Budget impact model of tobramycin inhalation solution for treatment of Pseudomonas aeruginosa in cystic fibrosis patients.
BACKGROUND
Pseudomonas aeruginosa (PA) is the most common airway pathogen in cystic fibrosis (CF) patients. The objective of this analysis was to determine the costs of managing PA infection in CF patients with a chronic regimen of tobramycin inhalation solution (TIS).


METHODS
A budget impact model of CF patients was developed to evaluate the costs of TIS from a US managed-care organization (MCO) perspective. The Microsoft Excel model compared TIS treatment plus standard care with standard care alone over a 4-year time horizon and included the cost of drugs, medical care, and annual probabilities of hospitalization and IV anti-pseudomonal (anti-PA) antibiotics administration.


RESULTS
For an MCO with 5,000,000 members, 389 members 6 years of age or older were estimated to have CF, and 218 (56%) had PA infection. Assuming that use of TIS increased from 20% to 25%, the 1-year budget increased $231,251 or from $0.049 to $0.053 per member per month (PMPM). The net drug budget increase was $243,919, while medical costs associated with exacerbation management decreased $12,669 over the first year. Increasing utilization of TIS, from 20% to 40% over 4 years resulted in an incremental overall budget increase of $925,002, a 3% decrease in hospitalizations, and a 4% decrease in administrations of IV anti-PA antibiotics. These reductions translated to a medical care cost saving of $50,676 over 4 years. Limitations of this study include that the clinical data for the model are from clinical trials conducted in 1996 and the estimation of TIS use for CF patients with chronic PA infections can be impacted by TIS adherence.


CONCLUSIONS
Model results suggest that increasing the use of TIS decreases medical care costs due to decreased hospital admissions and the use of IV anti-PA antibiotics at the expense of higher drug costs.
Woodward
Tatia Chay
TC
United BioSource Corporation, Bethesda, MD 20814, USA. tatia.woodward@unitedbiosource.com
Brown
Ruth
R
Sacco
Patricia
P
Zhang
Jie
J
D000280:Administration, Inhalation; D000293:Adolescent; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000191:economics / Q000627:therapeutic use; D002648:Child; D003550:Cystic Fibrosis / Q000188:drug therapy* / Q000191:economics* / Q000382:microbiology; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008329:Managed Care Programs / Q000191:economics; D018803:Models, Economic; D010343:Patient Admission / Q000191:economics / Q000639:trends; D011552:Pseudomonas Infections / Q000188:drug therapy* / Q000191:economics*; D011550:Pseudomonas aeruginosa; D014031:Tobramycin / Q000008:administration & dosage* / Q000191:economics* / Q000627:therapeutic use; D014481:United States
D000900:Anti-Bacterial Agents; D014031:Tobramycin