AZD-5312

Prostate cancer is the most common cancer in men. Regardless of the initial treatment of localized disease, almost all patients develop castration resistant prostate cancer (CRPC). A better understanding of the molecular mechanisms behind castration resistance has led to the approval of novel oral androgen receptor (AR) antagonists, such as enzalutamide and apalutamide. Indeed, research has accelerated with numerous agents being studied for the management of CRPC. Areas covered: Herein, the authors present currently used and emerging AR antagonists for the treatment of CRPC. Emerging agents include darolutamide, EZN-4176, AZD-3514, and AZD-5312, apatorsen, galeterone, ODM-2014, TRC-253, BMS-641988, and proxalutamide. Expert opinion: Further understanding of the mechanisms leading to castration resistance in prostate cancer can reveal potential targets for the development of novel AR antagonists. Current novel agents are associated with modest clinical and survival benefit, while acquired resistance and safety issues are under continuous evaluation. The combination of AR antagonists used and ideal sequencing strategies are key tasks ahead, along with the investigation of molecular biomarkers for future personalized targeted therapies. In the future, the challenge will be to determine an AR antagonist with the best combination of outcome and tolerability.

Limited data exist on the adoption of rituximab biosimilars vs the reference product by indication. Available data from real-world studies comparing rituximab biosimilar and reference use have focused predominantly on oncology indications. This is the first study to assess the utilization of the 3 US rituximab biosimilars vs the reference product.

Comparative analysis.

Deidentified real-world data of rituximab, rituximab-abbs, rituximab-pvvr, and rituximab-arrx dispensations between December 31, 2018, and February 1, 2022, were extracted using Trisus Medication Compare (The Craneware Group). The primary outcome was rituximab reference vs biosimilar utilization for oncology vs nononcology indications. Results were stratified by on-label and off-label use and treatment settings.

A total of 28,025 encounters were captured for rituximab and its biosimilars across 193 facilities (rituximab: n = 23,395; biosimilars, n = 4631 [rituximab-abbs: n = 2550; rituximab-pvvr, n = 2081; rituximab-arrx: n = 0]). Rituximab reference had higher dispensations for oncology (78.4%) and nononcology (88.3%) indications than its biosimilars (21.6% and 11.7%, respectively; P < .01). The 3-year annual trends from 2019 to 2021 revealed decreased rituximab reference utilization (99.99% to 40.1%) and increased biosimilar use (0.01% to 59.9%). Most oncology dispensations were on label (94.5%), whereas most nononcology dispensations were off label (73.6%; P < .01). A higher proportion of biosimilar use was attributed to on-label indications (67.7%; off-label, 32.2%) compared with rituximab reference (58.0% vs42.0%, respectively; P < .01). Nonacademic settings showed higher biosimilar adoption than academic settings (22.2% vs 10.3%, respectively; P < .01).

Real-world evidence shows an increase in rituximab biosimilar adoption over time, with higher adoption for oncology vs nononcology indications and in nonacademic settings.