On August 13, Eli Lilly published results from IXORA-R, its Phase IV head-to-head psoriasis trial showing that Taltz (ixekizumab) is superior to Tremfya (guselkumab).

This is the first Phase IV head-to-head trial that uses the Psoriasis Area Severity Index (PASI) 100 score as the primary endpoint. In the trial, the efficacy and safety of IL-17A inhibitor Taltz, and Johnson and Johnson’s IL-23 inhibitor, Tremfya were compared. With this in mind, GlobalData believes that this could place Taltz as a more favorable option for psoriasis patients. 

Details of the trial

IXORA-R enrolled 1,027 patients with moderate-to-severe psoriasis. Patients were randomised to receive subcutaneous injections of either Taltz (160mg at Week 0, followed by 80mg at Weeks 2, 4, 6, 8, 10, and 12, then 80mg every 4 weeks) or Tremfya (100mg at Weeks 0 and 4 and then every 8 weeks thereafter). The trial lasted for a total of 24 weeks, with the primary analysis conducted at 12 weeks. 

Taltz met the primary endpoint of superiority compared to Tremfya at the 12 weeks post-treatment mark. Additionally, Taltz met all major secondary endpoints up to week 12. This includes superiority over Tremfya in the proportion of patients achieving PASI 75 at Week 2, PASI 90 at Weeks 4 and 8, PASI 100 at Weeks 4 and 8. It also includes static Physician’s Global Assessment (sPGA) 0 at Week 12, and PASI 50 at Week 1.

Eli Lilly has also planned to release further results from this trial in 2020 regarding the key secondary endpoint of proportion of patients achieving PASI 100 at 24 weeks. 

Looking forward

GlobalData believes that head-to-head trials of this nature will drive increased competition in the psoriasis market. This would allow for better-informed prescribing decisions for physicians managing psoriasis. Furthermore, the psoriasis market is already highly competitive; pharmaceutical companies battle for dominance in this highly lucrative space. 

Taltz was the second IL-17 inhibitor to launch in the psoriasis market after Novartis’ Cosentyx. The latter has recently shown that it has dual inhibition of IL-17A and IL-23. GlobalData believes that IL-23 inhibitors could be overshadowed by anti-IL-17 biologics, which have demonstrated strong efficacy.

According to GlobalData’s report Plaque Psoriasis: Global Drug Forecast and Market Analysis to 2027, Taltz is anticipated to generate sales of $904.6M within the seven major markets (US, France, Germany, Italy, Spain, UK, and Japan) by 2028. With impressive clinical trial data and the efforts of Eli Lilly’s marketing team, Taltz could be regarded as a more efficacious treatment option for psoriasis compared to treatments of the IL-23 and IL-17 classes.