Editor's Note: The 47th San Antonio Breast Cancer Symposium (SABCS) will be held from December 10 to 13, 2024, in San Antonio, USA. A phase II prospective study led by Professors Huiping Li and Hanfang Jiang from Peking University Cancer Hospital will be presented as a poster (Abstract No: P1-02-12). This study explores the efficacy and safety of hetrombopag monotherapy in treating cancer therapy-induced thrombocytopenia (CTIT) in breast cancer patients. Preliminary findings show that hetrombopag achieves a high treatment response rate, rapidly improves platelet (PLT) levels, and demonstrates excellent efficacy and tolerance without severe adverse events, particularly no thrombosis. These results confirm the potential of hetrombopag as a novel therapeutic option for CTIT in breast cancer patients, providing new evidence-based data. As the research progresses, hetrombopag is expected to play a greater role in improving treatment outcomes for breast cancer patients undergoing antitumor therapy.

Hetrombopag is a novel, small-molecule, non-peptide thrombopoietin receptor agonist (TPO-RA) developed in China. It selectively binds to the transmembrane region of the TPO receptor (TPO-R), activating STAT and MAPK signaling pathways in a TPO-R-dependent manner. This effectively stimulates megakaryocyte proliferation and differentiation. Notably, it does not compete with endogenous TPO at binding sites, enabling it to synergize with endogenous TPO to promote platelet production. Hetrombopag is administered orally.

On June 17, 2021, the National Medical Products Administration (NMPA) approved hetrombopag for adult patients with chronic immune thrombocytopenia (ITP) who do not respond adequately to glucocorticoids, immunoglobulins, or other therapies, as well as adult patients with severe aplastic anemia (SAA) refractory to immunosuppressive therapy.

The current study results demonstrate that hetrombopag monotherapy shows a high response rate in treating CTIT in breast cancer patients, rapidly improving PLT levels with excellent efficacy and safety. This provides new evidence supporting the use of TPO-RAs in CTIT treatment.

Huiping Li

• Director, Department of Breast Oncology, Peking University Cancer Hospital
• Chief Physician, Professor, PhD Supervisor, MD
• Two-year research experience at MD Anderson Cancer Center, University of Texas
• Chair, Breast Committee, Chinese Medical Women’s Association
• Vice-Chair, Breast Cancer Group, Chinese Medical Association
• Standing Member, Breast Cancer Committee, Chinese Anti-Cancer Association
• Vice-Chair, Clinical Oncology Committee, Chinese Medical Women’s Association
• Co-Chair and Lead Author, Consensus Guidelines for Advanced Breast Cancer in China
• Associate Editor, Breast Cancer Research and Treatment

Hanfang Jiang

• Associate Chief Physician, Department of Breast Oncology, Peking University Cancer Hospital
• Member, Clinical Research Management Committee, Peking University Cancer Hospital
• Member, Breast Cancer Committee, Chinese Anti-Cancer Association
• Standing Member, Clinical Research Committee, Chinese Medical Education Association
• Standing Member, Breast Committee, Chinese Medical Women’s Association
• Standing Member, Multidisciplinary Tumor Prevention Committee, China Association for the Promotion of Traditional Chinese Medicine Research
• Standing Member, Breast Cancer Committee, Beijing Chronic Disease Prevention and Health Education Association
• Member, Breast Cancer Targeted Therapy Committee, Beijing Anti-Cancer Association
• Member, Health Management Committee, Beijing Breast Disease Prevention Association
• Visiting Scholar, UCSF Medical Oncology Center