Candidate: Cas13d Prophylactic Antiviral CRISPR in huMAN cells (PAC-MAN)
Type: CRISPR-based viral inhibition strategy
Status: A team of Stanford researchers that included Lei S. Qi, PhD, and first author Timothy R. Abbott, a PhD student working in Qi’s lab, on April 29 published a study in Cell detailing how Cas13d PAC-MAN effectively degraded RNA from SARS-CoV-2 sequences and live influenza A virus in human lung epithelial cells. The researchers designed and screened CRISPR RNAs (crRNAs) targeting conserved viral regions and identified functional crRNAs targeting the virus—an approach shown to effectively reduce H1N1 influenza A virus load in respiratory epithelial cells.
“The PAC-MAN strategy represents a potentially powerful new approach for inhibiting viral function and replication, and we envision it could be useful for targeting a diverse array of circulating and emergent viral threats,” the author concluded.
Joining Qi as co-corresponding authors were Stanford researchers Marie F. La Russa, PhD, and David B. Lewis, MD. Additional co-authors included Bob Debs, MD, CEO of DNARx, whose HEDGES nonviral gene therapy platform is designed to treat pandemic infections by offering the ability to express one or more therapeutic genes for controlled periods.
The Stanford-DNARx team is among research groups studying forms of Cas-13 as potential COVID-19 therapeutics. A group of Georgia-based researchers on April 24 published a preprint study in bioRxiv detailing their use of Cas13a to target and mitigate influenza virus A (IAV) and SARS-CoV-2 using a synthetic mRNA-based platform: “Our findings demonstrate the applicability of Cas13a in mitigating respiratory infections both in vitro and in a mouse model, paving the way for future therapeutic use.”
COVID-19: 200 Candidates and Counting
To navigate through the >200 potential therapeutic and vaccine options for COVID-19, GEN has grouped the candidates into four broad categories based on their developmental and (where applicable) clinical progress:
● FRONT RUNNER – the most promising therapeutics/vaccines based on clinical progress, favorable data or both.
● DEFINITELY MAYBE – earlier phases with promising partners, or more advanced candidates in development that have generated uneven data.
● KEEPING AN EYE ON… – interesting technology, attracting notable partners, or both, but preliminary data.
● TOO SOON TO TELL – longshots pending additional experimental and/or clinical data.
GEN has also tagged the most common treatment types: