Posted: Tuesday, July 18, 2023
Based on previous data from the phase III TALAPRO-2 trial, patients with metastatic castration-resistant prostate cancer derived a radiographic progression–free survival benefit from first-line treatment with the PARP inhibitor talazoparib plus the androgen receptor inhibitor enzalutamide, according to Arun Azad, MBBS, PhD, FRACP, of the Peter MacCallum Cancer Centre, Melbourne, Australia, and colleagues. The results of a safety analysis, which were presented during the 2023 American Society for Clinical Oncology (ASCO) Annual Meeting (Abstract 5053), support a “generally manageable” safety profile for this combination.
“A detailed understanding of the onset, duration, and severity of adverse events, as well as the impact of dose adjustments in the TALAPRO-2 study, will optimize the management of patients receiving talazoparib plus enzalutamide for metastatic castration-resistant prostate cancer,” the investigators commented.
In this trial, patients who were undergoing androgen-deprivation therapy were randomly assigned to receive 160 mg of enzalutamide once daily plus either 0.5 mg of talazoparib or a placebo. Of those who were administered the experimental combination treatment, 398 were included in the homologous recombination repair gene alteration–unselected safety cohort. The median duration of treatment with talazoparib was 19.8 months. Most patients (98.5%) experienced all-cause any-grade treatment-emergent adverse events. A total of 19.1% of patients discontinued treatment with talazoparib because of treatment-emergent adverse events.
Anemia (65.8%), neutropenia (35.7%), and thrombocytopenia (24.6%) were the most frequently reported hematologic all-cause treatment-emergent adverse events. At study entry, 49.0% of patients had grade 1 or 2 anemia; the median duration of time to onset of anemia of grade 3 or higher was 3.3 months. A total of 43.2% and 8.3% of patients underwent dose reduction or discontinuation of talazoparib because of anemia, respectively. The most commonly reported nonhematologic treatment-emergent adverse events were fatigue (33.7%), back pain (22.1%), and decreased appetite (21.6%).
Disclosure: For full disclosures of the study authors, visit coi.asco.org.