Abstract：
Pneumococcal disease, presenting as invasive pneumococcal disease (IPD) or community-acquired pneumonia (CAP) is an important cause of illness and hospitalisation in the elderly. To reduce pneumococcal burden, since 2003, 65-year-olds in England have been offered a 23-valent pneumococcal polysaccharide vaccine (PPV23). This study compares the impact and cost-effectiveness (CE) of vaccination with the existing PPV23 vaccine to the new 15-and 20-valent pneumococcal conjugate vaccines (PCV15 and PCV20), targeting adults aged 65 or 75 years old. We developed a static Markov model for immunisation against pneumococcal disease, capturing different vaccine effectiveness and immunity waning assumptions, projecting the number of IPD/CAP cases averted over the thirty years following vaccination. Using an economic model and probabilistic sensitivity analysis we evaluated the CE of the different immunisation strategies at current vaccine list prices and the willingness-to-pay at a median threshold of £20,000/QALY and an uncertainty threshold of 90% of simulations below £30,000/QALY. PCV20 averted more IPD and CAP cases than PCV15 or PPV23 over the thirty years following vaccination: 353(360), 145(159) and 150(174) IPD and 581(673), 259(485) and 212(235) CAP cases at a vaccination age of 65(75) under base vaccine effectiveness assumptions. At the listed prices of PCV20 and PPV23 vaccines as of May 2023, both vaccines were cost-effective when vaccinating 65- or 75-year-olds with an ICER threshold of £20,000 per QALY. To achieve the same cost-effectiveness as PPV23, the additional cost of PCV20 should be less than £44(£91) at an ICER threshold of £20,000/QALY (£30,000/QALY) if vaccination age is 65 (or £54(£103) if vaccination age is increased to 75). We showed that both PPV23 and PCV20 were likely to be cost-effective. PCV20 was likely to avert more cases of pneumococcal disease in elderly adults in England than the current PPV23 vaccine, given input assumptions of a higher vaccine effectiveness and slower waning for PCV20.
摘要：
肺炎球菌病,出现侵袭性肺炎球菌病(IPD)或社区获得性肺炎(CAP)是老年人患病和住院的重要原因.为了减轻肺炎球菌的负担，自2003年以来,英国65岁的青少年接种了23价肺炎球菌多糖疫苗(PPV23).这项研究比较了现有PPV23疫苗与新的15价和20价肺炎球菌结合疫苗（PCV15和PCV20）接种疫苗的影响和成本效益（CE）。针对65岁或75岁的成年人。我们开发了一个用于肺炎球菌疾病免疫的静态马尔可夫模型，捕获不同的疫苗有效性和免疫力下降的假设，预测接种疫苗后30年来避免的IPD/CAP病例数量。使用经济模型和概率敏感性分析，我们评估了当前疫苗标价下不同免疫策略的CE，以及在20,000英镑/QALY的中位数阈值和90％的不确定性阈值下的支付意愿低于30,000英镑/QALY的模拟。在接种疫苗后的30年中，PCV20比PCV15或PPV23避免了更多的IPD和CAP病例：353（360），145（159）和150（174）IPD和581（673），在基础疫苗有效性假设下，接种年龄为65（75）的259（485）和212（235）例CAP病例。根据2023年5月PCV20和PPV23疫苗的上市价格，这两种疫苗在为65或75岁的年轻人接种疫苗时具有成本效益，每个QALY的ICER门槛为20,000英镑。为了实现与PPV23相同的成本效益，如果疫苗接种年龄为65英镑，则在ICER阈值为20,000英镑/QALY（30,000英镑/QALY）时，PCV20的额外成本应低于44英镑（91英镑）（如果疫苗接种年龄增加到75英镑，则为54英镑（103英镑））。我们发现PPV23和PCV20都可能具有成本效益。与目前的PPV23疫苗相比，PCV20可能在英格兰老年人中避免更多的肺炎球菌疾病病例。在输入假设的情况下，PCV20的疫苗效力更高，下降速度更慢。
