mRNA脂质纳米颗粒生产质量控制关键考虑要点分析及探究

The Analysis and Exploration of Crucial Considerations for Quality Control of Preparation of Lipid Nanoparticle-Messenger RNA

脂质纳米颗粒(LNP)递送技术的突破,推动了RNA疗法的发展,受到了广泛关注。mRNALNP制备是mRNA疫苗从纯化mRNA(原液)到成品(制剂)的生产过程的关键步骤,涉及脂质制备或筛选、mRNA包封/装载、纯化等工序,目前最常用的方法是将水相和脂质成分快速混合的微流控法。基于LNP自组装的特点,本文梳理了微流控条件下mRNA-LNP制备的考虑要点。首先,在制备过程中,各脂质成分比例、脂质和水相的流体动力学、pH值控制、缓冲液的选择与LNP颗粒大小、形态、封装效率和表面电荷等关键质量属性息息相关,需要不断探索mRNA-LNP制备的关键工艺参数和最佳操作范围。其次,还应关注mRNA在被包封到LNP过程中的降解问题,以及生产过程中mRNA原液的任何变化对LNP的影响。此外,本文还提出了针对含有多种mRNA分子的疫苗(如自我扩增型mRNA疫苗和多价疫苗)中LNP制备的考虑要点,以期为国内相关企业在mRNA疫苗制剂生产质量控制方面提供有益参考。

The breakthrough of lipid nanoparticle(LNP) delivery technology has promoted the development of RNA-based therapies, which has attracted extensive attention. The preparation of mRNA-LNP is a key step in the manufacturing process of mRNA vaccine from the bulk purified mRNA(drug substance) to the final vaccine(drug product), which involves lipid preparation and screening, mRNA encapsulation/loading, purification and other processes. The most common method for mRNA-LNP preparation is to rapidly mix the aqueous phase and lipid components by microfluidic technology. Based on the characteristics of self-assembly of LNP, some considerations on the preparation of mRNA-LNP under microfluidic conditions were summarized in this article. Firstly, it was found that some important parameters in process such as the proportion of each lipid component, flow dynamics of the lipid and aqueous phase, pH control,and the selection of buffer would be closely related to the key quality attributions of LNP, for example, particle size, morphology, encapsulation efficiency, and surface charge. Therefore, it is necessary to continuously explore the critical process parameters and their operational ranges optimal for mRNA-LNP. Secondly, specific attention should be given to degradation of the mRNA during encapsulation into the LNP and the impact of any change related to the mRNA drug substance on the critical quality attributes of the LNP. In addition, this article raised some concerns about the preparation of LNP in final vaccines containing multiple mRNA species such as selfamplifying mRNA vaccines and multivalence mRNA vaccines. It is hoped that these considerations will provide useful reference for domestic enterprises in the quality control of drug products of mRNA vaccines.