Oral Doxycycline for Long-Term Rosacea Management

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Relapse and efficacy during long-term SDD40 therapy vs placebo in patients with rosacea is evaluated.

Oral doxycycline at subantibiotic doses may be effective for the long-term management of rosacea, study data published in Dermatologic Therapy suggests.

This 2-part study assessed the clinical effects of subantibiotic dose oral doxycycline 40 mg modified release (SDD40) in patients with moderate to severe rosacea. Part 1 was an open-label, 12-week study in which patients with rosacea received both SDD40 and topical metronidazole gel 1%. Patients who responded to treatment in part 1 were enrolled in part 2: a 40-week study in which patients were randomly assigned to receive once-daily SDD40 or placebo. Treatment response was defined as a 2-grade improvement or a score of “clear/near clear” on the Investigator’s Global Assessment (IGA). Relapse was defined by a return to baseline IGA score, a return to baseline lesion count, or any clinical condition that necessitated a change in treatment. Adverse events were monitored throughout the trial.

Part 1 enrolled 235 patients, of whom 130 met the definition of treatment success and were randomly assigned to receive either placebo (n=65) or SDD40 (n=65) in part 2. Demographic characteristics were comparable between study arms. Mean age was 47.2 ± 13.2 years in the SDD40 group and 51.7 ± 12.8 years in the placebo group. The majority of part 2 enrollees were women (66.2%), White (96.9%), and non-Hispanic/Latino (80%).

After 40 weeks of treatment, the rate of relapse was significantly lower in the SDD40 group compared with the placebo group (13.8% vs 27.7%; P <.05). Relapse also occurred earlier in the placebo group: 15.4% patients in the placebo arm experienced relapse by week 4, compared to 6.2% in the SDD40 group. In the SDD40 group, no relapses were observed after week 12 of treatment; relapses occurred at weeks 24 and 28 in the placebo group. Treatment was generally well-tolerated by patients; adverse events were of mild to moderate severity and occurred at comparable rates between study arms. Patients who received SDD40 reported greater improvements in stinging/burning sensations during the 40-week trial.

“These data support that subantibiotic dose doxycycline is a rational, safe, and effective long-term therapy for inflammatory lesions of rosacea,” investigators wrote. However, they note, further study is necessary to better establish the efficacy of this treatment and explore additional options.

Disclosure: A study author declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures. 


Del Rosso JQ, Brantman S, Baldwin H. Long-term inflammatory rosacea management with subantibiotic dose oral doxycycline 40 mg modified-release capsules once daily. Dermatol Ther. 2022;35(1):e15180. doi:10.1111/dth.15180