Patient-Reported Outcomes by Baseline Body Surface Area Involvement Among Individuals Initiating Biologic Therapy: Results from the CorEvitas Psoriasis Registry.

Introduction: Psoriasis body surface area (BSA) of 10% or more has been a major criterion for determining systemic therapy eligibility. However, patients with BSA < 10% and even ≤ 3% may have high disease burden and difficulties accessing biologics. To assess psoriasis burden among patients with BSA ≤ 10%, this study characterized patient-reported outcomes (PROs) across BSA categories among systemic treatment-naïve patients initiating biologic therapy.

Methods: Patients from the CorEvitas Psoriasis Registry initiating biologics between April 2015 and September 2023 were categorized according to low (< 3%), medium (3-10%), or high (> 10%) BSA involvement. Measures assessed at initiation of biologic therapy included health-related quality of life, itch, pain, fatigue, psoriatic arthritis, psoriasis disease characteristics, and medical history. Overlap between BSA groups for each outcome was calculated via non-parametric Mann-Whitney statistic transformation (range 0.0-1.0; 0.5 indicates complete similarity [i.e., for a comparison between low and high BSA groups, overlap of 0.5 means there is 50% probability that a randomly selected patient with low BSA would have the same or greater PRO burden as one with high BSA]; 0 or 1 indicates complete dissimilarity) to determine whether each measure differed in randomly selected patients with low or medium versus high BSA.

Results: Of 1640 patients who initiated biologics, 7.0% had low BSA, 46.9% had medium BSA, and 46.2% had high BSA involvement. PRO overlap statistics ranged from 0.52 to 0.59 and from 0.60 to 0.70 for randomly selected patients with high versus medium and low BSA, respectively, indicating patients with high and medium BSA are likely to have similar levels of disease burden, and patients with high BSA are slightly more likely to have higher disease burden than those with low BSA. Near complete overlap (range 0.44-0.58) was observed for psoriasis disease characteristics and medical history in the low versus high and medium BSA groups.

Conclusion: Observed overlap in PROs across BSA categories shows that patients with low BSA can experience similarly poor quality of life and high symptom burden to those with higher BSA. These findings support the appropriateness of considering biologic therapies for patients with low BSA and indicators of high disease burden.

Trial Registration: ClinicalTrials.gov: NCT02707341.