FedExosomes (Pt 3)

The biggest hurdles that exosomes face in the quest to be FDA-approved as a therapeutic are their heterogeneity and the lack of standardization.

In other words, their different sizes and the different protocols that labs use to acquire and load the exosomes creates too much variability to be classified as a standard biologic that can be used in patients.

Let’s break it down further…

First, there is a size problem. One exosome, or ‘package’ might be large and fully loaded. Another may be large, but only a small amount may be inside. A typical FedEx location will boast packages of different sizes, each holding different amounts. Similarly, exosomes come in different sizes, each holding different amounts. It makes it difficult to gauge what is in each. You don’t know until you break it apart. Unfortunately, once its broken, it can’t be reused.

You still get the ten items that you ordered, but its distribution among the packages is rarely equal. And what does that mean for patients? Each recipient cell most likely will not receive the same amount of cargo or instructions needed to induce significant change in the body. And that’s a problem.

Second and lastly, there is protocol chaos. Everyone uses a different technique, or set of techniques, to isolate exosomes, sort exosome sizes, load exosomes with cargo and even to store exosomes for future use. An exosome, or ‘package’ delivered by one lab may differ from another in size preferences, exosome types, number of exosomes etc. This makes it difficult to reproduce the research and validate findings.

Researchers have been working tirelessly to overcome these hurdles. As of the writing of this post, many exosome-based therapeutics have made it to the clinical trial stage but none have yet to be FDA-approved.