Evaluating Onychomycosis Outcomes 2 Months into an 11-month-long Efinaconazole Regimen: The Role of Optical Coherence Tomography.

BACKGROUND

Onychomycosis affects 43 million people in the United States and Europe. Topical therapies can be effective but require lengthy and costly regimens without an established method for predicting the treatment outcome.

OBJECTIVE

We studied the role of optical coherence tomography (OCT), a noninvasive imaging device approved by the United States Food and Drug Administration, in evaluating onychomycosis treatment outcomes.

METHODS

This investigator-initiated prospective clinical study recruited subjects from two urban medical centers. A total of 34 subjects with mild-to-moderate onychomycosis, confirmed using periodic acid-Schiff (PAS) staining, were treated with topical efinaconazole for 48 weeks, at which time a final PAS result was obtained.

RESULTS

A positive final PAS result was associated with fungal findings on OCT and with nonclearance of fungal findings by week 12. A negative final PAS was associated with the absence of fungal findings by week 12. OCT findings at Week 8 may suggest a 77% chance of mycological nonclearance or 82% chance of clearance. These predictive values are higher than the currently documented mycological cure rate of 54%. Clinical examination data had no predictive value alone or in concert with OCT.

CONCLUSION

We recommend OCT imaging be performed at the end of the second month of treatment to inform shared decision-making regarding whether or not to continue efinaconazole for nine additional months. OCT's ability to evaluate onychomycosis outcome in patients on topical efinaconazole both earlier and more reliably than nonimaging variables may improve the care given to and reduce the cost of onychomycosis for millions of patients.