Amoxicillin vs. placebo to reduce symptoms in children with group A streptococcal pharyngitis: a randomized, multicenter, double-blind, non-inferiority trial

Abstract

The efficacy of antibiotic therapy for group A streptococcus (GAS) pharyngitis is debated. The role of antibiotics in preventing complications seems limited, with the main potential benefit being symptom duration reduction. Our study aimed to evaluate whether a placebo is non-inferior to amoxicillin in reducing fever duration. We randomized 88 children between 3 and 15 years of age presenting with acute symptoms of pharyngitis and a positive rapid antigen detection test for GAS to receive 6-day treatment with either placebo (n = 46) or amoxicillin (n = 42). The primary outcome was the difference in fever duration, with a non-inferiority threshold set at 12 h. The secondary outcomes included pain intensity and complications of streptococcal pharyngitis. The mean difference in fever duration between the amoxicillin and placebo groups was 2.0 h (95% CI, - 8.3 to 12.3) in the per-protocol analysis and 2.8 h (95% CI, - 6.5 to 12.2) in the intention-to-treat analysis. Treatment failure was observed in six participants in the placebo group and two in the amoxicillin group (relative risk, 2.15; 95% CI, 0.44-10.57). All patients were identified early and recovered well. There was no clinically relevant difference in pain intensity between groups over the 7 days following randomization, with the largest difference of 0.5 (95% CI, - 0.62-1.80) observed on day 3.

Conclusion: Placebo appears to be non-inferior to amoxicillin in reducing fever duration. Pain intensity and risk of complications were similar between the two groups. These findings support the restrictive antibiotic treatment for streptococcal pharyngitis.

What is known: • Group A streptococcus pharyngitis is a common reason for prescribing antibiotics in pediatric care. • In high-income countries, while antibiotic treatment has not been effective in preventing non-suppurative complications, the primary justification for their use remains the reduction of symptoms.

What is new: • Our results suggest that antibiotics have a limited impact on the duration of fever and the intensity of pain in children with streptococcal pharyngitis. • Considering that suppurative complications can be promptly treated if they arise, we recommend a more judicious approach to antibiotic prescriptions.

Trial registration: The trial is registered at the US National Institutes of Health (ClinicalTrials.gov) # NCT03264911 on 15.08.2017.

Keywords: Amoxicillin; Group A Streptococcus; Placebo; Streptococcal pharyngitis.

Fig. 1

CONSORT diagram

Fig. 2

Mean difference in fever duration between amoxicillin and placebo groups

Fig. 3

Kaplan–Meier survival curve illustrating estimates of the proportion of patients fever-free

Fig. 4

Daily throat pain score in the first 7 days after randomization to amoxicillin or placebo