Comparison of ixekizumab with etanercept or placebo in moderate-to-severe psoriasis (UNCOVER-2 and UNCOVER-3): results from two phase 3 randomised trials

Summary Background Ixekizumab is a humanised monoclonal antibody against the proinflammatory cytokine interleukin 17A. We report two studies of ixekizumab compared with placebo or etanercept to assess the safety and efficacy of specifically targeting interleukin 17A in patients with widespread moderate-to-severe psoriasis. Methods In two prospective, double-blind, multicentre, phase 3 studies (UNCOVER-2 and UNCOVER-3), eligible patients were aged 18 years or older, had a confirmed diagnosis of chronic plaque psoriasis at least 6 months before baseline (randomisation), 10% or greater body-surface area involvement at both screening and baseline visits, at least a moderate clinical severity as measured by a static physician global assessment (sPGA) score of 3 or more, and a psoriasis area and severity index (PASI) score of 12. Participants were randomly assigned (1:2:2:2) by computer-generated random sequence with an interactive voice response system to receive subcutaneous placebo, etanercept (50 mg twice weekly), or one injection of 80 mg ixekizumab every 2 weeks, or every 4 weeks after a 160 mg starting dose. Blinding was maintained with a double-dummy design. Coprimary efficacy endpoints were proportions of patients achieving sPGA score 0 or 1 and 75% or greater improvement in PASI at week 12. Analysis was by intention to treat. These trials are registered with ClinicalTrials.gov , numbers NCT01597245 and NCT01646177. Findings Between May 30, 2012, and Dec 30, 2013, 1224 patients in UNCOVER-2 were randomly assigned to receive subcutaneous placebo (n=168), etanercept (n=358), or ixekizumab every 2 weeks (n=351) or every 4 weeks (n=347); between Aug 11, 2012, and Feb 27, 2014, 1346 patients in UNCOVER-3 were randomly assigned to receive placebo (n=193), etanercept (n=382), ixekizumab every 2 weeks (n=385), or ixekizumab every 4 weeks (n=386). At week 12, both primary endpoints were met in both studies. For UNCOVER-2 and UNCOVER-3 respectively, in the ixekizumab every 2 weeks group, PASI 75 was achieved by 315 (response rate 89·7%; [effect size 87·4% (97·5% CI 82·9–91·8) vs placebo; 48·1% (41·2–55·0) vs etanercept]) and 336 (87·3%; [80·0% (74·4–85·7) vs placebo; 33·9% (27·0–40·7) vs etanercept]) patients; in the ixekizumab every 4 weeks group, by 269 (77·5%; [75·1% (69·5–80·8) vs placebo; 35·9% (28·2–43·6) vs etanercept]) and 325 (84·2%; [76·9% (71·0–82·8) vs placebo; 30·8% (23·7–37·9) vs etanercept]) patients; in the placebo group, by four (2·4%) and 14 (7·