EBV-Related Post-Transplant Lymphoproliferative Disorder

- Reported combined Stage 1 and Stage 2 results from the relapsed or refractory EBV-positive peripheral T-cell lymphoma (PTCL) cohort of the Phase 2 NAVAL-1 trial demonstrating Nana-val’s substantial antitumor activity and generally well-tolerated safety profile - - New positive data and productive feedback from the FDA support updated Nana-val clinical development plan in EBV-positive PTCL patients; randomized controlled trial planned to begin in the second half of 2025 to support potential registration - - Appointed Michael Faerm as Chief Financial Officer - SAN DIEGO, Aug. 14, 2024 (GLOBE NEWSWIRE) -- Viracta Therapeutics, Inc. (Nasdaq: VIRX), a clinical-stage precision oncology company focused on the treatment and prevention of virus-associated cancers that impact patients worldwide, today reported financial results for the second quarter of 2024 and provided a business update. “In the second quarter, we took several important steps to drive forward our clinical development program for Nana-val, our first-in-class, all-oral combination treatment regimen for Epstein-Barr virus (EBV) associated cancers,” said Mark Rothera, President and Chief Executive Officer of Viracta. “We received productive feedback from our meeting with the FDA and are encouraged by additional positive data from the ongoing NAVAL-1 trial, particularly in the second-line EBV-positive PTCL subgroup. To optimize the clinical benefit of Nana-val, we plan to focus on the second-line EBV-positive PTCL subpopulation in the NAVAL-1 trial’s expansion phase and initiate a randomized controlled trial in 2025 to potentially support registration. We believe our sharpened focus on the EBV-positive lymphoma program will propel us forward to key milestones and support our speed to market strategy. We look forward to providing more updates on our progress.” Clinical Trial Updates and Anticipated Milestones Phase 2 NAVAL-1 trial of Nana-val (nanatinostat in combination with valganciclovir) in patients with relapsed or refractory (R/R) Epstein-Barr virus-positive (EBV+) lymphoma Clinical Trial Updates: Announced positive combined Stage 1 and Stage 2 data (n=21) in the R/R EBV+ PTCL cohort of patients treated with nanatinostat (20 mg orally once daily, 4 days/week) in combination with valganciclovir (900 mg orally once daily, 7 days/week) across the first two stages of the study. As of the June 28, 2024 data cutoff, combined Stages 1 and 2 data demonstrated Nana-val’s substantial antitumor activity and generally well-tolerated safety profile with a median duration of response (DOR) that has not yet been reached. In the R/R EBV+ PTCL population, the overall response rate (ORR) was 33% and the complete response rate (CRR) was 19% in the intent-to-treat (ITT) population (N=21); the ORR was 41% and the CRR was 24% in the efficacy-evaluable (EE) population (N=17).Notably, there was a particularly robust clinical response observed in the second-line EBV+ PTCL subpopulation, as the ORR was 60% and the CRR was 30% in the intent-to-treat population (n=10), and the ORR was 67% and the CRR was 33% in the efficacy-evaluable population (n=9). Held a productive FDA meeting to align on a potential regulatory path forward for Nana-val in patients with R/R EBV+ PTCL. Based on feedback from the FDA and the particularly robust response rates observed in the second-line treatment setting, Viracta will focus the primary analysis on the second-line EBV+ PTCL subpopulation in the ongoing NAVAL-1 trial’s expansion phase. The Company plans to begin a randomized controlled trial (RCT) of Nana-val in the second-line treatment of EBV+ PTCL patients in 2025. Viracta believes this strategy will best position Nana-val for a potential NDA filing in 2026 for accelerated approval based on an interim analysis of second-line EBV+ PTCL patient data from the NAVAL-1 trial, provided that the ORR and DOR are compelling and the RCT is well underway; for accelerated approval based on final analysis of NAVAL-1 trial data; or for accelerated or full approval based on the outcomes of the RCT at interim or final analysis, respectively. Anticipated MilestonesViracta plans to deliver on the following milestones: The recommended Phase 2 dose in patients with advanced EBV+ solid tumors is expected to be determined in the second half of 2024.Report additional data from the expansion phase of the NAVAL-1 trial in second-line EBV+ PTCL patients in the fourth quarter of 2024.Report Stage 1 data from patients with R/R EBV+ diffuse large B-cell lymphoma (DLBCL) in the first half of 2025.Meet with the FDA to finalize the proposed RCT design in the second-line treatment of patients with EBV+ PTCL in the first half of 2025. Initiate the RCT in the second half of 2025. Present interim analysis outcomes from the NAVAL-1 trial in second-line EBV+ PTCL patients in 2026.File NDA for accelerated approval in 2026 based on interim analysis of the NAVAL-1 trial’s expansion cohort. Business Updates Appointed Michael Faerm as Chief Financial Officer. Mr. Faerm is a seasoned biotech executive with more than 25 years of experience in life sciences companies, equity research and investment banking.Viracta has aligned resources to prioritize its more advanced EBV+ lymphoma and will pause its EBV+ solid tumor program. Along with this pipeline reprioritization, a reduction in force has been implemented that impacts approximately 23% of the company’s employees. Second Quarter 2024 Financial Results Cash position – Cash, cash equivalents, and short-term investments totaled approximately $30.0 million as of June 30, 2024, which Viracta expects will be sufficient to fund operations late into the first quarter of 2025.Research and development expenses – Research and development expenses were approximately $6.5 million and $16.5 million for the three and six months ended June 30, 2024, respectively, compared to approximately $8.2 million and $15.8 million for the same periods in 2023. The decrease in research and development expenses for the three months ended June 30, 2024 compared to the same period in 2023, was driven by decreases in costs incurred to support the advancement and expansion of our clinical development programs, including incremental costs to support NAVAL-1, our Phase 2 trial of Nana-val in patients with R/R EBV+ lymphomas and personnel-related costs. The increase in research and development expenses for the six months ended June 30, 2024 compared to the same period in 2023, was largely due to a non-cash adjustment for insurance