Viracta Therapeutics Announces Notice of Allowance for U.S. Patent Application Covering the Use of its Combination Product Candidate for the Treatment of Epstein-Barr Virus-associated Lymphoma

On February 16, 2021 Viracta Therapeutics, Inc. (Viracta or the Company), a precision oncology company targeting virus-associated malignancies, reported that the U.S. Patent and Trademark Office (USPTO) has issued a Notice of Allowance for patent application No. 16/924,082 (Press release, Viracta Therapeutics, FEB 16, 2021, View Source [SID1234575154]). The allowed application, titled "Methods of Treating Virally Associated Cancers with Histone Deacetylase Inhibitors," describes the use of Viracta’s all-oral combination product candidate of nanatinostat, the Company’s proprietary investigational drug, and valganciclovir. The allowed claims cover the anticipated dose regimen to be advanced in the planned global registration trial for the treatment of Epstein-Barr virus (EBV)-associated lymphoma and other lymphoproliferative disorders. Upon its grant, the resulting patent will provide protection into at least 2040.

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

"Broadening our patent estate and extending our intellectual property protection is a strategic focus for Viracta, as we advance the development of our all-oral therapy in our global registration trial," said Ivor Royston, MD, President and Chief Executive Officer of Viracta. "We are pleased to have received this Notice of Allowance and look forward to further strengthening our patent portfolio as we expand our development in EBV-positive lymphoma and EBV-positive solid tumors."

A Notice of Allowance is issued after the USPTO makes the determination that a patent should be granted from an application. A patent from the recently allowed application is expected to be issued in the coming months. Based on its current development and commercialization plans, Viracta expects this patent to be Orange Book eligible.

Viracta’s Planned Merger with Sunesis Pharmaceuticals

On November 30, 2020, Viracta and Sunesis Pharmaceuticals, Inc. (Nasdaq: SNSS) announced the parties entered into a definitive merger agreement (the Merger Agreement) pursuant to which Viracta will combine with Sunesis in an all-stock transaction (the Merger). The merged company will focus on the advancement and expansion of Viracta’s clinical stage, precision oncology pipeline targeting virus-associated malignancies, including Viracta’s lead program for the treatment of EBV-positive relapsed/refractory lymphomas. Upon completion of the Merger, the combined company will operate under the name Viracta Therapeutics, Inc. and intends to be listed on the Nasdaq Global Market under the ticker symbol "VIRX".

Under the terms of the Merger Agreement, pending stockholder approval of the transaction, Viracta will merge with a wholly owned subsidiary of Sunesis, and stockholders of Viracta will receive shares of newly issued Sunesis common stock. Viracta stockholders are expected to own approximately 86% and Sunesis stockholders will own approximately 14% of the combined company on a fully diluted basis using the treasury stock method. The percentage of the combined company that Sunesis stockholders will own as of the close of the Merger may be subject to adjustment based on Sunesis’ net cash.

The Merger Agreement has been unanimously approved by the Board of Directors of each company. The transaction is expected to close in the first quarter of 2021, subject to approvals by stockholders of each company and other customary closing conditions.

A more complete description of the terms of and conditions of the merger can be found in Sunesis’ Form 8-K filed on November 30, 2020 with the Securities and Exchange Commission (SEC) and in the Merger Agreement, which is filed as an exhibit to that Form 8-K.

About Nanatinostat

Nanatinostat (VRx-3996) is an orally available histone deacetylase (HDAC) inhibitor being developed by Viracta. Nanatinostat is selective for specific isoforms of Class I HDACs, which is key to inducing latent viral genes which are epigenetically silenced in EBV-associated malignancies. The nanatinostat and valganciclovir combination is being investigated in EBV-positive lymphomas in an ongoing Phase 2 clinical trial [NCT03397706].

Viracta has received Fast Track designation from the FDA for the nanatinostat and valganciclovir combination in relapsed/refractory EBV positive lymphomas, as well as orphan drug designations for the treatment of post-transplant lymphoproliferative disorder, plasmablastic lymphoma, and T-cell lymphomas.