Xeris Sues Torrent, Cycle, LeMed, and Rising, Alleging Generic KEVEYIS Labels Induce Infringement of a Newly Issued Patent.

Two suits filed the day the patent issued

Xeris Pharmaceuticals, Inc. filed two patent infringement complaints in the District of New Jersey on October 13, 2026, the same day the USPTO issued U.S. Patent 12,758,502. Xeris Pharmaceuticals, Inc. v. Torrent Pharma Inc., No. 2:26-cv-13355, names Torrent Pharma Inc., Torrent Pharmaceuticals Limited, Cycle Pharmaceuticals Limited, LeMed Pharmacy III, LLC, and LeMed Specialty Pharmacy Arizona, LLC. Xeris Pharmaceuticals, Inc. v. Rising Pharma Holdings, Inc., No. 2:26-cv-13358, names Rising Pharma Holdings, Inc. d/b/a Rising Pharmaceuticals and Rising Pharma Specialities Pvt. Ltd. Both complaints assert claim 1 of the '502 patent, a method of giving dichlorphenamide to a patient who is being given famotidine, against generic dichlorphenamide 50 mg tablets that FDA has already approved. Both rest on the same theory: that drug interaction language in the generic labels, which the complaints say matches the label for Xeris's KEVEYIS, induces doctors, pharmacists, and patients to practice the claimed method.

Both cases carry the initials of U.S. District Judge Brian R. Martinotti and Magistrate Judge Leda Dunn Wettre in their case numbers, and the Rising complaint was filed with a related case designation. Summonses issued in both cases on October 14, 2026.

KEVEYIS and the parties

According to the complaints, KEVEYIS (dichlorphenamide) is an oral carbonic anhydrase inhibitor and the first FDA-approved medicine for primary periodic paralysis, a rare hereditary neuromuscular disease marked by attacks of muscle weakness or temporary paralysis, and it is indicated for both the hyperkalemic and hypokalemic forms and related variants. FDA approved NDA No. 011366 for KEVEYIS on August 7, 2015, and granted it orphan drug exclusivity. Xeris holds the NDA and markets KEVEYIS in the United States. The complaints describe Xeris as a Delaware corporation based in Chicago, Illinois, that owns all rights, title, and interest in the '502 patent.

The Torrent complaint alleges, on information and belief, that Torrent Pharma Inc. is a Delaware corporation based in Basking Ridge, New Jersey, and a wholly owned subsidiary of Torrent Pharmaceuticals Limited, an Indian company headquartered in Ahmedabad, Gujarat, India; that Cycle Pharmaceuticals Limited is a United Kingdom company based in Cambridge, United Kingdom; that LeMed Pharmacy III, LLC is a New York limited liability company based in the Bronx, New York; and that LeMed Specialty Pharmacy Arizona, LLC is a New York limited liability company registered to do business in New Jersey as a foreign limited liability company.

The Rising complaint alleges, on information and belief, that Rising Pharma Holdings, Inc. is a Delaware corporation based in East Brunswick, New Jersey, and a wholly owned subsidiary of Rising Pharma Specialities Pvt. Ltd., a private limited company organized under the laws of India and headquartered in Hyderabad, Telangana, India, and that the two companies collaborate on the development, regulatory approval, marketing, and sale of generic drugs in the United States.

The patent and the asserted claim

U.S. Patent 12,758,502, titled Compositions and Methods of Use, issued October 13, 2026, from Application No. 17/151,405, filed January 18, 2021. It has a single claim. Its face states a patent term adjustment of 1,290 days under 35 U.S.C. 154(b) and that the patent is subject to a terminal disclaimer. Claim 1 recites a method of administering dichlorphenamide to treat primary hyperkalemic periodic paralysis or primary hypokalemic periodic paralysis in a human subject who is being administered famotidine for the treatment of a disease or disorder. The method comprises discontinuing administration of the famotidine and administering dichlorphenamide in tablet form at an initial dose of 50 mg, once or twice daily, thereby avoiding concomitant administration of famotidine and dichlorphenamide.

Each complaint says Xeris timely submitted the '502 patent for listing in the Orange Book for KEVEYIS. Each alleges, on information and belief, that the defendants have known of the patent since at least June 11, 2026, when Xeris publicly announced a notice of allowance on the application and said it would submit the patent for Orange Book listing, and that the defendants monitor Xeris's patent activity on KEVEYIS. Xeris also pleads notice letters from its counsel dated October 13, 2026: one to Rising, and one each to Torrent, Cycle, and LeMed. The Rising letter is Exhibit 2 to the Rising complaint. The Torrent, Cycle, and LeMed letters, Exhibits 2 through 4 to the Torrent complaint, are not on the public docket.

