FDA grants Vanda Pharmaceuticals a rare formal evidentiary public hearing to review its refusal to approve HETLIOZ® for jet lag disorder, following a January 8 CRL and prior D.C. Circuit court ruling.
Written By: Pharmacally Medical News Desk
Vanda Pharmaceuticals Inc. scored a major regulatory milestone today when the U.S. Food and Drug Administration (FDA) agreed to hold a formal evidentiary public hearing on its proposal to deny the company’s supplemental new drug application (sNDA) for HETLIOZ® (tasimelteon) in jet lag disorder.
The FDA’s Office of the Commissioner confirmed the decision in a March 2, 2026, letter, paving the way for proceedings under 21 CFR Part 12.
This rare step potentially the first FDA drug approval hearing of its kind in over 40 years highlights the stakes in Vanda’s long battle. Historical records show such hearings are exceptionally uncommon, signaling deep legal and scientific disputes. The presiding officer will issue an initial decision under 21 CFR § 12.120 following the hearing.
“We are encouraged by the FDA’s decision,” said Mihael H. Polymeropoulos, M.D., Vanda’s President, CEO, and Chairman. “This procedural victory reflects our 7-year persistence for fairness and scientific truth on behalf of patients. It also marks a significant FDA reform toward greater transparency.”
Background: Court Victory Sets Stage
The hearing stems from Vanda’s August 2025 win in Vanda Pharmaceuticals Inc. v. FDA (case no. 24-1049) at the U.S. Court of Appeals for the D.C. Circuit. The court overturned the FDA’s initial refusal, ruling the agency unlawfully ignored Vanda’s statistically significant clinical trial data and dismissed expert evidence too quickly. It remanded the case, ordering the FDA to resolve the sNDA or initiate a hearing.
January 8 CRL: A Regulatory Setback Before the Hearing
Earlier in the year, on January 8, 2026, Vanda received a Complete Response Letter (CRL) from the FDA following an expedited re-review of the HETLIOZ® sNDA agreed under a collaborative framework in October 2025. In that letter, the agency acknowledged “positive efficacy” signals from controlled clinical trials but concluded that these data did not rise to the level of substantial evidence of effectiveness for jet lag disorder.
The FDA’s reasoning hinged largely on its view that the phase advance sleep models used in the trials (shifting bedtime by 5 or 8 hours) were not sufficiently analogous to real-world jet travel conditions, which involve factors like changes in oxygen pressure, noise, and lighting stimuli. Vanda has publicly disagreed with this interpretation, arguing that phase advance protocols are broadly accepted in circadian rhythm research and that its dataset met statutory standards for effectiveness.
HETLIOZ® (Tasimelteon)
HETLIOZ is a melatonin receptor agonist designed to regulate the body’s circadian rhythm.
The drug is currently approved in the United States for:
- Non-24-Hour Sleep-Wake Disorder
- Nighttime sleep disturbances associated with Smith-Magenis syndrome
The pending sNDA seeks to expand its label to include jet lag disorder, a circadian rhythm disruption that occurs when rapid travel across time zones misaligns the internal biological clock with local time.
Unmet Need in Jet Lag Disorder
Jet lag affects millions of travelers each year, including frequent business travelers, athletes, and military personnel deployed across time zones. Despite its widespread impact, there is currently no FDA-approved prescription therapy specifically indicated for jet lag disorder.
Vanda argues that tasimelteon’s mechanism of action directly addresses the underlying circadian misalignment that defines the condition. According to prior court records, the company submitted clinical trial data demonstrating statistically significant improvements, which became central to the legal dispute.
Reference
Vanda Announces FDA Grants Landmark Hearing for HETLIOZ® in Jet Lag Disorder, the First Drug Approval Hearing in Over 40 Years, 03 March 2026, Vanda Announces FDA Grants Landmark Hearing for HETLIOZ® in Jet Lag Disorder, the First Drug Approval Hearing in Over 40 Years
Vanda Therapeutics Receives Second FDA CRL for HETLIOZ in Jet Lag Disorder After Court-Mandated Re-Review, 08 January 2026, https://pharmacally.com/vanda-therapeutics-receives-second-fda-crl-for-hetlioz-in-jet-lag-disorder-after-court-mandated-re-review/