An official from the U.S. Food and Drug Administration (FDA) defended the agency's request for a new placebo-controlled study for uniQure N.V.’s (NASDAQ:QURE) experimental gene therapy for Huntington's disease.

The FDA official noted that the company's existing trial design failed to sufficiently prove the treatment slowed disease progression.

FDA’s Stand On UniQure’s Gene Therapy

On Monday, the FDA advised against using Phase 1/2 study data as primary evidence for the marketing application of AMT-130, uniQure’s investigational gene therapy for Huntington's disease.

The FDA strongly recommended that uniQure conduct a prospective, randomized, double-blind, sham surgery-controlled study to proceed.

uniQure plans to request a Type B meeting in the second quarter of 2026 for further discussions.

The FDA official told Reuters that the agency has historically required randomized, placebo-controlled trials when evaluating potential therapies for Huntington's disease.

According to the official, comparisons against external patient datasets — such as those used by uniQure — are not considered adequate evidence of clinical benefit.

Debate Over Evidence From uniQure’s Prior Study

UniQure previously reported that its study results showed a statistically significant slowing of disease progression over three years using a clinical rating scale.

The comparison was made against external datasets of Huntington's patients rather than against a randomized placebo group.

Citing the FDA official, Reuters noted that this type of comparison was not acceptable for determining whether the therapy truly slowed disease progression.

In late 2024, uniQure had said it reached an agreement with the FDA on key components for an accelerated approval application. However, the official clarified that the agency never indicated the company's existing study would be sufficient for approval.

Dispute Over Procedure Description

During a conference call discussing financial results, Walid Abi-Saab, uniQure's chief medical officer, described the FDA as asking the company to "superficially drill a hole on the skull" as part of a placebo procedure.

The FDA official disputed that characterization. Instead, the agency suggested a randomized trial that could use a sham procedure involving a small scalp incision, according to the official.

On Wednesday, Andrew Nixon, a spokesperson for the Department of Health and Human Services, also criticized uniQure's description of the FDA request on social media, calling the claim false.

QURE Price Action: uniQure shares were up 18.81% at $10.74 at the time of publication on Thursday. The stock is near its 52-week low of $7.76, according to Benzinga Pro data.

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