Astellas and Audax Sign Up to $1.34B Cancer Drug Deal

Astellas Pharma and Australian biotechnology company Audax Biosciences have entered into an exclusive option and license agreement for DAX-044, an investigational cancer immunotherapy designed to help the immune system fight tumors. Announced on October 28, 2026, the agreement could be worth up to $1.34 billion, excluding royalties.

Under the agreement, Astellas will have the exclusive option to obtain worldwide rights to develop, manufacture and commercialize DAX-044. Audax will continue developing the drug candidate and plans to advance it into a Phase 1 clinical trial, which is expected to begin in 2027.

DAX-044 is an experimental treatment based on interleukin-12 (IL-12), a protein that helps activate the immune system. The drug combines IL-12 with an antibody-based targeting approach designed to direct its activity toward the tumor microenvironment, the area surrounding a tumor where cancer cells interact with immune cells and other tissues.

IL-12 has attracted interest in cancer research because of its ability to stimulate immune responses against tumors. However, earlier attempts to develop IL-12-based treatments have faced challenges, including toxicity affecting the body beyond the tumor. DAX-044 uses Audax’s AVIKINE technology and is designed to concentrate immune-activating activity within tumors while limiting these unwanted effects.

According to the companies, preclinical studies have shown that DAX-044 has the potential to offer an improved balance between effectiveness and safety. However, the treatment remains in early development, and its safety and effectiveness in humans have not yet been established.

Under the financial terms, Audax could receive up to $285 million in upfront and potential option-exercise payments. The company is also eligible for up to $1.05 billion in development and commercial milestone payments, along with tiered double-digit royalties on worldwide net sales if the treatment is approved.

If Astellas exercises its option, it will take sole responsibility for the drug’s global development, manufacturing and commercialization. Audax will retain the option to share development costs and promotional activities for DAX-044 in Australia and New Zealand.

The agreement strengthens Astellas’ immuno-oncology pipeline, a key area of its research and development strategy. The company is exploring new approaches to cancer treatment, including targeted immunotherapies that aim to stimulate the immune system against tumors.

For Audax, the partnership provides an opportunity to advance DAX-044 toward clinical testing while working with a global pharmaceutical company with experience in drug development and commercialization.

The planned Phase 1 trial will be an important next step in assessing the treatment’s safety and determining how it may perform in patients with solid tumors. Any potential future use will depend on clinical results and regulatory approval.