costs related to the February 2021 reverse merger with Sunesis Pharmaceuticals of $1.8 million, partially offset by decrease in costs incurred related to our clinical development programs and personnel-related costs.General and administrative expenses – General and administrative expenses were approximately $3.0 million and $7.0 million for the three and six months ended June 30, 2024, respectively, compared to $4.3 million and $8.9 million for the same periods in 2023. The decrease in general and administrative expenses was largely due to decreases in personnel-related costs, corporate liability insurance premiums and legal costs.Net loss – Net loss was approximately $9.8 million, or $0.25 per share (basic and diluted), for the quarter ended June 30, 2024, compared to a net loss of $12.5 million, or $0.32 per share (basic and diluted), for the same period in 2023. This change was primarily the result of decreases in research and development expenses and personnel-related costs. Net loss was approximately $19.0 million, or $0.48 per share, (basic and diluted) for the six months ended June 30, 2024, compared to a net loss of $24.7 million, or $0.64 per share, (basic and diluted) for the same period in 2023. This change was primarily the result of $5.0 million of other income received related to the monetization of a pre-commercialization, event-based milestone from Day One Biopharmaceuticals, Inc. in March 2024, partially offset by the non-cash adjustment for insurance costs related to the February 2021 merger of $1.8 million. About the NAVAL-1 TrialNAVAL-1 (NCT05011058) is a global, multicenter, clinical trial of Nana-val in patients with relapsed or refractory (R/R) Epstein-Barr virus-positive (EBV+) lymphoma. This trial employs a Simon two-stage design where, in Stage 1, participants are enrolled into one of three indication cohorts based on EBV+ lymphoma subtype. If two objective responses are achieved within a lymphoma subtype in Stage 1 (n=10), then additional patients will be enrolled in Stage 2 for a total of 21 patients. EBV+ lymphoma subtypes demonstrating promising antitumor activity in Stage 2 may be further expanded following discussion with regulators to potentially support registration. About Nana-val (Nanatinostat and Valganciclovir)Nanatinostat is an orally available histone deacetylase (HDAC) inhibitor being developed by Viracta. Nanatinostat is selective for specific isoforms of Class I HDACs, which are key to inducing viral genes that are epigenetically silenced in Epstein-Barr virus (EBV)-associated malignancies. Nanatinostat is currently being investigated in combination with the antiviral agent valganciclovir as an all-oral combination therapy, Nana-val, in various subtypes of EBV-associated malignancies. Ongoing trials include a potentially registrational, global, multicenter, open-label Phase 2 basket trial in multiple subtypes of relapsed or refractory (R/R) EBV+ lymphoma (NAVAL-1) as well as a multinational Phase 1b/2 clinical trial in patients with recurrent or metastatic (R/M) EBV+ NPC and other advanced EBV+ solid tumors. About Peripheral T-Cell LymphomaT-cell lymphomas comprise a heterogeneous group of rare and aggressive malignancies, including peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) and angioimmunoblastic T-cell lymphoma (AITL). There are approximately 5,600 newly diagnosed T-cell lymphoma patients and approximately 2,600 newly diagnosed PTCL-NOS and AITL patients in the U.S. annually. Approximately 70% of these patients are either refractory to first-line therapy, or eventually experience relapse of their disease. Clinical trials are currently recommended for all lines of PTCL therapy, and most patients with R/R PTCL have poor outcomes, with median progression-free survival and median overall survival times reported to be 3.7 and 6.5 months, respectively. Approximately 40% to 65% of PTCL is associated with EBV, the incidence of EBV+ PTCL varies by geography, and reported outcomes for patients with EBV+ PTCL are inferior to those whose disease is EBV-negative. There is no approved targeted treatment specific for EBV+ PTCL, and therefore this represents a high unmet medical need. About EBV-Associated CancersApproximately 90% of the world's adult population is infected with EBV. Infections are commonly asymptomatic or associated with mononucleosis. Following infection, the virus remains latent in a small subset of cells for the duration of the patient's life. Cells containing latent virus are increasingly susceptible to malignant transformation. Patients who are immunocompromised are at an increased risk of developing EBV-positive (EBV+) lymphomas. EBV is estimated to be associated with approximately 2% of the global cancer burden including lymphoma, nasopharyngeal carcinoma (NPC), and gastric cancer. About Viracta Therapeutics, Inc.Viracta is a clinical-stage precision oncology company focused on the treatment and prevention of virus-associated cancers that impact patients worldwide. Viracta’s lead product candidate is an all-oral combination therapy of its proprietary investigational drug, nanatinostat, and the antiviral agent valganciclovir (collectively referred to as Nana-val). Nana-val is currently being evaluated in multiple ongoing clinical trials, including a potentially registrational, global, multicenter, open-label Phase 2 basket trial for the treatment of multiple subtypes of relapsed or refractory (R/R) Epstein-Barr virus-positive (EBV+) lymphoma (NAVAL-1), as well as a multinational, open-label Phase 1b/2 clinical trial for the treatment of patients with recurrent or metastatic (R/M) EBV+ nasopharyngeal carcinoma (NPC) and other advanced EBV+ solid tumors. Viracta is also pursuing the application of its “Kick and Kill” approach in other virus-related cancers. For additional information, please visit www.viracta.com. Forward-Looking StatementsThis communication contains "forward-looking" statements within the meaning of the Private Securities Litigation Reform Act of 1995, including, without limitation, statements regarding: the details, timeline and expected progress for Viracta's ongoing and anticipated clinical trials and updates regarding the same, Viracta’s clinical focus and strategy, the Company’s expectations related to the FDA submission process and timelines, expectations regarding the Company’s target patient populations, and expectations regarding the Company’s cash runway. Risks and uncertainties related to Viracta that may cause actual results to differ materially from those expressed or implied in any