Efficacy and Safety of Ixekizumab in a Randomized, Double-blinded, Placebo-controlled Phase IIIb Study of Patients With Moderate-to-severe Genital Psoriasis

C. Ryan; A. Menter; L. Guenther; A. Blauvelt; R. Bissonnette; K. Meeuwis; J. Sullivan; J.C. Cather; G. Yosipovitch; A.B. Gottlieb; J.F. Merola; K. Callis Duffin; S. Fretzin; O.O. Osuntokun; R. Burge; A.N. Naegeli; F.E. Yang; C.-Y. Lin; K. Todd; A. Potts Bleakman; on behalf of the IXORA-Q Study Group


The British Journal of Dermatology. 2018;179(4):844-852. 

In This Article


Ixekizumab was superior to placebo for the treatment of moderate-to-severe GenPs during 12 weeks of treatment. Most (73%) patients receiving ixekizumab achieved complete or nearly complete resolution and 56% achieved complete resolution of GenPs. Consistently with previous clinical studies of ixekizumab, 73% of patients achieved overall sPGA 0/1, and 40% achieved overall sPGA 0 at week 12.[10] Clinical response was rapid, with significant improvement as early as week 1 for sPGA-G 0/1, sPGA-G 0 and overall sPGA 0/1, and as early as week 4 for overall sPGA 0.

Ixekizumab resulted in clinically meaningful improvements in genital itch and HRQoL, and significantly reduced the negative impact of GenPs on the frequency of sexual activity at week 12. Nearly 60% of patients receiving ixekizumab (with a baseline genital itch NRS ≥ 3) displayed a clinically meaningful improvement at week 12, with significant improvement as early as week 2. Among patients who reported an impact on sexual frequency at baseline due to GenPs (GenPs-SFQ item 2 score ≥ 2), nearly 80% receiving ixekizumab improved to the point that their frequency of sexual activity was never or rarely limited by GenPs at week 12, with significant improvement observed as early as week 1. HRQoL also significantly improved with ixekizumab, with 45% of patients receiving ixekizumab reporting no clinically significant impact on HRQoL at week 12.

The overall safety profile of ixekizumab in this study was comparable with those reported in previous studies of ixekizumab in moderate-to-severe plaque psoriasis.[10] Most TEAEs were mild or moderate in severity and discontinuations due to AEs were rare (one ixekizumab-treated patient). During the blinded treatment period, only one serious AE was reported, in a patient receiving placebo, and no deaths occurred.

The study population was globally diverse, with 149 patients enrolled from 34 sites in seven countries. This study is the only phase III, randomized, placebo-controlled, double-blinded clinical trial that has evaluated the efficacy of any therapy for the treatment of GenPs. Patients with both lower (1% to < 10%) and higher (≥ 10%) BSA involvement were included in this study. Thus, this study is among a small number of clinical trials investigating systemic therapy for plaque psoriasis in patients with < 10% BSA involvement where the severity and impact of the disease is considerable. A limitation of this study is that it did not include an active comparator, in part due to a lack of any well-established treatments for moderate-to-severe GenPs. Additionally, the study population was predominantly white and male. Lastly, this study had a relatively short duration. However, continued monitoring of the efficacy and safety of ixekizumab for GenPs is currently ongoing during an open-label extension period.

Although GenPs is a common and burdensome manifestation of plaque psoriasis,[1–3] there are few published open-label studies that have evaluated the efficacy of interventional treatments for GenPs.[7–9,16] In this study, ixekizumab provided rapid and significant improvement in GenPs that was consistent across lower and higher BSA subgroups. Ixekizumab also provided rapid and significant improvement in the impact of GenPs on the frequency of sexual activity and in HRQoL.