797. Management of Patients with Multiple Clostridioides difficile Infection Recurrences using a Tapered-Pulsed Fidaxomicin Strategy

Background There is a paucity of data assessing outcomes of alternate fidaxomicin strategies in patients with recurrent Clostridioides difficile infection (rCDI). The objective of our study is to evaluate a tapered-pulsed (T-P) fidaxomicin regimen that was administered immediately following a course of CDI treatment with initial symptom resolution in patients with multiple rCDI. Methods We reviewed the characteristics and outcomes of 46 consecutive patients who received T-P fidaxomicin between January 1, 2014-June 30, 2019 in a specialty CDI clinic. The first episode in which fidaxomicin T-P was administered was analyzed. Failure was defined as the persistence of diarrhea and/or the need for additional CDI treatment at any time on T-P fidaxomicin. Sustained clinical cure (SCC) was defined as resolution of diarrhea without recurrence. Recurrence was defined as the return of diarrhea requiring retreatment with CDI therapy after completion of T-P fidaxomicin. Both SCC and recurrence were evaluated at 30 and 90 days after completion of T-P fidaxomicin. Results The mean±SD age of the 46 patients was 63.2±19.9 years, 71.7% were female, and the mean±SD CDI episodes within the past year was 3±1.4 . Most patients (73.9%) had previously failed a vancomycin tapered and/or pulsed regimen. Prior to administering T-P fidaxomicin, a treatment regimen was given to ensure resolution of symptoms. The CDI treatment most commonly used (58.7%) was vancomycin. The T-P fidaxomicin regimen used consisted of 200 mg given once daily for 7 days followed by 200 mg every other day for a median (min-max) duration of 33 (6-120) days. Two patients (4%) failed to respond to T-P fidaxomicin; 34 (74%) and 28 (61%) achieved SCC at 30 and 90 days, respectively. Among the 44 patients that successfully completed the T-P fidaxomicin regimen, recurrence developed in 10 (22.7%) and 16 (36.4%) of patients at 30 and 90 days, respectively, with a median (min-max) time to recurrence of 20 (3-87) days (Figure 1). Four patients with recurrence had received subsequent systemic antibiotics. Figure 1. Course of CDI therapy and follow-up Conclusion A tapered-pulsed fidaxomicin strategy may be effective in patients with multiply rCDI who are refractory to other treatments, including a vancomycin tapered and pulsed regimen. Disclosures Larry H. Danziger, PharmD, Merck (Speaker’s Bureau)