Topical antimicrobial peptide omiganan recovers cutaneous dysbiosis but does not improve clinical symptoms in patients with mild to moderate atopic dermatitis in a phase 2 randomized controlled trial.

BACKGROUND: Dysbiosis and colonization with Staphylococcus aureus is considered to play an important role in the pathogenesis of atopic dermatitis (AD). Recovering this dysbiosis may improve AD symptoms. Omiganan is a synthetic indolicidin analogue antimicrobial peptide with activity against S aureus and could be a viable new treatment option for AD. OBJECTIVE: To explore the tolerability, clinical efficacy, and pharmacodynamics of omiganan in mild to moderate AD. METHODS: Eighty patients were randomized to omiganan 1%, 1.75%, or 2.5% or vehicle twice daily for 28 days on all lesions. Weekly visits included clinical scores and microbiological and pharmacodynamic assessments of 1 target lesion. RESULTS: In all omiganan treatment groups, dysbiosis was recovered by reducing Staphylococcus species abundance and increasing diversity. A reduction of cultured S aureus was observed in all omiganan treatment groups, with a significant reduction for omiganan 2.5% compared to vehicle (-93.5%; 95% CI, -99.2 to -28.5%; P = .02). No significant clinical improvement was observed. CONCLUSION: Topical administration of omiganan twice daily for up to 28 days in patients with mild to moderate AD led to a recovery of dysbiosis but without clinical improvement. Therefore, a monotreatment that selectively targets the microbiome does not appear to be a successful treatment strategy in mild to moderate AD.

Pharmacodynamic Effects of Topical Omiganan in Patients With Mild to Moderate Atopic Dermatitis in a Randomized, Placebo-Controlled, Phase II Trial.

Omiganan is an indolicidin analog with antimicrobial properties that could be beneficial for patients with atopic dermatitis. In this randomized, double-blind, placebo-controlled, phase II trial we explored the efficacy, pharmacodynamics, and safety of topical omiganan once daily in 36 patients with mild to moderate atomic dermatitis. Patients were randomized to apply topical omiganan 1%, omiganan 2.5%, or vehicle gel to one target lesion once daily for 28 consecutive days. Small but significant improvements in local objective SCORing Atopic Dematitis index and morning itch were observed in the omiganan 2.5% group compared with the vehicle gel group (-18.5%; 95% confidence interval, -32.9 to -1.0; P = 0.04; and -8.2; 95% confidence interval, -16.3 to -0.2; P = 0.05, respectively). A shift from lesional to nonlesional skin microbiota was observed in both omiganan treatment groups, in contrast to the vehicle group. Thus, treatment with topical omiganan improved dysbiosis in patients with mild to moderate atopic dermatitis, and small but statistically significant improvements in clinical scores were detected. Our findings warrant further exploration in future clinical trials.

Letermovir Resistance Analysis in a Clinical Trial of Cytomegalovirus Prophylaxis for Hematopoietic Stem Cell Transplant Recipients.

BACKGROUND: Letermovir (LET), a cytomegalovirus (CMV) deoxyribonucleic acid (DNA) terminase inhibitor, was recently approved for prophylaxis of CMV infection in adult CMV-seropositive recipients of allogeneic hematopoietic stem cell transplantation. Cytomegalovirus genotyping was performed to identify LET-resistance-associated variants (RAVs) among subjects in a Phase 3 trial. METHODS: The CMV UL56 and UL89 genes, encoding subunits of CMV DNA terminase, were sequenced from plasma collected from subjects with clinically significant CMV infection (CS-CMVi). Novel variants were evaluated by recombinant phenotyping to assess their potential to confer resistance to LET. RESULTS: Genotyping was successful for 50 of 79 LET subjects with CS-CMVi. Resistance-associated variants (encoding pUL56 V236M and C325W) were detected independently in subjects 1 and 3 who experienced CS-CMVi while receiving LET prophylaxis, and 2 other variants (encoding pUL56 E237G and R369T) were detected >3 weeks after subjects 2 and 3, respectively, had discontinued LET prophylaxis and received preemptive therapy with ganciclovir. CONCLUSIONS: The detected incidence of CMV resistance among subjects who received LET as prophylaxis in this Phase 3 trial was low. The LET RAVs that were detected mapped to the CMV UL56 gene at positions associated with reduced susceptibility to LET based on resistance selections in cell culture.

Results of phase 2 trials exploring the safety and efficacy of omiganan in patients with human papillomavirus-induced genital lesions.

AIMS: To assess safety and tolerability and explore pharmacodynamics and efficacy of omiganan in external anogenital warts (AGW) and vulvar high-grade squamous intraepithelial lesions (HSIL). METHODS: Two randomized controlled trials in patients with external AGW and vulvar HSIL were conducted. Patients received topical omiganan 2.5% or placebo gel once daily for 12 weeks with a follow-up of 12 weeks. Safety and tolerability were monitored and pharmacodynamics and clinical efficacy of omiganan were assessed by analysing lesion count, size and viral load. Self-reported pain, itch and quality of life were assessed by an electronic diary and questionnaire. RESULTS: Twenty-four AGW and 12 vulvar HSIL patients were enrolled. All patients had a high treatment adherence (99%). No serious adverse events occurred and all adverse events (n = 27) were mild, transient and self-limiting. The treatment groups were not different in terms of safety and tolerability, lesion count and size, and patient-reported outcomes pain, itch and quality of life. Human papillomavirus load significantly reduced after 12 weeks of treatment with omiganan compared to placebo (-96.6%; 95% confidence interval -99.9 to -7.4%; P = .045) in AGW patients only. CONCLUSION: Topical omiganan appears to be safe in patients with AGW and vulvar HSIL and reduced human papillomavirus load after 12 weeks of treatment in AGW patients.

Evaluation of a novel Chlamydia trachomatis microsphere suspension assay for detection and genotyping of the different serovars in clinical samples.

A novel Chlamydia trachomatis (Ct) microsphere suspension (MS) assay was evaluated for identification of the different serovars, using the same PCR primer set established for the Ct Detection and genoTyping assay. Both assays can detect and identify all 14 major serovars (A, B/Ba, C, D/Da, E, F, G/Ga, H, I/Ia, J, K, L1, L2/L2a, and L3) and one genovariant of serovar J. The probe specificity for the Ct-MS assay was determined using 14 Ct reference strains and 1 clinical isolate from a genovariant of serovar J. Also, the Ct-MS assay and the Ct detection and genoTyping assay were compared in 712 Ct-positive clinical samples. The Ct-MS assay showed a highly specific reaction for all probes with the amplicons of the reference strains, giving a very low background median fluorescence intensity signal (median fluorescence intensity ≤ 10). An excellent overall agreement in the Ct detection (kappa = 0.947, 95% confidence interval, 0.89 to 0.999; McNemar's test, P = 1.000) and the Ct genotyping (kappa = 0.993, 95% confidence interval, 0.977 to 1.000; McNemar's test, P = 0.053) was observed between the Ct detection and genoTyping (DT) assay and the Ct-MS assay. In conclusion, the novel Ct-MS assay permits simultaneous detection and genotyping of Ct serovars, making the Ct-MS assay an excellent high throughput method.