The labeling theory

Both complaints quote section 7.2 of the KEVEYIS prescribing information, which states that "dichlorphenamide is an inhibitor of OAT1 transporters" and that use with drugs sensitive to OAT1 inhibition, naming methotrexate, famotidine, and oseltamivir as examples, "is not recommended," and section 17, which tells providers to instruct patients to report all of the drugs and over-the-counter medications they take. The complaints allege that the approved labeling for each generic product carries the same language and is identical in this respect to the KEVEYIS label, and that the "not recommended" statement is a clear, affirmative instruction to discontinue famotidine before giving dichlorphenamide. They note that famotidine is widely sold over the counter, so that a patient's use may come to light only if the patient discloses it.

For direct infringement, the complaints plead alternative theories. Under the first, healthcare providers or pharmacists are the direct infringers, with the steps performed by others attributed to whichever of them directs the course of treatment. Under the second, patients directly infringe by stopping famotidine and taking dichlorphenamide as their providers or pharmacists direct. The complaints allege that the defendants knowingly and with specific intent induce that infringement under 35 U.S.C. 271(b).

The complaints allege that the label language is loaded into automated pharmacy drug utilization review systems, which generate an interaction alert when a dichlorphenamide prescription is entered for a patient whose profile lists famotidine. They cite the federal Medicaid drug use review provision, 42 U.S.C. 1396r-8(g)(2)(A), and a New Jersey pharmacy regulation, N.J.A.C. 13:39-7.21, as requiring pharmacists to screen for interactions and counsel patients. They allege, on information and belief, that pharmacists dispensing the generic tablets now routinely detect the interaction and respond by contacting the prescriber, counseling the patient, or declining to dispense until the interaction is resolved. They also allege, on information and belief, that the generic companies' adverse event reporting obligations under 21 C.F.R. 314.80 create a feedback loop that reinforces their knowledge that the label causes the claimed method to be practiced, and that the companies benefit when the warning is followed, because no adverse interaction occurs, they face no product liability exposure, and their federal preemption defense stays intact.

Each complaint alleges, on information and belief, that the generic applicant made no attempt to "skinny label" under 21 U.S.C. 355(j)(2)(A)(viii) to omit the section 7.2 language, and says that keeping it supports an inference of intent. That provision lets a generic applicant submit a statement that a listed method-of-use patent does not claim a use for which the applicant is seeking approval. Each complaint also alleges that the infringement has been deliberate and willful, and that the defendants have kept marketing and selling the generic tablets, without seeking to change their labeling or promotional materials, since receiving the notice letters.

Torrent, Cycle, and the LeMed pharmacies

According to the Torrent complaint, Torrent Pharma Inc. submitted ANDA No. 215924 for dichlorphenamide 50 mg tablets, and FDA approved it on December 29, 2022. The complaint says Torrent announced on April 6, 2023, that it had begun shipping the generic product in the United States, and alleges, on information and belief, that Torrent has sold it since at least April 2023 through traditional wholesale channels to retail and specialty chain pharmacies. It alleges that as of at least May 10, 2024, Torrent and Cycle agreed to market and sell dichlorphenamide 50 mg tablets under the trade name Ormalvi under the same ANDA, and that Cycle's public materials identify Ormalvi as a Torrent Pharma trademark. The complaint accuses both the Torrent-labeled tablets and Ormalvi.

The complaint alleges that on or around May 14, 2024, Cycle entered into an agreement with LeMed to serve as the exclusive specialty pharmacy partner for the distribution of Ormalvi, and, on information and belief, that LeMed has since managed and dispensed Ormalvi to patients nationwide. It alleges, on information and belief, that LeMed Pharmacy III and LeMed Specialty Pharmacy Arizona each dispense, distribute, offer for sale, and sell pharmaceutical products including Ormalvi throughout the United States, including in New Jersey, and it says Cycle distributes Ormalvi exclusively through LeMed specialty pharmacies. The complaint refers to the two LeMed companies together as "LeMed."

