Infection risk similar for TNF inhibitors plus methotrexate, triple therapy in RA
Among patients with rheumatoid arthritis, there is no substantial difference in the risk for any serious infection, including bacterial infection or herpes zoster, with TNF inhibitors plus methotrexate compared with triple therapy, according to data published in Arthritis Care & Research.
“The use of triple therapy is very limited in the United States, even in the regions with a higher proportion of triple therapy initiation,” Seoyoung C. Kim, MD, ScD, MSCE, of Harvard Medical School and Brigham and Women's Hospital, told Healio Rheumatology. “In most states, the percentage of triple therapy initiation was less than 5% in patients who needed more than just methotrexate.”
To compare the risk for serious infection between treatment with a TNF inhibitor plus methotrexate vs. triple therapy — a combination of methotrexate, hydrochloroquine and sulfasalazine — in patients with RA, Kim and colleagues conducted a cohort study using the Truven MarketScan database. Focusing on patients with RA in the time period from Jan. 1, 2006, to June 30, 2015, the researchers identified 45,208 patients who initiated TNF inhibitors plus methotrexate, and 1,387 who initiated triple therapy.
The primary outcome was any serious infection, including bacterial and opportunistic infections or herpes zoster, resulting in hospitalization. Secondary outcomes included individual components of the composite endpoint. The researchers used propensity score-based fine stratification and weighting to adjust for baseline confounding.
According to the researchers, the incidence rate of any serious infection per 100 person-years was 2.46 among patients treated with a TNF inhibitor plus methotrexate, compared with 2.03 for triple therapy. Following propensity score stratification, HR for any serious infection comparing TNF inhibitors plus methotrexate vs. triple therapy was 1.23 (95% CI, 0.871.74). Regarding secondary outcomes, following propensity score stratification, hazard ratios were 1.41 (95% CI, 0.852.34) for bacterial infection and 0.8 (95% CI, 0.551.18) for herpes zoster.
“Using a rigorous propensity score and fine stratification method to control for baseline confounding, we found no substantially different risk of serious infection between TNF inhibitor initiators and triple therapy initiators,” Kim said. “We noted a numerically greater risk of bacterial infection associated with TNF inhibitor initiation and a numerically lower risk of herpes zoster associated with TNF inhibitor vs. triple therapy. However, due to the small size of triple therapy group — despite using the very large dataset — our results were somewhat imprecise.”
She added, “Clinically, our results may help clinicians and patients choose a treatment after methotrexate failure, as our study suggests that infection risk is not too different between the two treatment choices.” – by Jason Laday
Disclosure: Kim reports research grants to the Brigham and Women’s Hospital from AbbVie, Bristol-Myers Squibb Pfizer and Roche. Please see the full study for additional authors’ disclosures.