First-in-Human clinical trial of a small molecule EBNA1 inhibitor, VK-2019, in patients with Epstein-Barr positive nasopharyngeal cancer, with pharmacokinetic and pharmacodynamic studies.

Purpose: A first-in-human phase one study was conducted in nasopharyngeal carcinoma (NPC) patients to assess the safety and tolerability of VK-2019, a small molecule selective inhibitor of Epstein-Barr virus Nuclear Antigen 1 (EBNA1).

Patients And Methods: Pharmacokinetic and pharmacodynamic studies, including circulating tumor EBV DNA plasma levels, were performed. Twenty-three patients received VK-2019 orally once daily at doses ranging from 60 to 1800 mg using an accelerated titration design, with cohort expansion at 1800 mg.

Selective recruitment of host factors by HSV-1 replication centers.

Herpes simplex virus type 1 (HSV-1) enters productive infection after infecting epithelial cells, where it controls the host nucleus to make viral proteins, starts viral DNA synthesis and assembles infectious virions. In this process, replicating viral genomes are organized into replication centers to facilitate viral growth. HSV-1 is known to use host factors, including host chromatin and host transcription regulators, to transcribe its genes; however, the invading virus also encounters host defense and stress responses to inhibit viral growth.