For Ormalvi, the complaint groups Cycle, Torrent, and LeMed as the "Ormalvi Defendants" and alleges inducement that goes beyond the label. It points to a Patient Initiation Brochure that Cycle created, which tells patients: "Tell your doctor if you are taking drugs that are sensitive to OAT1 inhibition such as methotrexate, famotidine or oseltamivir." It points to Cycle Vita, a hub support program run by Cycle whose Access Specialists and Clinical Education Managers provide patients with clinical education and medication administration support, including through calls Cycle initiates and monthly calls during therapy, and alleges, on information and belief, that this education covers the famotidine interaction. It alleges that the Ormalvi Defendants route every Ormalvi prescription through LeMed, which, according to its website as quoted in the complaint, provides patient education during intake, at the start of new therapy, and through monthly reassessment calls, with pharmacists on call 24 hours a day. It alleges, on information and belief, that LeMed's counseling includes the interaction between dichlorphenamide and famotidine and that LeMed's pharmacists are currently screening for and counseling Ormalvi patients on it.

The complaint says no regulation required the brochure, the Cycle Vita program, or the exclusive LeMed arrangement, and contrasts that model with the wholesale distribution Torrent uses for its own labeled tablets. Venue over LeMed is pleaded on the ground that it has induced acts of infringement in the District, and personal jurisdiction over LeMed Specialty Pharmacy Arizona rests in part on its New Jersey registration.

Rising and the alternative ANDA count

According to the Rising complaint, Rising Pharma Holdings submitted ANDA No. 218783, and FDA approved it on November 18, 2025. The complaint alleges, on information and belief, that Rising has offered for sale and sold the generic tablets, or is preparing to, that the product has been available for ordering in commercial drug databases and pharmacy systems since at least early 2026, and that prescriptions for it have been filled. It cites a new drug introduction report that Rising Pharma Holdings filed with the Vermont Attorney General's Office on or about March 4, 2026, which lists a wholesale acquisition cost of $25,628.07 for a 100-tablet bottle and an estimated patient volume of 200. It alleges that Rising listed the product in drug pricing compendia at a substantial discount to the KEVEYIS wholesale acquisition cost, and alleges, on information and belief, that the listing lets payers and pharmacy benefit managers demand larger rebates, discounts, and price concessions from Xeris. Xeris attributes revenue declines and unfavorable net pricing to generic competition and alleges that KEVEYIS net revenue declined in each of fiscal years 2024 and 2025.

Count I pleads induced infringement under section 271(b). Count II, pleaded in the alternative and in addition, alleges that Rising Pharma Holdings' submission of ANDA No. 218783 was itself an act of infringement under 35 U.S.C. 271(e)(2)(A), because it sought approval to sell a product whose use is claimed in the patent before the patent expires. It alleges, on information and belief, that the ANDA shows bioequivalence to KEVEYIS and that the defendants were actively involved in preparing, submitting, and prosecuting it, or will be involved in selling the product. To the extent a court determines that section 271(e)(2) provides a basis for liability on these facts, Xeris seeks the remedies of section 271(e)(4), including an order that the effective date of approval of the ANDA be no earlier than the patent's expiration.

Relief requested and counsel

Both prayers ask for a judgment that the defendants have induced, are inducing, and will continue to induce infringement; a permanent injunction under 35 U.S.C. 283 against making, using, selling, offering to sell, marketing, distributing, or importing the accused tablets, or inducing any of those acts; a declaratory judgment that those activities actively induce infringement; damages under 35 U.S.C. 284, including lost profits or a reasonable royalty, with interest; a finding of willfulness and enhanced damages; an exceptional case finding with attorney fees under 35 U.S.C. 285; and costs. The Rising prayer also asks for a judgment of infringement under section 271(e)(2) and an order under section 271(e)(4)(A) that any approval of ANDA No. 218783 take effect no earlier than the patent's expiration, including any extensions. Both complaints demand a jury trial.

Charles H. Chevalier of FBT Gibbons LLP in Newark, New Jersey, signed both complaints, with Michael V. Caracappa and Christian Villatoro of the same firm; Magnolia S. Joodi of the firm also appears on the Rising complaint's signature block. Of counsel are David P. Frazier, Kelly A. Welsh, and Rozzi Upton of Latham & Watkins LLP in Washington, D.C., Marc N. Zubick of the firm's Chicago office, and Sophia Lam of its New York office.

What to watch next

On October 20, 2026, Xeris filed two more District of New Jersey complaints, captioned against Torrent Pharma Inc. (No. 2:26-cv-13654) and Rising Pharma Holdings, Inc. d/b/a Rising Pharmaceuticals (No. 2:26-cv-13655), which are not on the public docket. Watch for the defendants' answers or Rule 12 motions in the October 13 cases, including any challenge to the theory that a generic label's drug interaction warning induces infringement of a method-of-use claim, and for any motion to consolidate or coordinate the Xeris cases. The cases can end at any time, including by settlement or voluntary dismissal.