Apalutamide offers similar HRQoL vs ADT alone in nonmetastatic castration-resistant prostate cancer
Men with nonmetastatic castration-resistant prostate cancer (CRPC) have similar health-related quality of life (HRQoL) with apalutamide given on top of androgen deprivation therapy (ADT) vs ADT alone, according to new data from the SPARTAN (Prostate Androgen Receptor Targeting with ARN-509) trial presented at the European Association of Urology (EAU) 2018 Congress.
In the phase III trial, 1,207 patients with nonmetastatic CRPC who had a prostate-specific antigen (PSA) doubling time of ≤10 months were randomized in a 2:1 ratio to receive oral apalutamide (240 mg daily) or placebo in addition to ADT (either with a gonadotropin-releasing hormone analogue or surgical castration). [N Engl J Med 2018;378:1408-1418]
After a median follow-up of 20.3 months, apalutamide was associated with a 72 percent reduction in the risk of metastasis and a 2-year extension in metastasis-free survival compared with placebo (median, 40.5 months vs 16.2 months; hazard ratio [HR], 0.28; p<0.0001). These results led to the US FDA’s approval of apalutamide in February 2018 as the first drug for nonmetastatic CRPC.
In the SPARTAN trial, patients’ HRQoL was assessed using self-reported questionnaires, including the Functional Assessment of Cancer Therapy-General (FACT-G), Functional Assessment of Cancer Therapy-Prostate (FACT-P) and EuroQoL Group EQ-5D-3L questionnaires. These questionnaires were completed at baseline, on day 1 of cycles 2–7, cycle 9, cycle 11 and cycle 13, and subsequently every 4 months for the duration of treatment, as well as at 1 year after treatment discontinuation.
At baseline, the mean FACT-G score was 83/108 in the apalutamide arm and 84/108 in the placebo arm, which were comparable to the mean score of adult patients without prostate cancer (81/108).
Analysis showed that mean changes from baseline in FACT-P total score and all subscores were not significantly different between patients receiving apalutamide plus ADT and those receiving placebo plus ADT.
Furthermore, FACT-G scores and other patient-reported scores were maintained in the apalutamide arm.
“In fact, HRQoL was not only maintained in the apalutamide arm – it might be slightly better compared with patients in the placebo arm,” said co-investigator Professor Fred Saad of the University of Montreal in Quebec, Canada.
According to Saad, it was very important to evaluate the patients’ quality of life. “This is because patients with nonmetastatic CRPC are asymptomatic by definition, and treatment with an active agent could lead to a worsening in quality of life,” he explained.
“Our results also suggest that treatment with drugs such as apalutamide should not be delayed for patients with CRPC who are at high risk of metastasis,” Saad added. “Although patients in the placebo arm were treated with apalutamide upon the development of metastasis, the survival curves continued to separate between the two study arms. In other words, they did not do as well as patients who were started on apalutamide early.”