Palleon Pharmaceuticals Presents Results from the Phase 1/2 GLIMMER-01 Trial of E-602 in Combination with Cemiplimab in Patients with Solid Tumors at the Society for Immunotherapy of Cancer (SITC) Annual Meeting

- Safety, proof of mechanism and early antitumor activity was demonstrated for E-602 in combination with cemiplimab in patients with PD-(L)1-resistant solid tumors

- E-602, a first-in-class human sialidase enzyme therapeutic developed from Palleon’s EAGLE platform is designed to restore antitumor immunity by degrading immunosuppressive sialoglycans on hypersialylated tumors and immune cells

WALTHAM, Mass.--(BUSINESS WIRE)--Palleon Pharmaceuticals, a clinical-stage company pioneering glyco-immunology drug development to treat autoimmune diseases and cancer, today announced results from the Phase 1/2 GLIMMER-01 trial of E-602, its first-in-class human sialidase enzyme therapeutic, in combination with PD-1 inhibitor cemiplimab (Libtayo^®) in patients with PD-(L)1-resistant solid tumors. The results will be shared in both rapid oral and poster presentations on Saturday, November 9 at the 2024 Society for Immunotherapy of Cancer (SITC) Annual Meeting in Houston, Texas.

In the Phase 1/2 study, 21 patients with anti-PD(L)-1-resistant melanoma, non-small cell lung cancer and esophagogastric junction cancer, defined according to the SITC consensus definition for resistance to immunotherapy, were treated with E-602 in combination with cemiplimab. All patients were assessed for tumor sialoglycan levels and characterized as having hypersialylation or not. The combination was generally well-tolerated, with no dose-limiting toxicities observed. Patients with tumor hypersialylation trended toward better clinical outcomes compared to those lacking hypersialylation, including a confirmed partial response achieved in one anti-PD-1 resistant melanoma patient, and disease stabilization achieved in another six patients. All patients lacking hypersialylation showed disease progression. In addition, paired tumor biopsies from patients with hypersialylation showed tumor desialylation and immune modulation in tumors, however, tumor desialylation only lasted 2-3 days with weekly dosing. These findings provide the first proof of mechanism for glycan editing as a novel therapeutic approach to modulating the immune system.

“The proof of mechanism and antitumor responses observed with E-602 as a combination therapy for patients with solid tumors further validate the therapeutic potential of targeting glyco-immunology to regulate the immune response in treating cancer and autoimmune diseases,” said Li Peng, Ph.D., Chief Scientific Officer of Palleon Pharmaceuticals. “We look forward to applying E-602 to treat diseases that align with its pharmacological characteristics, and advancing our next-generation EAGLE molecules that have a longer half-life sialidase and a tumor-targeting moiety to address the unmet needs of cancer patients.”

“E602 is the first candidate in a brand new class of therapeutics designed to modulate the immune system by targeting glyco-immunology. Palleon is building a rich pipeline of first-in-class drug candidates with the potential to improve and extend the lives of patients with diseases characterized by immune dysfunction, including cancer and autoimmunity,” added Jim Broderick, M.D., CEO and Founder of Palleon.

The study results will be available for viewing on the Palleon Publications section of the Education Hub page of Palleon’s website following the official presentation on November 9.

About Palleon Pharmaceuticals

Palleon Pharmaceuticals is the leading biotechnology company developing drugs that harness glyco-immunology to treat cancer and autoimmune diseases. The company’s proprietary platforms enable new target discovery, patient selection, and the development of novel therapeutics for devastating diseases characterized by immune system dysfunction. The groundbreaking discoveries of Palleon Co-Founder and Nobel laureate Carolyn Bertozzi enabled development of the company’s EAGLE glycan editing therapeutic platform. www.palleonpharma.com