Fusion Pharmaceuticals has nominated the first targeted alpha therapy (TAT) candidate under its partnership agreement with AstraZeneca to commence Phase I clinical trials.

The companies will co-develop the new TAT through a Phase I trial.

The new TAT leverages the Fast-Clear linker technology of Fusion to radiolabel an AstraZeneca-owned bispecific antibody with actinium-225 alpha-emitting isotope.

According to the prior partnership agreement, Fusion will handle the preclinical development through first-in-human trials while AstraZeneca will oversee the following clinical development. 

Fusion and AstraZeneca will split clinical development expenditures equally, with investigational new drug (IND)-enabling studies underway.

Fusion Pharmaceuticals CEO John Valliant said: “Fusion is at the forefront developing a new wave of cancer therapies using alpha-emitting medical isotopes and various targeting vehicles. 

“One of the pillars of our platform is to create next-generation immunoconjugates, and we are excited to be working with AstraZeneca to pursue a novel radioimmunoconjugate for oncology. 

“We had strong alignment among our joint development committee to move this novel TAT forward into a planned Phase I study and we look forward to sharing more information as we approach the investigational new drug application (IND) filing.”

Fusion and AstraZeneca currently have a partnership for the co-development of up to three new TATs.

Up to five combination programmes would also be explored between TATs of Fusion and AstraZeneca’s DNA damage response inhibitors and immuno-oncology agents.

A lead programme of Fusion, FPI-1434 acts on the insulin-like growth factor 1 receptor and is presently being analysed in a Phase I trial. 

The company’s pipeline comprises FPI-1966 and FPI-2059, the latter being a small molecule acquired by Fusion from Ipsen.

Last December, AstraZeneca and Ionis Pharmaceuticals entered an agreement for the development and commercialisation of eplontersen.