Astellas and Audax sign a potential $1.34 billion DAX-044 deal, advancing an investigational IL-12 antibody-cytokine fusion towards Phase I testing.
Written By: Umesh Hanumante, PharmD
Reviewed By: Pharmacally Editorial Team
Astellas Pharma and Audax Biosciences have entered into an exclusive option and licence agreement for DAX-044, an investigational antibody-cytokine fusion designed to direct interleukin-12 (IL-12) activity towards solid tumours. The agreement has a total potential value of up to US$1.34 billion, excluding royalties, and grants Astellas the exclusive option to obtain worldwide rights to develop, manufacture and commercialise the candidate.
Audax will fund and continue development of DAX-044 towards a Phase I clinical study, expected to begin in 2027. If Astellas exercises its option, it will assume sole responsibility for global development, manufacturing and commercialisation. Audax will retain the option to co-fund and co-promote DAX-044 in Australia and New Zealand.
A Targeted Approach to IL-12 Immunotherapy
Immuno-oncology aims to stimulate the immune system to recognise and attack cancer cells. However, therapies based on IL-12 have faced toxicity challenges associated with systemic exposure, limiting their therapeutic application.
IL-12 is an immune-signalling protein that activates immune cells involved in anti-tumour responses. DAX-044 uses Audax’s AVIKINE® technology and is designed to concentrate IL-12 activity within the tumour microenvironment, with the aim of stimulating anti-cancer activity while limiting systemic exposure.
According to the companies, preclinical studies indicate a potential best-in-class therapeutic index for DAX-044 as an IL-12-based agent. The candidate remains in investigational new drug application/clinical trial notification (IND/CTN)-enabling development, and its safety, efficacy and potential advantages have yet to be established in humans.
Understanding the Agreement
The agreement includes an upfront payment and a potential future option-exercise payment totalling US$285 million. Audax may also receive up to US$1.05 billion in development and commercial milestone payments, plus tiered double-digit royalties on worldwide net sales if DAX-044 is approved.
The US$1.34 billion headline value represents maximum potential payments, excluding royalties, rather than guaranteed revenue. Future payments will depend on development progress, milestone achievements and contractual conditions.
If Astellas exercises its option, it will assume responsibility for global development, manufacturing and commercialisation. Audax will have an option to co-fund and co-promote DAX-044 in Australia and New Zealand. Option exercise is subject to customary conditions, including applicable antitrust clearances.
Clinical Interpretation
DAX-044 is designed to address a central challenge in IL-12-based immunotherapy: stimulating anti-tumour immune activity while limiting toxicity associated with systemic exposure. Whether its targeted design can achieve this balance in humans remains uncertain.
The planned Phase I study, expected to begin in 2027, will provide the first clinical assessment of the candidate’s safety, tolerability, dosing and early biological activity. Until human data are available, the reported therapeutic potential remains based on preclinical findings.
For Astellas, the option agreement provides a potential route to worldwide rights while Audax advances DAX-044 towards clinical testing. The programme’s longer-term value will depend on its clinical results and whether the candidate progresses through subsequent development and regulatory evaluation.
Reference
Astellas and Audax Biosciences Enter Exclusive Option and License Agreement for DAX-044, Astellas Pharma Inc 28 October 2026
About the Writer
Umesh Hanumante (M.Pharm) (LinkedIn) is a pharmacy professional and healthcare writer with a background in Regulatory Affairs, pharmaceutical innovation, and clinical research. He has around two years of industry experience as an Executive PMT at Troikaa Pharmaceuticals Ltd and qualified GPAT 2024. His areas of interest include regulatory compliance, dossier preparation, clinical trials, emerging therapies, and advancements in the global pharmaceutical and healthcare sector.