Regeneron Pharmaceuticals will showcase new clinical data from its oncology pipeline at the European Society for Medical Oncology (ESMO) 2025 Meeting in Berlin, Germany, from October 17-21. The company announced seven abstracts highlighting advances in cancer treatment, with particular focus on new Phase 3 C-POST data demonstrating a patient-centric every 6-week dosing regimen for Libtayo® (cemiplimab) in high-risk cutaneous squamous cell carcinoma (CSCC).
C-POST Trial Demonstrates Flexible Dosing Options
The centerpiece of Regeneron's ESMO presentations involves new safety and pharmacokinetic data from the C-POST Phase 3 trial, which recently supported FDA approval of Libtayo as the first immunotherapy for adjuvant treatment of adult patients with CSCC at high risk of recurrence after surgery and radiation.
"Our oncology presentations at ESMO represent important progress toward expanding options for people with difficult-to-treat cancers," said Israel Lowy, M.D., Ph.D., Clinical Development Unit Head, Oncology, at Regeneron. "Notably, we look forward to sharing new data on a patient-centric every 6-week dosing option from our C-POST Phase 3 trial."
The C-POST trial design involved patients receiving either adjuvant therapy with Libtayo or placebo intravenously, starting with 350 mg every 3 weeks for 12 weeks. The majority of patients were then switched to every 6-week dosing after the initial 12 weeks, while remaining patients continued with dosing every 3 weeks throughout the trial. Treatment continued until disease recurrence, unacceptable toxicity, or up to 48 weeks of treatment.
According to the data being presented, efficacy, pharmacokinetics and immunogenicity were similar across both dosing regimens. The safety profile of Libtayo as adjuvant treatment of patients with CSCC at high risk of recurrence after surgery and radiation remained consistent with the known safety profile for Libtayo monotherapy in advanced cancers.
Comprehensive Oncology Portfolio Presentations
Beyond the C-POST data, Regeneron will present findings across multiple cancer types and investigational therapies. The presentations include analysis of second primary CSCC tumors reported during the C-POST trial, safety and effectiveness data from the CASE study in immunocompromised patients with advanced CSCC, and patient-reported outcomes data in advanced non-small cell lung cancer (NSCLC) patients treated with first-line cemiplimab-based therapy.
The company will also share data on ubamatamab, an investigational therapy being studied in a randomized Phase 2 trial for patients with platinum-resistant ovarian cancer, both as monotherapy and in combination with cemiplimab. Additionally, findings on REGN7075, an EGFRxCD28 bispecific antibody, will focus on mitigating infusion-related reactions using cetirizine and montelukast.
Strategic Focus on Difficult-to-Treat Cancers
Regeneron's oncology strategy centers on developing therapies for more than 30 types of solid tumors and blood cancers. The company's cancer portfolio is built on cutting-edge technologies including checkpoint inhibitors, bispecific antibodies, and costimulatory bispecific antibodies, with Libtayo serving as the backbone for many investigational combinations.
Oncology assets in clinical development comprise nearly half of Regeneron's pipeline, reflecting the company's commitment to transforming cancer care. The approved PD-1 inhibitor Libtayo has received regulatory approval in more than 30 countries for various indications, including advanced basal cell carcinoma, CSCC that is advanced or at high risk of recurrence, advanced NSCLC, and advanced cervical cancer.
Libtayo's Expanding Clinical Applications
Libtayo is a fully human monoclonal antibody targeting the immune checkpoint receptor PD-1 on T cells, developed using Regeneron's proprietary VelocImmune® technology. By binding to PD-1, Libtayo blocks cancer cells from using the PD-1 pathway to suppress T-cell activation.
The extensive clinical program for Libtayo focuses on difficult-to-treat cancers, with ongoing investigations as monotherapy and in combination with conventional or novel therapeutic approaches for various solid tumors and blood cancers. Current FDA-approved indications include treatment of adults with CSCC that has spread or cannot be cured by surgery or radiation, adjuvant treatment to help prevent CSCC recurrence in high-risk patients, advanced basal cell carcinoma, and various NSCLC scenarios both as monotherapy and in combination with platinum-containing chemotherapy.
