Preliminary results of a factorial phase II randomized trial of continuous (C) or intermittent (I) docetaxel (DOC) with or without estramustine (E) as first-line treatment for castration-resistant prostate cancer (CRPC) (HOPLITE trial).

Abstract

220 Background: DOC given for 8 consecutive courses is considered a standard first line treatment for CRPC pts and I administration could reduce its impact on quality of life (QL). E is considered synergistic with DOC. Aim of this study was to evaluate in a 2 × 2 factorial design, if I DOC could improve QL compared to C DOC and whether E added to DOC could improve its activity. Methods: CRPC pts were randomized to: C DOC 70 mg/m2 i.v. q 3 wks for 8 courses, alone (arm A) or with E 280 mg/TID p.o. for 5 days starting on -1 day (arm B), or the same treatments given with a 3-month rest period after the first 4 courses (arm C and D, respectively). The primary end points were QL (EORTC QLQ C30 and BPI) of A+B vs C+D and 1-y PFS (according to PCWG2) of A+C vs B+D. Results: From 11/06 to 10/10, 148 CRPC pts were enrolled and 124 pts are presently evaluable (24 too early). The median age was 69 (range 42–81) and the median baseline PSA was 55.6 (range 0.33–4212). The major hematological toxicities were: anemia G3 (3 pts), neutropenia G3 (4 pts) – G4 (5 pts), febrile neutropenia (5 pts). QL outcomes of C and I groups, were not statistically different in terms of general QL items. 1-y PFS was also superimposable (10% and 13.5%, respectively) for DOC and DOC+E groups. The 2-y overall survival was also evaluated with no differences between I and C groups (42.5% and 53.7% respectively) and between DOC and DOC+E groups (42.8% and 53.5% respectively). Conclusions: These preliminary results seem to indicate that I treatment may not improve QL compared to C treatment. Moreover, the addition of E to DOC did not improve 1-y PFS of CRPC pts. Updated data with the complete sample analysis will be presented.