Alisertib for Breast Cancer

This trial explores whether adding alisertib, a new potential drug, to regular treatments can combat HR+/HER2+ breast cancer, which involves proteins that promote cancer growth. Researchers aim to determine if alisertib can block these proteins and identify genetic markers indicating its effectiveness. Participants will continue their usual treatment while taking alisertib. The trial seeks individuals with HR+/HER2+ breast cancer who have undergone chemotherapy and are currently on other cancer-fighting medications. As a Phase 2 trial, this research focuses on assessing the treatment's effectiveness in an initial, smaller group of participants.

Research has shown that alisertib, when combined with other treatments, offers potential benefits but also presents some safety concerns. In earlier studies, the most common serious side effects included low levels of white blood cells (neutropenia and leukopenia) and low red blood cell count (anemia), affecting many patients. For instance, one study found that 84.8% of patients taking paclitaxel and alisertib together experienced serious side effects. However, other research indicated that alisertib was generally well tolerated, with common but less severe side effects such as mouth inflammation (stomatitis).

Alisertib is unique because it targets a specific protein called Aurora A kinase, which plays a crucial role in cell division and is often overactive in cancer cells. Unlike traditional chemotherapy treatments for breast cancer that broadly attack dividing cells, alisertib offers a more targeted approach that could potentially lead to fewer side effects. Researchers are excited about alisertib because its specific mechanism might enhance the effectiveness of standard treatments, potentially improving outcomes for patients with breast cancer.

Research suggests that alisertib may help treat certain types of breast cancer. In this trial, participants will receive alisertib alongside the standard of care. Studies have shown that when combined with other treatments, alisertib led to a reduction in tumor size in about 1 in 5 patients. Additionally, it has been linked to slowing cancer progression for approximately 5.4 to 5.6 months. While side effects, such as a decrease in white blood cells, can occur, these early findings indicate that alisertib could be effective for HR+/HER2+ breast cancer.¹⁴⁵⁶⁷