539144
research-article2014
AOPXXX10.1177/1060028014539144Annals of PharmacotherapyClemmons et al
Research Report
Fixed-Dose Rasburicase in Overweight and Obese Patients Versus Normal-Weight Patients
Annals of Pharmacotherapy 2014, Vol. 48(9) 1152–1158 © The Author(s) 2014 Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/1060028014539144 aop.sagepub.com
Amber B. Clemmons, PharmD1,2, Elizabeth Ensley, PharmD1,2, Stephanie Hoge, PharmD1, and Stephen Clark, PharmD2
Abstract Background: Fixed-dose rasburicase (FDR) is common practice in treating hyperuricemia associated with tumor lysis syndrome in adults; however, there is a lack of data regarding the effectiveness of this dosing strategy specifically in the overweight and obese patient populations. Objective: To determine if patient weight per body mass index (BMI) category is associated with failure of initial FDR as defined by the need for additional dose(s) based on a uric acid level (UAL) ≥7.5 mg/dL within 10 days of previous rasburicase administration. Method: Adults who received FDR per institutional guidelines from October 2008 to August 2013 were reviewed. Patients had either a baseline UAL ≥7.5 mg/dL or were considered high risk (leukemia or lymphoma diagnosis with white blood cell count >50 000/mm3 or lactate dehydrogenase level greater than 2 times the upper limit of normal). Patients were stratified by BMI as underweight (50 kg/m2 and 2 of these patients having a BMI >60 kg/m2. Only 1 of these
patients (BMI = 44.9 kg/m2) required a repeat dose of rasburicase.
Discussion To date, no reports have primarily evaluated the efficacy of FDR in the overweight and obese populations. A
Downloaded from aop.sagepub.com at WEST VIRGINA UNIV on June 30, 2015
1156
Annals of Pharmacotherapy 48(9)
Figure 1. Administration of FDR by weight category.a
Abbreviations: FDR, fixed-dose rasburicase; BMI, body mass index. ‡ Includes 3 patients with BMI 40 kg/m2 (morbidly obese).
retrospective study by Vines et al4 of 45 patients (median weight = 78 kg [39.5-153.6 kg]; 58% received a 3-mg rasburicase dose) analyzed the reduction in UAL as a secondary outcome and found no difference between obese and nonobese patients. The authors reported that 5 patients (2 obese, 1 overweight, 2 normal weight) required a repeat dose of rasburicase. Herrington and Dinh15 retrospectively evaluated 34 patients (median weight = 85.3 kg [42-146 kg]; 53% of patients weighed more than 125% of their IBW) who received a 6-mg rasburicase dose and found that 2 patients received a second dose within 12 to 48 hours, both of whom were >125% of their IBW. This study found no difference in their primary end point of decline in UAL for those patients >125% of IBW as compared with those patients who were
research-article2014
AOPXXX10.1177/1060028014539144Annals of PharmacotherapyClemmons et al
Research Report
Fixed-Dose Rasburicase in Overweight and Obese Patients Versus Normal-Weight Patients
Annals of Pharmacotherapy 2014, Vol. 48(9) 1152–1158 © The Author(s) 2014 Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/1060028014539144 aop.sagepub.com
Amber B. Clemmons, PharmD1,2, Elizabeth Ensley, PharmD1,2, Stephanie Hoge, PharmD1, and Stephen Clark, PharmD2
Abstract Background: Fixed-dose rasburicase (FDR) is common practice in treating hyperuricemia associated with tumor lysis syndrome in adults; however, there is a lack of data regarding the effectiveness of this dosing strategy specifically in the overweight and obese patient populations. Objective: To determine if patient weight per body mass index (BMI) category is associated with failure of initial FDR as defined by the need for additional dose(s) based on a uric acid level (UAL) ≥7.5 mg/dL within 10 days of previous rasburicase administration. Method: Adults who received FDR per institutional guidelines from October 2008 to August 2013 were reviewed. Patients had either a baseline UAL ≥7.5 mg/dL or were considered high risk (leukemia or lymphoma diagnosis with white blood cell count >50 000/mm3 or lactate dehydrogenase level greater than 2 times the upper limit of normal). Patients were stratified by BMI as underweight (50 kg/m2 and 2 of these patients having a BMI >60 kg/m2. Only 1 of these
patients (BMI = 44.9 kg/m2) required a repeat dose of rasburicase.
Discussion To date, no reports have primarily evaluated the efficacy of FDR in the overweight and obese populations. A
Downloaded from aop.sagepub.com at WEST VIRGINA UNIV on June 30, 2015
1156
Annals of Pharmacotherapy 48(9)
Figure 1. Administration of FDR by weight category.a
Abbreviations: FDR, fixed-dose rasburicase; BMI, body mass index. ‡ Includes 3 patients with BMI 40 kg/m2 (morbidly obese).
retrospective study by Vines et al4 of 45 patients (median weight = 78 kg [39.5-153.6 kg]; 58% received a 3-mg rasburicase dose) analyzed the reduction in UAL as a secondary outcome and found no difference between obese and nonobese patients. The authors reported that 5 patients (2 obese, 1 overweight, 2 normal weight) required a repeat dose of rasburicase. Herrington and Dinh15 retrospectively evaluated 34 patients (median weight = 85.3 kg [42-146 kg]; 53% of patients weighed more than 125% of their IBW) who received a 6-mg rasburicase dose and found that 2 patients received a second dose within 12 to 48 hours, both of whom were >125% of their IBW. This study found no difference in their primary end point of decline in UAL for those patients >125% of IBW as compared with those patients who were
