[Updates in hormone-receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast...

Area of Science:

• Oncology
• Pharmacology

Background:

• Hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer remains a significant clinical challenge.
• Cell cycle inhibitors have emerged as a key therapeutic class, showing promise in improving patient outcomes.

Purpose of the Study:

• To review the advancements and clinical significance of cell cycle inhibitors in advanced breast cancer treatment in 2021.
• To highlight emerging therapeutic strategies and novel agents in this field.

Main Methods:

• Review of clinical trial data and published studies from 2021 focusing on cell cycle inhibitors in breast cancer.
• Evaluation of efficacy, safety, and survival data for various therapeutic regimens.

Main Results:

• Cell cycle inhibitors confirmed substantial overall survival benefits, exceeding five years in hormone-sensitive disease.
• Efficacy and safety were validated in the elderly population.
• Investigational agents like SHR6390 and combinations (e.g., palbociclib with SAR439859) are under evaluation.
• Targeting the Phosphoinositide 3-kinases (PI3K) pathway with taselisib showed modest progression-free survival in hormone-resistant disease with PIK3CA mutations, albeit with toxicity concerns.

Conclusions:

• Cell cycle inhibitors are a cornerstone in treating HR+/HER2- advanced breast cancer, offering prolonged survival.
• The development pipeline includes novel inhibitors and combination therapies.
• Targeted pathway inhibition, while promising, requires careful toxicity management.