DermTech, Inc.’s Melanoma Test (DMT) performed well in a real-world clinical setting, the Company reports.
The test assesses pigmented skin lesions, moles or dark skin spots for melanoma. In particular, the PLA detects expression of the LINC00518 (LINC) and preferentially expressed antigen in melanoma (PRAME) genes using reverse transcription-polymerase chain reaction (RT-PCR). The Company introduced an add-on assay to the PLA in 2021, which is designed to identify the presence of mutations in TERT gene promoter region using DNA sequencing.
The Trust 2 Study, initiated in 2021, enrolled more than 20,000 patients tested with the DMT in a real-world clinical setting. Follow-up evaluations occurred for more than 5,000 tested lesions, with median and mean follow-up durations of 348 days and 337 days, respectively. Follow-up evaluations included pathology diagnoses for lesions that were biopsied, and visual re-examination for lesions that were monitored rather than biopsied, in which the lesion was classified as either stable/unchanged or changed in a manner concerning for melanoma.
The Trust 2 Study results demonstrated a negative predictive value (NPV) of 99.7% for the foundational gene expression assay component of the DMT. The NPV of 99.7% was observed (rather than calculated from an assumed prevalence) and was associated with a narrow 95% confidence interval of 99.5% to 99.9%. The Trust 2 Study results also included a sensitivity of 95.8%, a specificity of 69.4% and a positive predictive value (PPV) of 13.4%.
The Trust 2 Study results further validate the 99% NPV observed in a similar real-world study (Trust 1) published in 2021, which evaluated the tested lesions of more than 1,500 patients.
“The Trust 2 Study illustrates that a high NPV test such as the DMT can allow physicians to confidently rule out melanoma for their patients,” says Maral K. Skelsey, MD, Clinical Professor of Dermatology at Georgetown University’s Medical School and one of the lead Trust 2 Study investigators, in a news release.
“The Trust 2 Study results reaffirm the DMT’s real-world clinical utility to rule out melanoma with a NPV that is higher than other currently available methods,” adds Loren Clarke, MD, chief medical officer, DermTech. “Importantly, for clinicians and patients, a high NPV delivers assurance that a suspicious pigmented lesion which tests negative is unlikely to be a melanoma. As a non-invasive test that has demonstrated an NPV of 99% or higher in multiple, large studies, the DMT provides actionable genomic information for a suspicious pigmented lesion that a clinician may be hesitant to biopsy for a variety of reasons.”
