Puma Biotechnology initiates ALISCA™-Breast1 Phase II trial of alisertib with endocrine therapy for hormone receptor-positive, HER2-negative metastatic breast cancer. The trial will enroll up to 150 patients previously treated with CDK 4/6 inhibitors and at least two endocrine therapies, randomized to receive alisertib at 30mg, 40mg, or 50mg doses. Primary endpoints include objective response rate, duration of response, disease control rate, progression-free survival, and overall survival. Initial data expected in 2025, with plans to discuss potential approval pathways with the FDA.