Long-Term Safety of Ivermectin 1% Cream vs Azelaic Acid 15% Gel in Treating Inflammatory Lesions of Rosacea: Results of Two 40-Week Controlled, Investigator-Blinded Trials

November 2014 | Volume 13 | Issue 11 | Original Article | 1380 | Copyright © November 2014

Linda Stein Gold MD,1 Leon Kircik MD,2 Joseph Fowler MD,3 J. Mark Jackson MD,4 Jerry Tan MD,5
Zoe Draelos MD,6 Alan Fleischer MD,7 Melanie Appell MD,8 Martin Steinhoff MD PHD,9
Charles Lynde MD,10 Jeffrey Sugarman MD PhD,11 Hong Liu MSc,12 and Jean Jacovella MD13 on behalf of the Ivermectin Phase 3 Study Group

1Henry Ford Medical Center, Department of Dermatology, Detroit, MI
2Icahn School of Medicine at Mount Sinai and DermResearch, PLLC, Louisville, KY
3Dermatology Specialists Research, Louisville, KY
4University of Louisville, Division of Dermatology, Louisville, KY
5Western University and Windsor Clinical Research, Inc., Windsor, ON, Canada
6Department of Dermatology, Duke University School of Medicine, Durham, NC
7Department of Dermatology, Wake Forest University Health Sciences, Winston, Salem, NC
8Total Skin and Beauty Dermatology Center, PC, Birmingham, AL
9Department of Dermatology and UCD Charles Institute for Translational Dermatology, University College Dublin, Dublin, Ireland
10Lynderm Research, Inc., Markham, ON, Canada
11Redwood Family Dermatology, Santa Rosa, CA
12Galderma R&D, Cranbury, NJ
13Galderma R&D, Sophia Antipolis, France

Papulopustular rosacea (PPR) is characterized by facial erythema and inflammatory lesions believed to be primarily caused by dysregulation of the innate immune system. More recent evidence also suggests that Demodex folliculorum mites may contribute to the etiology of PPR. Ivermectin (IVM) 1% cream is a novel topical treatment developed to treat PPR. Two phase 3 trials have demonstrated that IVM 1% cream was significantly better than vehicle at investigator global assessment (IGA) success rate and lesion reductions and that it was safe and well tolerated. Two 40-week extension studies of those trials were conducted to assess the long-term safety of IVM 1% cream vs azelaic acid (AzA) 15% gel. Subjects originally treated with IVM 1% continued on IVM 1% and those originally treated with vehicle switched to AzA 15% gel. IVM 1% cream was safe throughout the study with a lower incidence of related adverse events (AEs) compared to AzA 15% gel. No subjects in the IVM 1% cream group discontinued either study due to a related AE. IVM 1% also continued to be efficacious during the 40-week extension studies as the percentage of subjects with IGA scores of clear or almost clear was higher at the end of the study compared to baseline. The results of these 40-week extension studies support the use of IVM 1% cream as a long-term therapy for PPR as IVM 1% cream was shown to be safe and effective for up to 52 weeks of total treatment.

J Drugs Dermatol. 2014;13(11):1380-1386.


Papulopustular rosacea (PPR) is a chronic, facial skin disease characterized by facial erythema and inflammatory lesions (papules and pustules).1 Approximately 16 million people in the US are affected with rosacea, which has a negative effect on quality of life.2,3 The exact causes of rosacea remain unknown, but dysregulation of the innate immune system is believed to be central to the pathophysiology of this disease.4 Specifically, increased levels of cathelicidin and IL-1b activate inflammatory cascades that promote neutrophil recruitment, inflammation, and pain associated with rosacea.4-7 Additionally, dysregulation of the adaptive immune system (eg, T cells and dendritic cells) as well as the neurovascular system (eg, ion channels) have been reported.8-11 Interestingly, elevated numbers of B cells have been found in some PPR and phymatous rosacea (PhR) patients, but not in erythematotelangiectatic rosacea (ETR) patients, indicating involvement of adaptive immune reactions in PPR and PhR patients.8
Demodex folliculorum mites have emerged as a possible contributing factor in rosacea.12 These mites colonize up to 100% of the adult population and are normally commensal organisms.13-15 However, rosacea patients have a 5.7 fold increase in