Trends in Antipseudomonal Agent Use Based on the 2006 to 2015 Sales Data in Japan.

Pseudomonas aeruginosa resistance is a major issue worldwide. Drug resistance is related to inappropriate antibiotic use. Because antipseudomonal agents have a wide spectrum, they must be used appropriately. The purpose of this study was to clarify the trends in antipseudomonal agent use in Japan based on sales data from 2006 to 2015. The total antipseudomonal agent use was increased significantly (r = 0.10, Pfor trend = 0.00040). The proportion of fluoroquinolones use was the highest throughout the year, accounting for 88.6-91.4%. The use of piperacillin/tazobactam significantly increased. The increased use of these drugs may be due to the launch of higher doses and additional indications. On the other hand, for antipseudomonal agents, parenteral carbapenems use was 2.7-3.7%, but it has remained unchanged over the years. In Japan, permit and notification systems have been introduced to prevent the inappropriate use of parenteral carbapenems in medical institutions. It was speculated that these efforts suppressed the inappropriate use of parenteral carbapenems. This study clarified the trend of antipseudomonal agent use in Japan from 2006 to 2015. It is important to continue monitoring antipseudomonal agents use to conduct appropriate antimicrobial resistance measures.

Trends of Antifungal Use Based on Sales Data in Japan from 2006 to 2015.

The detailed epidemiology of invasive mycoses and superficial mycoses has not been clarified in Japan. In addition, treatment options have increased because of novel antifungals and/or guidelines for fungal infection. In the present study, we aimed to clarify the trends of antifungal use in Japan from 2006 to 2015 based on sales data to serve as an alternative indicator of fungal infection trends. We found that the total antifungal use decreased over time (r = -0.057, Pfor trend < 0.0001). Oral and parenteral use significantly decreased by 44.1% (r = -0.056, Pfor trend < 0.0001) and 27.1% (r = -0.0012, Pfor trend = 0.00061), respectively. The trend of antifungal use for superficial mycoses significantly decreased by 49.8% (r = -0.061, Pfor trend < 0.0001). However, the trend of antifungal use for invasive mycoses was significantly increased by 19.9% (r = 0.0032, Pfor trend = 0.00045). In Japan, the increase in the number of immunocompromised patients might be associated with the increase in the frequency of antifungal use for invasive mycoses. This is the first study to clarify the trends of antifungal use in Japan. Further research is needed to establish a continuous surveillance system to compare fungal infections between Japan and the world.

Trends of the Use of Anti-methicillin-Resistant Staphylococcus aureus Agents in Japan Based on Sales Data from 2006 to 2015.

Patterns of the use of anti-methicillin-resistant Staphylococcus aureus (MRSA) agents in Japan might be influenced by the launch of new anti-MRSA agents, the publication of relevant guidelines, and the increase in the number of generic medicines. However, as anti-MRSA agents are included in multiple anatomical therapeutic chemical classifications, such as glycopeptides and aminoglycosides, the trends of the use of individual anti-MRSA agents remain unclear. Here, we aimed to clarify the trends of anti-MRSA agent use in Japan from 2006 to 2015 based on sales data. Total anti-MRSA agent use was found to have significantly increased from 2006 to 2015 (Pfor trend = 0.027, r = 0.00022). Individual trends for vancomycin (VCM), daptomycin, and linezolid (LZD) use showed significant increases, while those for arbekacin (ABK) and teicoplanin (TEIC) showed decreases. In addition, oral LZD use significantly increased, while there was no significant change in intravenous LZD use. The ratio of oral LZD use to total LZD use increased from 25.5% in 2006 to 39.9% in 2015. Meanwhile, TEIC and ABK use decreased, while VCM use increased, following the launch of generic medicines. These results might reflect the status of guideline compliance, the launch of new anti-MRSA agents, and the decline in the sales promotion of the original medicines. It is extremely important to investigate trends for the use of not only different antibiotic groups but also individual antibiotics to develop and implement antimicrobial resistance countermeasures.

The Trend for Antibiotic Use for Clostridioides (Clostridium) difficile Infection in Japan.

In Japan, there is no national surveillance study of Clostridioides (Clostridium) difficile infection (CDI), and details about the epidemiology and treatment status of CDI are unknown. Additionally, clinical practice guidelines (CPGs) for CDI are published by four different institutions. All CPGs recommend that the antimicrobials, vancomycin (VCM) and metronidazole (MNZ), should be selected according to disease severity. However, the trends for VCM and MNZ use in Japan remain unclear. Therefore, this study was aimed at clarifying the secular trends for VCM and MNZ use based on sales data from 2006 to 2015 and discussing its impact on CDI status and drug costs. This is the first study to clarify the antibiotic use trends for CDI treatment. We found that the total use increased over time (r = 0.0013, Pfor trend < 0.0001). While VCM use significantly decreased (r = -0.0003, Pfor trend = 0.0002), MNZ use increased (r = 0.0017, Pfor trend < 0.0001). These results show that although treatment for CDI was in line with CPGs, CDI incidence might be on an increasing trend. Additionally, despite the increased total use, the total drug costs decreased by 55% ($ 25 million) from 2006 to 2015. It was also surmised that CDI treatment in compliance with CPGs would lead to a reduction in drug costs. Hence, to understand the epidemiology of CDI, it is important to continuously investigate the use of drugs used for CDI therapy.