A comprehensive review of biomarker-based therapies for hormone receptor-positive and HER2-low breast cancer: clinical pharmacists' implications

Jayesh R. C. Pandey; Gajendra N. Vyas; Esha H. Dutta; Shiwani K. Shah; Hirni J. Patel

doi:10.18203/2319-2003.ijbcp20261129

Authors

Jayesh R. C. Pandey Department of Pharmacy Practice, Parul Institute of Pharmacy and Research, Parul University, Vadodara, Gujarat, India https://orcid.org/0009-0005-2586-8847
Gajendra N. Vyas Department of Pharmacy Practice, Parul Institute of Pharmacy and Research, Parul University, Vadodara, Gujarat, India https://orcid.org/0009-0007-4065-5166
Esha H. Dutta Department of Pharmacy Practice, Parul Institute of Pharmacy and Research, Parul University, Vadodara, Gujarat, India https://orcid.org/0009-0003-0500-9098
Shiwani K. Shah Department of Pharmacy Practice, Parul Institute of Pharmacy and Research, Parul University, Vadodara, Gujarat, India https://orcid.org/0009-0005-9209-2698
Hirni J. Patel Department of Pharmacy Practice, Parul Institute of Pharmacy and Research, Parul University, Vadodara, Gujarat, India https://orcid.org/0000-0002-1881-0672

DOI:

https://doi.org/10.18203/2319-2003.ijbcp20261129

Keywords:

Breast cancer, HER2-negative, Inavolisib, Datopotamab deruxtecan, Imlunestrant

Abstract

The purpose of this review is to outline the role of clinical pharmacist's in implementing precision oncology and to synthesize current evidence on biomarker-driven targeted therapies in metastatic breast cancer delivers significant regulatory approvals from 2024 to 2025. A thorough literature search was carried out using Scopus, PubMed and conference materials from the European Society for Medical Oncology (ESMO) and the American Society of Clinical Oncology (ASCO). Breast neoplasms, molecular targeted therapy, PIK3CA, ESR1, Trop-2, and clinical pharmacy were among the most important search terms. Phase III randomized controlled trials and recent notifications derived from the U. S. Food and Drug Administration (FDA) were top prioritized during the selection process. From empirical hormonal blockade to a important molecular taxonomy, the therapy of hormone receptor-positive, human epidermal growth factor receptor 2-negative metastatic breast cancer has changed. Management of hormone receptor-positive, HER2-negative metastatic breast cancer shows differentiated from empirical hormonal blockade to a precise molecular taxonomy. In "HER2-low" illness, which is characterized as IHC 1+ or 2+ with ISH negative, trastuzumab and deruxtecan significantly improved results. Furthermore, the approval of inavolisib, datopotamab deruxtecan, and imlunestrant in 2024–2025 marks a regulatory turning point in HR-positive illness. The pharmacists must monitor these drugs closely as they have improved progression-free survival, but they also have some side effects, such as hyperglycemia, stomatitis, and ILD. Biomarker-driven therapy is the benchmark synonym for metastatic breast carcinoma with hormone receptor positivity and low HER2 expression. Biomarker-driven therapy is the current evidence-based practice standard for metastatic hormone receptor-positive and HER2-low breast cancer. Clinical pharmacists play a crucial role in the successful implementation of these complex regimens because they must manage diagnostic stewardship, treatment sequencing, and specific adverse effects to ensure complete patient safety.

Author Biography

Esha H. Dutta, Department of Pharmacy Practice, Parul Institute of Pharmacy and Research, Parul University, Vadodara, Gujarat, India

Performed detailed literature review and prepared the initial draft of the manuscript.

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