Calcipotriol cream combined with twice weekly broad-band UVB phototherapy: a safe, effective and UVB-sparing antipsoriatric combination treatment. The Canadian Calcipotriol and UVB Study Group.

BACKGROUND

Calcipotriol has been combined with a number of systemic antipsoriatric treatments, improving efficacy or reducing the systemic treatment required. Although studies on calcipotriol and UVB have also been performed, there are no data on the UVB-saving effect of calcipotriol combined with broad-band UVB to reduce overall UVB exposure, while maintaining efficacy.

OBJECTIVES

To assess the efficacy and safety of calcipotriol cream (50 microg/g) combined with twice weekly broad-band UVB and to determine if this treatment would require fewer UVB treatments and lower cumulative UVB irradiance when compared to a standard 3 times weekly broad-band UVB regime in patients with extensive psoriasis.

METHODS

This multicentre, prospective, randomised, parallel-group, vehicle-controlled, single-blind (investigator) study consisted of a 1-week wash-out phase, 12-week treatment phase and 12-week follow-up phase. Broad-band UVB equipment was standardised and calibrated prior to the study. The UVB starting dose was based on the patient's minimal erythema dose. Assessments included PASI, extent, severity and investigator and patient's overall assessments of the psoriasis.

RESULTS

Fewer exposures (12 vs. 19) and less cumulative UVB irradiance (1,570 vs. 5,430 mJ/cm(2)) were required by the calcipotriol + twice weekly UVB group to achieve 80% reduction in PASI (p < 0.001). Similarly, fewer exposures (22 vs. 25) and less cumulative UVB irradiance (4,147 vs. 9,670 mJ/cm(2)) were required by this group to achieve total clearance (p < 0.001). There was no difference in the PASI, patient's and investigator's overall assessments and number of adverse events recorded by either group for both the treatment and follow-up phases.

CONCLUSION

Calcipotriol cream + twice weekly broad-band UVB phototherapy is an effective and safe antipsoriatric treatment, resulting in fewer UVB exposures, lower cumulative irradiance and a saving of time.