Viracta Therapeutics Stock Price, News & Analysis

Viracta Therapeutics, Inc. (Nasdaq: VIRX) has operated as a clinical-stage precision oncology company focused on the treatment and prevention of virus-associated cancers. According to company disclosures, Viracta concentrated on cancers associated with the Epstein-Barr virus (EBV), a virus estimated to be linked to a portion of the global cancer burden. The company’s work is situated within the pharmaceutical preparation manufacturing industry and the broader biopharmaceutical and oncology research space.

Viracta’s lead product candidate has been Nana-val, an all-oral combination therapy that pairs its proprietary investigational drug nanatinostat, a histone deacetylase (HDAC) inhibitor, with the antiviral agent valganciclovir. Nanatinostat is described as selective for specific isoforms of Class I HDACs, which are key to inducing viral genes that are epigenetically silenced in EBV-associated malignancies. By combining nanatinostat with valganciclovir, Viracta has pursued what it refers to as a “Kick and Kill” approach in EBV-associated cancers.

Company materials state that Nana-val has been evaluated in multiple clinical trials. These have included a global, multicenter, open-label Phase 2 basket trial known as NAVAL-1 in relapsed or refractory (R/R) EBV-positive lymphomas, and a multinational Phase 1b/2 trial in recurrent or metastatic EBV-positive nasopharyngeal carcinoma and other advanced EBV-positive solid tumors. In these studies, Viracta has reported that Nana-val demonstrated antitumor activity and a generally well-tolerated safety profile in certain EBV-positive lymphoma populations, including peripheral T-cell lymphoma (PTCL), based on company communications.

Viracta has described EBV-positive PTCL and other EBV-associated lymphomas as areas of high unmet medical need. Company communications reference literature indicating that a significant subset of peripheral T-cell lymphomas are associated with EBV and that outcomes for EBV-positive disease can be inferior to EBV-negative disease. Against this backdrop, Viracta’s clinical development plans for Nana-val have focused on EBV-positive lymphoma subtypes, including second-line treatment settings in relapsed or refractory EBV-positive PTCL.

In addition to lymphoma-focused work, Viracta has reported conducting a Phase 1b/2 study (Study 301) of Nana-val in patients with recurrent or metastatic EBV-positive nasopharyngeal carcinoma and other advanced EBV-positive solid tumors. The trial design described by the company includes dose-escalation to determine a recommended Phase 2 dose, followed by dose-optimization and randomized cohorts to further evaluate antitumor activity, safety, pharmacokinetics, and potential pharmacodynamic biomarkers.

Viracta has repeatedly characterized itself as a precision oncology company, emphasizing virus-associated cancers as its core focus. The company has also indicated that it is pursuing application of its “Kick and Kill” approach in other EBV-related or virus-associated diseases and cancers, beyond the lead indications studied in NAVAL-1 and Study 301.

Corporate status and listing

Viracta Therapeutics, Inc. has been listed on the Nasdaq Stock Market under the ticker symbol VIRX. A Form 25 filed with the U.S. Securities and Exchange Commission identifies Viracta Therapeutics, Inc. as the issuer and the Nasdaq Stock Market LLC as the exchange, and relates to the removal of the company’s common stock from listing and/or registration under Section 12(b) of the Securities Exchange Act of 1934. The Form 25 filing is a formal notification that the class of common stock is being removed from listing on Nasdaq.

Separately, a company news release dated February 5, 2025 states that Viracta Therapeutics announced the termination of its employees and plans to wind down operations. The same announcement notes that the company is exploring potential strategic alternatives for its development programs. The board of directors appointed a single officer and sole board member to implement the wind down, described as an individual with experience in distressed businesses and corporate wind-down phases.

Prior to the wind-down announcement, Viracta had reported measures to conserve resources and extend its cash runway, including reductions in force and a resizing of its board of directors. These steps were described in connection with a reprioritization of resources to focus on the Nana-val development program in relapsed or refractory EBV-positive peripheral T-cell lymphoma.

Clinical development focus

Across multiple news releases, Viracta has highlighted several aspects of Nana-val’s clinical development:

• Evaluation of Nana-val in a pivotal or potentially registrational Phase 2 basket trial (NAVAL-1) in relapsed or refractory EBV-positive lymphomas, using a Simon two-stage design with expansion in lymphoma subtypes showing promising activity.
• Reporting of positive combined Stage 1 and Stage 2 data in the EBV-positive PTCL cohort of NAVAL-1, with company statements describing substantial antitumor activity and a generally well-tolerated safety profile.
• Productive interactions with the U.S. Food and Drug Administration (FDA) regarding a potential regulatory path for Nana-val in relapsed or refractory EBV-positive PTCL, and plans—described in company communications—to focus analyses on the second-line EBV-positive PTCL subpopulation in the NAVAL-1 expansion phase.
• Plans outlined by the company to initiate a randomized controlled trial in second-line EBV-positive PTCL patients to support potential registration, subject to financing and other conditions, prior to the later decision to wind down operations.
• Progress in a Phase 1b/2 study of Nana-val in EBV-positive nasopharyngeal carcinoma and other advanced EBV-positive solid tumors, including determination of a recommended Phase 2 dose in advanced EBV-positive solid tumors as reported by the company.

Viracta’s disclosures also describe broader scientific context around EBV-associated cancers, noting that EBV infection is widespread in the adult population and that latent EBV can contribute to malignant transformation, particularly in immunocompromised patients. The company has cited estimates that EBV is associated with a portion of the global cancer burden, including lymphoma, nasopharyngeal carcinoma, and gastric cancer.

Wind down and strategic alternatives

In late 2024, Viracta announced the closure of its pivotal Phase 2 NAVAL-1 trial in relapsed or refractory EBV-positive lymphomas as part of a process to explore a broad range of strategic alternatives. The company stated that the decision to voluntarily close the trial was not the result of any new safety finding. Potential alternatives described by the company included a merger, licensing agreement, sale, or other strategic transaction, with the goal of maximizing value.

On February 5, 2025, Viracta publicly stated that it had terminated its employees and would wind down operations, while continuing to explore potential strategic alternatives for its development programs. This marks a significant change from its prior role as an active clinical-stage precision oncology company. A subsequent Form 25 filing by Nasdaq on July 10, 2025 provides formal notice of the removal of Viracta’s common stock from listing and/or registration on the Nasdaq Stock Market.

Investors and researchers reviewing Viracta Therapeutics (VIRX) should consider both the historical clinical development activities around Nana-val and the later announcements regarding closure of trials, workforce reductions, wind down of operations, and delisting from Nasdaq, as documented in company news releases and SEC filings.