Daptomycin dosing in obese patients: analysis of the use of adjusted body weight actual body weight.

Background: Food and Drug Administration-approved daptomycin dosing uses actual body weight, despite limited dosing information for obese patients. Studies report alterations in daptomycin pharmacokinetics and creatine phosphokinase elevations associated with higher weight-based doses required for obese patients. Limited information regarding clinical outcomes with alternative daptomycin dosing strategies in obesity exists.

Objective: This study evaluates equivalency of clinical and safety outcomes in obese patients with daptomycin dosed on adjusted body weight a historical cohort using actual body weight.

Methods: This retrospective, single center study compared equivalency of outcomes with two one-sided tests in patients with body mass index ⩾30 kg/m who received daptomycin dosed on actual body weight adjusted body weight. The primary outcome was clinical failure. Secondary outcomes included 90-day readmission and 90-day mortality. A combined safety endpoint included creatine phosphokinase elevation, patient-reported myopathy, and rhabdomyolysis.

Results: A total of 667 patients were screened for inclusion; 101 patients were analyzed with 50 in the actual body weight cohort and 51 in the adjusted body weight cohort. actual body weight adjusted body weight; The two regimens were also statistically equivalent for 90-day mortality (6% actual body weight 4% adjusted body weight; = 0.0014 for equivalency). Limitations include single center, retrospective design, and sample size. Daptomycin dosing intensified throughout the study period.

Conclusion: The two daptomycin dosing cohorts were statistically equivalent for both clinical failure and 90-day mortality. More data are needed to assess outcomes with higher (⩾8 mg/kg/day) daptomycin doses in this patient population.