Evaluation of the emetogenic potential of tigecycline 50mg twice daily versus 100mg once daily

Objectives:

Tigecycline is the first-in-class glycylcycline antimicrobial agent used for the treatment of multidrug resistant organisms. Tigecycline is generally well-tolerated with nausea and vomiting being the predominant adverse effects, occurring in up to 26% and 18%, respectively.  The severity of nausea and vomiting seen with tigecycline is dose related. Studies have shown that tigecycline can be administered once daily due to its prolonged half-life. The purpose of this study is to compare the incidence of nausea and vomiting between the administration of 100 mg once daily versus 50 mg twice daily of tigecycline and the utilization of anti-emetic agents.

Methods:

A retrospective, cohort, observational, multicenter study on all patients administered tigecycline from January 1^st 2010 through June 30^th, 2011 admitted to Saint Joseph Hospital, Saint Joseph East and Continuing Care Hospital will be included.  Patients will be stratified into two groups based on the dosing schedule.  Groups will then be evaluated for the incidence of nausea and vomiting. Data will be collected from electronic chart reviews at each site. The study will use categorical analyses including the chi-squared test (χ²) and Fisher’s exact test where appropriate. Continuous data will be tested for significant differences between groups by the Student’s t-test and ANOVA and the Wilcoxon rank sum test.

Results:

A total of 277 subjects were included during the study period. Of the 277 evaluated 79% (n=220) were in the 50mg twice daily group and 21% (n=57) were in the 100mg once daily group. In the twice-daily group, 22% (n=49) were administered prophylactic anti-emetics and 51% (n=110) required additional anti-emetic doses. In the once-daily group, 21% (n=12) were administered prophylactic anti-emetics and 38% (n=20) required additional anti-emetic doses [OR 0.54, 95% CI (0.28-1.03)].   

Conclusion:

Tigecycline once daily was associated with decreased anti-emetic utilization and less incidence of nausea and vomiting as compared to twice daily.