Calcipotriol Other names: Calcipotriene

Calcipotriol is a derivative of vitamin D for topical use on psoriasis. It probably works by suppressing keratinization. Advantage of substance or absence of odor and non-coloring of clothing.

Psoriasis is the disease where skin cells are produced at a rate much higher than normal. This results in the creation of flakes on the skin and the area gets red. The ointment-cream restores the skin cell’s production rate to its normal value.

Calcipotriol is a vitamin D derivative. In vitro data show that calcipotriol induces differentiation and suppresses proliferation of keratinocytes. The effect of calcipotriol in psoriasis is ascribed mainly to this.

An effect, first of all on the desquamation, then on the infiltration and finally on the erythema, is seen after two to four weeks of treatment. The maximum effect is usually achieved after six weeks.

No data are available on the absorption of calcipotriol solution.

Data from a single study containing 5 evaluable patients with psoriasis treated with 0.3–1.7 g of a 50 micrograms/g tritium labelled calcipotriol ointment suggested that less than 1% of the dose was absorbed. However, total recovery of the tritium label over a 96 hour period ranged from 6.7 to 32.6%, figures maximised by uncorrected chemiluminescence. There were no data on 3H tissue distribution or excretion from the lungs.

The effect on calcium metabolism is approximately 100 times less than that of the hormonally active form of vitamin D3.

A dermal carcinogenicity study in mice revealed no special hazards for humans.

Calcipotriol has shown maternal and foetal toxicity in rats and rabbits when given by the oral route at doses of 54 μg/kg/day and 12 μg/kg/day, respectively. The foetal abnormalities observed with concomitant maternal toxicity included signs indicative of skeletal immaturity (incomplete ossification of the pubic bones and forelimb phalanges, and enlarged fontanelles) and an increased incidence of supernumerary ribs.

The significance for humans is unknown.

In another study where albino hairless mice were repeatedly exposed to both ultraviolet (UV) radiation and topically applied calcipotriol for 40 weeks at doses which correspond to 9, 30 and 90 µg/m²/day (equivalent to 0.25, 0.84 and 2.5 times the maximum recommended daily dose for a 60 kg adult, respectively), a reduction in the time required for UV radiation to induce the formation of skin tumours was observed (statistically significant in males only), suggesting that calcipotriol may enhance the effect of UV radiation to induce skin tumours. The clinical relevance of these findings is unknown.