**7. AMPs and Fungi**

Fungal infections represent one of the most frequent public health problems [84], also considering the progressive increase in resistance to traditional therapies and the side effects of some antimycotics that limit their use, especially in immunocompromised patients [85].

For this reason, it is necessary to evaluate new molecules to expand our therapeutic options. In our experience, we also evaluated the action of AMPs against fungal infections. Some AMPs show both antibacterial and antibiotic action and can therefore be excellent options in the treatment of mixed infections, allowing them to act on different mechanisms of action than current therapies, which mainly affect sterol biosynthesis [84–89].

#### *7.1. IB-367*

IB-367 is a protegrin with activity against Gram-negative bacteria as well as fungi. In an in vitro study, the efficacy of IB-367 alone and in combination with fluconazole, itraconazole, and terbinafine was evaluated against strains from patients infected with *Trichophyton mentagrophytes*, *T. rubrumand*, and *Microsporum canis*. In monotherapy, the lowest MIC was for terbinafine and itraconazole, but there was a synergy of 35% with IB-367/fluconazole, 30% with IB-367/ITRA, and 25% with IB-367/TERB [88]. This study suggests that IB-367 may be a molecule capable of increasing the efficacy of currently available antifungal therapies.

In addition, IB-367 showed in vitro a rapid fungicidal action against *Candida* spp., both sensitive and resistant to fluconazole. Synergistic action occurred in 41.6% of cases with fluconazole and 44% of cases with amphotericin B, without antagonism [89]. For these reasons, IB-367 is also a very promising molecule for treating candida infections.
