Oral R115866 in the treatment of moderate to severe plaque-type psoriasis.

BACKGROUND: R115866 (Rambazole) is a new generation all-trans retinoic acid metabolism blocking agent, highly specific against the retinoic acid 4-hydroxylase. The drug alleviates hyperproliferation and normalizes differentiation of the epidermis in animal models of psoriasis. OBJECTIVE: To explore the efficacy, safety and tolerability of systemic R115866 in patients with moderate to severe plaque-type psoriasis. PATIENTS AND METHODS: In this open label, single-arm trial, patients were treated with R115866, 1 mg/day for 8 weeks, followed by a 2-week treatment-free follow-up period. Patients were monitored for efficacy and safety. RESULTS: Nineteen patients (intent-to-treat population) were treated and 14 completed the entire study. Two patients discontinued due to lack of efficacy and three due to adverse events. At the end of the treatment, 26% of the patients showed at least 50% reduction in Psoriasis Area Severity Index (PASI) compared to baseline. Further improvement was observed at the end of the 2-week follow-up period where 47% of the patients showed a 50% or greater reduction in PASI. Kinetic data showed no evidence of accumulation of either R115866 or retinoic acid in plasma. The most common adverse events were pruritus, xerosis, cheilitis and an increase in blood triglycerides. The majority of adverse events were mild to moderate. No deaths or serious adverse events were reported. CONCLUSION: Eight-week daily treatment with 1 mg R115866 resulted in a significant reduction in PASI from baseline to end of therapy. Additional improvement was seen after the 2-week follow-up period. The drug was well tolerated. R115866 merits further evaluation to optimize its clinical efficacy and safety profile in moderate to severe plaque-type psoriasis.

Oral R115866 in the treatment of moderate to severe facial acne vulgaris: an exploratory study.

BACKGROUND: R115866 (Rambazole; Barrier Therapeutics NV, Geel, Belgium), a new-generation retinoic acid metabolism-blocking agent, is a nonretinoid compound enhancing intracellularly the endogenous levels of all-trans-retinoic acid by blocking its catabolism. By virtue of this property, and the proven positive effects of retinoids in the treatment of acne, R115866 could potentially be a useful drug for acne. OBJECTIVES: To explore the efficacy, safety and tolerability of systemic R115866 in male patients with moderate to severe facial acne vulgaris (at least 15 papules and/or pustules and at least two nodulocystic lesions). METHODS: In this exploratory trial, 17 patients were treated with oral R115866 1 mg once daily for 12 weeks, followed by a 4-week treatment-free period. RESULTS: At the end of treatment (week 12, n = 16) a mean reduction in inflammatory lesion count of 77.4% (P < 0.001), in noninflammatory lesion count of 58.3% (P < 0.001) and in total lesion count of 76.0% (P < 0.001) was observed as compared with baseline. All lesion counts were significantly reduced from week 4 onwards. Mild side-effects were reported occasionally. CONCLUSIONS: The current data indicate that treatment with oral R115866 1 mg once daily for 12 weeks in patients with moderate to severe facial acne vulgaris is efficacious and well tolerated and merits further investigation.

Oral liarozole vs. acitretin in the treatment of ichthyosis: a phase II/III multicentre, double-blind, randomized, active-controlled study.

BACKGROUND: Liarozole, a retinoic acid metabolism blocking agent, has been granted orphan drug status for congenital ichthyosis by the European Commission and the U.S. Food and Drug Administration. OBJECTIVES: The purpose of this trial was to investigate the efficacy, tolerability and safety of oral liarozole vs. acitretin in patients with ichthyosis. METHODS: In this double-blind comparative trial of liarozole vs. acitretin, 32 patients with ichthyosis were randomized to be treated with either oral liarozole 75 mg in the morning and 75 mg in the evening or with acitretin 10 mg in the morning and 25 mg in the evening for 12 weeks. Clinical efficacy, tolerability and safety were monitored. RESULTS: Between-group comparisons for efficacy and tolerability revealed no statistically significant differences except for scaling on the trunk at baseline which was significantly worse in the liarozole group (P = 0.024) and showed a more pronounced improvement in this group than in the acitretin-treated patients (P = 0.047). Based on the overall evaluation of the response to treatment at endpoint, 10 of 15 patients in the liarozole group and 13 of 16 patients in the acitretin group were considered by the investigator to be at least markedly improved. The expected retinoic acid-related adverse events were mostly mild to moderate and tended to occur less frequently in the liarozole group. No serious adverse events related to the drugs occurred. CONCLUSIONS: The present study indicates that liarozole at a daily dose of 150 mg is equally effective as a treatment for ichthyosis as acitretin but shows a trend towards a more favourable tolerability profile. The results of this trial warrant further clinical trials to confirm efficacy and safety of liarozole as an orphan drug in ichthyosis.