Abatacept, anti-TNFs prove comparable after prior anti-TNFs

Outcomes in patients with rheumatoid arthritis and prior exposure to an anti–tumor necrosis factor drug who switched to a new anti-TNF drug were similar to those in patients with prior anti-TNF exposure who initiated abatacept in a comparative effectiveness trial.

The mean changes in Clinical Disease Activity Index (CDAI) scores; modified American College of Rheumatology (mACR) 20, 50, and 70 responses; modified Health Assessment Questionnaire (mHAQ) scores; and remission rates on the CDAI all were similar at 6 and 12 months after treatment initiation in propensity score-matched groups of patients from the large observational cohort study who either switched anti-TNF drugs or initiated abatacept after exposure to an anti-TNF drug, Dr. Leslie R. Harrold of the University of Massachusetts Medical School, Worcester, and her colleagues reported.

For example, at 6 months in 746 anti-TNF users and 431 abatacept users and at 12 months in 493 anti-TNF users and 311 abatacept users, the mean differences in CDAI scores were 0.46 and –1.64, respectively, after adjustment for number of prior anti-TNF medications, baseline disease activity, rheumatoid arthritis disease severity, and concomitant medications. Also, mACR20 responses at 6 months were 28.2% vs. 31.7%.

At 12 months, 35%-37% of patients in the groups achieved mACR20, 20%-22% achieved mACR50, and 10%-12% achieved mACR70. A meaningful change in mHAQ score was achieved by 30%-33% of patients at 6 months and 29%-30% at 12 months. CDAI remission rates were 9%-10% at 6 months and 12%-14% at 12 months, the investigators said (Ann. Rheum. Dis. 2013 Dec. 2 [doi:10.1136/annrheumdis-2013-203936]).

Patients were Consortium of Rheumatology Researchers of North American (CORRONA) registry participants with exposure to one or more anti-TNF agents but no prior use of non-anti-TNF biologics, according to data from Feb. 1, 2000, to Aug. 1, 2011, the investigators said.

The findings of the current analysis, which is among the first to examine comparative effectiveness of abatacept and anti-TNF agents in those with prior anti-TNF agent exposures, suggest that "just changing the mechanism of action may not be enough to improve disease activity," Dr. Harrold and her associates wrote.

"When discussing next therapeutic interventions in those not responding or unable to take their current anti-TNF agents, these results can potentially contribute to the discussion as patients weigh other factors such as potential adverse events associated with the different agents, out-of pocket costs, and medication route of administration," they said.

Additional comparative effectiveness studies are needed to evaluate the potential benefits of switching to a different non-TNF biologic versus anti-TNF intra-class switching in patients who have an inadequate response to an anti-TNF, they concluded.

CORRONA has received support from Abbott, Amgen, Astra-Zeneca, Genentech, Janssen (Centocor), Eli Lilly, and Pfizer through contracted subscriptions to the database. The investigators reported ties with CORRONA, AbbVie, Amgen, Bristol-Myers Squibb, Genentech, Lilly, Pfizer, UCB, Roche, Janssen, Crescendo, UpToDate, Novartis, the National Institutes of Health, the Agency for Healthcare Research and Quality, the Arthritis Foundation, and/or the Arthritis National Research Foundation.