Umezawa 2016.

Methods	Randomised, placebo‐controlled trial 26 centres, Tokyo (both hospital and community centre clinics) Period of Inclusion: September 2005 to August 2006
Participants	Inclusion criteria Moderate or severe PPP: ≥ 7 in total score of skin findings and ≥ 3 in the score of pustules/vesicles. Participants were enrolled in the study if the condition of their disease changed little after treatment with placebo during a 1‐week run‐in period Exclusion criteria Received treatment with immunosuppressive drugs (e.g. ciclosporin, methotrexate), immunomodulatory drugs (e.g. etretinate, steroids), drugs affecting calcium metabolism (e.g. vitamin D3 analogues, calcitonin, sex hormones), or phototherapy for lesions of PPP within the 8 weeks before the day of study initiation Applied very strong topical corticosteroids or topical vitamin D3 analogues to lesions of PPP within the 4 weeks before the day of study initiation Applied strong topical corticosteroids to lesions of PPP within the 2 weeks before the day of study initiation History of allergy to topical vitamin D3 analogue or other medications Serum Ca level was > 10.5 mg/dL on the day of providing informed consent Baseline data: randomised on a 1:1 basis to OCT (a white translucent ointment containing 25 lg/g of maxacalcitol) (n = 95) group or placebo group (n = 93) Mean age, years: 49.7 ± 11.3; 54.6 ± 10.7 Male/female: 24/70; 27/66 Proportion of participants with psoriatic lesions elsewhere: not specified Withdrawal: 1 participant in the OCT group was not included in the FAS due to lack of evaluable data after investigational treatment
Interventions	Intervention 1 A: OCT (25 microg/g of maxacalcitol ointment) (94 participants) Intervention 2 B: placebo (93 participants) Co‐interventions: none Duration of treatment: 8 weeks
Outcomes	Primary outcome Total score of skin findings at the last observation at week 8 or date of discontinuation (severity of main symptoms associated with PPP, erythema, pustules/vesicles, and keratinisation/scales, using a 5‐point scale (4 = severe, 3 = moderate, 2 = mild,1 = slight, and 0 = none) Secondary outcomes Improvement rating of skin findings and the scores of each skin finding at week 8
Notes	This study was financially supported by Maruho. The topical study drug was provided by Chugai Pharmaceutical. YU has served as a paid speaker for Maruho. HN has served as a paid speaker, advisory board member, and consultant for Maruho
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Comment: no information
Allocation concealment (selection bias)	Unclear risk	Comment: no information
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Quote: "white translucent ointment" Comment: double‐blind, placebo‐controlled trial and both OCT and placebo were presented as white translucent ointment. However, no information on allocation concealment or packaging
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Comment: double‐blind, placebo‐controlled trial and both OCT and placebo were presented as white translucent ointment. No information on measure applied to guarantee blind assessment
Incomplete outcome data (attrition bias) All outcomes	Low risk	Quote: "One subject in the OCT group was not included in the FAS due to a lack of evaluable data after the investigational treatment" Comment: only 1 participant left and was not included in the analysis
Selective reporting (reporting bias)	Unclear risk	Comment: no protocol found to guarantee that all planned outcomes are presented in the results