Supreme Court Denies Vanda’s Petition in Hetlioz Patent Case Against Teva

Supreme Court building_iStock, SeanPavonePhoto

Pictured: The U.S. Supreme Court building in Washington, DC/iStock, SeanPavonePhoto

The U.S. Supreme Court will not hear Vanda Pharmaceuticals’ petition in its patent case against Teva Pharmaceuticals regarding its sleep-wake disorder drug Hetlioz (tasimelteon), according to an order list published Monday.

Vanda CEO Mihael H. Polymeropoulos in a statement said that the company is “disappointed” by the Supreme Court’s decision to not hear the case, adding that the biotech is nevertheless “pleased” that the case “has drawn attention to an area of law that has broad and significant implications in life sciences innovation.”

Designed to be orally available, Hetlioz is a small molecule agonist of the melatonin MT1 and MT2 receptors, both of which are central to circadian rhythm control. The drug was approved in 2014 for the treatment of non-24-hour sleep-wake disorder.

Vanda filed its lawsuit in 2018 after Teva announced that it had submitted an Abbreviated New Drug Application to the FDA for a generic version of Hetlioz. At the time, Teva told Vanda that many of its patents covering Hetlioz are “invalid, unenforceable and/or will not be infringed.” However, Vanda alleged that Teva had infringed these patent protections.

In December 2022, a Delaware federal court not only rejected Vanda’s infringement claims but also found that four of its patents were invalid. The U.S. Court of Appeals for the Federal Circuit upheld this decision in 2023 and in October of the same year, Vanda announced that it intended to file a petition for a writ of certiorari.

“Vanda believes that the Federal Circuit’s approach improperly invalidates critical patent rights, which are necessary to ensure robust pharmaceutical research and development,” the biotech noted at the time. The company formally filed its petition in January 2024.

In its petition, Vanda argued that the Federal Circuit’s decision “threatens to render many advancements in drug development unpatentable,” according to Reuters. "That is an especially pernicious result for rare diseases, where patent-based incentives are crucial for innovators to invest the billions required to develop new, successful treatments."

Monday’s Supreme Court snub delivers another blow to Hetlioz, which last month suffered an FDA rejection. Vanda was proposing Hetlioz for the treatment of insomnia.

In addition to Hetlioz, Vanda also owns Fanapt (iloperidone), an atypical antipsychotic medication that won the FDA’s approval earlier this month for the treatment of manic or mixed episodes in bipolar I disorder. Fanapt is also indicated for schizophrenia, for which the drug was approved in 2009.

Tristan Manalac is an independent science writer based in Metro Manila, Philippines. Reach out to him on LinkedIn or email him at or

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