Background Respiratory syncytial virus (RSV) is a major cause of hospitalization for bronchiolitis and pneumonia in infancy. In Japan, limited data are publicly available on RSV epidemiology and clinical characteristics among infants. Methods This retrospective study described RSV incidence, seasonality, patient characteristics, resource use, and clinical outcomes among Japanese children <2 years from January 2017 through December 2018. The RSV cases were identified using the Japanese Medical Data Center database. Results In the database, 9,711 and 8,509 RSV patients <2 years were identified in 2017 and 2018, respectively. Of these, 25% required hospitalization. Ninety percent of hospitalized patients did not have a known RSV risk factor. Nineteen percent of hospitalized patients experienced dehydration, and 12% had acute respiratory failure. Hospitalization lasted 1 week on average and 7% required some type of mechanical ventilation. The peak of hospitalizations occurred at 2 months. The incidence of RSV hospitalization in children <2 years was 23.2 per 1,000 person‐years, which increased to 35.4 per 1,000 for infants <6 months. This age group accounted for 40% of all RSV‐associated hospitalizations among children <2 years. Conclusions Roughly one‐fourth of all RSV patients <2 years were hospitalized. Ninety percent of these did not have an underlying risk condition. This underscores that RSV can cause serious disease among all young children. Three to four out of every 100 Japanese children <6 months were hospitalized for RSV, and this age group accounted for ~40% of all RSV‐associated hospitalizations. Novel and broad‐based RSV prevention strategies, especially those targeting young infants, are needed.

Background:The objective of this study was to conduct a cost-effectiveness analysis of PCV13 vs. PPV23 and no vaccination and PPV23 vs. no vaccination in adults aged ≥ 60 years with underlying medical conditions which put them at an elevated risk of pneumococcal disease in a Japanese healthcare setting. Research design and methods: A natural history model was developed with a life-long time horizon and 1-year cycle length, with microsimulation as a modeling technique. The expected costs from a public payer's and societal perspective, quality-adjusted life-years (QALYs), and prevented cases and deaths caused by IPD (invasive pneumococcal disease) and NBP (non-bacteremic pneumococcal pneumonia) were estimated. Results: In the base-case scenario, the cost per QALY gained from a public payer's perspective for PCV13 vs, PPV23 and no vaccination were 500,255JPY and 1,139,438JPY, respectively, The cost per QALY gained for PPV23 vs no vaccination was 1,687,057JPY. Over the life-long time horizon for 1 million patients, when compared to PPV23, PCV13 resulted in 65 fewer IPD cases, 2,894 fewer NBP cases, and 384 fewer deaths caused by pneumococcal disease. Conclusions: In adults aged 60 years and over with underlying medical conditions, PCV13 was shown to be a more cost-effective alternative to PPV23.

Background Respiratory syncytial virus (RSV) is the major global cause of hospitalization for bronchiolitis and pneumonia in infancy around the globe. In Japan, the occurrence of RSV infection is monitored under the national pediatric sentinel surveillance system. However, this system does not provide detailed information about patient distribution by month of birth and clinical features. We aimed to describe the national epidemiology and clinical features of RSV infection in children &lt; 24 months of age utilizing a nationwide healthcare claims database in Japan. Methods We retrospectively analysed anonymized claims data from the Japan Medical Data Center (JMDC) of medical insurance beneficiaries who had at least one confirmed RSV-related diagnosis by ICD10 codes between January 2017 and December 2018. In children &lt; 24 months of age, the number of patients by age in Japan was estimated using the prevalence of patients in the database and national population data by age. Results In the JMDC database, 9,711 and 8,509 children &lt; 24 months of age had an RSV-related diagnosis in 2017 and 2018, respectively. Of which, 2,473 (25%) and 2,083 (24%) were hospitalized. When extrapolated to the entire Japanese population, an estimated 138,059 and 119,205 RSV-related diagnoses and 33,355 and 27,339 RSV-associated hospitalizations occurred in Japan in 2017 and 2018, respectively. Infants &lt; 6 months of age accounted for between 39% and 42% of total hospitalisations for RSV. A peak in RSV hospitalization was observed at age 2 months. Only 10% of all children &lt; 24 months of age who were hospitalised with an RSV infection had a specific underlying medical condition (preterm infant, bronchopulmonary dysplasia, Down syndrome, chronic heart disease, immunodeficiency). The estimated rate of RSV-associated hospitalization was 35.4 per 1000 population per year among infants &lt; 6 months of age. Conclusion In conclusion, 3 to 4 out of every 100 Japanese children aged &lt; 6 months were hospitalized for RSV. Ninety percent of children &lt; 24 months of age hospitalised with RSV infection did not have a recognised underlying medical condition. The peak of hospitalization for RSV infection occurred at 2 months of age. Thus, broad-based prevention strategies targeting young infants are needed. Disclosures Yasuhiro Kobayashi, MS, Pfizer (Employee, Shareholder) Kanae Togo, PhD, Pfizer (Employee) Yasmeen Agosti, MD, Pfizer (Employee, Shareholder) John M. McLaughlin, PhD, Pfizer (Employee, Shareholder)

Objective: To evaluate healthcare resource use for respiratory syncytial virus (RSV) in Japan. Methods: Using JMDC and Medical Data Vision (MDV) claims databases, we retrospectively evaluated cost and length of hospital/intensive care unit stays in RSV-diagnosed cohorts of infants (<12 months) and older adults (OAs, ≥60 years). We analyzed the usage and costs of palivizumab in infants. Results: Mean costs among those hospitalized were $2823 (USD); $2851; and $6609 (¥131 [JPY]/$) in JMDC-infant (n = 13,752); MDV-infant (n = 22,142); and MDV-OA cohorts (n = 165), respectively. The mean cost was higher in those aged <1 month, with risk factors, and severe RSV disease. Mean cumulative cost of palivizumab prophylaxis in JMDC infant cohort was $6796/year. Conclusion: RSV causes enormous economic burden in infants and OAs.