Retrospective cohort study comparing the risk of severe hepatotoxicity in hospitalized patients treated with echinocandins for invasive candidiasis in the presence of confounding by indication.

Background: To compare the risk of severe hepatotoxicity with anidulafungin versus caspofungin and micafungin in hospitalized adults.

Methods: This retrospective cohort study combined data from two large US- based hospital electronic medical record databases. Severe hepatotoxicity was a Grade ≥ 3 liver function test (LFT) post-echinocandin initiation. Adjusted incidence rate ratios (IRRs) were estimated for anidulafungin versus caspofungin and micafungin, overall and in patients with normal baseline LFT (Grade 0).

Results: Treatments included anidulafungin (n = 1700), caspofungin (n = 4431), or micafungin (n = 6547). The proportions with LFT Grade ≥ 3 pre-echinocandin initiation were: anidulafungin 40.4% versus caspofungin 25.9% (p <  0.001) and micafungin 25.6% (p <  0.001). Rates of severe underlying diseases or comorbidities were: critical care admissions: 75.3% versus 52.6 and 48.6%; and organ failures: 69.4% versus 46.7 and 51.5%. Adjusted IRRs of severe hepatotoxicity for anidulafungin versus caspofungin and micafungin were 1.43 (p = 0.002) and 1.19 (p = 0.183) overall, and 0.88 (P = 0.773) and 0.97 (P = 0.945) for normal baseline LFT, respectively.

Conclusions: Accounting for confounders, severe hepatotoxicity risk was not significantly different across echinocandins in this real-world head-to-head study. Anidulafungin was used more frequently in patients with more comorbidities. Those with normal baseline LFT (least susceptible to confounding by indication), showed no elevated hepatotoxicity risk for anidulafungin.