forward-looking statement include, but are not limited to: Viracta's ability to successfully enroll patients in and complete its ongoing and planned clinical trials; Viracta's plans to develop and commercialize its product candidates, including all oral combinations of nanatinostat and valganciclovir; the timing of initiation of Viracta's planned clinical trials; the timing of the availability of data from Viracta's clinical trials; previous preclinical and clinical results may not be predictive of future clinical results; the timing of any planned investigational new drug application or new drug application; Viracta's plans to research, develop, and commercialize its current and future product candidates; the clinical utility, potential benefits, and market acceptance of Viracta's product candidates; Viracta's ability to manufacture or supply nanatinostat, valganciclovir, and pembrolizumab for clinical testing; and Viracta's estimates regarding its ability to fund ongoing operations into 2025, future expenses, capital requirements, and need for additional financing in the future. If any of these risks materialize or underlying assumptions prove incorrect, actual results could differ materially from the results implied by these forward-looking statements. Additional risks and uncertainties that could cause actual outcomes and results to differ materially from those contemplated by the forward-looking statements are included under the caption "Risk Factors" and elsewhere in Viracta's reports and other documents that Viracta has filed, or will file, with the SEC from time to time and available at www.sec.gov. The forward-looking statements included in this communication are made only as of the date hereof. Viracta assumes no obligation and does not intend to update these forward-looking statements, except as required by law or applicable regulation. Investor Relations Contact:Michael FaermChief Financial OfficerViracta Therapeutics, Inc.ir@viracta.com SOURCE Viracta Therapeutics, Inc. -- Financial tables attached – Viracta Therapeutics, Inc.Selected Balance Sheet Highlights(in thousands) June 30, December 31, 2024 2023 (Unaudited) Cash, cash equivalents and short-term investments$30,005 $53,691 Total assets$31,322 $56,692 Total liabilities$28,651 $38,373 Stockholders' equity$2,671 $18,319 Viracta Therapeutics, Inc.Condensed Consolidated Statement of Operations and Comprehensive Loss(in thousands except share and per share data)(Unaudited) Three Months Ended June 30, Six Months Ended June 30, 2024 2023 2024 2023 Operating expenses: Research and development$6,548 $8,197 $16,504 $15,804 General and administrative 3,041 4,253 6,961 8,853 Total operating expenses 9,589 12,450 23,465 24,657 Loss from operations (9,589) (12,450) (23,465) (24,657)Total other income (expense) (241) (34) 4,494 (36)Net loss (9,830) (12,484) (18,971) (24,693)Unrealized gain (loss) on short-term investments 1 (28) (14) 63 Comprehensive loss (9,829) (12,512) (18,985) (24,630)Net loss per share, basic and diluted$(0.25) $(0.32) $(0.48) $(0.64)Weighted-average common shares outstanding, basic and diluted 39,404,975 38,560,376 39,364,469 38,509,887

- New combined Stage 1 and Stage 2 results from the relapsed or refractory EBV-positive peripheral T-cell lymphoma (PTCL) cohort of the Phase 2 NAVAL-1 trial further demonstrate Nana-val’s substantial antitumor activity and generally well-tolerated safety profile - - Productive FDA meeting held to align on a potential regulatory path forward for Nana-val in patients with relapsed or refractory EBV-positive PTCL - - Updated Nana-val clinical development plan implemented to optimize its clinical benefit in EBV-positive PTCL patients and expedite a randomized controlled trial to support potential registration - - Viracta to host conference call and webcast on Wednesday, August 14 at 8:30 a.m. ET, featuring Pierluigi Porcu, M.D., Professor of Medical Oncology, Director of the Division of Hematologic Malignancies and Hematopoietic Stem Cell Transplantation at Thomas Jefferson University - SAN DIEGO, Aug. 14, 2024 (GLOBE NEWSWIRE) -- Viracta Therapeutics, Inc. (Nasdaq: VIRX), a clinical-stage precision oncology company focused on the treatment and prevention of virus-associated cancers that impact patients worldwide, today reported positive Phase 2 NAVAL-1 trial results from Stages 1 and 2 of the relapsed or refractory (R/R) Epstein-Barr virus-positive (EBV+) peripheral T-cell lymphoma (PTCL) cohort. Additionally, the Company received productive feedback from its meeting with the U.S. Food and Drug Administration (FDA), providing clarity on the potential regulatory path to initial registration of Nana-val in patients with R/R EBV+ PTCL. Based on FDA’s feedback, Viracta plans to begin a randomized controlled trial (RCT) of Nana-val in the second half of 2025. “We are pleased to present important additional data from our NAVAL-1 trial, which further supports Nana-val’s potential to address the high unmet medical needs of patients living with relapsed or refractory EBV-positive PTCL,” said Darrel P. Cohen, M.D., Ph.D., Chief Medical Officer of Viracta. “Nana-val demonstrated substantial antitumor activity with a generally well-tolerated safety profile across Stage 1 and Stage 2 of the relapsed or refractory EBV-positive PTCL cohort, with a median duration of response that has not yet been reached. We are also encouraged by the particularly robust clinical responses observed in the second-line EBV-positive PTCL subgroup.” Mark Rothera, President and Chief Executive Officer of Viracta, added, “Aligning with the FDA on the potential path forward in relapsed or refractory EBV-positive PTCL marks a critical step towards bringing Nana-val to patients. EBV-positive PTCL is an aggressive cancer with survival rates that decline precipitously 12-24 months after diagnosis. Published literature suggests that EBV-positive lymphomas are a distinct oncological disease associated with poorer survival outcomes than EBV-negative lymphomas. We believe it is critical to treat these patients as early as possible with an EBV-targeted therapy to improve patient outcomes. Our updated Nana-val clinical development plan is designed to address this urgent need and expedite a randomized controlled trial, which we plan to initiate in 2025 to support potential registration.” Key Takeaways from the R/R EBV+ PTCL Cohort of the Phase 2 NAVAL-1 TrialOverview: A total of 21 patients with primarily Stage III-IV disease (who had received ≥1 [median 2] prior systemic PTCL therapies) received nanatinostat (20 mg orally once