A real-world study reports encouraging findings for prophylactic Evusheld in rheumatology patients taking B cell depleting therapies.
A real-world study of immunocompromised patients given prophylactic Evusheld has reported encouraging findings for rheumatology patients taking B cell depleting therapies.
Patients with immune-mediated inflammatory diseases taking rituximab and other B cell depleting therapies are known to have poor responses to vaccination against covid and are also more likely to experience severe covid outcomes, including death.
Evusheld (tixagevimab plus cilgavimab) had been found effective in preventing covid in patients at increased risk of inadequate response to vaccination and was given emergency use authorisation in the US and provisional approval in Australia.
But there were few patients taking immunosuppressive drugs at baseline in the pivotal trial, and few subsequent reports and no real-world studies on the efficacy of Evusheld for pre-exposure prophylaxis in this patient group.
In the current study, published in RMD Open, researchers from the Cleveland Clinic in Ohio, led by Dr Cassandra Calabrese, reviewed patient data from its pharmacy records. They identified 412 patients on B cell depleting therapies or with humoral inborn errors of immunity who’d been given at least one dose of Evusheld, of whom 12 experienced a breakthrough covid infection.
The 12 patients had all had at least one covid vaccine and all were receiving B cell depleting therapy. Vasculitis and rheumatoid arthritis were the most common diagnoses.
One patient of the 12 was hospitalised and required high flow oxygen. Eleven patients had mild cases and recovered at home, with nine of the 11 receiving additional covid treatment (bebtelovimab, sotrovimab and/or nirmatrelvir + ritonavir).
The authors said that while the results were encouraging, the study was limited by small numbers and a lack of a comparator group. The additional treatments also made it difficult to determine which components were responsible for the positive outcomes.
“Collectively, these early data suggest that pre-exposure prophylaxis with tixagevimab/cilgavimab in combination with aggressive outpatient treatment of COVID-19 may be effective in attenuating disease severity in this highly vulnerable population; larger trials with unexposed comparator groups are urgently needed,” concluded the authors, adding that such studies are underway.
In Australia, the National COVID-19 Clinical Evidence Taskforce has provided a consensus recommendation that Evusheld be used in people who are severely immunocompromised. It suggests that, given the paucity of evidence, “rigorous data collection should be undertaken on indications and key outcomes for adults who receive pre-exposure prophylaxis with tixagevimab plus cilgavimab.”
The Taskforce noted that the protection provided by Evusheld wanes over time and recommends providing a repeat prophylactic dose at six months.
The Taskforce also provides a consensus recommendation that Evusheld should be considered for treatment of covid within five days of symptom onset in immunocompromised adults who don’t require supplemental oxygen and are at increased risk of severe disease due to age and other risk factors.
Early supply issues have been resolved, and eligible patients are currently able to receive Evusheld at no cost through the National Medical Stockpile.
Evusheld was up for consideration at the PBAC September intracycle meeting for listing on the PBS for pre-exposure prophylaxis in immunocompromised people aged 12 years and older, which will help ensure ongoing access. The outcome will be announced shortly.
