Amoxicillin/Clarithromycin/Vonoprazan

FLORHAM PARK, N.J., Feb. 09, 2023 (GLOBE NEWSWIRE) -- Phathom Pharmaceuticals Inc. (Nasdaq: PHAT), a biopharmaceutical company focused on developing and commercializing novel treatments for gastrointestinal diseases, today announced regulatory updates for its approved products, VOQUEZNA™ TRIPLE PAK™ and VOQUEZNA DUAL PAK™, approved in the U.S. for the treatment of H. pylori infection, and its pending New Drug Application (NDA) for vonoprazan for the treatment of erosive esophagitis. Phathom has received complete response letters from the U.S. Food and Drug Administration (FDA) relating to its erosive esophagitis NDA and H. pylori post approval supplement, both of which address specifications and controls for a nitrosamine drug substance related impurity, N-nitroso-vonoprazan (NVP), that was detected in the initial commercial launch materials of VOQUEZNA TRIPLE PAK and VOQUEZNA DUAL PAK. These letters formalize FDA’s request, announced by the Company last month, that Phathom provide additional stability data to demonstrate that levels of the impurity previously found in vonoprazan drug product will remain at or below the daily acceptable intake throughout the proposed shelf life of the product. No additional deficiencies were cited by the FDA in either letter. Phathom has conducted extensive root cause investigations regarding the trace levels of the impurity since it was detected and has implemented mitigation measures to control the levels of NVP below the acceptable intake. Phathom expects to meet with the FDA in the first quarter of this year to discuss the resubmission plan and timeline that the Company believes will lead to approval and launch of products containing vonoprazan. “We remain encouraged with the progress we have made in generating additional stability data to meet FDA’s request and are eagerly awaiting our meeting with the FDA anticipated later this quarter to discuss our ongoing efforts, share our data, and gain alignment on resubmission and potential approval timelines,” said Terrie Curran, President and Chief Executive Officer of Phathom. “We are pleased that no other review issues were cited related to our erosive esophagitis NDA and that our labeling discussions continued to progress since our announcement last month, resulting in a near final label. We are confident that our ongoing stability program will generate the required data and will clear the pathway to potential approval and launch of these important products for patients in need of new treatment options for erosive esophagitis and H. pylori infection.” About Phathom Pharmaceuticals, Inc. Phathom Pharmaceuticals is a biopharmaceutical company focused on the development and commercialization of novel treatments for gastrointestinal diseases and disorders. Phathom has in-licensed the exclusive rights in the United States, Europe, and Canada to vonoprazan, a first-in-class potassium-competitive acid blocker (PCAB). For more information about Phathom, visit the Company’s website at and follow the Company on LinkedIn and Twitter. Forward-Looking Statements Phathom cautions you that statements contained in this press release regarding matters that are not historical facts are forward-looking statements. These statements are based on the Company’s current beliefs and expectations. Such forward-looking statements include, but are not limited to, statements regarding Phathom’s expectations of generating stability data necessary to support the proposed shelf life of vonoprazan and the potential approval of its erosive esophagitis NDA and post approval supplement for its H. pylori NDAs, and anticipated product launches in H. pylori and erosive esophagitis. The inclusion of forward-looking statements should not be regarded as a representation by Phathom that any of its plans will be achieved. Actual results may differ from those set forth in this press release due to the risks and uncertainties inherent in Phathom’s business, including, without limitation: Phathom may be unable to generate the required data to meet the acceptable intake (AI) of its nitrosamine impurity, or may be unable to reduce the impurity to an acceptable level throughout the shelf life of the product, to obtain approval for its erosive esophagitis NDA or to bring vonoprazan to market for patients with erosive esophagitis, if approved, or for patients with H. pylori; risks associated with product manufacturing or formulation changes required to be made in connection with achieving the AI; the FDA may disagree that the existing safety and efficacy data, together with additional data, is sufficient to approve the erosive esophagitis NDA or supplements to the H. pylori NDAs; the inherent risks of clinical