In the last decade, there have been significant advances in treating rheumatoid arthritis, especially for patients who does not respond to traditional disease-modifying anti-rheumatic drugs (DMARDs). The most important advance has been the development of a group of drugs called biologics. There are a  large number of biologics approved to treat rheumatoid arthritis. Approved biologics include: Abatacept, Abatacept, Etanercept, Golimumab , Infliximab , Rituximab , Tofacitinib . Among these tofacitinib is used to treat severe arthiritis for those patients that do not respond to methotrexate. 

This study is conducted to do a comparative analysis of the risks of malignancies following biologic DMARDs (b-DMARDs) and tofacitinib in rheumatoid arthritis (RA) by randomized clinical trials (RCTs) and long-term extension studies (LTEs). The articles are present in Medline, Embase, Cochrane Library, and the Web of Science dated from 2000 to February 2015.

Selection criteria are as follows: (1) focuses on RCTs or LTEs in RA (2) treatment with b-DMARDs or tofacitinib (3) data on malignancies (4) a minimum follow-up of 12 weeks. Data included publication details, study design, risk of bias, number and types of malignancies, patient characteristics and treatments.

Of 113 articles and one updated report of meta-analysis of overall malignancies (in RCTs) showed odds ratio (95% confidence intervals) of 1.01 (0.72, 1.42) for all TNF antagonists, 1.12 (0.33, 3.81) for abatacept, 0.54 (0.20, 1.50) for rituximab, 0.70 (0.20, 2.41) for tocilizumab, and 2.39 (0.50, 11.5) for tofacitinib. Network meta-analysis of overall malignancies showed odds ratio (95% predictive intervals) of 1.68 (0.18-5.92) for infliximab, 0.79 (0.44-1.40) for etanercept, 0.93 (0.43-2.03) for adalimumab, 0.87 (0.28-2.75) for certolizumab, 0.87 (0.39-1.95) for golimumab, 1.04 (0.32-3.32) for abatacept, 0.58 (0.21-1.56) for rituximab, 0.60 (0.16-2.28) for tocilizumab, and 1.15 (0.24-5.47) for tofacitinib. Marginal numerical differences in the incidence rate of solid and hematological malignancies and non-melanoma skin cancers appeared in LTEs.

From results it is evaluated that there is no increase in risk of malignancy when treatment of RA was done with b-DMARDs or tofacitinib in randomized clinical trials(RCT). Generalizability of the differences in the rate of specific malignancies encountered in LTEs requires continuous pharmacovigilance of real-world patients.