Amphotericin B
AmBisomePubChem CID 5280965 · 3D model
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Punches holes in fungal cell membranes by grabbing onto a molecule unique to fungi, causing the cell's contents to leak out.
How it works
Amphotericin B works by grabbing onto ergosterol, a fat-like molecule that fungal cell membranes are built from, and poking holes through the membrane. Those holes let charged particles the cell needs to survive leak out, which kills the fungus. The drug prefers ergosterol, but it can also latch onto cholesterol, the similar molecule in human cell membranes, which is part of why amphotericin B can cause side effects like fevers, chills, and kidney strain during treatment. Wrapping the drug in a fatty capsule (liposome), as AmBisome does, helps it reach and penetrate fungal cells while somewhat sparing normal tissue. As with most antimicrobial drugs, resistance can develop with prolonged use.
What it’s used for
AmBisome is used to treat serious fungal infections, including as an early, best-guess treatment for feverish patients with weakened immune systems before the exact fungus causing their infection is identified. It also treats a dangerous brain infection called cryptococcal meningitis in people with HIV, and it treats Aspergillus, Candida, and Cryptococcus infections that haven't responded to older amphotericin B, or in patients whose kidneys can't tolerate the older drug. It's also used for visceral leishmaniasis, a parasitic disease, though the label notes the infection often returns in immunocompromised patients even after initial treatment works. These uses were studied across eleven clinical trials involving more than 2,100 patients.
- Mechanism
- Binds fungal ergosterol, forming membrane pores that cause ion leakage
- Drug class
- Small molecule
- Therapeutic area
- Antifungal