Purpose: This study aimed at identifying prescription trends for the recommended antiemetic therapies before and after the publication of the first guidelines for antiemetic therapy in Japan.
Methods: Claims data of 20 Japanese health insurance societies were analyzed. Claims for patients 18 years old or older who received chemotherapy with high or moderate emetic risk were extracted. The rate of patients who were prescribed the recommended antiemetic drugs was calculated.
Results: From 2005 to 2011, prescriptions for prophylactic antiemetics increased. These prescriptions included the three-drug combination (an NK1 antagonist, a 5-HT3 antagonist, and a corticosteroid) and the two-drug combination (a 5-HT3 antagonist and a corticosteroid). For chemotherapy patients with high emetic risk, these prescriptions increased from 81.1 to 95.5%. For those with moderate emetic risk, these prescriptions increased from 78.5 to 89.9%. After approval of an NK1 antagonist at the end of 2009, the prescription rate for the three-drug combination increased from 37.0% in 2010 to 60.1% in 2011 in the high emetic risk group.
Conclusion: A gradual increasing trend was identified in the rate of prescribing antiemetic drugs from 2005 to 2011. This trend was observed in insurance claims data from a wide variety of health-care providers. However, only 60.1% patients of the high emetic risk group received the recommended three-drug combination in 2011. Further research will be useful to evaluate patients' experiences with their chemotherapy and the effectiveness of the prophylactic antiemetic therapy for cancer treatment and patients' quality of life.