Role of C.acnes biofilms in antibiotic resistance is modest
Today's report also covers CO2 lasers, acne in transgender patients, real-world experience with clascoterone, and more (1,600 words, 7 minutes, 10 seconds)
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Good morning, and welcome to the 14th issue of Focus on Acne, presented by Skin Spectrum Weekly. This series provides up-to-date information on developing therapies and trends in acne treatment. We appreciate your feedback and suggestions and invite you to be in touch. Please write to us at health@chronicle.org
Role of C.acnes biofilms in antibiotic resistance is modest
While C. acnes can create biofilms, recent findings suggest its modest effectiveness in antibiotic resistance.
These findings come from a paper published in the Indian Journal of Dermatology, Venereology and Leprology (Jan. 17, 2025:1-6).
This descriptive cross-sectional study investigated the ability of C. acnes to form biofilms and its potential association with resistance to commonly used antibiotics.
For this study, researchers selected 88 patients with acne vulgaris and conducted clinical examinations and severity grading. They used Matrix-Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF-MS) to analyze bacterial samples, which were further subjected to biofilm testing using the microtiter plate assay.
Investigators isolated C. acnes from 43.1% of the samples (n=38). They observed the highest resistance with azithromycin (73.7%) followed by clindamycin (65.8%), doxycycline (15.8%), ampicillin (31.6%) and minocycline (5.3%). Some 37% of the isolates were resistant to at least two antibiotics, 63.2% of C. acnes had a weak capacity to form biofilms, and more than 60% showed resistance to at least two types of antibiotics and weak biofilm-forming capacity.
The authors note that limitations to the study include its single-centre nature, small sample size, and a lack of long-term follow-up of the patients. In addition, this study is representative of only C. acnes species.
“It is important to consider alternative mechanisms such as genetic or biochemical plasticity that may contribute to antibiotic resistance,” they write.
CO₂ laser supports topical timolol maleate Tx
Combined fractional CO₂ laser and topical timolol maleate 0.5% solution is significantly more effective than topical timolol maleate 0.5% solution alone in reducing erythema of inflammatory facial acne in adolescent men with Fitzpatrick's skin type III-IV.
These findings were published in Lasers in Medical Science (Feb. 1, 2025; 40(1):58).
Researchers included 30 adult patients with inflammatory facial acne in this study. Each patient received biweekly sessions of fractional CO2 laser on one side of the face followed by topical timolol maleate ophthalmic solution 0.5% once daily for seven days on both sides. Investigators evaluated outcomes two weeks after the first session, two weeks after the last session, and one month after the last session. Outcome measures included lesion count, erythema, hyperpigmentation, qualitative global scarring grading, and patient satisfaction.
Two weeks after the first session, there were insignificant differences between both sides regarding lesion count, erythema, hyperpigmentation, and qualitative global scarring grading (p value = 0.8, 0.05, 0.7, 0.1 respectively). Two weeks after the last session, the erythema on the combined side was reduced by a mean of 0.2±0.4 standard deviations (SD) compared to the timolol-only side, with significant differences between both sides (p value=0.03). At the same time, there were insignificant differences between both sides regarding lesion count, hyperpigmentation, qualitative global scarring grading, and patients' satisfaction (p value = 0.1, 0.5, 0.8, 0.3 respectively). Recurrence was detected one month after the last session. No side effects were reported.
The authors write that further and larger studies are still needed to build on these findings.
Challenges to treating acne in transgender Ptx clarified
The treatment of acne in transgender patients may be challenging due to the side effects of hormone therapies, but efficacious treatment options exist, researchers report in the European Journal of Dermatology (Dec. 1, 2024; 34(6):609-615).
In the paper, researchers aimed to identify the specific issues of acne in transgender patients and propose suitable medical care for dermatologists.
A group of five experts on acne reviewed and discussed 68 publications regarding the issue of acne in transgender patients. Key words included “acne+transgender,” “acne+transgender+treatment,” “transgender+skin diseases+treatment,” “transmen+acne+treatment,” and “transwomen+acne+treatment.”
The study authors note that the treatment of acne in transgender patients differs from classic acne treatment in several ways. They note the administration of masculinizing hormones frequently causes moderate to severe acne, which requires the administration of oral treatments involving specific conditions of use, and, conversely, the use of feminizing hormones reduces the risk of more severe forms of acne. However, mild to moderate acne may persist in these patients, requiring topical treatments that may further increase skin dryness and irritation. The risk of acne relapse after stopping treatment may be very high and justifies a maintenance topical treatment. The use of ceramide-enriched emollients is mandatory in all patients.
Real-world clinical experience with clascoterone cream for acne reassuring
Findings from an early real-world clinical experience study support the effectiveness, tolerability, and versatility of clascoterone cream 1% for patients with acne across various clinical and demographic characteristics.
These findings were published in Clinical, Cosmetic, and Investigational Dermatology (Jan. 20, 2025;18:161-167).
This case series included 10 patients with acne vulgaris treated with clascoterone cream 1% as monotherapy or part of a combination treatment program between Aug. 2023 and May 2024.
Clascoterone cream 1% was effective and well tolerated regardless of acne severity, age, gender, and ethnicity. The treatment led to clinical improvement when used as monotherapy, adjunctive treatment in combination with other topical or systemic agents or laser therapy, and as maintenance therapy to prevent relapse of acne.
Moreover, clascoterone also helped to address other concerns in several patients, including hirsutism, hidradenitis suppurativa, retinoid-induced dermatitis, androgenetic alopecia, folliculitis, postinflammatory hyperpigmentation, and laser-induced acne flares.
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