Local Budesonide Therapy Not Efficacious Against COVID-19-Related Hyposmia

Local budesonide therapy is not efficacious for the treatment of persistent COVID-19-related hyposmia, according to study findings published in the International Journal of Infectious Diseases.

Researchers in Paris, France conducted a 2-center, open-label, randomized controlled, superiority trial to assess the efficacy of local budesonide plus olfactory rehabilitation in participants with persistent hyposmia due to nonsevere COVID-19 infection. Eligible participants were older than 18 years with hyposmia persisting 30 days after the onset of symptoms suggestive of COVID-19 infection. Participants (N=123) were randomly assigned 1:1 to receive intranasal treatment with either normal saline and budesonide (treatment) or normal saline alone (control), administered in the morning and evening for 30 days. Participants in both groups also underwent olfactory rehabilitation twice daily.  

The researchers measured olfactory improvement through the ODORATEST, an assessment to determine olfactory threshold for 5 pure, easily-recognizable odorants. The primary endpoint was the percentage of participants with an ODORATEST score improvement of more than 2 points after 30 days of treatment.  

Among participants in the treatment and control groups, the mean ages were 40.1 and 40.6 years, 67.7% and 67.2% were women, and 8.2% and 23% had olfactory symptoms concomitant to other COVID-19 symptoms, respectively. Rhinologic history was noted in 19.7% of participants in the treatment group and 34% of those in the control group, of whom 66.6% and 87.6% reported allergic rhinitis, respectively.

In the final analysis, only 2 (3.3%) participants in the treatment group showed an improvement of more than 2 points on the ODORATEST after 30 days, whereas those in the control group showed no improvement. Fisher exacting testing showed no significant between-group differences.

The treatment and control groups had 55 and 54 participants, respectively, who did not completely recover after 30 days. The researchers noted no significant between-group differences in ODORATEST scores and olfactory capacities after 30 days.

The researchers also noted sub-par treatment adherence, with correctly performed nasal irrigation between baseline and day 30 reported by 48% of treatment group participants and 50% of control group participants.

Treatment-related adverse effects were reported by 3 participants in each group. In regard to severe adverse effects, 1 control participant experienced severe pharyngitis requiring hospitalization and surgical repair for phlegmon, and 1 treatment participant had semi-recent cerebral ischemia detected on magnetic resonance imaging.

Limitations of this study include the enrollment of participants from only 2 sites, the uncommon methodology, and the delay in budesonide initiation until 30 days after COVID-19 onset. Moreover, the higher rate of allergic rhinitis in control participants may have introduced bias.

According to the researchers, “The results of this study strengthen the hypothesis that one month after onset of infection, cellular damage is already occurring and that the use of an anti-inflammatory does not modify the course of olfactory impairment.”

This article originally appeared on Infectious Disease Advisor