Antibiotic-resistant acne: getting under the skin

Efficacy and Safety of VB-1953 Topical Gel in Non-Responder Acne Patients with Clindamycin-Resistant Cutibacterium acnes

BACKGROUND AND OBJECTIVES

The emergence of resistant strains of Cutibacterium acnes can limit the efficacy of currently approved antibiotics for acne. VB-1953 is a next-generation antibiotic that exerts a bactericidal effect on resistant C. acnes. In this study, we investigated the safety, tolerability, and efficacy of VB-1953 topical gel in patients with moderate to severe acne having clindamycin-resistant C. acnes.

METHODS

An investigator-initiated, open label, single-arm clinical study was conducted in patients with moderate to severe facial acne vulgaris showing poor or no response to previous clindamycin treatment. Nineteen subjects were enrolled in the study based on laboratory screening for the presence of clindamycin-resistant C. acnes in acne swab samples collected from patients. VB-1953 2% gel was applied on the entire face twice daily over 12 weeks. The primary efficacy endpoints were absolute changes in inflammatory and noninflammatory lesion counts from baseline at week 12, while the secondary efficacy endpoint was the proportion of subjects achieving Investigator Global Assessment success (score of 0 or 1) or a grade 2 or higher improvement from baseline at week 12. The presence and severity of local skin reactions (erythema, edema, scaling/dryness, burning/stinging, pruritus) were evaluated for safety. Additionally, the detection and quantification of drug-resistant C. acnes strains were performed in the laboratory using acne swab samples collected from patients.

RESULTS

The occurrence of treatment-emergent adverse events or changes in vital signs, physical examinations, and urinalysis for any of the patients during the course of the entire study were clinically insignificant. Topical application of 2% VB-1953 topical gel resulted in a significant reduction of mean absolute inflammatory and noninflammatory lesion counts by 53.1% and 52.2%, respectively (p < 0.0001 for both), with an Investigator Global Assessment success of 26.3% at week 12 compared with baseline. Resistant bacteria were reduced by (94.3 ± 1%; p < 0.05) within 12 weeks of treatment with VB-1953.

CONCLUSION

These results indicate that VB-1953 topical gel can be a safe and effective therapy for moderate to severe acne with underlying resistant C. acnes in subjects who had not responded to previous antibiotic treatments.

Clinical Pharmacokinetics, Safety and Exploratory Efficacy Study of a Topical Bactericidal VB-1953: Analysis of Single and Multiple Doses in a Phase I Trial in Acne Vulgaris Subjects

BACKGROUND AND OBJECTIVE

Cutibacterium acnes is a key pathogenic factor in the development of acne vulgaris. Topical and oral antibiotics play a pivotal role in effective management of the disease. The emergence of resistance to the currently available antibiotics poses a serious set-back to this algorithm, and the reduced arsenal can diminish the efficacy of treatment. A novel formulation of VB-1953 (2%) topical gel has been developed with dual mechanism of action and bactericidal activity, unlike the currently approved antibiotics, which are bacteriostatic agents, targeting acne vulgaris. The objective was to check the clinical pharmacokinetics, safety and tolerability of single and multiple doses of VB-1953 in adult subjects with facial acne vulgaris, when applied twice daily (every 12 h) for about 15 days starting from Day 1, morning dose until Day 15, morning dose.

METHODS

This was a Phase 1 open-label study of VB-1953 for evaluation of pharmacokinetics, safety, tolerability and exploratory efficacy in otherwise healthy adult patients with moderate-to-severe facial acne vulgaris. The 12 subjects (aged 18-45 years) enrolled for the study applied VB-1953 (2%) gel twice daily for 15 days on the entire face every 12 h starting from Day 1 morning to Day 15 morning. Pharmacokinetic assessment was evaluated by sequential blood collection and safety was measured by assessments of local skin reactions (LSRs).

RESULTS

Plasma concentrations of VB-1953 indicate a low systemic exposure. By Day 2, steady-state was achieved and by Day 15 maximum plasma concentration (C_max) was 0.4640 ng/mL indicating about twofold increase upon multiple dosing. Changes in safety parameters (vital signs, electrocardiogram, physical examinations, hematology, chemistry, urinalysis) were clinically insignificant.

CONCLUSION

VB-1953 topical gel appears to be safe for use in adults with facial acne vulgaris and may offer new advances as a topical antibiotic agent for the disease.

A Rationally Designed Multifunctional Antibiotic for the Treatment of Drug-Resistant Acne

Acne is a multifactorial skin disease, underpinned by colonization of Propionibacterium acnes and inflammation. The emergence of resistant P. acnes strains has affected the current acne treatment algorithm. This setback served as an impetus for rationally designing a library of next-generation antibiotics that exhibit a bactericidal effect on resistant P. acnes and exert an immunomodulatory function to reduce inflammation. In silico screening showed that one of the molecules, VCD-004, exhibits improved mode of binding to bacterial DNA gyrase. VCD-004 shows high potency against clinical isolates of resistant P. acnes and excellent efficacy in vivo. Furthermore, VCD-004 exhibits a superior mutant prevention index, suggesting that it impedes the development of resistance better than clindamycin. Additionally, it shows optimal skin penetration and has a potent anti-inflammatory effect via reduction of proinflammatory cytokines (IL-6) independent of its antibacterial action. VCD-004 affects P. acnes-induced nuclear accumulation of NF-κB in THP-1 cells. The in vitro viability of human keratinocytes in the presence of VCD-004 indicates a desirable therapeutic window for topical use. Such rationally designed bactericidal and immunomodulatory dual pharmacophore-based lipophilic molecule(s) can emerge as the next-generation topical therapy for acne with underlying resistant P. acnes etiology.