Effect of Chinese herbal medicine formula on progression-free survival among patients with metastatic colorectal cancer: Study protocol for a multi-center, double-blinded, randomized, placebo-controlled trial

Introduction Metastatic colorectal cancer (mCRC) causes high cancer-related morbidity and mortality worldwide. Although chemotherapy and targeted agents treatment improve median survival and 5-year survival rates, there is only one-third of patients who adhere to treatment protocol until the pause of disease progression. Hezhong granule is a traditional Chinese herbal formula used for mCRC, which has shown good potential in alleviating the adverse effects of chemotherapy, enhancing the effectiveness of chemotherapy, and improving the quality of life. Therefore, the purpose of the study is to further validate the clinical efficacy and safety of the Chinese herbal medicine formula named Hezhong (HZ) in combination with standard chemotherapy and cetuximab (CET) or bevacizumab (BV) for treating mCRC. Methods In this multi-center, randomized, double-blinded, placebo-controlled trial, 360 eligible mCRC patients who will be randomly assigned to Hezhong or placebo group with a 1: 1 ratio. Participants in the Hezhong group will receive standard chemotherapy and CET or BV plus Hezhong Granule until the pause of disease progression, death, the exhibition of intolerable toxicity, or up to 6 months, while the placebo group will treat with standard chemotherapy and CET or BV plus placebo. The primary endpoint is progression-free survival (PFS). The secondary endpoints are overall survival (OS), objective response rate (ORR), safety, quality of life years (QOL), and chemotherapy-induced nausea and vomiting (CINV). Expected results The expected results of this trial are to improve the PFS and QOL of patients with mCRC and provide evidence-based recommendations for the treatment of mCRC with traditional Chinese medicine in China. Trial registration The trial has been registered with the Chinese Clinical Trial Registry (ChiCTR). The trial registration number was ChiCTR2100041643 .