Which of the following statements is true for echinocandin drugs?

Echinocandin drugs are a class of antifungal agents that specifically target the synthesis of the fungal cell wall. This action is crucial as the cell wall is a vital structure that provides strength and integrity to the fungal organism. By inhibiting the enzyme glucan synthase, echinocandins prevent the formation of beta-glucan, which is an essential component of the fungal cell wall. This means that echinocandins are particularly effective against certain types of fungi, especially Candida and Aspergillus species, making them an important therapeutic option in the treatment of invasive fungal infections.

The other statements do not accurately reflect the purpose or function of echinocandins. They are not effective against bacterial infections or viruses, as these agents are designed specifically for the treatment of fungal infections. Moreover, they do not solely treat skin-related infections; they are used in more systemic settings and for serious infections. This specificity in targeting fungal cells is what makes echinocandins a vital part of antifungal therapy.