daily, 4 days/week) in combination with valganciclovir (900 mg orally once daily, 7 days/week) across the first two stages of the study. Data generated from the expansion phase of the R/R EBV+ PTCL cohort may be shared in future updates. As of the June 28, 2024 data cutoff, combined Stages 1 and 2 data demonstrated: In the R/R EBV+ PTCL population: The overall response rate (ORR) was 33% and the complete response rate (CRR) was 19% in the intent-to-treat (ITT) population (n=21); the ORR was 41% and the CRR was 24% in the efficacy-evaluable (EE) population (n=17). In the second-line EBV+ PTCL subpopulation: The ORR was 60% and the CRR was 30% in the ITT population (n=10); the ORR was 67% and the CRR was 33% in the EE population (n=9). Median duration of response (DOR) has not yet been reached. Two responding patients proceeded to hematopoietic stem-cell transplant without relapse, one of whom remains in response over 16 months. Nana-val was generally well-tolerated: The most common treatment-related adverse events were fatigue, nausea, decreased appetite, diarrhea, platelet count decreased, and anemia. These adverse events were primarily mild to moderate in severity and generally manageable or reversible. Nana-val Clinical Development Plan: Next StepsBased on the Company’s meeting with FDA and the particularly robust response rates observed in the second-line treatment setting, Viracta will focus Nana-val’s clinical development on patients with R/R EBV+ PTCL as follows: First, the Company will focus the primary analysis on the second-line EBV+ PTCL subpopulation in the ongoing NAVAL-1 trial’s expansion phase. Second, the Company plans to begin an RCT of Nana-val in the second-line treatment of EBV+ PTCL patients in 2025. Viracta believes this strategy will best position Nana-val for a potential NDA filing in 2026 for accelerated approval based on an interim analysis of second-line EBV+ PTCL patient data from the NAVAL-1 trial, provided that the ORR and DOR are compelling and the RCT is well underway. In addition, it creates the opportunity for accelerated approval based on final analysis of NAVAL-1 trial data, or for accelerated or full approval based on the outcomes of the RCT at interim or final analysis, respectively. Corporate Update Viracta has aligned resources to prioritize its EBV+ lymphoma program and plans to deliver on key potential Nana-val development milestones as follows: Pause the EBV+ solid tumor program to focus resources on the more advanced EBV+ lymphoma program. The recommended Phase 2 dose in patients with advanced EBV+ solid tumors is expected to be determined in the second half of 2024. Report additional data from the ongoing expansion phase of the NAVAL-1 trial in second-line EBV+ PTCL patients in the fourth quarter of 2024.Report Stage 1 data from patients with R/R EBV+ diffuse large B-cell lymphoma (DLBCL) in the first half of 2025.Meet with the FDA to finalize the proposed RCT design in the second-line treatment of patients with EBV+ PTCL in the first half of 2025. Initiate the RCT in the second half of 2025. Present interim analysis outcomes from the expansion phase of the NAVAL-1 trial in second-line EBV+ PTCL patients in 2026.File NDA for accelerated approval in 2026 based on interim analysis of the NAVAL-1 trial’s expansion cohort. Along with this pipeline reprioritization, a reduction in force has been implemented that impacts approximately 23% of the Company’s employees. Conference CallViracta will host an investor call on Wednesday, August 14 at 8:30 a.m. ET to discuss the positive Phase 2 NAVAL-1 trial results from Stages 1 and 2 of the R/R EBV+ PTCL cohort. A live question and answer session will follow the formal presentation. To register, click here. About the NAVAL-1 TrialNAVAL-1 (NCT05011058) is a global, multicenter, clinical trial of Nana-val in patients with relapsed or refractory (R/R) Epstein-Barr virus-positive (EBV+) lymphoma. This trial employs a Simon two-stage design where, in Stage 1, participants are enrolled into one of three indication cohorts based on EBV+ lymphoma subtype. If two objective responses are achieved within a lymphoma subtype in Stage 1 (n=10), then additional patients will be enrolled in Stage 2 for a total of 21 patients. EBV+ lymphoma subtypes demonstrating promising antitumor activity in Stage 2 may be further expanded following discussion with regulators to potentially support registration. About Nana-val (Nanatinostat and Valganciclovir)Nanatinostat is an orally available histone deacetylase (HDAC) inhibitor being developed by Viracta. Nanatinostat is selective for specific isoforms of Class I HDACs, which are key to inducing viral genes that are epigenetically silenced in Epstein-Barr virus (EBV)-associated malignancies. Nanatinostat is currently being investigated in combination with the antiviral agent valganciclovir as an all-oral combination therapy, Nana-val, in various subtypes of EBV-associated malignancies. Ongoing trials include a potentially registrational, global, multicenter, open-label Phase 2 basket trial in multiple subtypes of relapsed or refractory (R/R) EBV+ lymphoma (NAVAL-1) as well as a multinational Phase 1b/2 clinical trial in patients with recurrent or metastatic (R/M) EBV+ NPC and other advanced EBV+ solid tumors. About Peripheral T-Cell LymphomaT-cell lymphomas comprise a heterogeneous group of rare and aggressive malignancies, including peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) and angioimmunoblastic T-cell lymphoma (AITL). There are approximately 5,600 newly diagnosed T-cell lymphoma patients and approximately 2,600 newly diagnosed PTCL-NOS and AITL patients in the U.S. annually. Approximately 70% of these patients are either refractory to first-line therapy, or eventually experience relapse of their disease. Clinical trials are currently recommended for all lines of PTCL therapy, and most patients with R/R PTCL have poor outcomes, with median progression-free survival and median overall survival times reported to be 3.7 and 6.5 months, respectively. Approximately 40% to 65% of PTCL is associated with EBV, the incidence of EBV+ PTCL varies by geography, and reported outcomes for patients with EBV+ PTCL are inferior to those whose disease is EBV-negative. There is no approved targeted treatment specific for EBV+ PTCL, and therefore this represents a high unmet medical need. About EBV-Associated CancersApproximately 90% of the world's adult population is infected with EBV. Infections are commonly asymptomatic or associated with mononucleosis. Following infection, the