BARCELONA — Cumulative improvements were seen in rheumatoid arthritis patients treated with abatacept, Dr. Maxime Dougados reported at the annual European Congress of Rheumatology.
The Abatacept in Inadequate responders to Methotrexate (AIM) trial was 1 year, double blind, and placebo controlled. RA patients, mean age 51 years, were randomized to intravenous abatacept (10 mg/kg) or placebo on days 1, 15, and 29 and every 4 weeks after, plus background methotrexate. In a subsequent open-label phase, all patients received abatacept for up to 2 years. Among the 652 patients in the first phase, 385 (89%) in the abatacept group completed the 1-year treatment, versus 162 (74%) in the placebo group. Moreover, a significantly greater proportion of abatacept patients achieved an American College of Rheumatology (ACR) 20, 50, or 70 at 1 year than patients on placebo (Ann. Intern. Med. 2006;144:865-76).
Of those who had an ACR 20 at 6 months, 43% of abatacept patients had at least an ACR 50 at 1 year, versus 14% of placebo patients. The proportion who had an ACR 70 at 1 year was 21% in the abatacept group and 2% in the placebo group. A total of 15% of abatacept patients who achieved an ACR 20 at 6 months lost this response at 1 year, as did 37% of placebo patients. Significantly more patients on abatacept also achieved a low disease activity score (LDAS), of 3.2 or less. A total of 43% of abatacept patients achieved this, versus 10% of placebo patients. Of those who had an LDAS at 6 months, 36% of abatacept-treated patients and no placebo-treated patients achieved a DAS28 remission at 1 year. Thirty-two percent of abatacept patients had an LDAS at 6 months but not 1 year, versus 57% of placebo patients.
AIM was sponsored by Bristol-Myers Squibb.