How Do Echinocandin Antifungals Work?

Echinocandins are a new class of antifungals and are water-soluble cyclic lipopeptides (lipid connected to a peptide) that inhibit glucan synthase. They are used to treat invasive fungal infections and show good activity against amphotericin B-resistant and fluconazole-resistant Candida guilliermondii.

Echinocandins work by inhibiting a glucosyltransferase enzyme (1→3)-β-D-glucan synthase, which is essential for the generation of (1→3)-β-D-glucan, an essential component that maintains the integrity of the fungal cell wall. The inability of the organism to synthesize (1→3)-β-D-glucan leads to osmotic instability and cell death. The spectrum of activity of echinocandins is limited to pathogens that rely on these glucan polymers and is less broad than the spectrums of other antifungals such as the polyene or azole agents. Mammalian cells have no cell wall, so echinocandins have very few toxic adverse effects in humans.

Echinocandins exhibit fungistatic activity (inhibit the growth of fungus) against aspergillosis species, whereas they exhibit fungicidal activity (kill parasitic fungi or their spores) against Candida species.

Echinocandin antifungals are administered only by the intravenous route to treat:

• Esophageal candidiasis (the most common type of infectious esophagitis)
• Invasive candidiasis (an infection caused by a yeast [a type of fungus] called Candida)
• Candidemia (a Candida bloodstream infection)
• Invasive aspergillosis (an infection of the pulmonary, parenchyma, which is affected by the growing hyphae of Aspergillus)
• Empirical therapy in febrile neutropenia

Side effects of echinocandin antifungals may include:

• Facial flushing (temporary reddening of the skin because of dilation of blood vessels beneath the skin)
• Severe rash
• Itching
• Fever
• Thrombophlebitis (inflammation of a vein, usually in the leg)
• Hepatitis (inflammation of the liver)

The information contained herein is not intended to cover all possible side effects, precautions, warnings, drug interactions, allergic reactions, or adverse effects. Check with your doctor or pharmacist to make sure these drugs do not cause any harm when you take them along with other medicines. Never stop taking your medication and never change your dose or frequency without consulting your doctor.

Generic and brand names of echinocandin antifungals include:

• Anidulafungin (Eraxis)
• Caspofungin (Cancidas)
• Micafungin (Mycamine)