By: Megan Musselman, PharmD, MS, BCPS, BCCCP, MSHP Research & Education Foundation
At the MSHP/ICHP Spring Meeting, the R&E Foundation presented Kat Lincoln, PharmD, BCPS, BCIDP with the MSHP Best Practice Award for her project entitled “Daptomycin weight-based dose optimization”. Olathe Medical Center implemented a dose optimization intervention that utilized adjusted body weight (AdjBW) for patients ≥ 130% of their ideal body weight (IBW) and actual body weight (ABW) for those < 100% IBW. The primary outcome was to determine if implementation of a weight –based dose optimization intervention was effective for the treatment of severe gram-positive infections infection. Secondary outcomes included adverse effects and costs associated with the new dosing protocol. The goals and specific aims for the program were to determine safety and efficacy of dosing daptomycin using AdjBW, decrease cost associated with this dosing strategy, and to develop criteria for use of daptomycin.
At the conclusion of the study, the average patient age was 60 years old with an average ABW of 97.25 kg. Of the patients included, 52.5% had a BMI ≥ 30 kg/m2 and 16.6% had a BMI > 40 kg/m2. The infection classification for daptomycin dosing is found in Table 1. In addition, 20% of patients were readmitted within 90 days due to infectious indications. Severity and type of infection attributed to persistence and higher rates of readmission.
The cost of daptomycin powder for injection is $0.11/mg. Patients with BMI ≥ 30 mg/k2 using AdjBW had a cost savings of $8,000 over 11 months. Patients treated using AdjBW accounted for 53% of orders, but only accounted for 27% of the total cost (Figure 1). The second most common dosing strategy used during the study period was ABW (27.1%) followed by 19.9% of patients being dosed by IBW (Figure 2).
In conclusion from this research project, patients treated using the dose optimization protocol were adequately dosed for treatment and pathogen eradication with minimal 90 day readmission rates. The following daptomycin dosing protocol maintained effectiveness and safety while reducing costs:
• ABW < 100% of patient IBW: Daptomycin dosed using ABW
• ABW ≥ 100-129% of patient IBW: Daptomycin dosed using IBW
• ABW ≥ 130% of patient IBW: Daptomycin dosed using AdjBW
If you have any questions about how Dr. Lincoln implemented her project, please email her at Kathryn.firstname.lastname@example.org.