Ixekizumab effective in psoriasis across racial groups, but patients report differences

Key takeaways:

• All groups achieved similar rates of PASI improvement.
• Patient-reported outcomes were worse among Black/African American and American Indian/Alaska Native patients.

Efficacy outcomes of ixekizumab through 12 weeks of treatment for psoriasis were consistent across multiple racial groups, although patient-reported outcomes were not, according to a study.

“There are only a limited number of studies that investigate racial differences in treatment response to different therapies,” Amy McMichael, MD, of the department of dermatology at Wake Forest University School of Medicine, and colleagues wrote. “Therefore, there is a need to consider data from diverse phenotypes when deciding a treatment strategy in patients with psoriasis.”

McMichael and colleagues evaluated the treatment response to ixekizumab, an interleukin-17A antagonist, in 1,825 patients with psoriasis across racial groups. The authors used pooled data from five clinical studies including three UNCOVER trials and two IXORA trials.

All patients received an on-label starting dose of ixekizumab 160 mg, followed by 80 mg every 2 weeks through 12 weeks of treatment. Most patients self-identified as white (90.7%) followed by Asian (4.2%), Black or African American (3.2%), American Indian or Alaska Native (0.7%) and Native Hawaiian or other Pacific Islander (0.3%). Additionally, 0.6% of patients reported more than one race, and four did not report race.

During treatment, all groups showed rapid PASI improvement from baseline that was sustained through 12 weeks. There were similar PASI 90 response rates among all groups — ranging from 71.7% in the Black or African American group to 80% in the Native Hawaiian or other Pacific Islander group — except for the American Indian or Alaska Native patients (41.7%).

On the other hand, some patient-reported outcomes differed across racial groups. The researchers called rates of DLQI scores of 0 or 1 similar between white (67.8%), Native Hawaiian or other Pacific Islander (60%) and patients reporting more than one race (90.9%); however, these rates were lower among Black or African American (35.3%) and American Indian or Alaska Native patients (33.3%).

According to the authors, the differences in DLQI scores may be attributed to “various factors including disease severity, dyspigmentation and cultural differences.” The sample sizes were also small in some groups, which the authors called a study limitation.

“These results should be considered with caution, however, as studies on treatment strategies for patients with skin of color are lacking, possibly due to the disproportionate representation of certain racial groups in the clinical trials and to a limited number of studies reporting outcomes based on race and/or ethnicity,” the authors concluded.