I have taken a quick look at what EX1 have in regards IP. From reading the prospectus it appear the only significant IP they have is the patent application WO2018112557 [1].
I would be very worried about the prior art in this area. A quick search through pubmed has revealed many publication that have utilised affinity capture and purification of exosomes [see 2,3 as example]. They may be able to get a very narrowly focused patent through, but it won't be hard for anyone to work around it.
1. https://patentscope.wipo.int/search...ueryString=&recNum=75&maxRec=69723603
2. https://www.ncbi.nlm.nih.gov/pubmed/25820723
3. https://www.ncbi.nlm.nih.gov/pubmed/22285593