Chinese biopharmaceutical company Akeso Inc (HK:9926) announced on Tuesday that it has received approval from the Center for Drug Evaluation (CDE) of China's National Medical Products Administration (NMPA) to commence Phase II clinical trials for AK146D1, a first-in-class Trop2 /Nectin4 bispecific antibody-drug conjugate (ADC), and AK138D1, an innovative HER3-targeting ADC.

The studies will evaluate these two novel ADC candidates in combination with Akeso's immuno-oncology (IO) 2.0 bispecific antibodies, cadonilimab (PD-1/CTLA-4) and ivonescimab (PD-1/VEGF), as well as other proprietary high-potential anti-tumour assets, including AK117 (anti-CD47 monoclonal antibody) and AK109 (anti-VEGF monoclonal antibody), across a spectrum of advanced solid tumours.

Akeso said that this milestone marks a strategic acceleration of its proprietary 'IO 2.0 + ADC 2.0' combination platform into mid-stage clinical development.

The Phase II studies will leverage cadonilimab and ivonescimab as foundational backbone therapies, capitalising on their validated clinical profiles in checkpoint blockades and dual VEGF/PD-1 inhibition. The regimens centre on Akeso's internally discovered next-generation ADCs while exploring synergies with the company's broader internal portfolio.

AK146D1 is a first-in-class bispecific ADC engineered to simultaneously target Trop2 and Nectin4, antigens that are frequently co-expressed in epithelial-derived malignancies such as lung, breast, and bladder cancers. AK138D1 is a next-generation ADC targeting HER3, a receptor associated with tumour progression and resistance to established EGFR and HER2 treatments in various malignancies, including ovarian, colorectal, melanoma, and prostate cancers.