Puma Biotechnology Begins Phase II Trial of Alisertib for Metastatic Breast Cancer

Puma Biotechnology, Inc., a prominent biopharmaceutical company listed on NASDAQ under the ticker PBYI, has recently announced the initiation of the ALISCA™-Breast1 Phase II clinical trial (PUMA-ALI-1201; NCT06369285). This trial is set to investigate the efficacy of alisertib in combination with endocrine therapy for treating patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-negative) recurrent or metastatic breast cancer. These patients have previously been treated with CDK 4/6 inhibitors and have undergone at least two prior lines of endocrine therapy in the recurrent or metastatic setting.

The ALISCA™-Breast1 trial aims to enroll up to 150 participants, who will be randomly assigned to one of three groups (1:1:1) to receive alisertib at doses of either 30 mg, 40 mg, or 50 mg twice daily on specific days in a 28-day cycle. This treatment will be combined with the investigator's choice of endocrine therapy. Participants will also need to provide blood and tissue samples for biomarker analysis.

The primary goal of the trial is to determine the optimal dose of alisertib when used with selected endocrine therapies. Primary endpoints include the objective response rate, duration of response, disease control rate, progression-free survival, and overall survival. As secondary endpoints, Puma will evaluate these efficacy metrics within biomarker subgroups to determine if any specific biomarker correlates with response. The biomarker analysis will be conducted in parallel with the clinical trial execution, and an initial interim analysis focusing on safety and efficacy is planned.

Based on the trial's outcomes, Puma Biotechnology plans to engage with the U.S. Food and Drug Administration to discuss potential approval pathways for alisertib in HER2-negative, HR+ metastatic breast cancer. Once the optimal dose is identified, Puma intends to collaborate with global regulatory agencies to design a pivotal Phase III trial. This trial will likely be a randomized study comparing alisertib plus investigator's choice of endocrine therapy against a placebo plus investigator's choice of endocrine therapy for patients with HER2-negative, HR+ metastatic breast cancer.

Dr. Joyce A. O’Shaughnessy, a renowned breast cancer researcher at Baylor University Medical Center and other institutions, emphasized the need for additional therapies for patients whose disease progresses after CDK4/6 inhibitors. She expressed optimism about the further evaluation of alisertib in the ALISCA™-Breast1 trial, referencing the promising results from the TBCRC 041 trial, which demonstrated significant clinical activity and tolerability of alisertib in a similar patient group.

Alan H. Auerbach, the CEO, President, and Founder of Puma Biotechnology, expressed enthusiasm about the initiation of this Phase II trial. He highlighted previous studies published in esteemed journals such as Lancet Oncology and JAMA Oncology, which have shown alisertib's efficacy in patients with HER2-negative, HR+ metastatic breast cancer, both as monotherapy and in combination with other treatments. Auerbach anticipates initial data from the ALISCA™-Breast1 trial to be available by 2025.

Puma Biotechnology focuses on developing and commercializing innovative cancer therapies. The company has in-licensed global development and commercialization rights for neratinib (PB272), approved by the FDA for various indications related to HER2-positive breast cancer and marketed as NERLYNX®. In 2022, Puma secured an exclusive license to develop and commercialize alisertib, initially targeting small cell lung cancer and breast cancer. The ALISCA™-Lung1 Phase II trial for small cell lung cancer and the ALISCA™-Breast1 Phase II trial for breast cancer are key components of their ongoing research efforts.