virus remains latent in a small subset of cells for the duration of the patient's life. Cells containing latent virus are increasingly susceptible to malignant transformation. Patients who are immunocompromised are at an increased risk of developing EBV-positive (EBV+) lymphomas. EBV is estimated to be associated with approximately 2% of the global cancer burden including lymphoma, nasopharyngeal carcinoma (NPC), and gastric cancer. About Viracta Therapeutics, Inc.Viracta is a clinical-stage precision oncology company focused on the treatment and prevention of virus-associated cancers that impact patients worldwide. Viracta’s lead product candidate is an all-oral combination therapy of its proprietary investigational drug, nanatinostat, and the antiviral agent valganciclovir (collectively referred to as Nana-val). Nana-val is currently being evaluated in multiple ongoing clinical trials, including a potentially registrational, global, multicenter, open-label Phase 2 basket trial for the treatment of multiple subtypes of relapsed or refractory (R/R) Epstein-Barr virus-positive (EBV+) lymphoma (NAVAL-1), as well as a multinational, open-label Phase 1b/2 clinical trial for the treatment of patients with recurrent or metastatic (R/M) EBV+ nasopharyngeal carcinoma (NPC) and other advanced EBV+ solid tumors. Viracta is also pursuing the application of its “Kick and Kill” approach in other virus-related cancers. For additional information, please visit www.viracta.com. Forward-Looking StatementsThis communication contains "forward-looking" statements within the meaning of the Private Securities Litigation Reform Act of 1995, including, without limitation, statements regarding: the details, timeline and expected progress for Viracta's ongoing and anticipated clinical trials and updates regarding the same, Viracta’s clinical focus and strategy, the Company’s expectations related to the FDA submission process and timelines, expectations regarding the Company’s target patient populations, and expectations regarding the Company’s cash runway. Risks and uncertainties related to Viracta that may cause actual results to differ materially from those expressed or implied in any forward-looking statement include, but are not limited to: Viracta's ability to successfully enroll patients in and complete its ongoing and planned clinical trials; Viracta's plans to develop and commercialize its product candidates, including all oral combinations of nanatinostat and valganciclovir; the timing of initiation of Viracta's planned clinical trials; the timing of the availability of data from Viracta's clinical trials; previous preclinical and clinical results may not be predictive of future clinical results; the timing of any planned investigational new drug application or new drug application; Viracta's plans to research, develop, and commercialize its current and future product candidates and the clinical utility, potential benefits, and market acceptance of Viracta's product candidates; Viracta's ability to manufacture or supply nanatinostat and valganciclovir for clinical testing. If any of these risks materialize or underlying assumptions prove incorrect, actual results could differ materially from the results implied by these forward-looking statements. Additional risks and uncertainties that could cause actual outcomes and results to differ materially from those contemplated by the forward-looking statements are included under the caption "Risk Factors" and elsewhere in Viracta's reports and other documents that Viracta has filed, or will file, with the SEC from time to time and available at www.sec.gov. The forward-looking statements included in this communication are made only as of the date hereof. Viracta assumes no obligation and does not intend to update these forward-looking statements, except as required by law or applicable regulation. Investor Relations Contact:Michael FaermChief Financial OfficerViracta Therapeutics, Inc.ir@viracta.com SOURCE Viracta Therapeutics, Inc.

THOUSAND OAKS, Calif.--( BUSINESS WIRE )-- Atara Biotherapeutics, Inc. (Nasdaq: ATRA), a leader in T-cell immunotherapy, leveraging its novel allogeneic Epstein-Barr virus (EBV) T-cell platform to develop transformative therapies for patients with cancer and autoimmune diseases, today reported financial results for the second quarter 2024, recent business highlights, and key upcoming milestones for 2024. “ Building on the recent BLA acceptance with Priority Review for tab-cel, we are making significant progress with the agency towards the target action date of January 15, 2025, while supporting our partner Pierre Fabre with their U.S. launch preparation,” said Pascal Touchon, President and Chief Executive Officer of Atara. “ During the quarter we continued to advance the clinical development of our lead CAR T program, ATA3219, and remain on track to deliver key value creating milestones within the next 12 months. This is highlighted by initial data from our non-Hodgkin’s lymphoma study anticipated in the first quarter of 2025, which we believe will provide a read-through for ATA3219’s potential in autoimmune disease. On that front, we plan to initiate our ATA3219 Systemic Lupus Erythematosus trial in the fourth quarter, including the cohort without lymphodepletion, with initial data expected in mid-2025.” Dr. Touchon continued, “ Following the landmark milestone of the world’s first-ever approval of an allogeneic T-cell therapy and with the potential first U.S. approval approaching, we are advancing our differentiated allogeneic CAR-T programs into the clinic. With the Company in a strong position, I have decided to move into the role of Chairman for personal reasons to dedicate more time to my family. I look forward to having a very active and strategic advisory role as board chair and continuing to help Atara create value with the potential tab-cel U.S. approval and initial clinical data with ATA3219. I believe the future of Atara is bright under the leadership of Cokey Nguyen, Ph.D. who will be promoted to the role of President and CEO. Cokey is a visionary leader in the cell therapy field, and our Board of Directors values his deep commitment to our staff and to patients as well as his expertise across the breadth of our business.” “ I admire the strong foundation we built under Pascal’s leadership. I am honored to serve as Atara’s CEO at this pivotal time to continue our journey to get tab-cel approved in the U.S. and to unlock the disruptive potential of our allogeneic CAR-T platform,” said Cokey Nguyen, Ph.D. “ I look