Enstilar should be used once daily for 4 weeks at a total daily dose of no more than 15g. An area of skin the size of an adult's palm can be treated with 0.5g of foam (the amount delivered by depressing the applicator for approximately two seconds) and no more than 30% of the total body surface area should be treated at once.
Calcipotriol is a synthetic vitamin D3 analogue that works mainly to inhibit proliferation and induce differentiation of keratinocytes. Betamethasone is a synthetic corticosteroid. In psoriasis it works by suppressing the immune system, particularly the production of pro-inflammatory cytokines and chemokines, thereby inhibiting T cell activation.
Combination versus individual components
Calcipotriol and betamethasone have greater anti-inflammatory and antiproliferative effects in combination than alone, as shown by a randomised, phase II study that compared the combination foam with individual calcipotriol and betamethasone foams in 302 patients with at least mild psoriasis of the body and scalp.
After 1 week of treatment, more patients using the combination foam achieved treatment success in terms of body psoriasis (defined as 'clear' or 'almost clear' according to the Physician's Global Assessment; 6.0%) than using calcipotriol foam (2.0%) or betamethasone foam (4.0%).
After 4 weeks (primary endpoint), the advantage of the combination became significant, with 45% of patients achieving treatment success. Corresponding success rates in the groups treated with the individual calcipotriol and betamethasone foams were 14.9% (odds ratio 4.34 [95% CI 2.16–8.72], p<0.001) and 30.7% (odds ratio 1.81 [95% CI 1.00–3.26], p=0.047), respectively.
Combination versus vehicle control
PSO-FAST, a randomised, double-blind, phase III trial (n=426), compared the safety and efficacy of the combination foam with foam vehicle in patients with at least mild psoriasis of the trunk and/or limbs.
At week 4, significantly more patients using the combination foam achieved treatment success than using the vehicle foam, according to the Physician's Global Assessment (53.3% vs 4.8%, odds ratio 30.3 [95% CI 9.7–94.3], p<0.001). The combination foam group also experienced significantly greater itch relief than the vehicle group (p=0.010 at day 3; p<0.001 from day 5).
Calcipotriol/betamethasone foam was well tolerated, with adverse reactions occurring in 3.1% of treated patients compared with 1.9% of those using vehicle foam.
Foam versus ointment
In a randomised, 4-week phase II trial (n=376), calcipotriol/betamethasone foam showed significantly greater efficacy than and similar tolerability to calcipotriol/betamethasone ointment.
At week 4, significantly more patients using the foam achieved treatment success than using the ointment (54.6% vs 43.0%, odds ratio 1.7 [95% CI 1.1–2.8], p=0.025). The incidence of adverse effects was similarly low across the two groups and most events were described as mild.
Application site reactions are the most frequently reported adverse reactions.