Pharmaceutical giant Sanofi (SNY 2.71%) and biotech Regeneron (REGN 0.84%) have announced the start of two late-stage clinical trials for their experimental rheumatoid arthritis drug sarilumab. This antibody is being tested in combination with methotrexate, a drug often used for the treatment of rheumatoid arthritis, and will be compared to Amgen (AMGN -0.05%) and Pfizer's (PFE 1.25%) Enbrel. In the following video, health-care analyst Max Macaluso discusses these clinical trials and how this drug could compete in the rheumatoid arthritis market.