Under the Heron Therapeutics and Mylan patent settlement announced on May 6, 2025, Mylan Pharmaceuticals received a license to sell generic versions of CINVANTI and APONVIE in the United States beginning June 1, 2032. That is roughly three years before Heron’s patents covering the two injectable anti-nausea drugs are scheduled to expire in 2035.1Heron Therapeutics. Heron Therapeutics Announces Settlement With Mylan Related to CINVANTI and APONVIE Patent Litigations
What the Deal Gives Each Side
Heron granted Mylan, a subsidiary of Viatris, a license under its Orange Book-listed patents to market generic versions of CINVANTI (aprepitant) injectable emulsion and APONVIE (aprepitant) injectable emulsion starting June 1, 2032, “or earlier under certain customary circumstances.”2PR Newswire. Heron Therapeutics Announces Settlement With Mylan Related to CINVANTI and APONVIE Patent Litigations Neither company disclosed royalties, upfront payments, or any other financial terms.
Both sides agreed to file a stipulation and order of dismissal in the U.S. District Court for the District of Delaware.1Heron Therapeutics. Heron Therapeutics Announces Settlement With Mylan Related to CINVANTI and APONVIE Patent Litigations Judge William C. Bryson issued an order the same day the settlement was announced, memorializing the deal and allowing either company to renew its allegations if necessary.3Bloomberg Law. Viatris Can Sell Copies of Heron Nausea Drugs in 2032 After Deal The consolidated case was formally terminated on August 18, 2025.4CourtListener. Heron Therapeutics, Inc. v. Mylan Pharmaceuticals, Inc.
The Lawsuits Behind the Settlement
Mylan set the dispute in motion by filing abbreviated new drug applications with the FDA to sell generic versions of both drugs before Heron’s patents expired. Heron sued in September 2023 over CINVANTI and again in January 2024 over APONVIE, both times in the District of Delaware.1Heron Therapeutics. Heron Therapeutics Announces Settlement With Mylan Related to CINVANTI and APONVIE Patent Litigations The APONVIE case (No. 1:24-cv-00043) was consolidated with the earlier CINVANTI suit (No. 1:23-cv-01015-WCB) in late January 2024. Mylan filed an answer and counterclaim in February 2024, but the case never reached trial.4CourtListener. Heron Therapeutics, Inc. v. Mylan Pharmaceuticals, Inc.
Why June 2032
The patents in dispute cover the injectable emulsion formulation of aprepitant, including the drug’s physical stability, the ratios of ingredients such as egg yolk lecithin and soybean oil, and pH characteristics.5U.S. District Court for the District of Delaware. Heron Therapeutics, Inc. v. Fresenius Kabi USA, LLC Opinion At least two of them, U.S. Patent Nos. 9,561,229 and 9,974,794, have been identified in related litigation as key Heron patents, and both expire in 2035.6Heron Therapeutics. U.S. District Court Upholds Validity of CINVANTI Patents
The June 1, 2032 date gives Mylan a runway of about three years before those patents lapse. Settlements of this kind are common under the Hatch-Waxman framework. When a generic filer submits an ANDA with a Paragraph IV certification asserting that the brand company’s patents are invalid or won’t be infringed, the brand company can sue, and the resulting litigation often ends with a negotiated pre-expiration entry date that avoids the cost and uncertainty of trial. Neither Heron nor Mylan explained publicly why 2032 was the specific date chosen.
What CINVANTI and APONVIE Are
Both drugs use the same injectable emulsion of aprepitant, a substance P/neurokinin-1 receptor antagonist that prevents nausea and vomiting. CINVANTI, given as a 30-minute intravenous infusion or a 2-minute injection, prevents chemotherapy-induced nausea and vomiting.7Heron Therapeutics. Heron Therapeutics Homepage APONVIE, a 30-second intravenous injection, was approved by the FDA on September 16, 2022, to prevent postoperative nausea and vomiting in adults.8Heron Therapeutics. Heron Therapeutics Announces U.S. FDA Approval of APONVIE
CINVANTI is the far larger product. It generated approximately $96.8 million in net revenue in 2025, compared with $11.6 million for APONVIE.9Heron Therapeutics. Heron Therapeutics Announces Fourth Quarter and Full Year 2025 Financial Results CINVANTI held roughly 25% of the NK1 receptor antagonist market for chemotherapy-related nausea prevention in the first quarter of 2026.10GlobeNewsWire. Heron Therapeutics Announces First Quarter 2026 Financial Results and Reaffirms Guidance
Other Generic Challenges to CINVANTI
The Mylan settlement does not resolve every challenge Heron has faced on these patents. Fresenius Kabi filed its own ANDA for a generic CINVANTI, and after Heron sued in July 2022 the District of Delaware ruled in Heron’s favor in December 2024, finding U.S. Patent Nos. 9,561,229 and 9,974,794 valid and infringed by the proposed Fresenius product. Heron sought an order blocking a Fresenius launch through 2035, subject to appeal.6Heron Therapeutics. U.S. District Court Upholds Validity of CINVANTI Patents11RTT News. Heron Therapeutics Wins Patent Lawsuit Against Fresenius Kabi for CINVANTI
Heron also sued Baxter Healthcare Corporation in the District of Delaware in December 2025, asserting infringement of 13 patents.12CourtListener. Heron Therapeutics, Inc. v. Baxter Healthcare Corporation That case also settled, and the court dismissed the litigation on April 28, 2026. The Baxter settlement terms have not been publicly disclosed.13Heron Therapeutics. Heron Therapeutics Announces First Quarter 2026 Financial Results