Repeated bolus injections are associated with higher costs and poor compliance and can hinder the implementation of global immunization campaigns. Here, we report the development and preclinical testing of patches of transdermal core–shell microneedles—which were fabricated by the micromoulding and alignment of vaccine cores and shells made from poly(lactic-co-glycolic acid) with varying degradability kinetics—for the preprogrammed burst release of vaccine payloads over a period of a few days to more than a month from a single administration. In rats, microneedles loaded with a clinically available vaccine (Prevnar-13) against the bacterium Streptococcus pneumoniae induced immune responses that were similar to immune responses observed after multiple subcutaneous bolus injections, and led to immune protection against a lethal bacterial dose. Microneedle patches delivering preprogrammed doses may offer an alternative strategy to prophylactic and therapeutic protocols that require multiple injections.

重复推注会导致成本增加和依从性差，并可能阻碍全球免疫运动的实施。在这里，我们报告了经皮核-壳微针贴片的开发和临床前测试——这些微针是通过微塑和排列由具有不同降解动力学的聚（乳酸-共-乙醇酸）制成的疫苗核和壳制造的——用于预编程单次给药可在几天到一个多月的时间内爆发性释放疫苗有效载荷。在大鼠中，微针装载了针对肺炎链球菌的临床可用疫苗 (Prevnar-13)诱导的免疫反应类似于多次皮下推注后观察到的免疫反应，并导致针对致命细菌剂量的免疫保护。提供预编程剂量的微针贴片可以为需要多次注射的预防和治疗方案提供替代策略。