title: Economic burden of adverse events in patients with metastatic renal cell carcinoma.
abstract: BACKGROUND
  Although targeted therapies (ie, tyrosine kinase inhibitors and antiangiogenesis agents) are effective as first-line treatment of metastatic renal cell carcinoma (mRCC), moderate-to-severe adverse events have been reported in clinical trials of these agents. Information concerning the economic burden of these events is limited.
  
  
  OBJECTIVE
  The purpose of this study was estimate the costs associated with adverse events in patients with mRCC receiving selected targeted agents indicated for first-line treatment of this disease.
  
  
  METHODS
  Retrospective study based on health care claims data for patients with mRCC, aged ≥18 years, receiving first-line treatment with targeted therapies. Adverse events of interest included abdominal pain, back pain, diarrhea, dyspnea, extremity pain, fatigue and/or asthenia, hand-foot syndrome, hypertension, lymphopenia, nausea and/or vomiting, neutropenia, proteinuria, and thrombocytopenia. Patients receiving care for these events were identified using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnosis and procedure codes on health care claims. Costs were examined during a 30-day period, beginning with date of first mention of each event; nonevented patients similarly were assigned a shadow index date. We estimated total costs during 30 days after the index date for patients with and without adverse events, excluding the costs of targeted therapy.
  
  
  RESULTS
  Sixty-four percent of patients receiving targeted therapies for mRCC had health care encounters for ≥1 adverse events. Events that occurred with a frequency >20% included severe abdominal pain, back pain, fatigue and/or asthenia, and nausea and/or vomiting, respectively; 10% to 20% of patients had encounters for diarrhea, dyspnea, and extremity pain, respectively. Mean (SD) total costs of care during the 30-day, postevent period were substantially higher among patients with versus without adverse events-$12,177 ($19,621) versus $4070 ($8142). Adjusting for differences in baseline characteristics, the estimated cost difference was $11,373 (95% CI, $5286-$21,419).
  
  
  CONCLUSIONS
  Costs of adverse events are substantial in patients receiving targeted therapies, specifically, sunitinib, sorafenib, or bevacizumab, for mRCC. Efforts to prevent and/or better manage these events may reduce health care costs.
authors.affiliation: Policy Analysis Inc, Brookline, Massachusetts. Electronic address: mhagiwara@pai2.com.
authors.forename: May
authors.initials: M
authors.lastname: Hagiwara
authors.affiliation: GlaxoSmithKline, Philadelphia, Pennsylvania.
authors.forename: Rohit
authors.initials: R
authors.lastname: Borker
authors.affiliation: Policy Analysis Inc, Brookline, Massachusetts.
authors.forename: Gerry
authors.initials: G
authors.lastname: Oster
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020533:Angiogenesis Inhibitors / Q000009:adverse effects* / Q000191:economics; D000970:Antineoplastic Agents / Q000009:adverse effects* / Q000191:economics; D002292:Carcinoma, Renal Cell / Q000188:drug therapy* / Q000191:economics* / Q000556:secondary; D017281:Cost of Illness; D003362:Cost-Benefit Analysis / Q000191:economics; D016208:Databases, Factual; D017048:Health Care Costs; D006801:Humans; D007345:Insurance Claim Review; D007680:Kidney Neoplasms / Q000188:drug therapy* / Q000191:economics*; D008875:Middle Aged; D047428:Protein Kinase Inhibitors / Q000009:adverse effects* / Q000191:economics; D012189:Retrospective Studies; D012720:Severity of Illness Index; D055815:Young Adult
chemical_list: D020533:Angiogenesis Inhibitors; D000970:Antineoplastic Agents; D047428:Protein Kinase Inhibitors
keywords: adverse events; economic burden; metastatic renal cell carcinoma; targeted therapy