471. Comparison of Outcomes for Obese and Non-Obese Patients Receiving Micafungin 100 mg Daily for Candidemia

Abstract

Abstract Background Echinocandins, such as micafungin, are first-line agents for the treatment of candidemia. Researchers have questioned the adequacy of the standard 100 mg dose for all patients, as certain characteristics such as obesity can significantly alter the pharmacokinetics of this agent. Prior data have shown obese patients may be less likely to achieve the pharmacodynamic targets shown to be associated with clinical success. The purpose of this study is to compare clinical outcomes for obese and non-obese patients receiving standard dosing of micafungin. Methods This is a multi-center, retrospective study conducted at two large academic hospitals. All adults admitted with a positive blood culture for Candida spp. between January 1st 2017 and December 31st 2021 were reviewed for inclusion. Patients who received > 1 dose of micafungin were designated as either obese (BMI ≥ 30 kg/m2) or non-obese (BMI < 30 kg/m2). Patients who received combination antifungal therapy or had subsequent episodes of candidemia were excluded. Results One hundred and eighty-five of 248 patients were included. Fifty-six (30.3%) patients were obese and 129 (69.7%) were non-obese. Most were critically ill (55.1%), middle-aged (median 60 years), Hispanic or Latino (52.7%) and male (57.8%). Patients received micafungin 100 mg IV daily for a median of 6 (IQR 3-11.5) days. Obese patients had a higher Charlson Comorbidity Index of 4.5 (IQR 3-6.8) compared to 4 (IQR 2-6) in non-obese patients. Critically ill obese and non-obese patients had median Sequential Organ Failure Assessment scores of 10 (IQR 6.75-11.5) and 9 (IQR 4-12), respectively. Clinical and microbiologic failure at day 14 were numerically higher in obese patients ([44.6% vs 32.3%; p = 0.13] and [19.6% vs 10.1%; p = 0.10], respectively), while in-hospital and 30-day mortality were significantly higher in the obese population ([39.3% vs 22.5%; p = 0.03] and [44.6% vs 27.1%; p = 0.03], respectively). Conclusion Obese patients treated for candidemia with micafungin 100 mg IV daily had a significantly higher in-hospital and 30-day mortality. Clinical and microbiological failure followed a similar trend, without meeting statistical significance. Additional studies are warranted to determine whether higher doses of micafungin may improve outcomes in obese patients. Disclosures All Authors: No reported disclosures.