Daiichi Sankyo Launches Phase 1 Trial for New Cancer Treatment

Daiichi Sankyo has initiated a phase 1 clinical trial for its new antibody-drug conjugate (ADC), designated DS3610, aimed at treating patients with advanced, metastatic, or unresectable solid tumours. This trial marks a significant step in the company’s ongoing efforts to develop innovative cancer therapies where standard treatments have failed. The trial will enroll approximately 70 patients across sites in Asia, Europe, and North America.

The STING (stimulator of interferon genes) pathway has garnered attention as a promising target in oncology, with several pharmaceutical companies previously attempting to develop therapies that activate this protein to enhance the body’s immune response against cancer cells. Despite early enthusiasm, many efforts have been hampered by safety concerns and unsatisfactory clinical results.

MSD, known as Merck & Co in the US and Canada, was one of the frontrunners with its candidate, ulevostinag (MK-1454). However, the company halted the programme in 2021 after it failed to demonstrate efficacy as a standalone treatment and in combination with its PD-1 inhibitor Keytruda (pembrolizumab). Similarly, Novartis/Aduro abandoned its drug ADU-S100 in 2019 due to inadequate clinical outcomes, joining other companies like Pfizer and Takeda that have faced setbacks in their STING-related projects.

Despite these challenges, interest in the STING pathway persists. Companies such as Boehringer Ingelheim, Bristol Myers Squibb, GSK, and Takeda are actively pursuing early-stage development programs targeting STING.

Daiichi Sankyo’s DS3610 features a monoclonal antibody with innovative modifications to its Fc region, although the specific cellular target has yet to be disclosed. The ADC carries a STING agonist as its payload, aiming to combine precise tumour targeting with immunotherapy. “By combining precise tumour targeting with an immunotherapy payload, Daiichi Sankyo is exploring a new way to harness the body’s own defences to attack cancer,” stated Ken Takeshita, the company’s head of R&D. He emphasized that the start of this first-in-human trial represents a crucial advancement in Daiichi Sankyo’s ADC portfolio and reinforces the company’s commitment to developing transformative cancer therapies.

The initiation of this trial increases the number of ADCs in clinical development at Daiichi Sankyo to seven. This portfolio includes the HER2-directed Enhertu (trastuzumab deruxtecan) and the TROP2-targeting Datroway (datopotamab deruxtecan), both of which are currently available on the market in partnership with AstraZeneca. The company is also advancing several other candidates, including those targeting B7-H3 (ifinatamab deruxtecan), CDH6 (raludotatug deruxtecan), and HER3 (patritumab deruxtecan), all partnered with MSD. Additionally, an in-house candidate, DS-3939, targets TA-MUC1.

As Daiichi Sankyo embarks on this new clinical trial, the industry will be watching closely to see if DS3610 can overcome the hurdles faced by previous STING agonists and contribute to the evolving landscape of cancer treatment.