. Accessed April 25, 2025. https://www.businesswire.com/news/home/20240425269649/en/U.S.-FDA-Approves-Pfizer%E2%80%99s-BEQVEZ%E2%84%A2-fidanacogene-elaparvovec-dzkt-a-One-Time-Gene-Therapy-for-Adults-with-Hemophilia-B

Johnson V. FDA approves first gene therapy for hemophilia B. HCP Live. November 23, 2022. Accessed April 25, 2025. https://www.hcplive.com/view/fda-approves-first-gene-therapy-hemophilia-b.

Guy Young, MD

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