Psoriasis Area and Severity Index scores assess both the severity and extent of psoriasis. A PASI score lower than 5 often is considered indicative of mild psoriasis, a score of 5 to 10 indicates moderate disease, and a score higher than 10 indicates severe disease.19 The maximum PASI score is 72. The PASI efficacy outcomes used in these analyses were based post hoc on the proportion of patients who achieved an absolute total PASI score of 3 or lower, 2 or lower, and 1 or lower.
Efficacy analyses were based on pooled data for all patients in the PSOARING trials who had a PGA score of 2 to 4 (mild to severe) before treatment with tapinarof cream 1% in the intention-to-treat population using observed cases. Time-to-target analyses were based on Kaplan-Meier (KM) estimates using observed cases.
Safety analyses included the incidence and frequency of adverse events and were based on all patients who received tapinarof cream 1% in the PSOARING trials.
RESULTS
Baseline Patient Demographics and Disease Characteristics
The pooled efficacy analyses included 915 eligible patients (Table). At baseline, the mean (SD) age was 50.2 (13.25) years, 58.7% were male, the mean (SD) weight was 92.2 (23.67) kg, and the mean (SD) body mass index was 31.6 (7.53) kg/m2. The percentage of patients with a PGA score of 2 (mild), 3 (moderate), or 4 (severe) was 13.9%, 78.1%, and 8.0%, respectively. The mean (SD) PASI score was 8.7 (4.23) and mean (SD) total BSA affected was 7.8% (4.98).
Efficacy
Achievement of BSA-Affected Targets—The NPF-recommended target of 1% or lower total BSA affected within 3 months was achieved by 40% of patients (KM estimate [95% CI, 37%-43%])(Figure 1). Across the total trial period of up to 52 weeks, a total BSA affected of 1% or lower was achieved by 61% of patients (561/915), with the median time to target of approximately 4 months (KM estimate: 120 days [95% CI, 113-141])(Supplementary Figure S2a). Approximately 50% of patients (455/915) achieved a total BSA affected of 0.5% or lower, with a median time to target of 199 days (KM estimate [95% CI, 172-228)(Figure 1; Supplementary Figure S2b).
FIGURE 1. Pooled analysis of total body surface area (BSA) affected targets achieved by patients with mild to severe plaque psoriasis treated with tapinarof cream 1% once daily (QD) across a trial period up to 52 weeks in PSOARING 1, PSOARING 2, and PSOARING 3 (target total BSA affected, ≤1% [National Psoriasis Foundation [NPF]−recommended target]; target total BSA affected, ≤.5%)(N=915). These analyses included patients receiving continuous or intermittent tapinarof monotherapy in the 12-week pivotal trials (PSOARING 1 and PSOARING 2) and in the forced-withdrawal design of PSOARING 3 (treatment was stopped when patients achieved a Physician Global Assessment score of 0).
FIGURE 2. Total Psoriasis Area and Severity Index (PASI) score targets achieved by patients with mild to severe plaque psoriasis treated with tapinarof cream 1% once daily across a trial period up to 52 weeks in PSOARING 1, PSOARING 2 (target PASI score), and PSOARING 3 (target PASI score ≤3, ≤2, and ≤1)(N=915). These analyses included patients receiving continuous or intermittent tapinarof monotherapy in the 12-week pivotal trials (PSOARING 1 and PSOARING 2) and in the forced-withdrawal design of PSOARING 3 (treatment was stopped when patients achieved a Physician Global Assessment score of 0).
Achievement of Absolute PASI Targets—Across the total trial period (up to 52 weeks), an absolute total PASI score of 3 or lower was achieved by 75% of patients (686/915), with a median time to achieve this of 2 months (KM estimate: 58 days [95% CI, 57-63]); approximately 67% of patients (612/915) achieved a total PASI score of 2 or lower, with a median time to achieve of 3 months (KM estimate: 87 days [95% CI, 85-110])(Figure 2; Supplementary Figures S3a and S3b). A PASI score of 1 or lower was achieved by approximately 50% of patients (460/915), with a median time to achieve of approximately 6 months (KM estimate: 185 days [95% CI, 169-218])(Figure 2, Supplementary Figure S3c).
Illustrative Case—Case photography showing the clinical response in a 63-year-old man with moderate plaque psoriasis in PSOARING 2 is shown in Figure 3. After 12 weeks of treatment with tapinarof cream 1% QD, the patient achieved all primary and secondary efficacy end points. In addition to achieving the regulatory end point of a PGA score of 0 (clear) or 1 (almost clear) and a decrease from baseline of at least 2 points, achievement of 0% total BSA affected and a total PASI score of 0 at week 12 exceeded the NPF and EADV consensus treatment targets.10,11 Targets were achieved as early as week 4, with a total BSA affected of 0.5% or lower and a total PASI score of 1 or lower, illustrated by marked skin clearing and only faint residual erythema that completely resolved at week 12, with the absence of postinflammatory hyperpigmentation.
