Natamycin superior to voriconazole for Fusarium keratitis

This phase 3, double-masked, multicenter, prospective study found that natamycin was associated with significantly better clinical and microbiological outcomes than voriconazole for smear-positive filamentous fungal keratitis, with much of the difference attributable to improved results in Fusarium cases.

The authors randomized 323 patients to voriconazole (1%) or natamycin (5%) applied topically every hour while awake until re-epithelialization, then four times daily for at least three weeks.

Natamycin-treated cases had significantly better BCVA at three months than voriconazole-treated cases. Natamycin-treated cases were also less likely to have perforation or require therapeutic penetrating keratoplasty. Fusarium cases fared better with natamycin than with voriconazole, while non-Fusarium cases fared similarly with each.

The authors note that natamycin was significantly more successful at clearing culture positivity after six days: Fewer than 10 percent of initially culture-positive patients in that group had a positive culture at six days, compared with more than 50 percent of patients randomized to voriconazole.

They conclude that together with visual acuity and perforation or transplant results, these findings suggest that topical voriconazole is substantially less effective at clearing Fusarium species and should not be considered appropriate monotherapy for Fusarium keratitis.