OBJECTIVES : The physician-rendered Psoriasis Area Severity Index (PASI) is the current benchmark of primary endpoints for moderate to severe psoriasis clinical trials. This study explores the importance of patient reported outcomes (PROs) compared to PASI as objective measure of disease severity, risk of infections or frequency of drug administration on dermatologist's decision to prescribe a biologic subcutaneous treatment in moderate to severe psoriasis.

METHODS : Two online surveys of 130 and 129 US dermatologists each using direct and indirect elicitation via discrete choice experiment (DCE) were conducted in 2016 and 2017. In both surveys, respondents tested combinations of 6 endpoints in 8 dual-choice tasks to understand what they use to asses biologic treatments and to quantify what trade-offs rules they apply. The following endpoints were tested: PASI 75 or PASI 90 (defined as 75% or 90% of change in PASI score from baseline, respectively), risk of infections, frequency of drug administration and three PRO attributes (relief of depression or anxiety, complete relief of itching and impact on usual activities).

RESULTS : Results showed that 76% of dermatologists use both PASI and PROs when selecting a biologic treatment for patients with moderate to severe psoriasis, while 12% and 12% use PASI only and PRO only, respectively. PASI 90 was the most important attribute (35% of overall decision weight) but the PRO attributes, when combined, were as important (36% of overall weight). Risk of infections and frequency of administration were less important (20% and 9% of overall decision weight, respectively). Similar outcomes were observed in the survey using PASI 75.

CONCLUSIONS

Although PASI remains important for dermatologists when selecting a biologic treatment in moderate to severe psoriasis, PROs are also highly valued and used in the treatment decision process. This highlights the importance of collecting PRO data in psoriasis clinical trial programs.