2022年3月3日，国际权威医学期刊《新英格兰医学杂志》今日发表了预防用单抗nirsevimab III期临床试验的详细结果，nirsevimab是首款只需注射一剂就能为所有婴儿在整个呼吸道合胞病毒（RSV）流行季中提供持续保护的在研长效抗体。该试验入组进入第一个呼吸道合胞病毒流行季的足月婴儿或晚期早产儿（胎龄35周或以上）并达到其主要终点。研究结果显示，与安慰剂相比，单剂nirsevimab保护婴儿免受需要就诊的呼吸道合胞病毒引发的下呼吸道感染（如毛细支气管炎或肺炎）的有效率达到74.5%，具有统计学意义（95% CI 49.6至87.1 ; p<0.001)。
研究者还对III期及IIb期试验中呼吸道合胞病毒导致住院的情况进行了预先设定的合并分析，结果发现在足月儿和早产儿（胎龄大于28周）中，nirsevimab 在建议剂量下降低RSV相关住院发生率的有效率达到77.3% (95% CI 50.3至89.7, P<0.001)。仅在MELODY试验中，研究者已观察到呼吸道合胞病毒感染导致住院的患者人数出现减少（62.1%, 95% CI: -8.6%至86.8%; P=0.07），在nirsevimab组中，994名婴儿中有6名因呼吸道合胞病毒引起的下呼吸道感染而住院，而在496名安慰剂组中有8名因此住院。
美国西北大学范伯格医学院儿科学副教授、美国伊利诺伊州芝加哥市Ann & Robert H. Lurie儿童医院临床与社区试验科学主任William Muller博士表示：随着新冠各项公共防疫政策的逐步放宽，我们看到呼吸道合胞病毒感染出现了反弹，这表明我们需要一种广泛的免疫方法来帮助减轻呼吸道合胞病毒感染对婴儿及其家庭和医疗系统造成的巨大负担。这些令人振奋的研究数据显示，nirsevimab 有望保护所有婴儿不受RSV侵害，这将带来这种疾病预防现状的重大转变。
基于III期和II/III期临床试验以及IIb期临床试验的结果，证实了nirsevimab只需注射一剂就能为所有婴儿在整个RSV流行季中提供持续保护。
赛诺菲疫苗全球研发负责人Jean-François Toussaint表示：“在这三项关键性的后期临床试验中，我们着重研究为所有婴儿提供同类首创的针对呼吸道合胞病毒的预防手段。针对健康晚期早产儿和足月婴儿的III期MELODY临床结果是实现上述目标的重大里程碑。我们很高兴nirsevimab有望成为首个仅需注射一剂就能在RSV流行季为所有婴儿提供持续保护的预防手段。”
有望提供快速保护
Nirsevimab是首款用于保护所有婴儿在第一个呼吸道合胞病毒流行季免受感染的在研长效抗体，目标是通过免疫注射单剂nirsevimab为婴儿提供快速直接的保护。Nirsevimab是首个在III期临床试验中保护婴儿不受RSV侵害的在研预防用单克隆抗体。呼吸道合胞病毒是导致所有婴儿发生下呼吸道感染（包括毛细支气管炎和肺炎）最常见的原因，也是导致婴儿住院的主要原因。
国家呼吸系统疾病临床医学研究中心顾问、首都医科大学附属北京儿童医院、深圳市儿童医院申昆玲教授表示，呼吸道合胞病毒的传染性很强，与新冠病毒相似，所有婴幼儿都有被感染的风险。目前国内在RSV预防和治疗领域，尚无有效的药物或预防手段。期待预防用单克隆抗体nirsevimab的早日上市，填补RSV感染预防领域的一大空白。希望加速国内相关临床试验进展，早日获批进入预防接种体系，让所有中国的婴幼儿受益。”
据悉，预防用单抗nirsevimab已在全球30多个国家开展了临床研究。针对中国健康婴儿的三期临床研究也已启动。全球上市申请已于2022年上半年启动。
赛诺菲疫苗与其合作伙伴阿斯利康正在携手各方，共同推动nirsevimab在中国的研发和上市，保护千万中国婴儿免受呼吸道合胞病毒的侵害。
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