development of vonoprazan; Phathom’s dependence on third parties in connection with product manufacturing, research and preclinical and clinical testing; regulatory developments in the United States and foreign countries; unexpected adverse side effects or inadequate efficacy of vonoprazan that may limit its development, regulatory approval and/or commercialization, or may result in recalls or product liability claims; Phathom’s ability to access additional capital under its term loan facility and royalty interest finance agreements is subject to certain conditions; Phathom’s ability to obtain and maintain intellectual property protection for vonoprazan; Phathom’s ability to comply with its license agreement with Takeda; Phathom’s ability to maintain undisrupted business operations due to the ongoing spread of the COVID-19 coronavirus, including delaying or otherwise disrupting its clinical trials, manufacturing and supply chain, and other risks described in the Company’s prior press releases and the Company’s filings with the Securities and Exchange Commission (SEC), including under the heading “Risk Factors” in the Company’s Annual Report on Form 10-K and any subsequent filings with the SEC. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof, and Phathom undertakes no obligation to update such statements to reflect events that occur or circumstances that exist after the date hereof. All forward-looking statements are qualified in their entirety by this cautionary statement, which is made under the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. MEDIA CONTACT Nick Benedetto 1-877-742-8466 media@phathompharma.com INVESTOR CONTACT Eric Sciorilli 1-877-742-8466 ir@phathompharma.com

Phathom Pharmaceuticals is having a good week as the U.S. Food and Drug Administration approved two of its products for bacterial illnesses in adults. Voquezna Triple Pak and Voquezna Dual Pak were both given the green light to treat Helicobacter pylori (H. pylori). The products' New Drug Applications had been granted priority review and also designated as Qualified Infectious Diseases Products. Voquezna Triple Pak is made up of vonoprazan tablets, amoxicillin capsules and clarithromycin tablets, while the Dual Pak consists of vonoprazan tablets and amoxicillin capsules. Both are designed to address the H. pylori bacterial pathogen, which can lead to serious complications like non-cardia gastric cancer and peptic ulcer if left untreated. There are around 115 million people affected by this pathogen in the U.S. and eradication rates are below 80%. Vonoprazan, a potassium-competitive acid blocker, is the first innovative acid suppressant from a new drug classification in the U.S. over the last three decades. The FDA's decision is based on stellar results from the Phase III PHALCON-HP trial, which covered 1,046 patients with H. pylori. Both treatment regimens demonstrated non-inferiority to lansoprazole triple therapy with no clarithromycin or amoxicillin resistant strain of the bacterium at baseline. Triple Pak demonstrated an 84.7% eradication rate versus 78.8% in the lansoprazole group, while Dual Pak showed a 78.5% eradication rate compared to lansoprazole triple's 78.8%. Among the same patients, including those with clarithromycin-resistant strains of H. pylori, Voquezna Triple Pak logged an 80.8% eradication rate compared to 68.5% in lansoprazole with amoxicillin and clarithromycin. Those who received a Dual Pak logged 77.2% versus 68.5%. Some adverse events were observed but were not much different from the AEs seen in lansoprazole triple therapy arms, such as dysgeusia, diarrhea, hypertension, abdominal pain, vulvovaginal candidiasis and nasopharyngitis. Phathom notes that both products are not recommended for patients with hypersensitivity to amoxicillin or vonoprazan, other beta-lactams and those receiving drugs that contain rilpivirine. The clarithromycin component also makes them contraindicated in those with allergies to the drug or other similar antibiotic, those with a history of hepatic dysfunction and others. "H. pylori eradication rates continue to decline in part due to antibiotic resistance, inadequate acid suppression and complex treatment regimens, resulting in treatment failures and complications for patients. New therapies that have the potential to address the limitations of current treatments are needed and we look forward to bringing these innovative vonoprazan-based treatment options to the millions of H. pylori sufferers in the U.S.," Terri Curran, president and chief executive officer of Phathom, said in a statement. Voquezna Triple Pak and Voquezna Dual Pak will be out in the U.S. market by the third quarter of 2022. Phathom will be marketing the products exclusively.