The deal includes initial payments of USD 785 million and gives J&J an exclusive option to acquire the company for USD 2.58 billion.

The collaboration will initially focus on Sail’s lead autoimmune disease program, while also exploring additional programs built on the company’s eRNA and targeted nanoparticle platform. Sail says its approach is designed to reprogram immune cells directly inside the body, with the goal of making CAR-T therapy more scalable than traditional ex vivo cell therapies.

“Unlike traditional cell therapies, Sail’s lead program and platform are designed to reprogram a patient’s immune cells directly within the body,” the company said. Johnson & Johnson said the partnership could help deliver therapies with durable, disease-modifying potential.

Sail, a Flagship Pioneering company, is building RNA medicines intended to instruct therapeutic activity inside selected cells. The company’s in vivo CAR-T platform is being developed for autoimmune and other immune-mediated diseases.