VYNE Therapeutics Inc. announced new biomarker data from the previously completed Phase 1b trial in patients with nonsegmental vitiligo. The data show that BET inhibitor, VYN201, had a positive effect on multiple disease-associated biomarkers. Positive clinical data from the Phase 1b trial were announced in October 2023.

The trial was a 16-week open-label study assessing the safety, tolerability, pharmacokinetics, and exploratory efficacy of once-daily topical VYN201 in 29 patients with a clinical diagnosis of active nonsegmental vitiligo, in three dose cohorts (0.5%, 1.0% and 2.0% strengths). Enrolled subjects had two, non-facial active vitiligo lesions. One lesion, selected for treatment with VYN201, had skin tissue biopsies taken prior to first application of VYN201 and after 8 weeks of treatment.

Biopsies were analyzed to quantify the effect of VYN201 on specific biomarkers related to inflammation associated with vitiligo, melanocyte proliferation, and melanogenesis. Exploratory data from the 1.0% and 2.0% cohorts showed that VYN201 treatment demonstrated biological activity and a positive effect on certain key biomarkers relevant to vitiligo disease severity and progression. The magnitude of biomarker modulation was more pronounced in the 2.0% dose cohort than in the 1.0% dose cohort, indicative of an emerging dose-response.

Results from the biomarker analyses include the following: Downregulation of Matrix metalloproteinase-9 (MMP-9) levels: VYN201 induced the downregulation of MMP-9 in biopsied lesional skin after 8 weeks of treatment compared to baseline. MMP-9 is an inflammatory biomarker associated with the detachment and subsequent loss of melanocytes from skin in vitiligo and is elevated in patients with vitiligo. At Week 8, there was a median reduction in MMP-9 of 40.8% in lesional skin compared to baseline for subjects in the 2.0% cohort.

Upregulation of melanocyte-related transcription factors(MRTFs): VYN201 induced the upregulation of multiple MRTFs, including SRY-box transcription factor 10 (SOX10), Lymphoid-enhancing factor-1 (LEF1), ß-Catenin and Microphthalmia associated transcription factor (MITF), after 8 weeks of treatment compared to baseline. Each of these markers are linked to the proliferation of melanocytes, recovery in melanogenesis, and subsequent re-pigmentation of skin. In the 2.0% cohort, SOX10, LEF1, ß-Catenin and MITF transcription factors had median increases of 36.1%, 90.2%, 16.5% and 15.2% in their respective expression levels in lesional skin compared to baseline.