By Lynda Williams, medwireNews Reporter
medwireNews: Tixagevimab and cilgavimab immunoprophylaxis may help protect patients with haematological malignancies from COVID-19 infection and hospitalisation, suggests a research letter published in JAMA Oncology.
The cohort study reports the outcomes of 204 patients who were eligible for immunoprophylaxis with the two fully human SARS-CoV-2-neutralising monoclonal antibodies due to an increased risk of inadequate response to COVID-19 vaccination.
The patients were enrolled between June and September 2022 and followed-up for 6 months, during which time Omicron variants were prevalent in Italy, write Marco Salvini (ASST Sette Laghi, Varese, Italy) and co-authors.
Overall, 130 patients were given a single pre-exposure prophylactic dose of tixageviamb 150 mg and cilgavimab 150 mg, while 74 patients did not receive the treatment.
The majority of patients in the treatment and control arms had lymphoproliferative disorders or multiple myeloma (77 vs 81%), followed by myeloproliferative neoplasms (19 vs 12%) and acute leukaemia (4 vs 7%). Most patients in the two groups were undergoing active treatment (95 vs 92%), with immunotherapy, targeted therapy, chemotherapy, autologous stem cell transplantation or other treatments.
By March 2023, the rate of breakthrough COVID-19 infection was significantly lower in the patients who did versus did not receive tixagevimab and cilgavimab, at 21% versus 38%.
The COVID-19 incidence was 13.8 per 10,000 person–days with tixagevimab and cilgavimab versus 28.0 per 10,000 person–days without the combination. This gave a significant hazard ratio (HR) of 0.47 in favour of immunoprophylaxis after adjusting for patient age, sex, type of malignancy, receipt of active treatment, current SARS-CoV-2 vaccination status, and whether or not they had received at least three vaccine doses.
Tixagevimab and cilgavimab use also protected patients against severe or critical COVID-19 compared with no use (1.4 vs 4.0 per 10,000 person–days, adjusted HR=0.18) and against the likelihood of requiring a hospital stay (1.3 vs 4.0 per 10,000 person–days, adjusted HR=0.19).
Patients given tixagevimab and cilgavimab who had COVID-19 were ill for a median of 7.5 days and had a median hospital stay of 9.0 days versus 10.0 days and 8.0 days, respectively, for the controls.
Finally, the researchers used propensity score matching for 52 patients given tixagevimab and cilgavimab and 52 controls to mitigate the risk of bias given the study’s lack of randomisation. This sensitivity analysis confirmed that the combination therapy significantly protected against the likelihood of COVID-19 infection with an HR of 0.44, they say.
Noting that “differences in vaccination status” did not seem to affect the study outcomes, the team concludes: “Our findings suggest that prophylactic tixagevimab-cilgavimab may reduce the incidence and severity of COVID-19 and may be a complementary tool to vaccination boosters in patients with [haematological malignant tumours].”
News stories are provided by medwireNews, which is an independent medical news service provided by Springer Healthcare Ltd. © 2024 Springer Healthcare Ltd, part of the Springer Nature Group
JAMA Oncol 2024; 10.1001/jamaoncol.2023.6446