The patent dispute between Vanda Pharmaceuticals and Apotex over the sleep disorder drug Hetlioz® (tasimelteon) culminated in a decisive victory for Apotex, with courts invalidating Vanda’s patents for obviousness. Here’s a breakdown of the litigation and its implications:
Case Overview
- Parties: Vanda Pharmaceuticals (plaintiff) vs. Apotex Inc. and Apotex Corp. (defendants).
- Drug: Hetlioz® (tasimelteon), used to treat Non-24-Hour Sleep-Wake Disorder (Non-24).
- Patents Challenged: Four Orange Book-listed patents (RE604, ’829, ’910, ’487) covering dosing regimens and methods of treatment with tasimelteon[1][4][13].
- Legal Basis: Apotex’s filing of an abbreviated new drug application (ANDA) with Paragraph IV certifications alleging non-infringement and invalidity of Vanda’s patents[10][12].
Key Litigation Events
-
District Court Ruling (2023)
The U.S. District Court for Delaware invalidated all four asserted patents as obvious under 35 U.S.C. § 103. The court found:
- Prior art (e.g., studies on melatonin agonists) provided a clear basis for using tasimelteon to treat Non-24[3][16].
- Combining known elements (e.g., 20mg dosing, circadian rhythm entrainment) would have been predictable to a person of ordinary skill in the art[15].
- Secondary considerations (e.g., commercial success) did not overcome the obviousness determination[4][16].
-
Federal Circuit Affirmance (May 2023)
The appellate court upheld the invalidity ruling, emphasizing that Vanda’s patents merely applied existing knowledge about tasimelteon’s mechanism of action. The court rejected arguments about “unexpected results” and deferred to the district court’s factual findings[3][14].
-
Supreme Court Denial (April 2024)
The U.S. Supreme Court declined to review the case, leaving the Federal Circuit’s decision intact. Vanda had argued the lower courts misapplied the “reasonable expectation of success” standard for obviousness, but the justices provided no commentary[1][15].
Legal and Market Impact
- Generic Competition: Apotex and Teva (a co-defendant in related litigation) now market generic tasimelteon, reducing Hetlioz®’s $285,000/year list price[15].
- Precedent on Obviousness: The courts reinforced that combining known elements—even for new disorders—may render patents invalid if the combination is predictable[3][15].
- Strategic Use of ANDA Challenges: The case underscores how generic manufacturers leverage Paragraph IV certifications to expedite market entry[12][13].
Analysis of Key Issues
1. Obviousness of Dosing Patents
The courts found Vanda’s dosing claims (e.g., 20mg nightly) lacked inventiveness because prior animal and clinical studies had already established tasimelteon’s pharmacokinetics and safety profile. This aligns with precedents like KSR Int’l Co. v. Teleflex Inc., which discourage patenting routine experimentation[3][16].
2. Secondary Considerations
Vanda argued long-felt need and commercial success, but the district court dismissed these factors. Notably, reexamination proceedings had acknowledged some evidence of long-felt need, but the court deemed this insufficient to override obviousness[4][16].
3. FDA and Litigation Strategy
Vanda’s subsequent lawsuits against the FDA—to block generic approvals—highlight the company’s aggressive tactics to preserve market exclusivity. However, courts have consistently sided with generic manufacturers in this case[15].
Conclusion
The Vanda-Apotex litigation exemplifies the high stakes of Hatch-Waxman patent battles. By invalidating dosing and method-of-treatment patents as obvious, the courts prioritized generic competition over incremental innovations. For pharmaceutical companies, this ruling underscores the need for robust non-obviousness evidence, particularly when repurposing known compounds for new disorders.
References
- https://www.cozen.com/news-resources/news/2024/supreme-court-won-t-review-vanda-s-ip-obviousness-appeal
- https://www.supremecourt.gov/DocketPDF/23/23-768/295665/20240112152259752_Vanda.cert.appendix.pdf
- https://www.ipiqblog.com/wp-content/uploads/sites/47/2024/05/23-1247.OPINION.5-10-2023_2124577-Vanda-v.-Teva-2.pdf
- https://casetext.com/case/vanda-pharm-v-teva-pharm-us-2
- https://patentlyo.com/media/2023/07/Vanda-EnBanc-Brief.pdf
- https://ecf.cofc.uscourts.gov/cgi-bin/show_public_doc?2023cv0629-62-0
- https://fedcircuitblog.com/wp-content/uploads/2023/06/Vanda-Petition-1.pdf
- https://www.ded.uscourts.gov/sites/ded/files/opinions/18-651.pdf
- https://fedcircuitblog.com/wp-content/uploads/2023/06/Vanda-Petition-1.pdf
- https://dockets.justia.com/docket/delaware/dedce/1:2020cv00083/71208
- https://insight.rpxcorp.com/litigation_documents/13632065
- https://dockets.justia.com/docket/delaware/dedce/1:2019cv02375/71064
- https://www.sternekessler.com/news-insights/news/fed-circ-wont-bar-generic-sleep-meds-amid-vanda-appeal/
- https://www.ipiqblog.com/wp-content/uploads/sites/47/2024/05/23-1247.OPINION.5-10-2023_2124577-Vanda-v.-Teva-2.pdf
- https://www.supremecourt.gov/DocketPDF/23/23-768/303255/20240318102817346_Final%20PDF%20A%20Tasimelteon%20Respondents%20Brief%20in%20Opp.pdf
- https://casetext.com/case/vanda-pharm-v-teva-pharm-us-2
