RemeGen's Aidixi (disitamab vedotin) has received market approval from China's National Medical Products Administration for a fourth domestic indication, covering adults with unresectable or metastatic HER2-low breast cancer with liver metastases, the company announced on 23 March 2026. The decision marks the first time the HER2-targeted antibody-drug conjugate (ADC) has been authorised in a HER2-low defined population, extending its label beyond the HER2-overexpressing settings for which it was previously approved in gastric cancer, urothelial carcinoma, and HER2-positive breast cancer with liver metastases.
The approved population consists of adult patients with unresectable or metastatic HER2-low breast cancer — defined as IHC 1+ or IHC 2+/ISH-negative — who have liver metastases and have received at least one prior systemic therapy in the metastatic setting, or whose disease recurred during or within twelve months of completing adjuvant chemotherapy.
The NMPA decision rests on data from the Phase III RC48-C012 trial, a randomized, open-label, parallel-controlled, multicenter study conducted in China, the company said. The study (NCT04400695) is a randomized, open-label trial comparing disitamab vedotin with physician’s choice chemotherapy in previously treated patients with HER2-low locally advanced or metastatic breast cancer. The study enrolled adults with prior systemic therapy and was designed to support registrational evaluation against standard-of-care chemotherapy.
The announcement characterised the study as confirming the efficacy and safety of disitamab vedotin in this patient population, though detailed outcome data — including primary endpoints, response rates, and survival figures — were not disclosed in the filing.
Liver metastases represent a clinically distinct and high-unmet-need subset of metastatic breast cancer. According to GLOBOCAN 2022 data cited by RemeGen, approximately 2.3 million new breast cancer cases and 670,000 deaths occur globally each year; in China, the figures are approximately 357,000 new cases and 75,000 deaths annually. Liver involvement occurs in an estimated 17.8% to 35% of metastatic breast cancer patients and carries a five-year survival rate of approximately 20%. Within the HER2-low subgroup — which accounts for roughly 45% to 55% of all breast cancer cases — the three-year survival rate is approximately 20%, with around one-third of patients experiencing recurrence or metastasis and a notably worse prognosis in those with visceral involvement.