rationale. Numerous studies have presented compelling data
on the efficacy and tolerability of antifungal therapy for onychomycosis.
To our knowledge only one study has looked at the
benefits of treating co-existing tinea pedis on onychomycosis
outcomes, and this was a post hoc analysis of two large studies
treating mild to moderate toenail onychomycosis with efinaconazole
topical solution, 10%.22
Overall, 21.3% (352/1655) of onychomycosis patients reported
interdigital tinea pedis at baseline, a figure very similar to
that reported in previous surveys.7 Although the studies were
not designed to investigate tinea pedis treatment, investigator
approved topical antifungals were allowed. Almost two
thirds of patients with onychomycosis also had their co-existing
tinea pedis treated.
In reviewing all primary and secondary endpoints, treatment
of mild to moderate onychomycosis with efinaconazole topical
solution, 10% was much more effective when co-existing tinea
pedis was also treated.
Pooled data from the two studies have already been reported.
23 Complete cure rates of 18.5% and mycologic cure rates
of 56.3% were seen at week 52, compared with 4.7% and
16.6% with vehicle (both P<.001). In a post hoc analysis of patients
with co-existing tinea pedis, when the tinea pedis was also treated, complete cure rates with efinaconazole were
29.4% (Figure 1a), and mycologic cure rates 56.2%. When
tinea pedis was not treated, complete cure rates were 16.1%
(Figure 1b), and mycologic cure rates 45.2%. Interestingly, in
the vehicle group where co-existing tinea pedis was not treated
complete cure rates remained zero throughout the study
(Figure 1b).22 The number of patients achieving complete/almost
complete cure was also greater if their co-existing tinea
pedis was treated, with more than one third of patients having
an affected target toenail involvement of ≤5% at week 52
(Figure 2). This post hoc analysis had some limitations. The
studies were not designed to investigate both diseases and
their treatment. There is no information about the severity of
tinea pedis or how successfully it was treated. Nevertheless,
it does provide important data to support the importance of
treating both diseases.
