PT  - JOURNAL ARTICLE
AU  - Eric M.  Ruderman
TI  - Of Mice and Men: Defining the Role of Interleukin 17 in Rheumatoid Arthritis
AID  - 10.3899/jrheum.150554
DP  - 2015 Jun 01
TA  - The Journal of Rheumatology
PG  - jrheum.150554
4099  - http://www.jrheum.org/content/early/2015/05/25/jrheum.150554.short
4100  - http://www.jrheum.org/content/early/2015/05/25/jrheum.150554.full
AB  - In a recent issue of The Journal, Pavelka and colleagues reported on a negative study of brodalumab, the interleukin 17 (IL-17) inhibitor, in rheumatoid arthritis (RA). In addition to the authors’ conclusion that there is no reason to pursue further evaluation of the molecule, an antibody against the IL-17 receptor A (IL-17RA), in this disease, there are a number of other important lessons to be learned from this publication. Combined with previously published data for secukinumab and ixekizumab, 2 anti-IL-17A antibodies, the results of this study strongly suggest that the IL-17 pathway is not an appropriate target in RA. This conclusion comes despite both animal data suggesting potential benefit and clinical evidence that IL-17 inhibition is effective in psoriatic arthritis (PsA). The latter observation is instructive, and may provide a clue to important pathogenic differences between 2 outwardly similar forms of inflammatory arthritis.