Washington, June 14 : When treated with Tocilizumab plus methotrexate, patients with moderate to severe rheumatoid arthritis (RA), who did not show a satisfactory response to anti-tumour necrosis factor (anti-TNF) therapy, displayed significant clinical improvements in efficacy and safety, a new study has revealed.
This study, called the RADIATE study, was a randomised, double-blind study of 499 patients with moderate to severe RA, of which 12-18 percent patients had 3 or more prior anti-TNF failures.
The study underlined that Tocilizumab, an anti-interleukin (IL)-6 receptor monoclonal antibody, was quite an effective treatment, irrespective of the number of, or the most recently-failed anti-TNF treatments.
It was found that after 24 weeks of treatment, 30.1 percent of patients receiving 8mg/kg tocilizumab plus methotrexate, who had active RA despite prior anti-TNF therapy, achieved DAS28 (a measure of disease remission), as compared to only 1.6 percent in the placebo arm.
50 percent of patients on the same regime achieved the study's primary endpoint of ACR20 (a 20 percent improvement in symptoms) compared to 10 percent of patients in the placebo arm.
Those who received 4mg/kg tocilizumab plus methotrexate experienced similar, though slightly lower results with 7.6percent achieving DAS28 and 30.4percent achieving ACR20.
"Although anti-TNF therapies for RA are well-established, a substantial number of patients are inadequately controlled by these treatments, or become refractory to them. The results of this trial suggest that tocilizumab offers a much needed and effective option for such patients," said professor Paul Emery of Leeds Teaching Hospital Trust / Leeds University, UK, lead investigator in the trial.
The team also noted that a low proportion of the patients in the 8mg/kg tocilizumab group experienced serious adverse effects (6percent) or serious infections (5percent) during the trial.
But, there wasn't any difference in safety or tolerability based on prior anti-TNF treatment.
The RADIATE study was presented at EULAR 2008, the Annual Congress of the European League Against Rheumatism in Paris, France.