215 Background: Docetaxel is standard of care among late-stage prostate cancer patients. We analyzed patterns of health care resource utilization (RU) among patients before and after exposure to docetaxel using a large commercial claims database. Methods: A random sample of patients (N = 336) with a diagnosis of prostate cancer (ICD 9 code: 185.X) and a claim for docetaxel (2003–2009) was identified from the PharMetrics database, a nationally representative, non-payer-owned integrated commercial U.S. claims database. All patients had ≥ 12 months of enrollment prior to initiation of docetaxel. Patients were followed from their first docetaxel claim until lost to follow-up or June 30, 2009 (censored). RU was defined as all-cause hospitalization, ER, physician, and ambulatory visits. Incidence rates were derived. Results: Mean age of patients was 67.9 years (SD 10.6); mean number of docetaxel prescriptions was 9.9 (SD 10.3). Mean time to study end/lost to follow-up was 15.41 (SD 12.49) months from the index date. The table shows health care RU for the 12 months before, and over the follow-up period after docetaxel initiation. Hospitalizations, ER, physician, and ambulatory visits were significantly higher in the follow-up period. The average length of hospital stay was significantly longer after docetaxel treatment (8.2 vs 5.5 days). Prior to docetaxel, two-thirds of the patients were on hormonal therapy; 51% on analgesics, and 31% on bisphosphonates. After docetaxel, the proportions were 62%, 58%, and 54%, respectively. Conclusions: The significantly higher RU with disease progression in prostate cancer patients suggests a need for new treatment options that can effectively manage and improve patient outcomes. [Table: see text] [Table: see text]