We are developing YUTREPIA under the 505(b)(2) regulatory pathway with Tyvaso as the reference listed drug. Accordingly, under the Hatch-Waxman Amendments to the Food, Drug and Cosmetic Act, we were required to, in the NDA for YUTREPIA, certify that patents listed in the Orange Book for Tyvaso are invalid, unenforceable or will not be infringed by the manufacture, use or sale of YUTREPIA. Two of these patents are U.S. Patent No. 9,604,901 (the "‘901 Patent"), entitled "Process to Prepare Treprostinil, the Active Ingredient in Remodulin", and U.S. Patent No. 9,593,066 (the "‘066 Patent"), entitled "Process to Prepare Treprostinil, the Active Ingredient in Remodulin", both of which are owned by United Therapeutics. A notice of the paragraph IV certification was required to be provided to United Therapeutics as the owner of the patents that are the subject of the certification to which the NDA for YUTREPIA refers. In June 2020, United Therapeutics, as the holder of such patents, asserted a patent challenge directed to the ‘901 Patent and the ‘066 Patent by filing a complaint against us in the U.S. District Court for the District of Delaware (Case No. 1:20-cv-00755-RGA) (the "Original Hatch-Waxman Litigation").
In July 2020, the U.S. Patent and Trademark Office (the "USPTO") issued U.S. Patent No. 10,716,793 (the "‘793 Patent"), entitled "Treprostinil Administration by Inhalation", to United Therapeutics. In July 2020, United Therapeutics filed an amended complaint in the Original Hatch-Waxman Litigation asserting infringement of the ‘793 Patent by the practice of YUTREPIA.
In June 2021, the Court held a claim construction hearing. Based on the Court's construction of the claim terms, United Therapeutics filed a stipulation of partial judgment with respect to the ‘901 Patent in December 2021 under which United Therapeutics agreed to the entry of judgment of our non-infringement of the ‘901 Patent. United Therapeutics did not file an appeal with respect to the ‘901 Patent.
Trial proceedings in the Original Hatch-Waxman Litigation were held in March 2022. In August 2022, Judge Andrews, who was presiding over the Original Hatch-Waxman Litigation, issued an opinion that claims 1, 2, 3, 6 and 9 of the ‘066 Patent were invalid, that the remaining asserted claims of the ‘066 Patent were not infringed by us, and that all of the asserted claims of the ‘793 Patent were both valid and infringed by us, based on the arguments we presented in the Original Hatch-Waxman Litigation. In September 2022, Judge Andrews entered a final judgment in the Original Hatch-Waxman Litigation that incorporated the findings from his opinion and ordered that the effective date of any final approval by the FDA of YUTREPIA shall be a date which is not earlier than the expiration date of the '793 Patent, which will be in 2027. Both we and United Therapeutics appealed Judge Andrews' decision to the United States Court of Appeals for the Federal Circuit. On July 24, 2023, the United States Court of Appeals for the Federal Circuit affirmed Judge Andrews' decision with respect to both the ‘066 Patent and the ‘793 Patent.
In March 2020, we filed two petitions for inter partes review with the Patent Trial and Appeal Board, or the PTAB, of the USPTO. One petition was for inter partes review of the ‘901 Patent, seeking a determination that the claims in the ‘901 Patent are invalid, and a second petition is for inter partes review of the ‘066 Patent, seeking a determination that the claims in the ‘066 Patent are invalid. In October 2020, the PTAB instituted an inter partes review of the ‘901 Patent and concurrently denied institution on the ‘066 Patent, stating that the ‘066 petition has not established a reasonable likelihood that it would prevail in showing that at least one of the challenged claims is unpatentable. In October 2021, the PTAB issued a final written decision concluding that seven of the claims in the ‘901 patent were unpatentable, leaving only the narrower dependent claims 6 and 7, both of which require actual storage at ambient temperature of treprostinil sodium. In November 2021, United Therapeutics submitted a rehearing request with respect to the PTAB's decision in the inter partes review of the ‘901 patent. The rehearing request was denied in June 2022. In August 2022, United Therapeutics appealed the decision of the PTAB with respect to the ‘901 Patent to the United States Court of Appeals for the Federal Circuit. Oral argument was held in February 2024, and the appeal remains pending.
In January 2021, we filed a petition with the PTAB for inter partes review of the ‘793 Patent, seeking a determination that the claims in the ‘793 Patent are invalid. In August 2021, the PTAB instituted an inter partes review of the ‘793 Patent, finding that we had demonstrated a reasonable likelihood that we would prevail with respect to showing that at least one challenged claim of the ‘793 Patent is unpatentable as obvious over the combination of certain prior art cited by us in our petition to the PTAB. In July 2022, the PTAB ruled in our favor, concluding that based on the preponderance of the evidence, all the claims of the ‘793 Patent have been shown to be unpatentable. In August 2022, United Therapeutics submitted a rehearing request with respect to the PTAB's decision in the inter partes review of the ‘793 Patent. The rehearing request was denied in February 2023. In April 2023, United Therapeutics appealed the decision of the PTAB with respect to the ‘793 Patent to the United States Court of Appeals for the Federal Circuit. In December 2023, the United States Court of Appeals for the Federal Circuit affirmed the earlier decision by the PTAB, which found all claims of the ‘793 Patent to be unpatentable due to the existence of prior art cited by us in inter partes review proceedings. As a result of this decision by the United States Court of Appeals for the Federal Circuit, in December 2023, we filed a motion for Judge Andrews to set aside the injunction he issued in the Original Hatch-Waxman Litigation. The motion has been fully briefed and remains pending. In January 2024, United Therapeutics filed a request for rehearing of the decision by the United States Court of Appeals for the Federal Circuit. The request for rehearing was denied on March 12, 2024. United Therapeutics has the right to file a petition for a writ of certiorari to seek an appeal with the United States Supreme Court, but no such petition has been filed to date.
