2110. Treatment of Coccidioidomycosis with Isavuconazole

Background There are limited prospective data available to guide the management of severe coccidioidomycosis. In particular, the treatment of disseminated coccidioidomycosis often requires extended courses of antifungal therapy, for which there are often intolerable side-effects, toxicities, and failures. In recent years, newer oral triazole antifungals with in vitro activity against Coccidioides have become available, but data are lacking on their efficacy in coccidioidomycosis. Isavuconazole lacks many of the toxicities of older triazole antifungals, such as QT prolongation and certain key drug interactions, making it an appealing option in selected patients. Methods Based on pharmacy prescription history at two federal facilities in southern California, we identified adult patients with coccidioidomycosis who received isavuconazole from 2017 to 2019. Patient records were reviewed to identify age, sex, ethnicity, sites of infection, prior antifungal therapy, indication for switch to isavuconazole, duration of follow-up, and outcomes. Results 12 patients were identified between the ages of 36 and 86 years; 3 were women. 6 were of Pacific Islander descent, 4 were African American, 1 European-American, and 1 Latino. 6 (50%) had significant pre-infection comorbidities. 8 (67%) had evidence of extrapulmonary dissemination, including 1 patient with meningitis. All but one had received prior treatment with other azoles; two had previously been treated with amphotericin B. Six (50%) were switched to isavuconazole due failure or progression of disease on prior therapy; 3 (25%) due to drug toxicity; and 2 (17%) due to drug interactions. Seven (58%) patients improved on isavuconazole; 4/12 (33%) were stable; one developed hepatotoxicity but improved on posaconazole, and one patient deteriorated. Conclusion Isavuconazole appears to be a promising agent for the treatment of coccidioidomycosis. Long-term follow-up will be required to assess the risks of toxicity, disease progression, or relapse. For patients who are clinically stable but with an extensive disease burden or toxicity from older agents, isavuconazole may present an amphotericin-sparing option. Disclosures All authors: No reported disclosures.