Abatacept for Rheumatoid Arthritis Well Tolerated After 2 Years

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Abatacept for Rheumatoid Arthritis Well Tolerated After 2 Years

http://www.medscape.com/viewarticle/547766?src=mp

Patients with rheumatoid arthritis (RA) who have been treated with abatacept

(Orencia) for 2 years or longer have no more frequent or unexpected adverse

events than they do at the onset of treatment, according to an international

team of investigators who presented their findings here at the 70th annual

meeting of the American College of Rheumatology.

" Through 2 years of treatment, abatacept demonstrated a consistent safety

profile in patients with active RA, including those with comorbidities, " said

E. Weinblatt, MD, during his presentation. " There were no new signals in

the open-label period. "

Dr. Weinblatt added, " Taken together with similar findings, the results show

that abatacept is generally safe and well tolerated and demonstrates

improvements that are maintained. " Dr. Weinblatt is a professor of medicine in

the division of rheumatology and immunology at Brigham and Women's Hospital in

Boston, Massachusetts, affiliated with Harvard Medical School.

In the double-blind phase of the Abatacept Study of Safety in Use with other

Rheumatoid arthritis therapies (ASSURE), the 1413 patients received either

abatacept or placebo on days 1, 15, and 29, and every 4 weeks thereafter. The

treated patients received a dose of approximately 10 mg/kg. All patients also

received additional treatment with one or more disease-modifying antirheumatic

drugs (DMARDs), either conventional or biologic agents.

A total of 1221 patients completed the double-blind phase and 1184 patients

entered an open-label extension, during which all patients received abatacept

once monthly at 10 mg/kg in addition to background therapies as needed. Of the

patients in the extension phase, 800 had been receiving abatacept and 384 had

been receiving placebo.

A total of 1071 patients (90.5%) completed 1 year of the long-term extension.

Most discontinuations were due to adverse events (n = 39; 3.3%), withdrawal of

consent (n = 30; 2.5%), and lack of efficacy (n = 29; 2.4%). Nonbiological

DMARDs were the most common add-on therapy; of those originally receiving

abatacept, 725 were receiving nonbiological DMARDs and 75 were receiving

biologicals. Of those originally receiving placebo, 342 were received

nonbiological DMARDs and 42 received biologicals.

During the extension period, rates of serious adverse events, serious

infections, and malignancies were distributed at similar rates to those seen in

the double-blind period, Dr. Weinblatt said. The overall pattern and intensity

of adverse events was also similar. The rate of malignant neoplasms was 1.6 per

100 patient-years during the double-blind period and 0.9 per 100 patient-years

during the open-label period. Lung cancer occurred at rates of 0.3 per 100

patient-years during the double-blind period and 0.2 per 100 patient-years

during the open-label period. As had been seen previously, abatacept-treated

patients had improvements from baseline in all patient-reported outcomes, Dr.

Weinblatt said.

" It was also interesting that, when followed for 2 years, the rate of adverse

events did not accumulate, " said Matteson, MD, in an interview. " You didn't

have more people getting sick the second year than the first year. There were no

new problems in the follow-up year. " Dr. Matteson is a professor of medicine at

Mayo Clinic College of Medicine in Rochester, Minnesota, where he is a

consultant in rheumatology.

" These are serious drugs for serious disease, and they change your immune

system, " Dr. Matteson said. " When you alter the immune system, it has

consequences, and we don't yet know if these medications put people at a higher

risk of cancer. Overall, the risk-benefit profile is good, but we need to know

what the negative consequences are too. Although the rate of adverse events is

low, they are there. "