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Exosome-mediated drug delivery is a promising alternative to conventional drug delivery methods, making rapid strides in the biopharmaceutical industry because of the safety and efficacy advantages exosomes offer as nanocarriers over synthetic nanoparticles. The widely explored concepts of nanomedicine, nucleic acid therapeutics, and cell-free vaccines have bolstered the inclusion of exosomes in delivering newer drug modalities. Non-immunogenicity, biocompatibility, and stability are key features that make exosomes appealing as carriers in the biopharmaceutical sector. As such, microRNAs, small interfering RNAs, CRISPR-Cas9 system, viral vectors, antisense oligonucleotides, messenger RNA (mRNA) vaccines, heteroduplexes, surface antigens, and proteinaceous antibodies have emerged as cargo modalities, either packaged endogenously or exogenously into natural or engineered exosomes.

Exosomes alleviate the issues of stability, low bioavailability, off-targeting, reduced genetic expression, membrane uptake, and cellular degradation facing other nanocarriers in delivering drug modalities. There is a growing body of research and clinical evidence to substantiate the immense value of exosomes in delivering mRNA vaccines, gene editing tools, gene therapy, and disease-related small proteins to treat life-threatening conditions. Exosomes are also used to develop mRNA and other advanced therapeutics formulations that can be administered through more patient-compliant routes, such as oral and intranasal. These extracellular vesicles are surface-engineered to maximize payload efficiency and targeted delivery.