A new biotechnology company emerged Monday with substantial Series A funding of $187 million and innovative technology for developing advanced antibody-drug conjugates (ADCs) capable of delivering multiple cancer-fighting agents simultaneously.
The newly formed Callio Therapeutics, which maintains dual
headquarters in Seattle and Singapore, has secured exclusive licensing rights to utilize specialized ADC technology from Singapore-based Hummingbird Bioscience for oncology applications. The licensing agreement provides Hummingbird with an equity stake in Callio and the potential for additional payments based on achievement of certain milestones.
The startup’s launch comes amid growing industry enthusiasm for ADC technology, which has seen increased attention following recent clinical successes. ADCs function by combining toxic compounds with targeting antibodies, allowing for more precise delivery of cancer treatments while minimizing damage to healthy tissues.
Callio’s leading drug candidate targets HER2, a protein commonly associated with certain cancers. Unlike existing HER2-targeted ADCs such as Enhertu – a successful treatment jointly developed by AstraZeneca and Daiichi Sankyo – Callio’s approach incorporates multiple payload molecules. This multi-payload strategy is designed to enhance the treatment’s effectiveness and potentially overcome resistance that can develop to single-payload ADCs that utilize topoisomerase 1 inhibitors, such as Enhertu.
The company has also obtained rights to a second ADC from Hummingbird, though the target for this compound remains undisclosed.
“By enabling targeted delivery of rational drug combinations to cancer cells, multi-payload ADCs may significantly improve treatment efficacy,” said Piers Ingram, who serves as both CEO and co-founder of Callio Therapeutics, in an official statement.
The substantial Series A funding round was spearheaded by Frazier Life Sciences, which launched the company, with participation from nine additional investors including Jeito Capital, Novo Holdings, and Omega Funds.
The leadership team at Callio brings together experienced executives from both Hummingbird and the broader ADC field. Ingram, who also co-founded and leads Hummingbird Bioscience, is joined by fellow Hummingbird executives Jerome Boyd-Kirkup and Angele Maki.
Additionally, the company has recruited Naomi Hunder, who previously served as chief medical officer at ProfoundBio – an ADC-focused startup that was acquired by Genmab in 2024.
This development occurs during a period of renewed interest in ADC technology within the pharmaceutical industry. Recent years have seen several technical breakthroughs and successful clinical trials that have demonstrated the potential of ADCs to improve upon traditional chemotherapy approaches. The field has gained particular attention following the success of Enhertu, which has transformed treatment protocols for certain breast cancers and generated billions in revenue for its developers.
The company’s multi-payload technology represents a potential evolution in ADC development, aiming to address limitations of current generation ADCs while potentially offering more robust treatment options for cancer patients. By incorporating multiple therapeutic agents into a single ADC, Callio’s approach could provide new solutions for dealing with treatment resistance and improving overall efficacy.
The substantial funding secured by Callio reflects growing investor confidence in next-generation ADC technologies and their potential to advance cancer treatment options. As the company moves forward with its development programs, it joins a growing field of biotechnology firms working to expand the capabilities and applications of ADC technology in oncology.