A double-blind crossover study of azaribine (6-azauridine triacetate) effects in 27 patients with psoriasis was conducted at a dosage of 125 mg/kg/day. Half of the subjects were given azaribine for the first six weeks before crossing over to the placebo. The others received the placebo for the first six weeks before crossing over. Clinical response was considered good to excellent in 18 out of 21 patients receiving medication, whereas 19 of the 20 patients on the placebo showed no improvement or deterioration of their skin lesions. Toxic side effects included a mild anemia and mental depression in some patients. Elevated urine orotic acidorotidine levels were noted for the first time in psoriatic patients receiving azaribine. Urine orotic acid-orotidine levels may be correlated with toxicity and clinical response.
Milstein HG, Cornell RC, Stoughton RB. Azaribine in the Treatment of PsoriasisA Low Dose, Double-Blind Evaluation. Arch Dermatol. 1973;108(1):43-47. doi:10.1001/archderm.1973.01620220015003