However, in the study, patients who felt that they needed more medication could choose to step up to a weekly subcutaneous injection, but only 10 in the Humira group and 7 in the Actemra group (who were really receiving a placebo instead of the active drug) chose to do so.

Stanley Cohen, MD, medical director of the rheumatology program at Presbyterian Hospital Dallas, Texas, says the criticism is unwarranted because the dose of adalimumab used in the study – 40 mg every two weeks – is the dose typically used in the United States. Dr. Cohen was not involved in the study.

Dr. Cohen says, while interesting, the new results are unlikely to persuade more U.S. doctors to prescribe tocilizumab instead of adalimumab for these patients. He notes that guidelines from the American College of Rheumatology, or ACR, recommend that (in most cases) a patient should be started on a TNF-blocker, like adalimumab, before being moved to another type of biologic, such as an IL-6 inhibitor, like tocilizumab.

Additionally, the indication tocilizumab received when it got FDA approval is for people who have failed one or more TNF-blockers. Roche says it hopes to obtain FDA approval to market tocilizumab as a first-line treatment for RA patients.

At this point, Dr. Cohen says, the question of how to help methotrexate-intolerant patients who have tried and failed to be helped by a TNF blocker – a class that includes etanercept (Enbrel) and infliximab (Remicade) as well as adalimumab – remains open. Should the doctor try another TNF blocker, or the IL-6 inhibitor tocilizumab, or a different type of biologic drug like abatacept (Orencia), which works via an altogether different mechanism?

They all offer similar degrees of relief, he says, so quality of life issues come into play. For example, adalimumab is a shot you can give yourself at home every other week. Tocilizumab requires monthly trips to the doctor's office for an infusion, which can be problematic for people in rural areas or for those who can't take time off work.

Additionally, some patients respond better to one drug than another for reasons that are not clear. "What we really need," says Dr. Cohen, "is to find biomarkers so we can give simple blood tests to identify which patents will benefit from which drug."

Dr. Cohen also said longer follow-up is needed as six months is not really long enough to demonstrate superiority over time. Future trials should also test different combinations of drugs, as multi-pronged attacks on the out-of-whack immune system may prove most effective, he says.