Clinical outcomes and frequency of persistent infection among immunosuppressed patients treated with bebtelovimab for COVID-19 infection at an ambulatory cancer center.

Background: There are limited data on clinical outcomes associated with the use of bebtelovimab for the treatment of coronavirus disease 2019 (COVID-19) among cancer patients. We aimed to define the clinical characteristics and outcomes among patients receiving bebtelovimab as part of the COVID-19 therapeutics program at our cancer center.

Methods: This is a retrospective cohort study of immunosuppressed adult patients who received bebtelovimab at Fred Hutchinson Cancer Center between March 2022, and November 2022. We reviewed medical records to capture the date of the first positive COVID-19 test, clinical characteristics, outcomes, and follow-up COVID-19 testing for 60 days after the first positive. Persistent infection was defined as a positive test beyond day 30; these patients were reviewed beyond day 60.

Results: Among 93 patients who received bebtelovimab, 64 (69%) had hematologic malignancy. Sixty-nine (74%) patients received bebtelovimab within 2 days after diagnosis. Two (2%) patients were hospitalized, none required ICU care, and one patient died on day 52; although it is unknown if death was directly related to COVID-19. Ten (11%) patients had persistent COVID-19 infection; of these, four received additional COVID-19 therapy with either nirmatrelvir/ritonavir or remdesivir, and five out of six patients with sequencing data available had spike protein mutations associated with bebtelovimab resistance.

Conclusion: A coordinated systems-based approach led to prompt initiation of bebtelovimab within two days of testing positive in most patients. We observed few hospitalizations or deaths. Persistent infection was noted in 11% of patients with four requiring additional therapies, highlighting a need for novel strategies to manage immunosuppressed patients.