Neoantigens arise from DNA mutations in cancer cells and are important targets for T cells. Adjuvant therapy with a personal neoantigen vaccine induced T cell responses in melanoma (mel) patients and suggested synergy with anti-PD1 mAbs (Ott et al, Nature 2017). NEO-PV-01 is a personal neoantigen vaccine of up to 20 peptides (14-35 amino acids) designed based on bioinformatic analysis of a patient’s neoantigen and HLA profile. We report clinical and immune data of NEO-PV-01 in combination with nivolumab (nivo) in metastatic cancer.
NT-001 is a single-arm, phase 1b study of NEO-PV-01 with nivo in advanced mel, NSCLC, or bladder cancer. Patients begin nivo at Week 0 and at Week 12 receive NEO-PV-01 vaccine plus adjuvant Poly-ICLC in a prime-boost format. The primary endpoint is safety; secondary endpoints include overall response rate (ORR) and response conversion rate. Comprehensive immune assessments are performed throughout with biopsies at Weeks 0, 12 and 24.
31 patients received at least one vaccination by the data cut and 19 had completed the full vaccine course. Vaccine-related AEs were mild (e.g., grade 1/2 injection site reactions and flu-like symptoms), with no vaccine-related SAEs. For post vaccination patients, the ORR was 52.6% (n = 10), with 2 mel and 1 NSCLC patient having response conversions. 13 patients remain on treatment (11 mel, 1 NSCLC, 1 bladder). Immune analysis was completed on 9 patients (including all 3 tumor types). Ex vivo neoantigen-specific CD4 and CD8 T cell responses against >60% of vaccine peptides were polyfunctional and of a memory phenotype. Epitope spreading post-vaccination (T cell responses to neoantigens not in the vaccine but in the patient’s tumor) was observed in 4 of 6 patients analyzed. In a subset of patients, pathologic review of pre- vs post-vaccine biopsies showed decreased tumor cellularity following vaccination.
Treatment with NEO-PV-01 and nivo has minimal toxicity and promising clinical activity. NEO-PV-01 is effective in inducing broad de novo neoantigen-specific immune responses in patients with metastatic cancers.
Clinical trial identification
Legal entity responsible for the study
Neon Therapeutics, Inc.
Neon Therapeutics, Inc.
P.A. Ott: Consulting: Neon, BMS, Merck, Novartis, Pfizer, Roche/Genentech, Celldex, CytomX. R. Govindan: Consulting and honorarium: Genentech; Advisory board: Genentech, Pfizer, Nektar, Inivata, NeoHealth, BMS. A. Naing: Research funding: NCI, EMD Serono, MedImmune, Healios Onc. Nutrition, Atterocor, Amplimmune, Armo Biosciences, Karyopharm Therapeutics, Incyte, Novartis, Regeneron, Baxter (spouse). T.W. Friedlander: Advisory board: Genetech, Pfizer, AstraZeneca; Research funding: Novartis, Incyte, Janssen. J.J. Lin: Honorarium: Chugai, Boehringer-Ingelheim. N. Bhardwaj: Advisory board: Neon Therapeutics, Inc. M.D. Hellman: Advisory board: Genentech/Roche, BMS, AstraZeneca, Merck, Janssen, Norvartis, Mirati, Shattuck Labs; Research support: BMS. L. Srinivasan, J. Greshock, M. Moles, R.B. Gaynor, M.J. Goldstein: Employee: Neon Therapeutics, Inc. S. Hu-Lieskovan: Consulting: Amgen, Merck, Genmab, Xencor; Research support: BMS, Merck, Vaccinex. All other authors have declared no conflicts of interest.