A Study Into The Pharmacodynamic Biomarker Effects Of Olaparib (Parp Inhibitor) Degarelix (Gnrh Antagonist) Given Prior To Radical Prostatectomy (Rp) Cancap03.

35Background: Novel agents given prior to RP allows the study of drug effect(s) in primary human prostate cancer (PC), supporting future clinical study development. Pre-clinical and clinical data (mostly in setting of castration resistant PC) support PARP ± androgen inhibition as therapy for some patients (pt). We undertook a study of olaparib (O) ± degarelix (D) prior to RP. Methods: 20 evaluable (pre and post RP tissue available with 86% dose compliance) pt randomised 1:1 to O or O+D. Primary endpoint: measure PARP inhibition by IHC. Secondary endpoints were feasibility, safety, tolerability. Exploratory objectives: changes PSA, circulating tumour DNA u0026 intra-tumoral immune cells. Men, due for RP, with high volume or aggressive PC, consented and were treated with O (300mg bd) 15 days ± D (240mg once), prior to RP. Diagnostic biopsy and RP tissue were collected. Adverse events (AE) were graded according to CTCAE v4 and followed up to resolution or 6-weeks post RP. Results: 24 men recruited, 4 not evaluab...