Viracta Therapeutics, a clinical-stage drug development company advancing innovative approaches to treat viral-associated cancers and other serious diseases, has initiated treatment of the first patient in a Phase 1b/2 clinical trial in Epstein-Barr virus-positive (EBV⁺) lymphomas. The Company’s unique therapeutic approach is the first targeted, orally administered therapy for EBV⁺ lymphomas.

This clinical trial is the first clinical application of Viracta’s proprietary epigenetic modifying drug, tractinostat, in combination with the antiviral drug valganciclovir. The trial is planned to enroll up to 40 patients with a broad range of EBV⁺ lymphomas at sites across the US. “The presence of EBV gene sequences in patient tumor samples is the primary biomarker to select patients likely to benefit from this treatment,” stated Marshelle Smith Warren, MD, Viracta’s VP R&D and Chief Medical Officer.
“Based on previous clinical experience with viral gene activation, using an epigenetic modifying drug, we are excited to explore how the unique properties of tractinostat may benefit this high-need patient population,” stated Viracta scientific founder, Douglas Faller, MD, PhD.
Additional information regarding the VT3996-201 clinical trial can be found at ClinicalTrials.gov.
About Viracta’s Therapeutic Approach and Tractinostat
Viracta’s therapeutic approach represents a platform for a highly targeted therapy to treat a range of viral-associated cancers and other serious diseases. The treatment approach has been termed a “kick-and-kill” strategy as it combines use of an epigenetic modifier drug, tractinostat, to induce expression of certain latent viral genes (the “kick”). This enables conversion of an orally administered antiviral pro-drug, valganciclovir, to its active form to selectively eradicate dividing, cancerous cells harboring the virus (the “kill”).
Tractinostat is an orally administered class-1 histone deacetylase-selective inhibitor that is a potent inducer of targeted viral genes. In previous clinical testing, tractinostat exhibited clinical characteristics that uniquely position it for Viracta’s therapeutic approach.
About EBV Lymphomas
EBV is associated with a range of lymphoid as well as certain solid tumor malignancies. While first found in Burkitt’s lymphoma patients, EBV also plays roles in a subset of patients with Non-Hodgkin’s lymphoma, including patients with aggressive forms of Diffuse Large B Cell Lymphoma (DLBCL). EBV is also involved in about one-third of Hodgkin’s Disease patients. It is found in nearly all cases of patients with aggressive NK/T cell lymphomas. Among immuno-suppressed patients, such as solid organ or hematopoietic cell transplant patients, nearly all patients with post-transplant lymphoproliferative disorder (PTLD) have EBV-associated disease. This is also the case with most HIV- or AIDS-associated lymphoma patients. For many solid as well as liquid tumor malignancies, EBV-positivity is associated with poor prognosis with current standard of care treatment, representing a high unmet medical need.