Roche and partner Biogen Idec are suspending development of their late-stage rheumatoid arthritis treatment ocrelizumab after data pointed to serious infections that can cause death.

The firms have taken the decision following the recommendation of the independent data and safety monitoring board assessing the compound in four RA studies and two lupus trials. Roche reports that the board concluded the safety risk of ocrelizumab “outweighs the benefits observed in these specific patient populations at this time”.

The DSMB review detected “serious and opportunistic infections, some of which were fatal”. Previously, the FILM study, which evaluated ocrelizumab, a humanised anti-CD20 therapy, in methotrexate-naive RA patients was placed on clinical hold, while the BELONG study in lupus nephritis patients was previously halted due to “serious and opportunistic infection signals”.

Roche noted that ocrelizumab is still being evaluated for relapsing multiple sclerosis in an ongoing Phase II study.

The drug is a follow-up to Roche/Biogen’s MabThera/Rituxan (rituximab), which is also a part human/part mouse antibody, and many observers believed it too would become a blockbuster. However, now that fatalities have been disclosed, the likelihood of approvability has been diminished.