1783P - PROSTRATEGY: A SOGUG randomized trial of androgen deprivation therapy (ADT) plus docetaxel (dct) +/- nivolumab (nivo) or ipilimumab-nivolumab (ipi-nivo) in high-volume metastatic hormone-sensitive prostate cancer (hvHSPCa) - Efficacy results from the pilot phase

Background

ADT+ dct has been a standard of care first-line for hvHSPC patients (pt). We hypothesized that early addition of ipi and/or nivo could improve outcomes.

Methods

PROSTRATEGY was designed as a seamless randomized (2/1/1) multi-arm multi-stage trial, to compare ADT+dct (75 mg/m² x6 cycles) vs ADT+dct→nivo (3 mg/Kg/2w x 12 mo), or ADT+ipi+dct→nivo (ADT + ipi 1 mg/Kg/3w x 2 cycles → dct x3 cycles → ipi 3mg/Kg/3w x2 cycles → dct x3 cycles → nivo x 12 mo) in hvHSPCa pt in 30 academic centers in Spain. The aims of the pilot phase were to check ffeasibility, safety and efficacy outcomes in terms of radiographic and PSA response, radiographic and clinical progression-free survival or death (rPFS, cPFS), time to castration-resistant prostate cancer or death (TCRPC), time to symptomatic skeletal-related event (TSSRE) and overall survival (OS) from the first dose of ADT, based on both RECIST1.1 + PCWG3 and iRECIST ( Seymour, Lancet Oncol 2017 ) + PCWG3 criteria.

Results

150 pt were randomized to dct (75 pt), dct-nivo (37 pt) or dct+ipi-nivo (38 pt). Mean age was 66.4 y (39% >70 y), 98% were Caucasian, 99.3% had ECOG 0-1, 88% were metastatic at diagnosis, mean PSA was 157 ng/ml, 88% had Gleason ≥ 8, 31% visceral involvement, and 17% received local therapy to the prostate, with no differences among arms. With a median follow-up of 32.5 mo from ADT, 60% of pt have progressed and 41.3% have died. Safety is described separately. Efficacy results are summarized in the table. Table: 1783P

Conclusions

The addition of ipi and/or nivo to ADT + Dct in pt with hvHSPCa is feasible. So far, we have found no statistical or clinically meaningful differences between arms that justify the continuation of the study. Results seem to be similar regardless of using PCWG3 plus either RECIST or iRECIST criteria although some differences between both methods may appear with longer follow-up.

Clinical trial identification

EudraCT 2017-004377-13.

Editorial acknowledgement

Legal entity responsible for the study

SOGUG (Spanish Genitourynary Oncology Group).

Funding

BMS.

