Irreversible HIV-1 Inactivation Employing a Small Molecule Dual-Action Virolytic Entry Inhibitor Strategy

The design, synthesis and validation of a family of small molecule “Dual-Action Virucidal EntryInhibitors” (DAVEIs) has been achieved that result in irreversible lytic inactivation of HIV-1 virions. These constructs contained two functional components that endow the capacity to bindsimultaneously to both the gp120 and gp41 subunits of the HIV-1 Envelope glycoprotein (Env). One component is derived from BNM-III-170, a small molecule CD4 mimic warhead that binds togp120. The second component, a Trp3 peptide, is a 9-amino acid segment based on the gp41 Membrane Proximal External Region (MPER) that has been proposed to bind to the gp41 MPERdomain of the Env. The resulting smDAVEIs both inhibit infection with low micromolar potency and induce lysis of the HIV-1 virion. The lytic activity was selective for functional HIV-1 virions. Crucially, virolysis was found to be dependent on covalent tethering of the BNM-III-170 and Trp3 domains with various spacers, as coadministration of the un-crosslinked components proved not to be lytic. Computational modeling supports a mechanism in which DAVEIs bind to open-state Env trimers and induce relative motion of gp120 subunits that further opens the trimers. Overall, this work represents a promising new step toward the use of small-molecule DAVEIs for eradication of HIV.