forward to working alongside our world-class and innovative teams to rapidly innovate and strive to develop better cell therapy treatment options for patients.” Tabelecleucel (tab-cel ® or Ebvallo ™ ) for Post-Transplant Lymphoproliferative Disease (PTLD) U.S. Food and Drug Administration (FDA) accepted the filing of Atara’s Biologics License Application (BLA) for tabelecleucel (tab-cel ® ) indicated as monotherapy for treatment of adult and pediatric patients two years of age and older with Epstein-Barr virus positive post-transplant lymphoproliferative disease (EBV+ PTLD) who have received at least one prior therapy. For solid organ transplant patients, prior therapy includes chemotherapy unless chemotherapy is inappropriate The BLA has been granted Priority Review with a Prescription Drug User Fee Act (PDUFA) target action date of January 15, 2025 The data package for the filing includes pivotal and supportive data covering more than 430 patients treated with tab-cel across multiple life-threatening diseases The BLA submission is supported by the latest pivotal ALLELE study data-cut that demonstrated a statistically significant 48.8% Objective Response Rate (ORR) (p<0.0001) and favorable safety profile consistent with previous analyses Atara received a $20 million milestone payment from Pierre Fabre Laboratories in August 2024, following the acceptance of the tab-cel BLA, with the potential to receive a $60 million milestone payment from Pierre Fabre contingent upon FDA approval of the tab-cel BLA ATA3219: CD19 Program in Lupus Nephritis (LN) Atara expects to initiate a Phase 1 study of ATA3219 as a monotherapy for the treatment of systemic lupus erythematosus (SLE) with kidney involvement (lupus nephritis [LN]) in Q4 2024 with initial clinical data anticipated in mid-2025 The Phase 1 open-label, dose-escalation study is designed to evaluate safety, preliminary efficacy, pharmacokinetics, and biomarkers of a single dose of ATA3219 administered to LN subjects refractory to one or more lines of treatment. Subjects will receive lymphodepletion treatment followed by ATA3219 at a dose of 40, 80, or 160 x 10 6 CAR+ T cells. Each dose level is designed to enroll 3-6 subjects Atara is positioned to potentially expand ATA3219 Phase 1 study into additional autoimmune indications via the same Investigational New Drug (IND) application previously cleared for the LN study Preclinical data supporting the potential of ATA3219 in SLE was presented in poster presentation at the International Society for Cell & Gene Therapy meeting. The data demonstrated that ATA3219 CAR T cells led to complete CD19-specific B-cell depletion against SLE or multiple sclerosis patient peripheral blood mononuclear cells Additional preclinical data presented in the poster showed that ATA3219 CAR T cells, which incorporate the next-generation 1XX costimulatory domain, released lower levels of pro-inflammatory cytokines while maintaining cytotoxic function and potency in response to stimulation with CD19+ target cells when compared to autologous CAR T controls. Mitigating inflammatory cytokine release that is typically seen with standard CD19 CAR T signaling may lead to reduced toxicity and better tolerability if confirmed in clinical trials ATA3219: CD19 Program in Severe Systemic Lupus Erythematosus (SLE) Without Lymphodepletion Atara plans to expand the Phase 1 LN study of ATA3219 and add a new cohort in severe SLE without lymphodepletion (LD) in Q4 2024 with initial clinical data anticipated in mid-2025 Eligible subjects with severe SLE will receive ATA3219 at a dose of 40, 80, or 240 × 10 6 CAR+ T cells The elimination of LD is designed to further simplify the treatment regimen and to potentially provide a differentiated safety profile to patients without comprising efficacy which may improve patient access There is compelling clinical and scientific rationale supporting the potential to eliminate the need for LD based on the EBV T-cell backbone and unique features of ATA3219, including: 1) low alloreactivity risk and favorable safety in over 600 patients treated without LD, due to T-cell receptor EBV specificity and partial human leukocyte antigen matching; 2) expansion and persistence data without LD correlating to efficacy in patients treated with tab-cel; and 3) the inclusion of clinically validated features into ATA3219 such as the 1XX costimulatory domain and memory phenotype that increase potency and persistence ATA3219: CD19 Program in Non-Hodgkin’s Lymphoma (NHL) Atara continues opening sites and initiating enrollment of a multi-center, Phase 1 open-label, dose-escalation clinical trial of ATA3219 in NHL, including large B-cell lymphomas, follicular lymphoma, and mantle cell lymphoma, with initial clinical data anticipated in Q1 2025 Study designed to evaluate safety, preliminary efficacy, pharmacokinetics, and biomarkers. Subjects will receive LD treatment followed by ATA3219 at a dose of 40, 80, 240, or 480 x 10 6 CAR+ T cells. Each dose level is designed to enroll 3-6 patients Previously presented preclinical data demonstrated superior in vivo persistence and CD19-specific anti-tumor efficacy compared to an autologous CD19 CAR T benchmark with no observed toxicity or alloreactivity ATA3431 : CD19/CD20 Program for B-Cell Malignancies Preclinical data presented at ASH 2023 demonstrated early evidence of potent antitumor activity, long-term persistence, and superior tumor growth inhibition compared to an autologous CD19/CD20 CAR T benchmark Dual CD19 and CD20 targeting designed to address CD19 escape and tumor variability and may provide additional efficacy in lymphoma Atara is progressing toward an IND submission in H2 2025 Leadership Updates Effective September 9, 2024: Cokey Nguyen, Ph.D., the Company's current Chief Scientific and Technical Officer, will be promoted to the role of President and CEO and Pascal Touchon, the Company's current President and CEO, will transition to the role of Chairman of the Board of Directors Cokey Nguyen, Ph.D., will be appointed to the Company’s Board of Directors Carol Gallagher, Pharm.D., current Chair of the Board, will transition to become Independent Lead Director Second Quarter 2024 Financial Results Cash, cash equivalents and short-term investments as of June 30, 2024 totaled $35.3 million, as compared to $46.2 million as of March 31, 2024 Q2 2024 accounts receivable totaled $2.4 million; however, this amount does not include the $20 million milestone payment owed by Pierre Fabre related to the tab-cel BLA acceptance, which was received in August 2024 On August 9, 