Announcement • Jun 23
Phathom Pharmaceuticals Completes Enrollment In Phase 2 pHalcon-EoE-201 Clinical Trial Of VOQUEZNA In Eosinophilic Esophagitis
Phathom Pharmaceuticals, Inc. has completed enrollment in its Phase 2 pHalcon-EoE-201 clinical trial evaluating VOQUEZNA (vonoprazan) tablets as an investigational treatment for eosinophilic esophagitis (EoE) in adults. The study has enrolled 95 patients at 41 U.S. sites. Topline results are anticipated in the fourth quarter 2026. The pHalcon-EoE-201 study is a two-part, randomized, double-blind, placebo-controlled Phase 2 study. In Part 1, 95 adults with endoscopically confirmed EoE and dysphagia have been randomized evenly to receive VOQUEZNA 20 mg or placebo once daily for 12 weeks. Patients who complete Part 1 are eligible to enter Part 2, a 12-week extension phase in which all participants receive VOQUEZNA 20 mg once daily. If the Phase 2 pHalcon-EoE-201 study generates positive results, Phathom expects to discuss with FDA potential future development plans in EoE, including pediatric evaluation that could potentially support an extension of regulatory exclusivity. VOQUEZNA (vonoprazan) is a potassium-competitive acid blocker (PCAB) indicated in adults for the healing of all grades of Erosive Esophagitis (Erosive Gastroesophageal Reflux Disease or Erosive GERD) and relief of heartburn associated with Erosive GERD, to maintain healing of all grades of Erosive GERD and relief of heartburn associated with Erosive GERD, for the relief of heartburn associated with Non-Erosive GERD, in combination with amoxicillin and clarithromycin for the treatment of Helicobacter pylori (H. pylori) infection, and in combination with amoxicillin for the treatment of H. pylori infection. VOQUEZNA is contraindicated in patients with a known hypersensitivity to vonoprazan or any component of VOQUEZNA, or in patients receiving rilpivirine-containing products. Presence of Gastric Malignancy: In adults, symptomatic response to therapy with VOQUEZNA does not preclude the presence of gastric malignancy. Acute Tubulointerstitial Nephritis: Acute tubulointerstitial nephritis (TIN) has been reported with VOQUEZNA. Clostridioides difficile-Associated Diarrhea: Published observational studies suggest that proton pump inhibitors (PPIs) may be associated with an increased risk of Clostridioides difficile-associated diarrhea (CDAD), especially in hospitalized patients. VOQUEZNA may also increase the risk of CDAD. Bone Fracture: Several published observational studies suggest that PPI therapy may be associated with an increased risk for osteoporosis-related fractures of the hip, wrist, or spine, especially in patients receiving high dose (multiple daily doses) and long-term therapy (a year or longer). Bone fracture, including osteoporosis-related fracture, has also been reported with vonoprazan. Severe Cutaneous Adverse Reactions (SCAR): Severe cutaneous adverse reactions, including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) have been reported with VOQUEZNA. Vitamin B12 (Cobalamin) Deficiency: Long-term use of acid-suppressing drugs can lead to malabsorption of Vitamin B12 caused by hypo- or achlorhydria. Vitamin B12 deficiency has been reported postmarketing with vonoprazan. Hypomagnesemia and Mineral Metabolism: Hypomagnesemia has been reported postmarketing with vonoprazan. Hypomagnesemia may lead to hypocalcemia and/or hypokalemia and may exacerbate underlying hypocalcemia in at-risk patients. Interactions with Diagnostic Investigations for Neuroendocrine Tumors: Serum chromogranin A (CgA) levels increase secondary to drug-induced decreases in gastric acidity. Fundic Gland Polyps: Use of VOQUEZNA is associated with a risk of fundic gland polyps that increases with long-term use, especially beyond one year. Healing of Erosive GERD: The most common adverse reactions (=2% of patients in the VOQUEZNA arm) include gastritis (3%), diarrhea (2%), abdominal distention (2%), abdominal pain (2%), and nausea (2%). Maintenance of Healed Erosive GERD: The most common adverse reactions (=3% of patients in the VOQUEZNA arm) include gastritis (6%), abdominal pain (4%), dyspepsia (4%), hypertension (3%), and urinary tract infection (3%). Relief of Heartburn Associated with Non-Erosive GERD: The most common adverse reactions (=2% of patients in the VOQUEZNA arm) include abdominal pain (2%), constipation (2%), diarrhea (2%), nausea (2%), and urinary tract infection (2%). Treatment of H. Pylori Infection (VOQUEZNA and Amoxicillin): The most common adverse reactions (=2% in any treatment arm) include diarrhea (5%), abdominal pain (3%), vulvovaginal candidiasis (2%), nasopharyngitis (2%), dysgeusia (1%), headache (1%), and hypertension (1%). Treatment of H. Pylori Infection (VOQUEZNA, Amoxicillin and Clarithromycin): The most common adverse reactions (=2% in any treatment arm) include dysgeusia (5%), diarrhea (4%), vulvovaginal candidiasis (3%), headache (3%), abdominal pain (2%), hypertension (2%), and nasopharyngitis (<1%). VOQUEZNA has the potential for clinically important drug interactions, including interactions with drugs dependent on gastric pH for absorption, drugs that are substrates for certain CYP enzymes, and some diagnostic tests. Avoid concomitant use of VOQUEZNA with atazanavir or nelfinavir. Pregnancy: There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to VOQUEZNA during pregnancy. Lactation: There are no data on the effects of vonoprazan on the breastfed child or the effects on milk production. Renal Impairment: For the healing of Erosive GERD, dosage reduction is recommended in patients with severe renal impairment (eGFR < 30 mL/min). Use of VOQUEZNA is not recommended for the treatment of H. pylori infection in patients with severe renal impairment. Hepatic Impairment: For the healing of Erosive GERD, dosage reduction is recommended in patients with moderate to severe hepatic impairment (Child-Pugh Class B and C). Use of VOQUEZNA is not recommended for the treatment of H. pylori infection in patients with moderate to severe hepatic impairment.
