Roche together with development partners Genentech and Biogen Idec announced that a phase IIb clinical study of MabThera/Rituxan (rituximab) met its primary endpoint of a greater proportion of MabThera-treated patients achieving an American College of Rheumatology (ACR) 20 response at week 24, compared to placebo, in patients who were also treated with methotrexate (MTX).

In this study, patients with moderate-to-severe rheumatoid arthritis (RA) who received two infusions of MabThera over a two-week period in combination with a stable dose of MTX experienced improved symptoms compared to patients who received placebo and MTX. The benefit in the MabThera/Rituxan treated patients was present regardless of whether additional corticosteroids were administered, a release from Roche said.

"The preliminary data from this latest study in rheumatoid arthritis confirms MabThera as a promising alternative to current therapies available to patients with RA and are consistent with earlier data showing efficacy and safety of MabThera. As we continue to explore and evaluate MabThera as a potential treatment for RA, we look forward to the results of ongoing analyses which will be presented next year," commented Dr. Eduard Holdener, head of Global Pharma Development, Roche.

This phase IIb study, DANCER (Dose-Ranging Assessment iNternational Clinical Evaluation of Rituximab in RA), was designed to evaluate the efficacy and safety of varying doses of MabThera/Rituxan in combination with methotrexate in patients with active RA who currently have an inadequate response to methotrexate. The influence of a short initial course of corticosteroids was also evaluated.

MabThera/Rituxan is a therapeutic antibody that selectively depletes B cells, which may play a key role in the inflammatory cascade of RA. B cells are an important element in the immune system, helping the body to fight off infection. However in autoimmune diseases like RA, the immune system acts abnormally leading to an attack on normal healthy tissue such as the joints. By depleting B cells, which are believed to be involved in maintaining the attack on healthy tissue, MabThera/Rituxan is thought to break the cycle of rheumatoid arthritis disease.

There is a large unmet clinical need for RA treatments. Only around 50 per cent of patients respond to and maintain treatment with DMARD (disease modifying anti-rheumatic drugs) therapy long term. Data from existing clinical trials indicates that MabThera/Rituxan is safe and well-tolerated in people with RA, the release added.