New antifungal looks safer than liposomal amphotericin B

Micafungin is the newest in a class of antifungal agents called echinocandins. A recent trial showed that it works as well as liposomal amphotericin B, but has a significantly better safety profile when used to treat patients with invasive Candida infections.

The trial, which was sponsored by the manufacturers of micafungin, compared both drugs in 531 adults, most of whom had Candida in their bloodstream. The infection cleared or partially cleared in almost 90% of patients given either drug (181/202 (89.6%) v 170/190 (89.5%)). But those given micafungin had better preserved renal function during treatment than controls. They also had less back pain during infusions (1/264 (0.4%) v 12/267 (4.5%); P=0.003) and fewer electrolyte disturbances. Patients given micafungin were less likely to stop treatment because of serious side effects, although the difference wasn't statistically significant (13/264 (4.9%) v 24/267 (9.0%); P=0.087). Death rates were high in both groups, but most deaths were due to the underlying disease, not the invasive fungal infection.

The researchers conclude that micafungin and liposomal amphotericin B are equally effective. But micafungin is safer, probably because its mechanism of action—inhibiting the synthesis of fungal cell walls—has no impact on human cells.