Research from The Parker Institute now published in The Lancet

Biological agents are causally associated with an increase in serious infections in patients with rheumatoid arthritis; Standard-dose and high-dose biological drugs increase the risk, unlike low-dose biological drugs which do not.

Prior to this new cutting edge meta-analysis, serious infections was an unsolved major concern for patients considering treatments for rheumatoid arthritis as the evidence was inconsistent as to whether biological drugs are associated with an increased risk.

Musculoskeletal Statistics Unit, The Parker Institute has as part a global network of researchers from the Cochrane Collaboration, now published a systematic review and meta-analysis in the prominent high impact journal The Lancet. Based on 106 trials, that reported serious infections and included patients with rheumatoid arthritis who received biological drugs, we now know that biologics are causally associated with an increase risk in serious infections.

Compared with traditional DMARDs, standard-dose biological drugs (OR 1.31, 95% CI: 1.09–1.58) and high-dose biological drugs (1.90, 1.50–2.39) were associated with an increased risk of serious infections, although low-dose biological drugs (0.93, 0.65–1.33) were not. The analysis show that the absolute increase in the number of serious infections per 1000 patients treated each year ranged from six for standard-dose biological drugs to 55 for combination biological therapy, compared with traditional DMARDs.

The authors conclude that these findings are important in terms of shared decision-making; clinicians should discuss the balance between benefit and harm with the individual patient before starting biological treatment for rheumatoid arthritis.


The article was published in the Lancet on May 12.

Risk of serious infection in biological treatment of patients with rheumatoid arthritis: a systematic review and meta-analysis. Singh JA, Cameron C, Noorbaloochi S, Cullis T, Tucker M, Christensen R, Ghogomu ET, Coyle D, Clifford T, Tugwell P, Wells GA. Lancet. 2015 May 11. pii: S0140-6736(14)61704-9. doi: 10.1016/S0140-6736(14)61704-9. [Epub ahead of print] PMID: 25975452