The primary end point was ORR by blinded independent central review per RECIST 1.1 in arm 1, which was compared with an assumed historic control ORR of 10%. Secondary end points were ORR in arms 2 and 3, duration of response, DCR, time to response, PFS, OS, safety, tolerability, and patient-reported outcomes.
Patients were followed for safety for 90 days and OS every 3 months for up to 48 months from the last randomization.
What Were the Baseline Characteristics of the Trial Population?
Baseline characteristics of the combination arm revealed that the median age was 64.0 (range, 18-84) and most patients were male (63.8%) and had an ECOG performance status of 0 (78.7%). The majority also had stage IV disease at baseline (97.9%), M1c disease (44.7%), and between 2 and 5 prior therapies (56.4%). Patients also were PD-(L)1 refractory (56.4%), and had liver metastases (25.5%), BRAF V600 mutations (28.7%), prior BRAF/MEK therapy (18.1%), and prior ipilimumab (48.9%).
“All patients were PD-(L)1 relapsed/refractory and had received one or multiple prior therapies with half of patients being CTLA4 pretreated,” Ascierto said.
How Did the Regimen Compare With Each Agent Alone?
“BNT111 also indicated clinical activity as monotherapy.” The ORR was 17.4% (95% CI, 7.8%-31.4%) with BNT111 monotherapy (n = 46), which included best responses of CR (13.0%), PR (4.3%), and SD (41.3%). The DCR was 58.7% (95% CI, 43.2%-73.0%). With cemiplimab monotherapy (n = 44), the ORR was 13.6% (95% CI, 5.2%-27.4%), with best responses of CR (4.5%), PR (9.1%), and SD (34.1%). The DCR was 47.7% (95% CI, 32.5%-63.3%).
Median follow-up was 11.8 months (range, 0.6-38.4) in the BNT111 arm and 16.9 months (range, 1.9-39.5) in the cemiplimab arm. In the BNT111 monotherapy arm, the median PFS was 2.8 months (95% CI, 2.6-4.7); the 24-month PFS rate was 20.9% (95% CI, 8.0%-37.9%). The median OS was 13.7 months (95% CI, 10.2-24.6); the 24-month OS rate was 37.6% (95% CI, 22.7%-52.5%). In the cemiplimab monotherapy arm, the median PFS was 3.2 months (95% CI, 1.5-5.0); the 24-month PFS rate was 10.6% (95% CI, 1.1%-32.5%). The median OS was 22.3 months (95% CI, 14.6-33.2); the 24-month OS rate was 43.1% (95% CI, 26.5%-58.7%).
What Was the Safety Profile of the Combination?
With respect to safety in the combination arm (n = 92) treatment-emergent adverse effects (TEAEs) associated with cytokine release included pyrexia (any grade, 76.1%; grade ≥3, 0%), hypertension (any grade, 12.0%; grade ≥3, 6.5%), hypotension (any grade, 13.0%; grade ≥3, 2.2%), fatigue (any grade, 25.0%; grade ≥3, 3.3%), cytokine release syndrome (any grade, 8.7%; grade ≥3, 1.1%), and chills (any grade, 51.1%; grade ≥3, 0%).
TEAEs leading to dose reduction (9.8%), interruption (29.3%), and discontinuation (6.5%) also occurred. TEAEs occurred in 98.9% of cases and were deemed related to BNT111 in 97.8% (grade ≥3, 18.5%) and cemiplimab in 71.7% (grade ≥3, 14.1%).
“BNT111, both as a monotherapy and in combination therapy, exhibited a manageable safety profile, which is primarily driven by the induction of cytokines through toll-like receptors by the single-stranded RNA immunotherapy,” Ascierto said in conclusion.
Disclosures: Ascierto disclosed serving as a consultant or advisory role for Bristol-Myers Squibb, Roche-Genentech, Merck Sharp & Dohme, Novartis, Merck Serono, Pierre-Fabre, Sun Pharma, Immunocore, Italfarmaco, Boehringer-Ingelheim, Regenerson, Pfizer, Nouscom, Lunaphore, Medicenna, Bio-Al Health, ValoTx, Replimune, Bayer, Erasca, Philogen, BioNTech, Anaveon, Genmab, Menarini, Incyte, and ImCheck Therapeutics; research funding from Bristol-Myers Squibb, Roche-Genentech, Pfizer, Regeneron, and Medicenna; travel support from Pfizer, Bio-Al Health, Replimune, MSD, Pierre Fabre, and Philogen; and non-financial interests as president of the Fondazione Melanoma Onlus, president of the Campania Society of ImmunoTherapy of Cancer, member of the steering committee of the Society of Melanoma Research, and a member of the Board of Directors for the Society of Immuno-Therapy of Cancer.
References
- Ascierto PA, Grabbe S, Guida M, et al. Primary results from a randomized phase II trial of BNT111 in combination with cemiplimab with calibrator monotherapy arms in anti-PD-(L)1 relapsed/refractory melanoma. Presented at: 2025 ESMO Congress; October 17-21, 2025; Berlin, Germany. Abstract 1605MO.
- BioNTech announces positive topline phase 2 results for mRNA immunotherapy candidate BNT111 in patients with advanced melanoma. News release. BioNTech SE. July 30, 2024. Accessed October 18, 2025. https://investors.biontech.de/news-releases/news-release-details/biontech-announces-positive-topline-phase-2-results-mrna
- BioNTech receives FDA fast track designation for its FixVac candidate BNT111 in advanced melanoma. News release. BioNTech SE. November 19, 2021. Accessed October 18, 2025. https://investors.biontech.de/news-releases/news-release-details/biontech-receives-fda-fast-track-designation-its-fixvac