Ig-like ACE2 protein therapeutics: A revival in development during the COVID-19 pandemic

Figures & data

Table 1. Recombinant and Fc-fused ACE2 therapeutics.

Therapeutic	Molecular Format	Most advanced phase	Published data for COVID-19
ACE2-Ig	ACE2 and human IgG1 fusion	Preclinical	Potent in vitro neutralization
STI-4398	ACE2 and human IgG fusion	Preclinical	Under investigation
STI-4920	Anti-spike antibody/truncated ACE2 bispecific fusion	Preclinical	Under investigation
APN-1	Recombinant ACE2	Phase II	Under investigation

Figure 1. Schematic representation of the role of ACE2-Ig regulation of acute lung injury.

ACE2 negatively regulates the function of ACE by converting AT I to AT_1–9 and AT II to AT_1–7. However, SARS-CoV-2 infects ACE2-expressing epithelial and endothelial cells in lung, down-regulating ACE2 expression. ACE2-Ig has potent neutralizing effects to the virus and rebalances the activity of the renin-angiotensin system.