Phase 1 clinical trial of novel agent misetionamide (GP-2250), an inhibitor of

c-MYC and NF?B, is nearly complete

Interim analysis shows misetionamide is very well tolerated in combination with gemcitabine; rates of confirmed response, stable disease, and progression-free survival compare favorably with gemcitabine monotherapy

BERWYN, PA - Panavance Therapeutics Inc. [https://panavance.com/] ("Panavance" or the "Company"), a clinical-stage pharmaceutical company advancing the development of a novel oncology therapeutic intended to improve the outcomes and quality of life for patients, today presented promising interim findings at the American Society of Clinical Oncology (ASCO) 2025 Annual Meeting, held May 30-June 3, 2025, in Chicago, Illinois.

The poster presentation shared the encouraging findings of the nearly complete Phase 1 dose escalation clinical trial [https://clinicaltrials.gov/study/NCT03854110] of the novel agent misetionamide (GP-2250), an inhibitor of c-MYC and NF?B, two major oncogenic transcription factors, as well as an antiangiogenic transcription factor, HIF1?, as second-line therapy in combination with gemcitabine. To date, 55 patients with advanced/metastatic pancreatic cancer have enrolled across seven US sites.

The combination of misetionamide and gemcitabine has been very well tolerated, with no new or exacerbated toxicities evident compared with those expected of gemcitabine alone.

Anup Kasi, MD, MPH, Associate Professor, Medical Oncology, at the University of Kansas Cancer Center and lead investigator of the ongoing Phase 1 clinical trial, presented the latest trial update in a poster at ASCO. "The combination of misetionamide and gemcitabine has shown promising synergistic activity, with around 42% of patients experiencing either a partial response or stable disease," said Dr. Kasi. "The extent of tumor regression observed with this combination appears to compare favorably with historical outcomes from gemcitabine alone. These interim results-highlighting both early efficacy and a favorable safety and tolerability profile-suggest the combination of misetionamide plus gemcitabine may offer a meaningful new treatment option for patients with pancreatic cancer."

Based on the trial results along with the therapeutic's novel mechanism of action and broad spectrum of activity across 13 xenograft models, further clinical trials with misetionamide are warranted.

"These very promising preliminary results bring us another step closer to providing transformative therapies for patients with pancreatic cancer, which has historically been difficult to treat," said Greg Bosch [https://panavance.com/leadership/], Chairman and CEO of Panavance.

The poster, "Interim Open-Label Phase 1 Results of Misetionamide (GP-2250): A Small Molecule Antineoplastic That Inhibits Three Major Transcription Factors [https://panavance.com/wp-content/uploads/2025/05/asco-2025-kasi-et-al-interim-open-label-phase-1-results-of-misetionamide-gp-2250.pdf]," was presented by Dr. Kasi on Saturday, May 31, 2025.

About Panavance Therapeutics

Panavance Therapeutics is a privately held, clinical-stage pharmaceutical company developing a novel oncology asset, misetionamide (also known as GP-2250). Panavance, a US Delaware company based in Berwyn, PA, was founded in 2021 as a wholly owned carve out of the Geistlich group, a family-owned Swiss company, to focus on misetionamide and the oncology business.

Misetionamide is a broadly active small molecule with a novel mechanism of action that inhibits two oncogenic transcription factors, c-MYC and NF?B. Acting through c-MYC, misetionamide selectively disrupts the energy metabolism of cancer cells leading to cancer cell death. Through NF?B inhibition, misetionamide inhibits cancer cells' ability to proliferate and survive. This dual-target mechanism makes misetionamide an attractive tumor cell selective agent.

Panavance is currently conducting a multicenter, Phase 1 dose escalation trial in four US clinical sites. The Company plans to initiate a clinical trial of misetionamide for the treatment of platinum-resistant ovarian cancer and a clinical trial as a first-line maintenance therapy for non-BRCA mutated pancreatic cancer patients, a population for which there are no FDA approved drugs. Extensive preclinical studies have demonstrated that misetionamide's broadly antineoplastic MOA has the potential to be effective in additional tumor types, including melanoma, squamous cell, breast, and colorectal cancers.

For more information, please visit panavance.com [https://panavance.com/] and connect with the Company on Twitter [https://x.com/panavance], LinkedIn [https://www.linkedin.com/company/panavance-therapeutics/], and Facebook [https://www.facebook.com/PanavanceCancerClinicalTrial].

Media Contact

Carol Gorman

Panavance Therapeutics

(610) 922-1910

ContactUS@panavance.com