Rallybio revs up antibody discovery activities with risk-sharing AbCellera pact

Rallybio has become the latest company to hitch its antibody drug development efforts to AbCellera. The partners will co-develop up to five rare disease therapeutic targets in a risk-sharing pact, starting with a metabolic disease program.

AbCellera, a biotech perhaps best known for its work on Eli Lilly’s COVID-19 antibodies, has signed up a string of drug developers as partners in recent years on the strength of its discovery platform. Rallybio has now added its name to that list by forming a multiyear, multitarget collaboration that could provide a stream of new programs for its pipeline.

Rallybio CEO Martin Mackay, Ph.D., said the partnership covers rare hematology, immuno-inflammation, maternal fetal health and metabolic disorders, with the latter therapeutic area topping the companies’ list of priorities. The partners will jointly choose targets.

That meritocratic approach to target selection reflects the fact both companies have skin in the game. Mackay framed the alliance as “a true risk and reward sharing partnership,” adding that the publicly undisclosed financial terms “reflect the contribution of each company in discovering, developing and commercializing the new antibody-based medicines that are created.”

Both parties have an option to make additional investments at progressive stages of clinical development to maintain a 50% stake in each program. If a partner opts out, their contribution will be rewarded with royalties that run from low- to mid-double-digits, depending on how deep into development it supported the program. AbCellera has an option to conduct process development and clinical manufacturing.

If the collaboration delivers candidates, they will slot into a Rallybio pipeline currently led by anti-HPA-1a antibodies that are in early-phase development as treatments for maternal fetal blood disorders. The biotech is also working on C5 inhibitors and an antibody against MTP-2.