Overall, 39% of participants who had moderate disease (IGA score, 3) at baseline were treatment successes with HP lotion at week 8 compared with 11.53% of participants treated with vehicle; 27.97% of participants with severe disease (IGA score, 4) were treatment successes, with at least a 3-grade improvement in IGA. No participants with severe psoriasis who were treated with vehicle achieved treatment success at week 8. Efficacy was similar in female and male participants, allowing for vehicle effects.
Severity of Signs of Psoriasis (Erythema, Plaque Elevation, and Scaling) at Target Lesion Site
Halobetasol propionate lotion was statistically superior to vehicle in reducing the psoriasis signs of erythema, plaque elevation, and scaling at the target lesion from week 2. At week 8, treatment success (at least a 2-grade improvement from baseline) was achieved by 51.48% (erythema), 57.64% (plaque elevation), and 58.98% (scaling) of participants compared with 17.85%, 23.61%, and 22.82%, respectively, with vehicle (all P<.001)(Figure 2).
Figure 2. Improvement in psoriasis signs of erythema, plaque elevation, and scaling at each study visit: participants categorized as treatment successes (intention-to-treat population pooled study data). Treatment success was defined as at least a 2-grade improvement from baseline. P<.001 at all time points for erythema and scaling. P<.001 at weeks 4, 6, and 8, and P=.056 at week 2 for plaque elevation.
BSA Assessment
Halobetasol propionate lotion was statistically superior to vehicle in reducing BSA from week 2. At week 8 there was a 35.20% reduction in mean BSA for HP lotion compared to 5.85% for vehicle (P<.001)(eFigure 2).
eFigure 2. Percentage reduction in mean body surface area (BSA) from baseline to week 8 (intention-totreat population pooled study data). Asterisk indicates P<.001 vs vehicle.
IGA×BSA Composite Score
At baseline, the mean IGA×BSA scores for HP lotion and vehicle were similar: 19.3 and 18.8, respectively. By week 8, the percentage change in mean IGA×BSA score with HP lotion was 49.44% compared to 13.35% with vehicle (P<.001). Differences were significant from week 2 (P<.001)(Figure 3).
Figure 3. Percentage reduction in IGA×BSA composite tool from baseline to week 8 (intention-to-treat population pooled study data). Asterisk indicates P<.001 vs vehicle. IGA indicates investigator global assessment; BSA, body surface area.
By week 8, 56.8% of participants (n=162) treated with HP lotion had achieved a 50% or greater reduction in baseline IGA×BSA compared to 17.2% of participants treated with vehicle (P<.001). Reductions of IGA×BSA-75 and IGA×BSA-90 were achieved in 39.3% and 19.3% of participants treated with HP lotion, respectively, compared with 9.7% and 2.8% of participants treated with vehicle (both P<.001)(eFigure 3).
eFigure 3. Achievement of 50% (IGA×BSA-50), 75% (IGA×BSA-75), and 90% (IGA×BSA-90) reduction in mean IGA×BSA by week 8 (intent-totreat population pooled study data). Asterisk indicates P<.001 vs vehicle. IGA indicates investigator global assessment; BSA, body surface area.
Safety Evaluation
Adverse event reports were low and similar between the active and vehicle groups. Overall, 61 participants (21.5%) treated with HP lotion reported AEs compared with 34 participants (23.9%) treated with vehicle (Table). The majority of participants treated with HP lotion (90.2%) had AEs that were mild or moderate. There was 1 AE of telangiectasia, not considered treatment related. There were 5 treatment-related AEs for HP lotion, all at the application site: dermatitis (0.7%; n=2), infection (0.4%; n=1), pruritus (0.4%; n=1), and discoloration (0.4%; n=1). There were no AE reports of skin atrophy or folliculitis.
Local Skin Reactions
Most LSRs at baseline were mild to moderate in severity. Itching was the most common, present in 76.8% of participants. Participant-reported burning/stinging was less common, reported by 40.6% of participants. Investigator-reported dryness was noted in 65.7% of participants. There was a rapid improvement in participant-reported itching as early as week 2 that was sustained to the end of the studies, with more gradual improvements in skin dryness and burning/stinging.
COMMENT
Plaque psoriasis is a chronic condition. The rationale behind the development of HP lotion 0.01% was to provide optimal topical treatment of moderate to severe psoriasis, allowing for the potential of prolonged use beyond the 2-week consecutive use normally applied to HP cream 0.05% in a light, once-daily, aesthetically pleasing lotion formulation that patients would prefer.