FDA Setbacks for UniQure and REGENXBIO, Sarepta CEO Steps Down

Regulatory experts question FDA decision-making as gene therapy companies face delays and rejections

Published on Mar. 4, 2026

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The FDA has delivered setbacks to UniQure and REGENXBIO for their respective gene therapy candidates, requiring UniQure to conduct additional clinical trials and rejecting REGENXBIO's therapy for Hunter syndrome. Meanwhile, Sarepta Therapeutics CEO Doug Ingram has stepped down, and the company projects flat or declining sales for its Duchenne muscular dystrophy gene therapy. Regulatory experts have expressed concerns about the FDA's decision-making processes, with reports of a toxic workplace environment within the Center for Biologics Evaluation and Research (CBER).

Why it matters

These developments highlight the ongoing challenges faced by gene therapy companies in navigating the regulatory landscape, as the FDA's decisions and internal dynamics come under increased scrutiny. The outcomes for UniQure, REGENXBIO, and Sarepta could have significant implications for patient access to these potentially transformative therapies.

The details

UniQure revealed that the FDA will require the company to conduct a randomized, double-blind, sham surgery–controlled Phase 3 study for its Huntington's disease gene therapy candidate. REGENXBIO received a complete response letter from the FDA for its Hunter syndrome gene therapy, with the rejection driven by issues with the study's population, controls, and use of surrogate markers. Regulatory experts have expressed concerns that the FDA's decision-making process is becoming increasingly opaque, with the agency reportedly initiating a probe into complaints of a toxic workplace environment within CBER, led by director Vinay Prasad. Additionally, Sarepta Therapeutics CEO Doug Ingram stepped down, and the company projected flat or declining sales for its Duchenne muscular dystrophy gene therapy, Elevidys.

  • On March 4, 2026, the FDA published a complete response letter rejecting REGENXBIO's gene therapy for Hunter syndrome.
  • In early 2026, the FDA informed UniQure that it will require the company to conduct an additional randomized, double-blind, sham surgery–controlled Phase 3 study for its Huntington's disease gene therapy candidate.
  • Last week, Sarepta Therapeutics CEO Doug Ingram stepped down from his position.

The players

UniQure

A biopharmaceutical company focused on developing gene therapies, including a candidate for Huntington's disease.

REGENXBIO

A clinical-stage biotechnology company developing gene therapies, including a candidate for Hunter syndrome.

Sarepta Therapeutics

A biopharmaceutical company focused on developing gene therapies for rare neuromuscular diseases, including Duchenne muscular dystrophy.

Vinay Prasad

The director of the Center for Biologics Evaluation and Research (CBER) at the FDA, who is at the center of concerns about the agency's decision-making processes and workplace environment.

Doug Ingram

The former CEO of Sarepta Therapeutics, who stepped down to spend more time with his family.

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What they’re saying

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— Gordon Edgar, Grocery employee (Instagram)

What’s next

The judge in the case will decide on Tuesday whether or not to allow Walker Reed Quinn out on bail.

The takeaway

These setbacks for gene therapy companies highlight the ongoing challenges in navigating the regulatory landscape, as the FDA's decision-making processes come under increased scrutiny. The outcomes could have significant implications for patient access to these potentially transformative therapies.