Phathom starts Phase 3 trial: Phathom Pharmaceuticals stock faces 2028 results

Published on 10/01/2026 at 09:35 | Editorial responsibility: Rafael Müller, Editor-in-Chief AD HOC NEWS

The study targets 500 patients at 80 U.S. sites. Phathom Pharmaceuticals stock has a USD 590.6 million market value as of September 30, 2026.

PHAT, US71738P1066, Illustration mit AI erstellt.

Phathom Pharmaceuticals (US71738P1066) began screening patients for the Phase 3 pHalcon-NERD-302 study on September 29, 2026. The trial tests as-needed VOQUEZNA, or vonoprazan, in adults with non-erosive gastroesophageal reflux disease, with topline results expected in the first quarter of 2028, according to GlobeNewswire.

500 patients and a 2028 readout

Phathom plans to enroll 500 adults who experience heartburn at least four days per week. The study is planned for 80 U.S. sites, with patients receiving either VOQUEZNA 10 mg or placebo as needed during a 24-week treatment period.

The primary endpoint is assessed at Week 12 and measures complete relief within two hours that remains sustained for 24 hours after dosing. A successful result could support a regulatory submission to expand VOQUEZNA's label for as-needed treatment, although the company identifies enrollment, trial execution, safety, and regulatory review as material risks in the September 29, 2026 release.

Revenue growth narrows the loss

Phathom's commercial base expanded in the second quarter of 2026. Revenue reached USD 74.27 million, up from USD 39.50 million in the second quarter of 2025, while the GAAP net loss narrowed to USD 17.58 million from USD 75.81 million, according to Markets Insider on September 21, 2026.

The revenue comparison shows the commercial leverage investors are watching, while the smaller loss points to lower cash pressure than in the prior-year quarter. Phathom markets VOQUEZNA for several gastrointestinal indications and is extending development into as-needed non-erosive GERD and eosinophilic esophagitis, according to the company's investor-relations page.

Market value and Nasdaq listing

Phathom Pharmaceuticals had a market capitalization of USD 590.6 million as of September 30, 2026. Its 52-week range was USD 6.91 to USD 18.31, putting the market value and development timeline in the context of a stock that remains well below its yearly high.

The company is listed on Nasdaq under ticker PHAT, as identified in the September 29, 2026 company release. The investor-relations page describes Phathom as a biotechnology company focused on gastrointestinal diseases and identifies vonoprazan as its leading commercial and development asset.

Stock context for investors

At the latest dated primary-market snapshot, Phathom Pharmaceuticals stock stood at USD 7.30 on September 30, 2026, with a daily change of minus 0.82 percent versus USD 7.36. The new Phase 3 program supplies a concrete development milestone, but its expected first-quarter 2028 readout leaves a long period before investors receive efficacy data.