Genentech/Biogen's ocrelizumab meets primary endpoints in first Ph III Trial in RA

US biotechnology major Genentech, a wholly owned subsidiary of Switzerland's Roche, and Biogen Idec have revealed results form a Phase III study (STAGE) of the investigational humanized anti-CD20 monoclonal antibody ocrelizumab given in combination with methotrexate (MTX) met its primary endpoint of improving signs and symptoms (as measured by American College of Rheumatology or ACR20 response) in rheumatoid arthritis (RA) patients who had an inadequate response to MTX at both 24 and 48 weeks. Genentech and Biogen Idec continue to analyze the study results and plan to submit the data for presentation at an upcoming medical meeting.

'These results are significant because they are the first data from a large Phase III trial to show that a humanized antibody targeted at B-cells improves the signs and symptoms of rheumatoid arthritis,' said Hal Barron, executive vice president, Global Development and chief medical officer at Genentech. 'These results build on earlier findings from our broad clinical program aimed at developing medicines to help people living with rheumatoid arthritis.'

'While these latest data will raise confidence in ocrelizumab's clinical progress, Genentech has yet to provide evidence that this follow-on CD20 is sufficiently differentiated from the company's previous offering, rituximab, comment analysts at market research group Datamonitor. Although a humanized antibody should theoretically provide advantages over a chimeric monoclonal antibody, this has yet to be demonstrated for ocrelizumab. Similarly, ocrelizumab and Arzerra are not yet differentiated clearly enough. Nevertheless, should physicians be convinced to opt for the newer drug over Rituxan, Datamonitor expects that ocrelizumab could generate sales of $425 million for rheumatoid arthritis in the seven major markets in 2018.