Imatinib Adherence Lowers Health Care Cost

ATLANTA—Improved compliance with imatinib (Gleevec) therapy for patients with chronic myeloid leukemia (CML) and gastrointestinal stromal tumors (GIST) is associated with decreased total and disease-related health care costs, Henry Henk, PhD, reported at a poster session of the 2006 Annual Meeting of the American Society of Clinical Oncology (abstract 6083).

Dr. Henk, from i3 Innovus, Eden Prairie, Minnesota, and his colleagues from i3 Innovus and Novartis, examined approximately 3 years of claims data from a large US health plan. They identified non-Medicare CML and GIST patients who had continuous pharmacy and medical benefits in the 3 months prior and 12 months following the initiation of imatinib treatment.

Patient compliance was defined by a measure known as the medication possession ratio (MPR)—the total days of imatinib supply in the first year divided by 365.

Total costs were analyzed to determine the relationship between MPR and the first-year of health care costs controlling for relevant variable factors such as age, sex, number of medications, initial starting dose, diagnosis of CML or GIST, and complications due to underlying disease.

Better MPR, Lower Costs

A total of 878 imatinib-treated patients were identified, 413 of whom had at least 15 months of continuous eligibility. Of these, 307 were non-Medicare patients.

The total health care costs per patient in the first year of therapy calculated by MPR groups—less than 50%, 50% to 90%, and 90% to 100%—were $165,116, $54,911, and $42,204, respectively (P < .001) (see Table).

Controlling for variables, a 10% increase in MPR was associated with a 5% decrease in total health care costs (P =.021). The researchers found a similar association between MPR and the specific disease-related costs in these patients.

Although the cost of imatinib therapy can be upward of $40,000 per year, this study demonstrated that improved compliance with imatinib therapy may not only create better clinical outcomes but also decrease total health care costs.

"These findings demonstrate the importance of adherence to imatinib therapy not only for the patients and providers, but for payers as well," Dr. Henk told ONI. Accordingly, Dr. Henk emphasized that physicians should be diligent in encouraging their patients to follow imatinib therapy as prescribed by their physicians.