2024, Pierre Fabre and Atara entered into an agreement for Pierre Fabre to purchase certain existing tab-cel intermediate inventory from Atara for $15.5 million, which is expected to be received from Pierre Fabre in September 2024 Together, cash, cash equivalents, short-term investments, accounts receivable as of June 30, 2024, the $20 million tab-cel BLA acceptance milestone payment, and the $15.5 million tab-cel intermediate inventory purchase amount total $73.2 million Net cash used in operating activities was $10.6 million for the second quarter 2024, as compared to $52.8 million in the same period in 2023 Q2 2024 net cash used in operating activities included a $20 million cash payment received from Pierre Fabre for a milestone payment achieved in March 2024, whereas Q2 2023 had no such cash receipts Total revenues were $28.6 million for the second quarter 2024, as compared to $1.0 million for the same period in 2023. Total revenues increased by $27.6 million year over year, primarily due to revenue recognized as a result of additional obligations for the expanded partnership with Pierre Fabre and accelerated recognition of existing deferred revenue due to the planned transition of substantially all activities relating to tab-cel at the time of BLA approval and transfer to Pierre Fabre Total costs and operating expenses include non-cash stock-based compensation, depreciation and amortization expenses of $7.7 million for the second quarter 2024, as compared to $13.8 million for the same period in 2023 Research and development expenses were $33.3 million for the second quarter 2024, as compared to $56.1 million for the same period in 2023 Research and development expenses include $3.3 million of non-cash stock-based compensation expenses for the second quarter 2024, as compared to $7.2 million for the same period in 2023 General and administrative expenses were $8.9 million for the second quarter 2024, as compared to $13.3 million for the same period in 2023 General and administrative expenses include $3.0 million of non-cash stock-based compensation expenses for the second quarter 2024, as compared to $5.4 million for the same period in 2023 Atara reported net losses of $19.0 million, or $3.10 per share, for the second quarter 2024, as compared to $71.1 million, or $16.91 per share, for the same period in 2023 2024 Outlook and Cash Runway Atara expects full year 2024 operating expenses to decrease by approximately 35% from 2023 The large majority of the year-over-year operating expense reduction began in Q2 2024 and is expected to continue for the remainder of the year Atara expects that cash, cash equivalents, short-term investments, and accounts receivable as of June 30, 2024, plus the items noted below, in total will enable funding of planned operations into 2027: $20 million milestone payment for the acceptance of the tab-cel BLA received from Pierre Fabre in August 2024 and $60 million contingent upon the approval of the tab-cel BLA; $15.5 million purchase by Pierre Fabre of tab-cel intermediate inventory to be received in September 2024 and additional anticipated purchases of tab-cel inventory through the manufacturing transfer date by Pierre Fabre; anticipated reimbursement for tab-cel global development costs through the BLA transfer by Pierre Fabre; operating efficiencies resulting from completed workforce reductions; the planned transition of substantially all activities relating to tab-cel at the time of the BLA transfer to Pierre Fabre potentially as early as Q1 2025, which will further reduce quarterly operating expenses; and anticipated royalties from sales of tab-cel by Pierre Fabre in the U.S. post BLA approval About ATA3219 ATA3219 combines the natural biology of unedited T cells with the benefits of an allogeneic therapy. It consists of allogeneic Epstein-Barr virus (EBV)-sensitized T cells that express a CD19 CAR construct for the treatment of CD19+ relapsed or refractory B-cell malignancies, including B-cell non-Hodgkin’s lymphoma and B-cell mediated autoimmune diseases including systemic lupus erythematosus. ATA3219 has been optimized to offer a potential best-in-class profile, featuring off-the-shelf availability. It incorporates multiple clinically validated technologies including a modified CD3ζ signaling domain (1XX) that optimizes expansion and mitigates exhaustion, enrichment during manufacturing for a less differentiated phenotype for robust expansion and persistence and retains the endogenous T-cell receptor without gene editing as a key survival signal for T cells contributing to persistence. About ATA3431 ATA3431 is an allogeneic, bispecific CAR directed against CD20 and CD19, built on Atara’s EBV T-cell platform. The design consists of a tandem CD20-CD19 design, with binders oriented to optimize potency. Dual targets address the limitations of single antigen loss and tumor variability. ATA3431 features a novel 1XX costimulatory domain, memory phenotype, and retained, unedited T-cell receptor. Preclinical data have demonstrated early evidence of antitumor activity, long-term persistence, and superior tumor growth inhibition compared to an autologous CD19/CD20 CAR T benchmark. Next-Generation Allogeneic CAR T Approach Atara is focused on applying Epstein-Barr virus (EBV) T-cell biology, featuring experience in over 600 patients treated with allogeneic EBV T cells, and novel chimeric antigen receptor (CAR) technologies to meet the current limitations of autologous and allogeneic CAR therapies head-on by advancing a potential best-in-class CAR T pipeline in oncology and autoimmune disease. Unlike gene-edited approaches aimed at inactivating T-cell receptor (TCR) function to reduce the risk for graft-vs-host disease, Atara’s allogeneic platform maintains expression of the native EBV TCR that promote in vivo functional persistence while also demonstrating inherently low alloreactivity due to their recognition of defined viral antigens and partial human leukocyte antigen (HLA) matching. A molecular toolkit of clinically-validated technologies—including the 1XX costimulatory domain designed for better cell fitness and less exhaustion while maintaining stemness—offers a differentiated approach to addressing significant unmet need with the next generation CAR T. About Atara Biotherapeutics, Inc. Atara is harnessing the natural power of the immune system to develop off-the-shelf cell therapies for difficult-to-treat cancers and autoimmune conditions that can be rapidly delivered to patients from inventory. With cutting-edge science and differentiated