Immunome Announces Submission of New Drug Application to U.S. FDA for Varegacestat for the Treatment of Adults with Desmoid Tumors

• New Drug Application (NDA) supported by positive Phase 3 RINGSIDE results, including significant improvement in progression-free survival vs. placebo (hazard ratio = 0.16, p<0.0001)
• Trial also met all key secondary endpoints, with varegacestat delivering an objective response rate of 56%
• Detailed Phase 3 RINGSIDE data selected for oral presentation at the 2026 ASCO Annual Meeting

BOTHELL, Wash.--(BUSINESS WIRE)--Immunome, Inc. (Nasdaq: IMNM), a biotechnology company committed to developing first-in-class and best-in-class targeted cancer therapies, today announced the submission of a New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) for varegacestat, an investigational, oral, once-daily gamma secretase inhibitor (GSI), for the treatment of adults with desmoid tumors.

“The varegacestat NDA submission marks an important milestone for Immunome. It reflects the strength of the RINGSIDE dataset and the commitment of the team advancing this program,” said Clay B. Siegall, Ph.D., President and Chief Executive Officer of Immunome. “We believe varegacestat has the potential to provide adults with progressing desmoid tumors with a meaningful new oral treatment option, and we are grateful to the patients, families, investigators and study site teams whose participation made this submission possible.”

The NDA is supported by positive results from the global, randomized, double-blind, placebo-controlled Phase 3 RINGSIDE trial of varegacestat in patients with progressing desmoid tumors.

The trial met its primary endpoint of improving progression-free survival, demonstrating a statistically significant and clinically meaningful improvement vs. placebo, with an 84% reduction in the risk of disease progression or death (hazard ratio (HR) = 0.16, 95% CI: 0.071, 0.375; p<0.0001). The confirmed objective response rate (ORR) based on RECIST v1.1 was 56% with varegacestat vs. 9% with placebo (p<0.0001), as assessed by blinded independent central review.

In an exploratory analysis, varegacestat demonstrated a median best change in tumor volume of -83% vs. +11% with placebo, as assessed by blinded independent central review. In addition, the trial met all key secondary endpoints, with varegacestat achieving statistically significant improvements vs. placebo in landmark tumor volume reduction and worst pain intensity.

Varegacestat was generally well tolerated, with a manageable safety profile consistent with the GSI class. The most common adverse events for participants in the treatment arm were diarrhea (82%), fatigue (44%), rash (43%), nausea (35%) and cough (34%). Most events were grade 1 or 2.

Immunome previously announced that data from RINGSIDE has been selected for presentation in an oral abstract session at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting, taking place May 29-June 2, 2026 in Chicago.

About the RINGSIDE Trial

The global, randomized, double-blind, placebo-controlled Phase 3 RINGSIDE trial (NCT04871282) evaluated the efficacy and safety of varegacestat in patients with progressing desmoid tumors. A total of 156 patients were randomized to receive varegacestat 1.2 mg daily or placebo until disease progression or death, representing the largest randomized study in this population. The primary endpoint of the trial was progression-free survival as assessed by blinded independent central review. Statistically controlled secondary endpoints were confirmed ORR using RECIST v1.1 and change in tumor volume at week 24, both determined by blinded independent central review, as well as change in pain intensity at week 12 as determined using a patient reported outcome instrument. Additional secondary endpoints included duration of response, best reduction in tumor volume, patient-reported outcomes, and safety and tolerability. RINGSIDE includes an open-label extension phase, which is ongoing.

About Desmoid Tumors

Desmoid tumors (also known as aggressive fibromatosis or desmoid-type fibromatosis) are aggressive non-metastatic soft tissue tumors that are prone to recurrence. Approximately 1,000-1,650 people are diagnosed with desmoid tumors each year in the United States, and there are approximately 10,000-11,000 actively managed patients. Those affected face debilitating pain, deformity and, in some cases, life-threatening organ damage. The chronic pain and physical limitations associated with desmoid tumors lead to a high clinical burden and impaired quality of life. Although desmoid tumors are not considered cancerous, they often require systemic treatment to prevent permanent disability and alleviate disease burden.

About Varegacestat

Varegacestat (formerly AL102) is an investigational, oral, once-daily gamma secretase inhibitor. In December 2025, Immunome reported positive topline results for the Phase 3 RINGSIDE trial of varegacestat in adults with progressing desmoid tumors. Data from RINGSIDE have been selected for oral presentation at the 2026 ASCO Annual Meeting.

About Immunome, Inc.

Immunome is a clinical-stage targeted oncology company committed to developing first-in-class and best-in-class targeted cancer therapies. We are advancing an innovative portfolio of therapeutics, drawing on leadership that previously played key roles in the design, development, and commercialization of cutting-edge therapies, including antibody-drug conjugate therapies. Our pipeline includes varegacestat, a late-clinical stage GSI; IM-1021, a clinical-stage ROR1 ADC; and IM-3050, a FAP-targeted radiotherapy that recently received IND clearance. We are also advancing a broad portfolio of early-stage ADCs pursuing undisclosed solid tumor targets. For more information, visit www.immunome.com

Cautionary Statement Regarding Forward-Looking Statements

Statements in this press release that are not purely historical in nature are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. We use words such as “commitment,” “advancing,” “believe,” “potential,” and similar expressions to identify these forward-looking statements. These forward-looking statements include statements regarding the potential of varegacestat, including its therapeutic benefits, its ability to provide a meaningful new oral treatment option and regulatory outcomes; Immunome’s plans to provide additional data from the RINGSIDE trial; the continued advancement of varegacestat; and other statements regarding management’s intentions, plans, beliefs, expectations or forecasts for the future.

These forward-looking statements are based on Immunome’s current expectations and involve assumptions that may never materialize or may prove to be incorrect; consequently, actual results may differ materially from those expressed or implied due to a number of factors, including risks related to the NDA submission for varegacestat, such as potential delays or failure to obtain regulatory approval; risks related to the safety profile of varegacestat; risks related to the labeling and commercialization of varegacestat, if approved; Immunome’s ability to grow and advance its pipeline and execute on its business plan; and other risks and uncertainties included under the caption “Risk Factors” in Immunome’s Annual Report on Form 10-K for the year ended December 31, 2025, filed with the Securities and Exchange Commission on March 3, 2026.

These documents can also be accessed on Immunome’s website at www.immunome.com by clicking on the link “Financials” under the “Investors” tab. The forward-looking statements included in this press release are made only as of the date of this press release. Except as required by law, Immunome assumes no obligation and does not intend to update any forward-looking statements included in this press release.