774P - STRIDE, a randomized, phase 2, open-label study of sipuleucel-T with concurrent vs sequential enzalutamide in metastatic castration-resistant prost...

Date 27 September 2014
Event ESMO 2014
Session Poster Display session
Topics Anti-Cancer Agents & Biologic Therapy
Prostate Cancer
Cancer Immunology and Immunotherapy
Presenter Daniel Petrylak
Citation Annals of Oncology (2014) 25 (suppl_4): iv255-iv279. 10.1093/annonc/mdu336
Authors D.P. Petrylak1, D.I. Quinn2, R. Dreicer3, E.S. Antonarakis4, N.D. Shore5, J. Corman6, R. Concepcion7, C.M. Pieczonka8, A. Stubbs9, N. Sheikh10, T. Devries11, A. Sandler12, C. Drake13
  • 1Genitourinary Oncology Research Program, Yale Cancer Center, 06520 - New Haven/US
  • 2Norris Comprehensive Cancer Center, University of Southern California Norris Comprehensive Cancer Center, 90033 - Los Angeles/US
  • 3Oncology, Cleveland Clinic, 44195 - Cleveland/US
  • 4Oncology, Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, 21287 - Baltimore/US
  • 5Urology, Carolina Urologic Research Center, Myrtle Beach/US
  • 6Surgery, Virginia Mason Medical Center, 98111 - Seattle/US
  • 7Urology, Urology Associates, 37209 - Nashville/US
  • 8Urology, Associated Medical Professionals of New York, 13210 - Syracuse/US
  • 9Medical Affairs, Dendreon, 92101 - Seattle/US
  • 10Clinical Immunology, Dendreon Corporation, Seattle/US
  • 11Biometrics, Dendreon, 92101 - Seattle/US
  • 12Medical Affairs, Dendreon Corporation, 98101 - Seattle/US
  • 13Department Of Urology, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins University, Baltimore/US

Abstract

Aim

Multiple treatment options exist for patients (pts) with mCRPC, particularly in the setting of early metastasis. Sipuleucel-T, an autologous cellular immunotherapy, and enzalutamide, an androgen receptor inhibitor, are approved in the US and EU for treatment of mCRPC, but data are limited regarding use of these agents in combination. P12-2 (STRIDE; NCT01981122) is an ongoing, randomized, open-label, phase 2 study designed to evaluate concurrent vs sequential administration of sipuleucel-T and enzalutamide.

Methods

Pts with asymptomatic or minimally symptomatic mCRPC are randomized 1:1 to receive sipuleucel-T with enzalutamide (160 mg QD for 52 wk) starting 2 wk before (concurrent arm [A]) or 10 wk after (sequential arm [B]) initiation of sipuleucel-T (3 infusions at 2-wk intervals). The primary endpoint is peripheral T cell immune response to PA2024, the immunizing antigen for sipuleucel-T. A secondary endpoint is time to recurrence of elevated serum PSA level.

Results

As of April 7, 2014, 30 enrolled pts had completed sipuleucel-T infusions. At baseline, demographic and disease characteristics in arm A (n = 12) and arm B (n = 18) were generally comparable. Sipuleucel-T product parameters (antigen presenting cell [APC] activation, APC count, and total nucleated cell [TNC] count) did not differ significantly between the arms. A prime-boost effect on APCs was evident in both arms, as indicated by greater APC activation at infusions 2 and 3 than at infusion 1. The nature and incidences of adverse events (AEs) appeared to be similar between the arms and consistent with those previously reported with sipuleucel-T and enzalutamide. Overall, AEs occurred in 6 (50%) pts in arm A and 11 (61%) pts in arm B. Within 1 day of sipuleucel-T infusion, AEs occurred in 3 (25%) pts in arm A and 4 (22%) pts in arm B. No treatment-related grade ≥3 AEs were reported.

Conclusions

Preliminary data suggest that sipuleucel-T potency, prime-boost, and safety are similar with and without concurrent enzalutamide. Data describing sipuleucel-T-induced peripheral immune responses with concurrent vs sequential enzalutamide will be presented at the meeting.

Disclosure

D.P. Petrylak: Consultant or Advisory Role - Dendreon Corporation, Astellas - Self, compensated Corporate-sponsored Research - Dendreon Corporation, Astellas - Self, compensated; D.I. Quinn: Consultant, Honoraria: Dendreon, Medivation, Astellas, Pfizer, Bayer, Aveo, Algeta, Novartis, Amgen, Prometheus, Fresenius, Genentech, Jannsen-Self, compensated Sponsored research: Millenium, Sanofi-Aventis–Self Expert testimony: Medivation, Teva-Self; R. Dreicer: Consultant or Advisory Role: Medivation, Janssen, Dendreon, Roche, Millenium, Sanofi Aventis-Self, compensated Corporate-sponsored research: BIND, Progenics, Roche-Self; E.S. Antonarakis: Consultant or Advisory Role: Dendreon Corporation-Self, compensated Corporate-sponsored Research: Dendreon Corporation-Self; N.D. Shore: Consultant or Advisory Role: Algeta, Astellas, Bayer, Dendreon,Pfizer, Millenium, Janssen, Medivation, Sanofi-Self, compensated; J. Corman: Corporate-sponsored research: Dendreon Corporation-self

R. Concepcion: Consultant or Advisory Role: Dendreon, Algeta, Bayer, MDxHealth, Cardinal Health,Chan Soon-Shiong Institute for Advanced Health-Self, compensated Corporate-sponsored Research: Janssen, Dendreon, Medivation, BNIT-Self; C.M. Pieczonka: Stock Ownership: Algeta-Self Consultant or Advisory Role: Dendreon-Self, compensated Honoraria: Dendreon, Astellas-Self; A.C. Stubbs: Employment: Dendreon Corporation-Self, compensated Stock Ownership: Dendreon Corporation-Self; N. Sheikh: Employment: Dendreon Corporation-Self, compensated Stock Ownership: Dendreon Corporation-Self; T. Devries: Employment: Dendreon Corporation Stock Ownership: Dendreon Corporation; A.S. Sandler: Employment: Dendreon Corporation Stock Ownership: Dendreon Corporation; C.G. Drake: Consultant or Advisory Role: Bristol Myers Squibb, Dendreon, Janssen, Pfizer, Roche-Self, compensated Corporate-sponsored Research: Aduro, Bristol Myers Squibb, Janssen-Self.