Docetaxel and curcuminoids (CCM) combination in patients with castration-resistant prostate cancer (CRPC): A phase II study.

Abstract

e16021 Background: Prostate cancer is a major problem in the aging male population. Docetaxel, the first-line reference treatment in CRPC induces a prostate-specific antigen (PSA) response in 45% of patients and an objective tumor response in 12%. Preclinical studies suggested that curcuminoids inhibit tumor metastasis, invasion and angiogenesis and reverse drug resistance. We wanted to potentiate docetaxel by curcuminoïds in CRPC first line. Our previous phase I study showed the safety and the tolerability of CCM associated to docetaxel for advanced breast cancers. We have conducted in 2009-2010 a phase II study to assess the response of CRPC to this combination. Methods: Patients (n=30) with progressing CRPC and rising PSA were enrolled to receive the experimental treatment. Docetaxel was given in standard conditions (75mg/m², 1h i.v infusion every 3 weeks for 6 cycles + prednisolone) with CCM orally at the dose of 6gr/day (7 days by cycle: d-4 to d+2). The primary endpoint was response rate assessed by biological and paraclinical examinations. The secondary endpoints included safety, time to progression and compliance. Twenty nine patients were evaluable on PSA assessment and 15 on RECIST criteria. Results: 26 patients received the treatment totality and 4 withdrew prematurely. No patient withdrew for toxicity (2 deaths and 2 PSA progressions). A PSA response was observed in 17/29 patients (59%) (4 complete and 13 partial) observed rapidly (before the 3rd cycle) for 15 patients. The median time to subsequent PSA progression (TTP) was 5.8 months. Six patients (40%) had a partial objective response and 9 (60%) a stable disease. The median TTP on targets was 7.85 months (n=13/15). The regimen was well tolerated, with uncommon grade 3/4 toxicity; no adverse event was attributed to CCM. Of 169 cycles, 150 (89%) were completed with perfect compliance. Overall survival was 19 months (mean) and 24 months (median) with 17 events as of december 2012. Conclusions: These results are promising in improving the response rate to docetaxel in terms of both PSA decrease and objective response, with good tolerability and acceptability of CCM. A randomized trial is necessary to confirm this results. Clinical trial information: NCT01012141.