In connection with an amendment to our NDA filed in July 2023 to add PH-ILD as an indication for YUTREPIA, we provided a new notice of the paragraph IV certification to United Therapeutics as the owner of the patents that are the subject of the certification to which the NDA for YUTREPIA refers. As a result, in September 2023, United Therapeutics filed a second complaint for patent infringement against us in the U.S. District Court for the District of Delaware (Case No. 1:23-cv-00975-RGA) (the "New Hatch-Waxman Litigation"), again asserting infringement by the Company of the ‘793 Patent. In November 2023, the U.S. Patent and Trademark Office (the USPTO) issued U.S. Patent No. 11,826,327, or the ‘327 Patent, entitled "Treatment for Interstitial Lung Disease", to United Therapeutics. On November 30, 2023, United Therapeutics filed an amended complaint in the New Hatch-Waxman Litigation asserting infringement of the ‘327 Patent by the practice of YUTREPIA based on the amended NDA. In January 2024, we filed an answer, counterclaims and a partial motion to dismiss the claims related to the ‘793 Patent as a result of the decision by the United States Court of Appeals for the Federal Circuit to affirm the PTAB's finding that the '793 patent is unpatentable. In February 2024, United Therapeutics stipulated to the dismissal of the claims in the New Hatch-Waxman Litigation related to the ‘793 Patent. In February 2024, United Therapeutics also filed a motion seeking a preliminary injunction to prevent us from manufacturing, marketing, storing, importing, distributing, offering for sale, and/or selling YUTREPIA for the treatment of PH-ILD. Briefing on the motion for preliminary injunction is ongoing, and the motion remains pending.
Although we do not believe United Therapeutics is entitled to a new 30-month stay or a preliminary injunction in connection with the New Hatch-Waxman Litigation, it is possible that the Court could rule that a new mandatory 30-month delay has been triggered with respect to the approval of the 505(b)(2) NDA application or that a preliminary injunction is warranted.
In February 2024, United Therapeutics also filed a lawsuit against the FDA, challenging the FDA's acceptance of our amended NDA for review (the "FDA Litigation"). On March 4, 2024, United Therapeutics filed a motion for a temporary restraining order in the FDA Litigation, seeking to enjoin the FDA from approving our NDA for YUTREPIA with respect to the indication to treat PH-ILD. Briefing on the motion for a temporary restraining order is ongoing, and the motion remains pending. Although we do not believe the arguments of United Therapeutics have merit, it is possible that the Court could rule that the FDA must reject the amendment to the YUTREPIA NDA to add PH-ILD to the label, in which case we may be required to later file a supplement to our NDA to add PH-ILD to the label.
In addition, United Therapeutics may seek to assert newly issued patents against us, including U.S. Patent Number 11,723,887, and may seek to enjoin the FDA from granting final approval to YUTREPIA or enjoin us from launching YUTREPIA through one or more additional legal proceedings.
As a result of this litigation, we may be subject to significant delay and incur substantial additional costs in litigation before we are able to commercialize YUTREPIA, if at all. In addition, if United Therapeutics is successful in any of its appeals or requests for rehearing, we may be unable to commercialize YUTREPIA until the expiration of United Therapeutics' patents, which could materially harm our business. Also, if United Therapeutics is successful in obtaining a preliminary injunction or temporary restraining order in the New Hatch-Waxman Litigation or the FDA Litigation, we could be limited to commercializing YUTREPIA only for the PAH indication for an extended time period.
In December 2021, United Therapeutics filed a complaint in the Superior Court in Durham County, North Carolina, alleging that we and a former United Therapeutics employee, who later joined us as an employee many years after terminating his employment with United Therapeutics, conspired to misappropriate certain trade secrets of United Therapeutics and engaged in unfair or deceptive trade practices. In January 2024, our co-defendant in the lawsuit filed a motion to dismiss all claims. The motion is being briefed and remains pending. Fact discovery in the case has concluded, and expert discovery is in process.
Success in the lawsuits or inter partes review proceedings with respect to some patents or some claims in a given patent does not mean that we will be similarly successful upon appeal of those decisions. In addition, success with respect to a given patent or patent claim in one proceeding does not mean we will be similarly successful with respect to that same patent or patent claim in another proceeding.
If, after the appeals process has been completed, we are found to infringe, misappropriate or otherwise violate any United Therapeutics' intellectual property rights, we could be required to obtain a license from United Therapeutics to continue developing and marketing YUTREPIA. However, we may not be able to obtain any required license on commercially reasonable terms or at all. We could be found liable for monetary damages, including treble damages and attorneys' fees if we are found to have willfully infringed a patent or to have misappropriated a trade secret of United Therapeutics. In addition, we may be forced to redesign YUTREPIA to avoid infringement.