General Information

AzaSite is a topical ophthalmic solution of azithromycin formulated in DuraSite (polycarbophil, edetate disodium, sodium chloride). Azithromycin acts by binding to the 50S ribosomal subunit of susceptible microorganisms and interfering with microbial protein synthesis. It is a broad spectrum antibiotic.

AzaSite is specifically indicated for the treatment of bacterial conjunctivitis caused by susceptible isolates of the following microorganisms: CDC coryneform group G, Haemophilus influenzae, Staphylococcus aureus, Streptococcus mitis group, Streptococcus pneumoniae

AzaSite is supplied as a sterile aqueous ophthalmic formulation designed for topical administration. The recommended initial dose of the drug is instill 1 drop in the affected eye(s) twice daily, eight to twelve hours apart for the first two days and then instill 1 drop in the affected eye (s) once daily for the next five days.

Clinical Results

FDA Approval
FDA approval of AzaSite was based on the results of one clinical study. This randomized, vehicle-controlled, double-blind, multicenter trial enrolled subjects with confirmed bacterial conjunctivitis. Subjects received AzaSite or placebo twice daily for the first two days, then once daily on days 3, 4, and 5. Results revealed that AzaSite was superior to placebo on days 6 and 7, with resolution achieved in 63% versus 50% of those treated with placebo (p= 0.03 and the 95% confidence interval around the 13% (63%-50%) difference was 2% to 25%). The microbiological success rate for eradication of the baseline pathogens was 88% for the AzaSite group compared to 66% of those treated with placebo (p<.001, confidence interval around the 22% difference was 13% to 31%).

Side Effects

Adverse events associated with the use of AzaSite may include, but are not limited to, the following:

• Eye irritation
• Burning
• Stinging and irritation upon instillation
• Contact dermatitis
• Corneal erosion
• Dry eye
• Dysgeusia
• Nasal congestion
• Ocular discharge
• Punctate keratitis
• Sinusitis

Mechanism of Action

AzaSite is a topical ophthalmic solution of azithromycin formulated in DuraSite (polycarbophil, edetate disodium, sodium chloride). Azithromycin acts by binding to the 50S ribosomal subunit of susceptible microorganisms and interfering with microbial protein synthesis. Azithromycin has been shown to be active against most isolates of the following microorganisms, both in vitro and clinically in conjunctival infections:CDC coryneform group G, Haemophilus influenzae, Staphylococcus aureus, Streptococcus mitis group, Streptococcus pneumoniae

Literature References

Kuehne JJ, Yu AL, Holland GN, Ramaswamy A, Taban R, Mondino BJ, Yu F, Rayner SA, Giese MJ Corneal pharmacokinetics of topically applied azithromycin and clarithromycin. American journal of ophthalmology 2004 Oct;138(4):547-53.

Breier AR, Garcia CV, Oppe TP, Steppe M, Schapoval EE. Microbiological assay for azithromycin in pharmaceutical formulations. Journal of pharmaceutical and biomedical analysis 2002 Jul 31;29(5):957-61

Additional Information

For additional information regarding AzaSite or bacterial conjunctivitis, please visit the AzaSite web page.