approach, Atara is the first company in the world to receive regulatory approval of an allogeneic T-cell immunotherapy. Our advanced and versatile T-cell platform does not require T-cell receptor or HLA gene editing and forms the basis of a diverse portfolio of investigational therapies that target EBV, the root cause of certain diseases, in addition to next-generation AlloCAR-Ts designed for best-in-class opportunities across a broad range of hematological malignancies and B-cell driven autoimmune diseases. Atara is headquartered in Southern California. For more information, visit atarabio.com and follow @Atarabio on X and LinkedIn . Forward-Looking Statements This press release contains or may imply "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. For example, forward-looking statements include statements regarding: (1) the development, timing and progress of tab-cel ® , including the BLA and potential indications, the potential characteristics and benefits of tab-cel ® , and the progress and results of, and prospects for, the global partnership with Pierre Fabre Laboratories involving tab-cel ® , and the potential financial benefits to Atara as a result of the global partnership with Pierre Fabre Laboratories, including the receipt, timing and amount of any payments to be received by Atara thereunder; (2) the development, timing and progress of Atara’s AlloCAR-T programs (including ATA3219 and ATA3431), including the timing of the start of any clinical trials, the timing of the availability of data from such clinical trials, the timing of submissions of regulatory applications, and the potential benefits, characteristics, safety and efficacy of such product candidates or product candidates emerging from such programs; (3) Atara’s cash runway, the timing and receipt of potential milestone and other payments, and operating expenses, including Atara’s ability to fund its planned operations into 2027; and (4) Atara’s planned transition of substantially all activities relating to tab-cel at the time of the BLA transfer to Pierre Fabre and the timing thereof. Because such statements deal with future events and are based on Atara’s current expectations, they are subject to various risks and uncertainties and actual results, performance or achievements of Atara could differ materially from those described in or implied by the statements in this press release. These forward-looking statements are subject to risks and uncertainties, including, without limitation, risks and uncertainties associated with the costly and time-consuming pharmaceutical product development process and the uncertainty of clinical success; the COVID-19 pandemic and the wars in Ukraine and the Middle East, which may significantly impact (i) our business, research, clinical development plans and operations, including our operations in Southern California and Denver and at our clinical trial sites, as well as the business or operations of our third-party manufacturer, contract research organizations or other third parties with whom we conduct business, (ii) our ability to access capital, and (iii) the value of our common stock; the sufficiency of Atara’s cash resources and need for additional capital; and other risks and uncertainties affecting Atara’s and its development programs, including those discussed in Atara’s filings with the Securities and Exchange Commission, including in the “Risk Factors” and “ Management’s Discussion and Analysis of Financial Condition and Results of Operations” sections of the Company’s most recently filed periodic reports on Form 10-K and Form 10-Q and subsequent filings and in the documents incorporated by reference therein. Except as otherwise required by law, Atara disclaims any intention or obligation to update or revise any forward-looking statements, which speak only as of the date hereof, whether as a result of new information, future events or circumstances or otherwise. Financials ATARA BIOTHERAPEUTICS, INC. Condensed Consolidated Balance Sheets (Unaudited) (In thousands) June 30, December 31, 2024 2023 Assets Current assets: Cash and cash equivalents $ 31,314 $ 25,841 Short-term investments 3,978 25,884 Restricted cash 146 146 Accounts receivable 2,422 34,108 Inventories 18,749 9,706 Other current assets 5,801 6,184 Total current assets 62,410 101,869 Property and equipment, net 2,317 3,856 Operating lease assets 48,948 54,935 Other assets 3,609 4,844 Total assets $ 117,284 $ 165,504 Liabilities and stockholders’ equity (deficit) Current liabilities: Accounts payable $ 5,253 $ 3,684 Accrued compensation 7,269 11,519 Accrued research and development expenses 2,014 17,364 Deferred revenue 107,582 77,833 Other current liabilities 26,149 31,826 Total current liabilities 148,267 142,226 Deferred revenue - long-term 567 37,562 Operating lease liabilities - long-term 38,703 45,693 Liability related to the sale of future revenues - long-term 36,448 34,623 Other long-term liabilities 4,167 4,631 Total liabilities $ 228,152 $ 264,735 Stockholders’ (deficit) equity: Common stock — — Additional paid-in capital 1,909,097 1,870,123 Accumulated other comprehensive loss (14 ) (204 ) Accumulated deficit (2,019,951 ) (1,969,150 ) Total stockholders’ (deficit) equity (110,868 ) (99,231 ) Total liabilities and stockholders’ (deficit) equity $ 117,284 $ 165,504 ATARA BIOTHERAPEUTICS, INC. Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) (In thousands, except per share amounts) Three Months Ended June 30, Six Months Ended June 30, 2024 2023 2024 2023 Commercialization revenue $ 28,640 $ 793 $ 55,997 $ 1,677 License and collaboration revenue — 164 — 506 Total revenue 28,640 957 55,997 2,183 Costs and operating expenses: Cost of commercialization revenue 4,627 2,895 6,612 3,111 Research and development expenses 33,332 56,141 78,838 118,297 General and administrative expenses 8,912 13,335 20,025 27,207 Total costs and operating expenses 46,871 72,371 105,475 148,615 Loss from operations (18,231 ) (71,414 ) (49,478 ) (146,432 ) Interest and other income (expense), net (818 ) 307 (1,299 ) 576 Loss before provision for income taxes (19,049 ) (71,107 ) (50,777 ) (145,856 ) Provision for income taxes — 1 24 23 Net loss $ (19,049 ) $ (71,108 ) $ (50,801 ) $ (145,879 ) Other comprehensive gain (loss): Unrealized gain (loss) on available-for-sale securities 41 304 190 1,134 Comprehensive loss $ (19,008 ) $ (70,804 ) $ (50,611 ) $ (144,745 ) Basic and diluted net loss per common share $ (3.10 ) $ (16.91 ) $ (8.64 ) $ (34.89 ) Basic and diluted weighted-average shares outstanding 6,143 4,204 5,883 4,181