Novavax yesterday announced that the US Food and Drug Administration (FDA) has released a clinical hold on its new drug application for its COVID-flu combination and standalone flu vaccines. In a statement, the company said the step paves the way for it to begin enrolling participants for a phase 3 trial.

The FDA announced the clinical hold on October 16, following a report of a serious adverse event in a participant who received the combination vaccine as part of a phase 2 trial that wrapped up in 2023. The event was initially reported as motor neuropathy, which was later defined as amyotrophic lateral sclerosis (ALS), a condition not known to be immune-mediated or associated with vaccination. The FDA concluded that the event was not related to the vaccine.

Robert Walker, MD, chief medical officer at Novavax, thanked the FDA for its thorough review of additional information it submitted to the agency. "The information provided to the FDA supported our assessment that the serious adverse event was not related to our vaccine. We plan to start our Phase 3 trial as soon as possible."

The candidate vaccines are part of Novavax's portfolio of recombinant protein-based vaccines that use nanoparticle technology and the company's Matrix M adjuvant to boost the immune response.

China has reported seven more H9N2 avian flu infections in humans, mostly involving children and all in people whose symptoms began in September and October, Hong Kong's Centre for Health Protection (CHP) said today in its weekly avian flu update.

Four of the patients are from Hunan province, including a 10-month-old boy, a 1-year-old girl, and two boys ages 3 and 5 years old. One person is a 6-year-old boy from Hubei province, and another is a 7-year-old boy from Jiangxi province.

The only adult patient is a 67-year-old woman from Sichuan province.

Exposures unknown

Exposure sources weren't noted in the report. H9N2 is known to circulate in poultry, especially in Asia, where sporadic infections are reported, mainly in children and mostly mild after exposure to poultry. No sustained transmission has been reported.

China reported its last H9N2 case in September and has now reported 13 cases this year.

An intervention to reduce antibiotic treatment of asymptomatic bacteriuria (ASB) at critical-access hospitals (CAHs) was associated with small but clinically significant improvement, researchers reported yesterday in Infection Control & Hospital Epidemiology.

Misdiagnosis and treatment of ASB—the presence of bacteria in the urine without other signs of infection—is a common practice and major driver of inappropriate antibiotic use in hospitals, particularly CAHs, which are primarily rural and have limited infrastructure for quality-improvement and antibiotic stewardship programs. 

To address the problem, researchers at the University of Washington Center for Stewardship in Medicine created a stewardship collaborative centered on an inappropriate diagnosis of urinary tract infection (ID-UTI) measure that has been shown to reduce ASB treatment in other types of hospitals. 

Reduction in ASB treatment not statistically significant

From October 2022 through July 2023, 1o CAHs participated in the quality-intervention program, which included learning labs, mentoring, and performance reports using the ID-UTI measure, which allowed hospitals to compare rates of ASB treatment. During the study period, ASB treatment at the CAHs fell from 28.4% during the first month to 18.6% during the final month, for an absolute reduction of 9.8%.

After adjusting for hospital clustering, the odds that a case treated for UTI was ASB non-significantly decreased by 6.5% with each additional month (adjusted odds ratio [aOR], 0.935; 95% confidence interval [CI], 0.873 to 1.001). There was no change in antibiotic duration or unjustified fluoroquinolone use.

"Although the reduction in ASB treatment was not statistically significant, the estimated effect size was fairly substantial and thus potentially clinically significant," the study authors wrote, adding that the findings indicate the ID-UTI measure can be implemented in resource-limited settings. 

"Future work over a longer period should be done to ensure that the decrease in overtreatment in ASB can be sustained," they concluded.