|The following article features coverage from the American Society of Clinical Oncology (ASCO) 2019 meeting.|
Adding apalutamide to androgen deprivation therapy (ADT) for metastatic castration-sensitive prostate cancer (mCSPC) significantly improves outcomes, according to study findings presented at the 2019 American Society of Clinical Oncology annual meeting in Chicago and published the same day in the New England Journal of Medicine.
In the phase 3 double-blind TITAN trial, men with mCSPC who received apalutamide plus ADT experienced a significant 52% decreased risk of death or radiographic progression compared with those who received placebo plus ADT, Kim N. Chi, MD, of BC Cancer and Vancouver Prostate Centre in Vancouver, British Columbia, and colleagues reported. The apalutamide-treated patients also had a significant 33% decreased risk of death. Median radiographic progression-free survival (rPFS) was 22.1 months in the placebo arm and not reached in the apalutamide group. Median overall survival was not reached in either study arm.
In addition, apalutamide recipients had a significant 61% decreased risk of initiating cytotoxic chemotherapy, according to investigators.
Based on study findings, the trial’s independent monitoring committee recommended unblinding to allow patients in the placebo group to cross over the apalutamide arm.
In the TITAN (Targeted Investigational Treatment Analysis of Novel Anti-androgen) trial, Dr Chi and colleagues randomly assigned 525 patients to receive apalutamide 240 mg per day plus ADT and 527 to receive placebo plus ADT. Patients had a median age of 68 years. Of the entire study population, 16.4% had undergone prostatectomy or received radiotherapy, 10.7% had received prior docetaxel therapy, and 62.7% had high-volume disease.
At the first interim analysis, with a median 22.7 months of follow-up, the proportion of men with rPFS at 24 months was 68.2% in the apalutamide arm and 47.5% among placebo recipients. At 24 months, the overall survival rate was significantly higher in the apalutamide than placebo group: 82.4% vs 73.5%.
The rates of grade 3 or 4 adverse events were similar in the apalutamide and placebo groups: 42% and 41%, respectively. The rates of study discontinuation due to AEs were 8% and 5%, respectively.
Based on the TITAN findings, Janssen Pharmaceutical Companies, which developed apalutamide (Erleada), submitted a supplemental New Drug Application to the FDA seeking approval of apalutamide for the treatment of men with mCSPC. Apalutamide already is approved the treatment of nonmetastatic castration-resistant prostate cancer.
Chi KN, Agarwal N, Bjartell A, et al. First results from TITAN: A phase III double-blind, randomized study of apalutamide (APA) versus placebo (PBO) in patients (pts) with metastatic castration-sensitive prostate cancer (mCSPC) receiving androgen deprivation therapy (ADT). Presented at the 2019 American Society of Clinical Oncology annual meeting in Chicago, May 31 to June 4. Abstract 5006.
Chi KN, Agarwal N, Bjartell A, et al. Apalutamide for metastatic, castration-sensitive prostate cancer. N Engl J Med. 2019; doi:10.1056/NEJMoa1903307