Extracellular Vesicles Loaded with Long Antisense RNAs Repress Severe Acute Respiratory Syndrome Coronavirus 2 Infection.

Long antisense RNAs (asRNAs) have been observed to repress HIV and other virus expression in a manner that is refractory to viral evolution. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the coronavirus disease 2019 (COVID-19) disease, has a distinct ability to evolve resistance around antibody targeting, as was evident from the emergence of various SARS-CoV-2 spike antibody variants. Importantly, the effectiveness of current antivirals is waning due to the rapid emergence of new variants of concern, more recently the omicron variant. One means of avoiding the emergence of viral resistance is by using long asRNA to target SARS-CoV-2. Similar work has proven successful with HIV targeting by long asRNA. In this study, we describe a long asRNA targeting SARS-CoV-2 RNA-dependent RNA polymerase gene and the ability to deliver this RNA in extracellular vesicles (EVs) to repress virus expression. The observations presented in this study suggest that EV-delivered asRNAs are one means to targeting SARS-CoV-2 infection, which is both effective and broadly applicable as a means to control viral expression in the absence of mutation. This is the first demonstration of the use of engineered EVs to deliver long asRNA payloads for antiviral therapy.