Novel androgen receptor signaling inhibitors for prostate cancer (PC) impose the burden of self-administration on older patients overwhelmed by the requirement of many other concomitant medications.
This study evaluated the proportion of non-adherence in a 12-month follow-up period and the first 3 months to abiraterone (ABI) or enzalutamide (ENZ). In a prospective multicenter observational cohort study, patients with metastatic castration-resistant PC (mCRPC) aged ≥70 years receiving ABI or ENZ pre- or post-docetaxel were enrolled. Treatment monitoring included pill counting, a self-assessment questionnaire, and clinical diaries at each clinical visit. Non-adherence rates were based on proportions of missed/prescribed pills ratios by pill counting.
Overall, 234 patients were recruited with median age of 78 years (range, 73-82); 86 (37%) were treated with ABI, and 148 (63%) with ENZ. The median follow-up for adherence was seven monthly cycles (IQR: 4-12). The two cohorts were well balanced for baseline characteristics. The percentage of non-adherence by pill counting was slightly higher for ABI than ENZ (5.2% vs. 4.2%, P < .001). By self-reporting, patients on ENZ tended to report more frequently than those with ABI forgetfulness as the reason for missing events (42% vs. 17%, P < .001). A lower Geriatric G8 score correlated with non-adherence (P = .004). Overall survival (OS) was 48.8 months. Patients on ABI had radiographic progression-free survival (rPFS) of 28.4 [24.2-32.5], while for ENZ patients, we reported a median rPFS of 23.1 [18.2-28.1] months.
Physicians tend to treat older mCRPC patients with ENZ. Non-adherence rate is relatively low overall but can be higher with ABI than with ENZ and correlates with the Geriatric G8 score. Forgetfulness is a potential barrier for ENZ.
The oncologist. 2022 Aug 03 [Epub ahead of print]
Pasquale Rescigno, Marco Maruzzo, Sara Elena Rebuzzi, Veronica Murianni, Marika Cinausero, Helga Lipari, Lucia Fratino, Teresa Gamba, Ugo De Giorgi, Orazio Caffo, Davide Bimbatti, Arianna Dri, Alessandra Mosca, Emilio Francesco Giunta, Paola Ermacora, Francesca Vignani, Aichi Msaki, Barbara Bonifacio, Valentina Lombardo, Vincenza Conteduca, Umberto Basso, Giuseppe Fornarini, Giuseppe Luigi Banna
Candiolo Cancer Institute, FPO-IRCCS, Turin, Italy., Medical Oncology 1 Unit, Department of Oncology, Istituto Oncologico Veneto IOV IRCCS, Padova, Italy., Medical Oncology Unit, Ospedale San Paolo, Savona, Italy., Medical Oncology Unit 1, IRCCS Ospedale Policlinico San Martino, Genova, Italy., Department of Oncology, ASUFC Santa Maria Della Misericordia, Udine, Italy., Division of Medical Oncology, Cannizzaro Hospital, Catania, Italy., Department of Medical Oncology, Centro di Riferimento Oncologico di Aviano CRO-IRCCS, Aviano, Italy., Medical Oncology, Mauriziano Hospital,Turin, Italy., Department of Medical Oncology, IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) "Dino Amadori", Meldola, Italy., Department of Medical Oncology, Santa Chiara Hospital, Trento, Italy., Department of Medical and Surgical Sciences, Unit of Medical Oncology and Biomolecular Therapy, University of Foggia, Policlinico Riuniti, Foggia, Italy.