Disclosure

J.A. Arranz Arija: Non-Financial Interests, Institutional, Funding, SOGUG: BMS; Financial Interests, Personal, Advisory Board: BMS, Astellas, Pfizer, Novartis, Bayer, AstraZeneca, Ipsen, EUSA; Financial Interests, Personal, Invited Speaker: Merck. J.M. Piulats Rodriguez: Financial Interests, Personal, Advisory Board: Janssen, Astellas, Roche, BMS, MSD, BeiGene, VCN, AstraZeneca; Financial Interests, Personal and Institutional, Research Grant: BMS, Pfizer, Janssen, BeiGene, Mirati. T. Alonso Gordoa: Financial Interests, Personal, Advisory Board: Ipsen, Pfizer, Roche, Sanofi, Bayer, Eisai, Novartis Advanced Accelerator Applications, Lilly, BMS, Astellas; Financial Interests, Personal, Invited Speaker: Janssen Cilag; Non-Financial Interests, Project Lead: Pfizer, Ipsen. B. Perez Valderrama: Financial Interests, Personal, Advisory Board: Pfizer, Astellas Pharma, BMS, Ipsen, EUSA Pharma, Merck, MSD, AstraZeneca, AAA; Financial Interests, Personal, Invited Speaker: BMS, Roche, Bayer, EUSA Pharma, MSD, Merck, Pfizer, Janssen, Astellas Pharma, AAA. N. Sala González: Financial Interests, Personal, Advisory Board: BMS, Merck, Pfizer; Financial Interests, Personal, Invited Speaker: Ipsen. M.A. Climent Duran: Financial Interests, Personal, Advisory Board: Roche, BMS, EUSA, Pfizer, Sanofi, Janssen, Astellas, Merck, Ipsen, MSD; Financial Interests, Personal, Invited Speaker: EUSA, Pfizer, Sanofi, Janssen, Astellas, Merck, Ipsen, BMS, Roche, MSD. E. Gallardo Diaz: Financial Interests, Personal, Advisory Board: Sanofi, Janssen, Astellas, Pfizer, Bayer, Roche, Ipsen, Eisai, EUSA Pharma, BMS, AstraZeneca, Merck, Daiichi Sankyo, Techdow, Lilly, Advanced Accelerator Applications, GSK; Financial Interests, Personal, Invited Speaker: Sanofi, Janssen, Astellas, Pfizer, Bayer, Roche, Ipsen, Eisai, EUSA Pharma, BMS, Merck, Daiichi Sankyo, MSD, Menarini, Rovi, Leo Pharma, Boehringer Ingelheim, Advanced Accelerator Applications; Financial Interests, Personal, Expert Testimony: Merck, Novartis, Pfizer; Financial Interests, Institutional, Local PI: Astellas, Medivation, Ipsen, Janssen, Pfizer, Lilly, Pfizer-Merck, MSD, BMS, Bayer, Daiichi Sankyo, Roche, AstraZeneca, Novartis, Seattle Genetics, Incyte, Aveo, Exelixis, Immunicum, Mediolanum, Clovis, QED Therapeutics; Non-Financial Interests, Leadership Role, Member of the Board: SOGUG; Non-Financial Interests, Leadership Role, Member of the Board of Thrombosis and Cancer Section: SEOM. A. Rodriguez-Vida: Financial Interests, Personal, Invited Speaker: Roche, BMS, Janssen, AstraZeneca, Ipsen; Financial Interests, Personal, Advisory Board: MSD, Pfizer, Astellas, Bayer, Merck. C. Caballero Diaz: Financial Interests, Personal, Advisory Board: Astellas, Ipsen, Ipsen, Janssen, Pfizer, GSK, GSK, BMS, AstraZeneca; Financial Interests, Personal, Invited Speaker: Astellas, Ipsen, Janssen, Pfizer, Roche, Sanofi, BMS, AstraZeneca. J. Puente: Financial Interests, Personal, Advisory Board: Astellas, AstraZeneca, Janssen, MSD, Pfizer, Eisai, Ipsen, Roche, BMS, Merck; Financial Interests, Personal, Invited Speaker: Astellas, AstraZeneca, Janssen, MSD, Bayer, Pfizer, Eisai, Roche, BMS, Merck; Financial Interests, Institutional, Research Grant: Astellas, Roche, Merck. M.J. Mendez Vidal: Financial Interests, Personal, Advisory Board: BMS, MSD, Novartis, Ipsen, Astellas, Pfizer, Merck, Sanofi, Eisai, Bayer; Financial Interests, Personal, Invited Speaker: BMS, Ipsen, Roche, Astellas, Merck, Bayer; Non-Financial Interests, Other, Travel expenses: Ipsen, BMS. E.M.F. Parra: Financial Interests, Personal, Invited Speaker: Bayer, BMS, Merck; Financial Interests, Personal, Advisory Board: Ipsen. J. García Sanchez: Financial Interests, Personal, Advisory Board: Sanofi, Pfizer, Eisai; Financial Interests, Personal, Invited Speaker: Merck, Takeda, PharmaMar, BMS, Novartis. J. Carles Galceran: Financial Interests, Personal, Advisory Board: Astellas Pharma, AstraZeneca, Bayer, Johnson & Johnson, MSD Oncology, Novartis (AAA), Roche, Sanofi; Financial Interests, Institutional, Local PI: Janssen Cilag International NV, Lilly, S.A, Medimmune, Novartis Farmacéutica, S.A, Sanofi-Aventis, S.A. All other authors have declared no conflicts of interest.