The race to use bispecifics to treat blood cancers is heating up, with Johnson & Johnson paying $100 million upfront to challenge Regeneron and Roche in a field that looks set to be highly competitive.
J&J is entering the space through a deal with Xencor. In return for the upfront fee and a $25 million equity investment, J&J has secured global rights to Xencor’s CD20xCD3 bispecific antibody. In a phase 1 trial in diffuse large B-cell lymphoma patients, Xencor linked the drug candidate, plamotamab, to a 28% complete response rate. More than one-third of participants in the two higher dose cohorts had complete responses.
The data set only includes 18 patients, but the early evidence of efficacy established Xencor as a rider in a race that could redefine the treatment of blood cancers. By engaging CD20 and CD3, Xencor and its rivals are aiming to turn T cells on malignant B cells and thereby drive CAR-T-like efficacy without the complexity associated with cell therapies.
Roche made the early running in the race, delivering encouraging early phase results and going on to start a phase 3 study early this year, but the first data drops suggested Regeneron may have an edge in terms of efficacy. Xencor’s efficacy results looks competitive, and, after adopting step-up dosing, its early-phase study was free from grade 3 or 4 cytokine release syndrome.
It remains unclear which of the candidates will strike the best balance between safety and efficacy, but J&J has seen enough promise in plamotamab to buy into the race. J&J will now collaborate with Xencor on further development of plamotamab and a subcutaneous version that is set to enter the clinic next year, picking up 80% of the tab along the way.
The deal, which is worth up to $1.2 billion in milestones, also covers work to develop CD28 bispecific antibody candidates against B-cell targets. Xencor struck a deal to work with J&J on CD28 bispecifics in prostate cancer late last year and is now using its platform to find candidates that conditionally activate T cells to treat certain hematological malignancies.