Phase II study of tasquinimod in chemotherapy-naive patients with metastatic castrate-resistant prostate cancer (CRPC): Safety and efficacy analysis including subgroups.
, Journal Article
Armstrong, AJ; Haggman, M; Stadler, WM; Gingrich, JR; Assikis, VJ; Nordle, O; Forsberg, G; Carducci, MA; Pili, R
Published in: Journal of Clinical Oncology
126 Background: Tasquinimod (TASQ) is an oral quinoline-3-carboxamide derivative that binds to S100A9 and displays anti-angiogenic and anti-tumor activity in prostate cancer (PC) models. In a randomized blinded phase II study, 206 (136 TASQ, 70 placebo [P]) men with metastatic castrate resistant (CRPC) were assigned to TASQ/P once-daily at an initial dose level of 0.25 mg/day escalating to 1.0 mg/day over 4 weeks. The primary endpoint to demonstrate an improvement in PCWG2 criteria-defined progression at 6 months was met and presented at ASCO 2010. This abstract provides an update on safety and efficacy including CRPC subgroups. Methods: Subgroups of patients based on baseline criteria were investigated for safety using NCI CTC v 3.0 criteria, PK and efficacy. Results: 201 (134 TASQ, 67 P) pts with a median age of 72.6 years received treatment and were evaluable for efficacy and safety. The updated analysis based on 5 additional PFS events confirmed an improved PFS of 7.6 vs. 3.3 months for pts on TASQ vs. P. Most progression events in both arms were radiological, but more pts progressed on bone scan in the P group. Radiographic PFS was 8.8 vs 4.4 months. Significant PFS improvements were observed in the PCWG2 risk groups with bone metastatic and visceral disease. TASQ treatment led to a transient increase in inflammatory lab markers such as CRP and fibrinogen, as well as asymptomatic increases in amylase/lipase. CRP increase was associated with adverse events (AEs) such as muscle and joint pain, while increased amylase was associated with a lower risk for gastrointestinal AEs. TASQ treatment was associated with anaemia, but did not affect CV risk factors such as hypertension or QTc prolongation, and the rate of composite cardiac events was acceptably low. Clearance of TASQ is decreased with age (1.4 % per year) and patients over 80 often required dose reduction due to increased exposure and toxicities. Conclusions: TASQ improved PFS in men with metastatic CRPC. Side effects are manageable and seem to correlate with laboratory markers. Individualized dosing based on tolerability is recommended and a phase III placebo-controlled study is being initiated. [Table: see text]