Despite a substantial increase in neutralizing antibodies against SARS-CoV-2 at days 3 and 8, the monoclonal antibody combination drug Evusheld did not significantly improve hospitalized COVID-19 patients' clinical status or accelerate viral clearance in a phase 3 DISCOVERY European trial.

The results of the trial were described yesterday in a research letter in the Journal of Infection. Evusheld is composed of tixagevimab and cilgavimab (T-C) monoclonal antibodies (mABs), and the study included 399 participants, 214 of whom received Evusheld. A previous study, ACTIV-3-TICO, showed a significant reduction in mortality at day 15 in patients who received Evusheld as an intramuscular injection.

Though there were no major safety events and no increased cardiovascular risks seen in the present trial, researchers found no significant differences in mortality or hospitalization among participants randomized to receive Evusheld and those who received standard care (not remdesivir).

Study conducted during Omicron

Both controls and cases in the trial had an approximate mortality rate of 15% at day 90.

The researchers said the difference seen between the ACTIV trial and DISCOVERY may be due to variants: 40% of COVID infections in the DISCOVERY trial were caused by the Omicron variant, compared to the ACTIV trial, which was primarily during Delta variant dominance.

The SARS-CoV-2 Omicron variant and its multiple sub-lineages have proven to be more evasive than the ancestral strain or Delta variant to vaccines and therapeutic mABs.

"In the ambulatory setting, and while ancestral strains were circulating, the administration of intramuscular T-C to treat SARS-CoV-2 infections significantly reduced the risk of hospitalization and death in patients at risk for disease progression, compared to placebo," the authors wrote, referring to yet another phase 3 trial, called TACKLE. "The SARS-CoV-2 Omicron variant and its multiple sub-lineages have proven to be more evasive than the ancestral strain or Delta variant to vaccines and therapeutic mABs, including T-C."

A successful targeted vaccine campaign prevented a hepatitis A outbreak in a Los Angeles County jail, according to a study yesterday in Morbidity and Mortality Weekly Report.

On May 30, 2023, the Los Angeles County Jail system was notified that an inmate had received a positive hepatitis A test result, the authors said. The person was a 41-year-old food handler who had been first jailed on April 27, 2023, who reported homelessness, injection drug use, and alcohol use disorder on intake. The patient complained of severe abdominal pain and, upon clinical examination, showed signs of jaundice.

An investigation using electronic health records and immunization history helped identify prison contacts who were eligible for hepatitis A vaccination.

Vaccination began within 48 hours

Within 48 hours, 2,766 persons were offered vaccine, and 1,510 (54.6%) agreed to receive it.

"Contacts who were food handlers without confirmed evidence of immunity and who declined vaccination were removed from food-handling duties for the duration of their potential incubation period," the authors wrote.

No additional cases were identified.

"This exposure response highlights the importance of initiating a rapid response to hepatitis A exposure in a jail setting to minimize risk for transmission and help prevent an outbreak," the authors wrote.

"The prompt vaccine rollout likely helped reduce transmission and prevent an outbreak among the LACJ population, and the enhanced surveillance, which included the monitoring of emergency hospital transfers made because of suspicion of acute hepatitis A, helped identify possible secondary cases or clusters needing further investigation"