First Patient Dosed in Phase III Study of JSKN003 for HER2-positive Breast Cancer

Alphamab Oncology, a leading biopharmaceutical company, announced today that the first patient has been dosed in a Phase III clinical study (JSKN003-301) of its anti-HER2 biparatopic antibody-drug conjugate (ADC), JSKN003, for the treatment of HER2-positive advanced breast cancer. This marks a significant milestone in the development of JSKN003 and underscores the company's commitment to addressing unmet clinical needs in oncology.

JSKN003 is a novel anti-HER2 bispecific ADC developed in-house by Alphamab Oncology using its proprietary Glycan-specific conjugation platform. The drug has shown promising results in early-stage clinical trials, demonstrating favorable tolerability, safety, and encouraging anti-tumor activity. In a Phase I/II clinical study conducted in China, JSKN003 exhibited an overall response rate (ORR) of 51.1% and a disease control rate (DCR) of 93.3% in patients with advanced solid tumors. Additionally, JSKN003 has shown efficacy signals in patients with previous anti-HER2 ADC treatment, with an ORR of 57.1% in 28 patients and 57.1% in 21 patients, respectively.



The Phase III clinical study, JSKN003-301, is a randomized, controlled, open-label, multicenter trial aimed at evaluating the efficacy and safety of JSKN003 compared to emtansine (T-DM1) in the treatment of patients with HER2-positive, unresectable locally advanced or metastatic breast cancer who have previously received trastuzumab or taxane-based therapies. The primary endpoint of the study is progression-free survival (PFS) as assessed by the Blinded Independent Review Committee (BIRC).

The market for HER2-positive breast cancer treatments is substantial, with an estimated 20% to 25% of all breast cancer cases in China falling into this category. Existing treatments for HER2-positive breast cancer include trastuzumab (Herceptin), pertuzumab (Perjeta), and trastuzumab emtansine (T-DM1, Kadcyla). However, JSKN003's unique mechanism of action as a bispecific ADC may offer advantages in terms of efficacy and safety, potentially differentiating it from these competitors.

In conclusion, the first patient dosed in the Phase III clinical study of JSKN003 for HER2-positive breast cancer marks a significant step forward in the development of this novel therapy. With its promising early-stage results and unique mechanism of action, JSKN003 has the potential to become a valuable addition to the treatment landscape for HER2-positive breast cancer. As the study progresses, investors and the broader healthcare community will eagerly await the results, which could have a significant impact on the future of breast cancer treatment.