Discovery of small-molecule PD-1/PD-L1 antagonists through combined virtual screening and experimental validation.

Inhibition of the interaction between the PD-1 protein on activated lymphocytes and the PD-L1 protein on tumors represents a novel therapeutic approach for selective activation of the innate immune response against a variety of cancers. Therefore, the present study utilized a combined virtual and experimental screening approach to screen databases of both lead-like and larger molecules for identification of novel inhibitors of PD-1/PD-L1 interaction. First, high-throughput virtual screening of ∼3.

Machine-Learning Guided Discovery of Bioactive Inhibitors of PD1-PDL1 Interaction.

The selective activation of the innate immune system through blockade of immune checkpoint PD1-PDL1 interaction has proven effective against a variety of cancers. In contrast to six antibody therapies approved and several under clinical investigation, the development of small-molecule PD1-PDL1 inhibitors is still in its infancy with no such drugs approved yet. Nevertheless, a promising series of small molecules inducing PDL1 dimerization has revealed important spatio-chemical features required for effective PD1-PDL1 inhibition through PDL1 sequestration.

Identification of the FDA-Approved Drug Pyrvinium as a Small-Molecule Inhibitor of the PD-1/PD-L1 Interaction.

Immune checkpoint blockade involving inhibition of the PD-1/PD-L1 interaction has provided unprecedented clinical benefits in treating a variety of tumors. To date, a total of six antibodies that bind to either PD-1 or PD-L1 protein and in turn inhibit the PD-1/PD-L1 interaction have received clinical approvals. Despite being highly effective, these expensive large biotherapeutics possess several inherent pharmacokinetic limitations that can be successfully overcome through the use of low-molecular-weight inhibitors.