Janssen, GSK’s RA treatment sirukumab demonstrates mixed results against AbbVie’s Humira

Sirukumab is being co-developed by Janssen Biologics (Ireland) and GSK.

The companies unveiled results from two pivotal phase 3 studies assessing subcutaneous (SC) sirukumab, a human anti-interleukin (IL)-6 monoclonal antibody in development to treat adults with moderately to severely active RA.

The Phase 3 SIRROUND-H study included 559 biologic-naïve patients with moderately to severely active RA who were intolerant to methotrexate (MTX), considered inappropriate for MTX treatment for safety reasons or were inadequate responders to MTX.

Patients receiving sirukumab 50 mg every four weeks (q4w) and those receiving sirukumab 100 mg every two weeks (q2w) experienced significant mean changes from baseline in DAS28 at week 24 of -2.58 and -2.96, respectively, one of two co-primary endpoints of the study, compared with a mean change of -2.19 in patients receiving adalimumab 40 mg q2w (P = 0.013 and P < 0.001, respectively).

The phase 3 SIRROUND-T trial is a randomized, double-blind, placebo-controlled study that included 878 patients refractory to anti-TNF therapy, about 40% of whom had prior exposure to non-TNF biologic therapies.

In SIRROUND-T, among patients refractory/intolerant to anti-TNF treatments, 40% of patients receiving sirukumab 50 mg q4w and 45% of patients receiving sirukumab 100 mg q2w achieved the study’s primary endpoint, at least a 20% improvement in signs and symptoms (ACR20) at week 16, compared with 24% of patients receiving placebo (P ≤ 0.001).

Around 40% of patients in the study had prior exposure to non-TNF biologic therapies.

Janssen Research & Development head of immunology development Newman Yeilding said: “We believe the sirukumab data generated to date show the potential of this IL-6-targeted therapy to benefit adults living with moderately to severely active RA in the future, and we look forward to continuing to work with global health authorities on the applications that have been submitted.”