On June 26, 2026, the Center for Drug Evaluation (CDE) of China’s National Medical Products Administration (NMPA) announced that AMT‑676, a CDH17‑targeted antibody‑drug conjugate (ADC) developed by Multitude Therapeutics, has been granted Breakthrough Therapy Designation. The designation is indicated for the treatment of patients with advanced microsatellite‑stable/proficient mismatch repair (MSS/pMMR) colorectal cancer (CRC) who have progressed two or more prior lines of standard therapy.
AMT-676 is a potential first-in-class CDH17-directed ADC. Its first-in-human clinical trial is currently ongoing in Australia, the United States, and China. As of May 22, 2026, a total of 246 patients had been enrolled. Among efficacy-evaluable CRC patients treated at doses ranging from 7.2 to 12 mg/kg, AMT-676 achieved an overall response rate (ORR) of 20% (20/100) and a disease control rate (DCR) of 91%. In the 8 mg/kg cohort, the ORR reached 26% (12/47). AMT-676 has also demonstrated a favorable safety profile, with the most common treatment-related adverse events consisting of manageable hematologic and gastrointestinal toxicities.
Treatment options for patients with advanced CRC whose disease has progressed following second-line or later standard-of-care therapy remain limited, with reported ORRs of only 1%–6% and median progression-free survival (mPFS) of 2.0–5.6 months—highlighting a significant unmet medical need. The clinical data generated to date suggest that AMT-676 has the potential to offer meaningful improvements over current standards of care, providing a meaningful new treatment option with advanced CRC.
About AMT-676
AMT-676, a CDH17 ADC, is composed of a proprietary antibody with high CDH17 binding affinity, a protease-cleavable linker, and an exatecan payload (a potent and clinically validated topoisomerase-1 inhibitor). The linker is designed to complement the exatecan payload, enabling a stable and homogenous ADC. The payload is a weak substrate for BCRP/P-gp, which are drug efflux pumps that drive chemoresistance to many therapies. In preclinical data, this linker-payload has been shown to have an increased “bystander effect” compared to the equivalent of competitor ADCs*. AMT-676 has a drug-to-antibody ratio of 4. AMT-676 is being evaluated in a Phase I study in patients with CRC and other advanced solid tumors. Additional information on the Phase I (NCT06400485) trial can be found at clinicaltrials.gov.
* Weng et al., (2023) Cancer Discovery 13:950–73
About Multitude Therapeutics
Multitude Therapeutics is a clinical-stage company focused on the development of ADC therapeutics. The company employs two technology platforms: MabArray, an antibody platform for the discovery of novel cell-surface oncology targets that enables the pursuit of first-in-class targets; and PAD, a molecular design platform that serves as the backbone of the company’s R&D technology, integrating a clear understanding of tumor biology and existing treatment options with years of experience in ADC design. For identified therapeutic targets in selected indications, this platform supports the rational structural design of ADCs to achieve precise tumor targeting, potent cytotoxicity and minimal off-target effects. The combination of MabArray and PAD generates significant synergy, enabling Multitude Therapeutics to build an ADC “atlas” with the potential to treat malignancies of high unmet medical need and to achieve deeper and more durable responses. Building on these platforms, the company currently has several ADC programs in development, including three programs directed at potential first-in-class targets. Multiple ADC programs, including those against all potential novel targets, have entered clinical development and have demonstrated favorable safety and efficacy, providing initial validation of the company’s platform technologies.