A.M. Menzies, B.A. van de Wiel, J.B.A.G. Haanen, Judith M. Versluis, Ron M. Kerkhoven, Acj van Akkooi, Christian U. Blank, Elisa A. Rozeman, Carolien Bierman, Ilm Reijers, W.J. van Houdt, Georgina V. Long, Oscar Krijgsman, Annegien Broeks, Hanna Eriksson, Richard A. Scolyer, Andrew J. Spillane, T.N. Schumacher, Rpm Saw, Petros Dimitriadis, Karolina Sikorska, María Jesús González González, and Esmée P. Hoefsmit
Background Before adjuvant checkpoint inhibition the 5-year overall survival (OS) rate was poor ( Materials and Methods The phase 1b OpACIN trial included 20 stage IIIB/IIIC melanoma patients, which were randomized to receive IPI 3 mg/kg plus NIVO 1 mg/kg either adjuvant 4 cycles or split 2 cycles neoadjuvant and 2 adjuvant. In the phase 2 OpACIN-neo trial, 86 patients were randomized to 2 cycles neoadjuvant treatment, either in arm A: 2x IPI 3 mg/kg plus NIVO 1 mg/kg q3w (n=30), arm B: 2x IPI 1 mg/kg plus NIVO 3 mg/kg q3w (n=30), or arm C: 2x IPI 3 mg/kg q3w followed immediately by 2x NIVO 3 mg/kg q3w (n=26). Pathologic response was defined as Results Only 1 of 71 (1.4%) patients with a pathologic response on neoadjuvant therapy had relapsed, versus 16 of 23 patients (69.6%) without a pathologic response, after a median follow-up of 36 months for the OpACIN and 24 months for the OpACIN-neo trial. In the OpACIN trial, the estimated 3-year RFS rate for the neoadjuvant arm was 80% (95% CI: 59%-100%) versus 60% (95% CI: 36%-100%) for the adjuvant arm. Median RFS was not reached for any of the arms within the OpACIN-neo trial. Estimated 24-months RFS rate was 84% for all patients (95% CI: 76%-92%); 90% for arm A (95% CI: 80%-100%), 78% for arm B (95% CI: 63%-96%) and 83% for arm C (95% CI: 70%-100%). Baseline interferon-γ gene expression score and tumor mutational burden predict response. Conclusions OpACIN for the first time showed a potential benefit of neoadjuvant IPI plus NIVO versus adjuvant immunotherapy, whereas the OpACIN-neo trial confirmed the high pathologic response rates that can be achieved by neoadjuvant IPI plus NIVO. Both trials show that pathologic response can function as a surrogate markers for RFS. Clinical trial information NCT02437279, NCT02977052 Disclosure Information J.M. Versluis: None. E.A. Rozeman: None. A.M. Menzies: F. Consultant/Advisory Board; Modest; BMS, MSD, Novartis, Roche, Pierre-Fabre. I.L.M. Reijers: None. O. Krijgsman: B. Research Grant (principal investigator, collaborator or consultant and pending grants as well as grants already received); Modest; BMS. E.P. Hoefsmit: None. B.A. van de Wiel: None. K. Sikorska: None. C. Bierman: None. P. Dimitriadis: None. M. Gonzalez: None. A. Broeks: None. R.M. Kerkhoven: None. A.J. Spillane: None. J.B.A.G. Haanen: B. Research Grant (principal investigator, collaborator or consultant and pending grants as well as grants already received); Modest; BMS, MSD, Neon Therapeutics, Novartis. F. Consultant/Advisory Board; Modest; BMS, MSD, Novartis, Pfizer, AZ/MedImmune, Rocher/Genentech, Ipsen, Bayer, Immunocore, SeattleGenetics, Neon Therapeutics, Celsius Therapeutics, Gadet, GSK. W.J. van Houdt: None. R.P.M. Saw: None. H. Eriksson: None. A.C.J. van Akkooi: B. Research Grant (principal investigator, collaborator or consultant and pending grants as well as grants already received); Modest; Amgen, BMS, Novartis. F. Consultant/Advisory Board; Modest; Amgen, BMS, Novartis, MSD Merck, Merck-Pfizer, 4SC. R.A. Scolyer: F. Consultant/Advisory Board; Modest; MSD, Neracare, Myriad, Novartis. T.N. Schumacher: B. Research Grant (principal investigator, collaborator or consultant and pending grants as well as grants already received); Modest; MSD, BMS, Merck. E. Ownership Interest (stock, stock options, patent or other intellectual property); Modest; AIMM Therapeutics, Allogene Therapeutics, Amgen, Merus, Neogene Therapeutics, Neon Therapeutics. F. Consultant/Advisory Board; Modest; Adaptive Biotechnologies, AIMM Therapeutics, Allogene Therapeutics, Amgen, Merus, Neon Therapeutics, Scenic Biotech. Other; Modest; Third Rock Ventures. G.V. Long: F. Consultant/Advisory Board; Modest; Aduro, Amgen, BMS, Mass-Array, Pierre-Fabre, Novartis, Merck MSD, Roche. C.U. Blank: B. Research Grant (principal investigator, collaborator or consultant and pending grants as well as grants already received); Modest; BMS, Novartis, NanoString. E. Ownership Interest (stock, stock options, patent or other intellectual property); Modest; Uniti Cars, Neon Therapeutics, Forty Seven. F. Consultant/Advisory Board; Modest; BMS, MSD, Roche, Novartis, GSK, AZ, Pfizer, Lilly, GenMab, Pierre-Fabre.