A “Chinese solution” has emerged for the most aggressive breast cancer treatment, with a 12% increase in the complete remission rate.

Triple-negative breast cancer (TNBC) accounts for approximately 10%-20% of all newly diagnosed breast cancer cases. This disease is characterized by a high risk of recurrence and poor treatment efficacy, often earning it the label of the most “aggressive” form of breast cancer.

During the 47th Annual San Antonio Breast Cancer Symposium held from December 10 to 13, 2024, a key clinical trial (Phase III) led by Professor Zhao Zhimin from the Fudan University Shanghai Cancer Center was presented, which could change the neoadjuvant treatment approach for TNBC. The research indicated that combining conventional chemotherapy with the Chinese-developed immunotherapy drug Camrelizumab (a PD-1 monoclonal antibody) increased the pathological complete response rate in TNBC patients by 12.1% (from 44.7% to 56.8%), significantly outperforming current chemotherapy regimens.

The landmark study was also published simultaneously in the Journal of the American Medical Association (JAMA), one of the four major international medical journals, marking the first time in its 141-year history that JAMA published a study on a breast cancer innovative drug based on the Chinese population, thus providing strong evidence for a “Chinese solution” in the neoadjuvant immunotherapy for TNBC.

With a focus on the Chinese TNBC patient population, this original drug clinical research targets the specifics of TNBC. Pathologically, breast cancer consists of four molecular subtypes: Luminal A, Luminal B, HER2-positive, and TNBC.

“Unlike other subtypes, TNBC lacks three key therapeutic targets: estrogen receptor, progesterone receptor, and HER2. This makes TNBC generally unresponsive to endocrine therapy and HER2-targeted therapy, relying primarily on chemotherapy for systemic treatment, which is less effective compared to other breast cancer types,” said Professor Zhao.

Currently, patients with early or locally advanced TNBC typically undergo neoadjuvant chemotherapy before surgery to shrink the tumor. Achieving pathological complete response can significantly enhance treatment outcomes. The standard neoadjuvant therapy regimen for TNBC is chemotherapy based on taxanes, anthracyclines, and cyclophosphamide.

“Despite the standard treatment showing some efficacy, clinical exploration for further optimizing treatment strategies is ongoing. In recent years, researchers have attempted to incorporate immunotherapy into standard chemotherapy regimens. Clinical studies have confirmed that adding immunotherapy, such as PD-1 or PD-L1 monoclonal antibodies, to traditional chemotherapy can substantially improve the pathological complete response rate and extend survival,” Zhao explained.

However, most existing large studies have been based on Western populations and have not benefitted all domestic TNBC patients, particularly those with extensive lymph node metastasis, who still see no advantage from optimized treatment plans.

Based on this clinical need, Zhao turned his attention to the domestic original drug, Camrelizumab. “This is an effective PD-1 immune checkpoint inhibitor, whose efficacy has been well-validated in advanced or metastatic TNBC. We considered combining Camrelizumab with neoadjuvant chemotherapy for TNBC to explore further opportunities to enhance patient outcomes,” Zhao added.

To this end, Zhao serves as the principal investigator leading a clinical study named CamRelief, involving a total of 40 clinical centers across the country.

Notably, all patients enrolled in the CamRelief study were from the Chinese population. According to the study design, 441 cases of early or locally advanced TNBC were included, receiving either neoadjuvant Camrelizumab combined with chemotherapy or a placebo, followed by up to one year of continued treatment with either Camrelizumab or placebo after surgery.

The study revealed that patients who received Camrelizumab in addition to the standard chemotherapy showed a pathological complete response rate of 56.8% after a median follow-up of 14.4 months, significantly outperforming the control group’s 44.7%, with an absolute benefit of 12.1%.

The research further confirmed that regardless of patient age, physical condition, lymph node status, clinical stage, or PD-L1 score, the treatment efficacy of the Camrelizumab chemotherapy group was higher than that of the placebo chemotherapy group. Additionally, the safety of adding Camrelizumab was manageable, with no unexpected adverse reactions reported compared to previous findings.

“This is an exciting research outcome. Adding Camrelizumab to traditional chemotherapy increased the effectiveness of neoadjuvant treatment for patients by over 10%, with benefits observed across all subgroups,” Zhao emphasized. “While significantly enhancing the neoadjuvant efficacy for TNBC patients, this treatment regimen also shows manageable safety, potentially transforming clinical practice in neoadjuvant treatment.”

Experts noted that currently, only about 30% of TNBC patients in China benefit from foreign drugs such as the PD-1 inhibitor Pembrolizumab (commonly known as Keytruda), which were not included in clinical trials involving Chinese patients, and the indications for Keytruda are also limited, making it hard to cover all patient populations. “Through clinical trials based on the Chinese population and original immunotherapy drugs developed in China, we aim to expand the beneficiary cohort of TNBC patients, enabling more patients to gain access to effective treatments and improving their survival rates. We also aim to enhance the accessibility of innovative drugs.”

Zhao also emphasized that the current clinical trial is not yet a registered clinical study. For this original domestic pharmaceutical to reach the market, it will need to apply for registration with the national drug supervision authorities, requiring further research.

“We are continuously researching which types of TNBC patients are more likely to relapse and what measures can be taken to reduce recurrences. If TNBC patients do not experience a relapse within five years, they can essentially be considered ‘cured’,” Zhao noted. This year, Zhao’s team at the Fudan University Shanghai Cancer Center has also established a Breast Cancer Precision Treatment Collaborative Group aimed at conducting multi-center clinical research on personalized breast cancer treatment and building a Chinese platform for translational breast cancer research, with hopes to benefit a wide range of breast cancer patients globally through more original Chinese solutions.