Effect of Optimizing Product Combination on Cost of Anti-Cancer Drug Treatment

Several injectable drugs with different dosages and prices are used in anti-cancer treatments. It is difficult for pharmacists and medical staff to select optimal combinations of products that meet the prescribed dosages at the minimum price. In view of this, we developed a support program for determining such product combinations using NaU DSP®, a processing software. Our program has a simple calculation function that enables us to find the optimal product combinations among the potential matches. We applied it in the analysis of the combined use of the products in cisplatin (2,082 prescriptions), carboplatin (829 prescriptions), methotrexate (1,029 prescriptions), and cytarabine (893 prescriptions) preparations over the period from July 2001 to March 2003 in our hospital.Compared with not using the program, a reduction in the costs of product combinations was achieved for 147 prescriptions (7.1%) with cisplatin, 79 (9.5%) with carboplatin, 192 (19.0%) with methotrexate, and 249 (28.0%) with cytarabine. The reduction in total cost [median (range)/prescription] was ¥1,890 (250-6,445) for cisplatin, ¥2,909 (1,202-19,655) for carboplatin, ¥485 (485-9,146) for methotrexate and ¥2,103 (174-42,000) for cytarabine. The program that we developed can thus be used effectively to find optimal product combinations and reduce drug costs.