Modified glutathione cream effective in mild-to-moderate rosacea

The modified glutathione (GSH-C4) with beta glycyrrhetic and azelaic acids cream is effective in the treatment of mild-to-moderate rosacea, with local tolerability consistent with other antirosacea medications, according to a study presented at the 29th Congress of the European Academy of Dermatology and Venereology (EADV 2020).

Thirty adult patients with mild-to-moderate inflammatory rosacea participated in this two-centre (University Hospital Catania and Modena, Italy), prospective, assessor-blinded trial and were instructed to apply the cream twice daily for 8 weeks.

The researchers conducted clinical evaluation at baseline and at 4 and 8 weeks by Investigator Global Assessment (IGA) score based on a 7-point scale (from 0=clear to 6=severe erythema and several papules/pustules) and total lesion counts in both sides.

VISIA-CR imaging was used to perform an instrumental evaluation of erythema degree at the Catania site, and Antera 3D analysis was carried out at the Modena site. A self-administered questionnaire was used to assess tolerability at 4 and 8 weeks. Finally, statistical analysis was done using the GraphPad statistical software.

Thirty individuals (mean age, 38 years; 22 women) were included after providing a written informed consent, of whom 26 (87 percent) completed the study phases. Four participants discontinued the trial prematurely due to low skin tolerability (n=3) or lost to follow-up (n=1).

Mean IGA score at baseline was 2.6 (standard deviation [SD], 0.9), which dropped to 2.3 (SD, 1.2) at week 4 (p=NS). This further decreased to 1.2 (SD, 1) at week 8 compared with baseline (mean difference, 1.3, 95 percent confidence interval, 0.9–1.7; p=0.0001). [EADV 2020, abstract P0034]

The mean inflammatory lesion count evaluated on VISIA photographs were 5.1 (SD, 2.5) at baseline, 2.8 (SD, 1.9) at week 4, and 1.9 (SD, 1.7; –63 percent vs baseline) at week 8 (p=0.0001; ANOVA Test), representing a 63-percent reduction. Inflammatory lesion count performed on VISIA images confirmed this reduction (from 4.5 at baseline to 1.7 lesions at week 8).

“[A] similar evolution was observed for the clinical and instrumental [erythema severity score] with a reduction of 56 percent (clinical) and 48 percent (VISIA), respectively, at week 8 in comparison with the baseline,” the researchers said.

The positive evolution observed clinically was confirmed by Antera 3D photographs, with a significant reduction (–24 percent) in haemoglobin content from 1.88 at baseline to 1.44 at week 8.

Five cases of local side effects were reported. Of note, product tolerability was rated excellent in 25 (83 percent) of rosacea patients.

In an earlier study, azelaic acid in 20% cream and 15% gel formulations has been shown to be effective in the treatment of papulopustular rosacea, specifically in reducing mean inflammatory lesion count and erythema severity. It also appears to be equally effective, if not better, compared with metronidazole. [Arch Dermatol 2006;142:1047-1052]

“Rosacea is a very common, chronic inflammatory disease characterized by flushing, erythema, and inflammatory lesions. Increased oxidative stress plays a relevant pathogenetic role in rosacea,” the researchers said.

“C4-GSH is a modified GSH molecule characterized by a better intracellular bioavailability and longer half-life. A cream containing C4-GSH (0.1%) with beta-glycyrrethic (0.5%) and azelaic acids (10%) is available,” they added.