The U.S. Food and Drug Administration (FDA) has agreed to hold an official public hearing regarding the expansion of the indication for Hetlioz (tasimelteon), a drug developed by Vanda Pharmaceuticals. This decision marks an unexpected turn in the pharmaceutical company’s seven-year battle to gain approval for the drug to treat jet lag disorder. The company stated that such hearings have not been held in the U.S. for over 40 years.
Vanda Pharmaceuticals had been seeking approval for this indication since 2019, when the FDA first rejected the application. In 2022, the company filed a lawsuit against the regulator.
In January 2026, the FDA rejected Vanda Pharmaceuticals for a second time. The regulator considered that the clinical trial protocols did not accurately reflect the conditions of real air travel and the subsequent jet lag. The company disagreed with this decision and continued to seek a review.
Two legal victories by Vanda played a key role in the current decision. In 2024, a District of Columbia court ordered the FDA to either review the application or hold a hearing. At that time, the documents had been with the agency for nearly 2,000 days, and the company’s request for a hearing for over 500 days. However, the regulator ignored this requirement and issued an official refusal instead of holding hearings.
In 2025, a federal appeals court overturned this decision and remanded the case to the FDA. The company expected that this would be followed by either approval or the scheduling of hearings. As a result, the regulator chose the latter path.
The CEO of Vanda Pharmaceuticals, Mihael Polymeropoulos, called the FDA’s decision a “procedural victory” that reflects the company’s seven-year persistence in advocating for scientific truth and patient interests. The company had previously criticized the regulator on multiple occasions, pointing to “serious flaws in FDA regulations governing drug-approval processes” and filing lawsuits on other matters related to Hetlioz.
The FDA has not yet officially commented on the decision to hold the hearings.
Hetlioz was first approved by the FDA in 2014 for the treatment of a rare sleep-wake disorder that disrupts the 24-hour cycle (non-24-hour sleep-wake disorder). In 2020, the indication was expanded to include Smith-Magenis syndrome.
