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Center for Global Research Data

Geospatial and Seasonal Variation in Psoriasis Severity Analysis of Placebo Response Data from Phase 3 placebo-controlled trials in moderate-severe psoriasis.

Lead Investigator: Martin Okun, Fort HealthCare

Title of Research Proposal: Geospatial and Seasonal Variation in Psoriasis Severity Analysis of Placebo Response Data from Phase 3 placebo-controlled trials in moderate-severe psoriasis.

Vivli Data Request: 4316

Funding Source: None

Potential Conflicts of Interest: A potential conflict of interest is that I am a former employee of Abbott Laboratories and AbbVie and serve as a consultant and on the speaker’s bureau for AbbVie. However, as I am accessing only placebo data, the relevance of my past and current work experience with AbbVie is uncertain.

Summary of the Proposed Research:

In placebo controlled randomized clinical trials of new therapeutics for moderate to severe psoriasis patients, some patients assigned to the placebo arm experience clinical improvement in their psoriasis signs. The basis for this observed improvement is not clear. Possible explanations include: random fluctuations in disease severity, increased attention to skin care instigated by study personnel translating into more diligent application of emollients by the subject, or the subject experiencing the psychological benefit of inaccurately believing that he or she is receiving effective experimental therapy (i.e., the true “placebo” effect). In addition to these explanations, it is also possible that seasonal fluctuations in ambient UV exposure may account for some of the response observed among placebo patients. The purpose of the proposed research is to investigate if and to what extent fluctuations in ambient UV exposure could be causing improvements in psoriasis among patients being treated with placebo.

There is evidence from the dermatologic literature for seasonal variation in psoriasis severity: Pascoe and Kimball (2015) collected psoriasis PGA (Physician’s Global Assessment) scores from psoriasis patients in a large New England-based healthcare system, analyzed the data for seasonal variations, and noted that a higher percentage of psoriasis patients were clear or almost clear in the summer than in the winter, with statistically significant variation in the percentage of patients who were clear or almost clear across the different seasons. This outcome is biologically plausible, because UV (ultraviolet) light exposure is greater in the summer than in the winter, with the difference in exposure more marked at higher latitudes, and because UV exposure is known to ameliorate psoriasis. However, the results from Pascoe and Kimball may be confounded by the concomitant treatments that the psoriasis patients were receiving at their office visits. To eliminate the effect of this confounding, analysis of controlled clinical trial data would be valuable.

Requested Studies:

A Phase III, Multicenter Study of the Efficacy and Safety of Adalimumab Treatment in Subjects With Moderate to Severe Chronic Plaque Psoriasis
Sponsor: AbbVie
Study ID: NCT00237887
Sponsor ID: M03-656

BI 655066/ABBV-066 (Risankizumab) Versus Ustekinumab and Placebo Comparators in a Randomized Double Blind trIal for Maintenance Use in Moderate to Severe Plaque Type Psoriasis (UltIMMa-1)
Sponsor: AbbVie
Study ID: NCT02684370
Sponsor ID: M16-008

BI 655066 Versus Ustekinumab and Placebo Comparators in a Randomized Double Blind trIal for Maintenance Use in Moderate to Severe Plaque Type Psoriasis-2 (UltIMMa-2)
Sponsor: AbbVie
Study ID: NCT02684357
Sponsor ID: M15-995