Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2025 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES ACT OF 1934 For the transition period from ____________ to ____________ Commission File Number: 001-12584 THERIVA BIOLOGICS, INC. (Exact name of registrant as specified in its charter) Nevada 13- ...

Exhibit 99.1 Theriva™ Biologics Reports Second Quarter 2025 Operational Highlights and Financial Results - Released positive topline data from the VIRAGE Phase 2b study of VCN-01 (zabilugene almadenorepvec); expanded data to be presented at the European Society for Medical Oncology (ESMO) 2025 Congress in October - - VCN-01 demonstrates potential in retinoblastoma with Phase 1 safety and clinical outcome data presented at the American Society of Clinical Oncology (ASCO) 2025 Annual Meeting - - Cash and cash ...

Core Insights - Theriva Biologics is set to present safety and clinical outcomes from a Phase 1 study of VCN-01 in refractory retinoblastoma patients at the ASCO Annual Meeting in Chicago on May 31, 2025 [1][3] - The company will also review topline data from the VIRAGE Phase 2b clinical trial of VCN-01 in first-line metastatic pancreatic ductal adenocarcinoma (PDAC) during the ASCO conference [1][4] Company Overview - Theriva Biologics is a diversified clinical-stage company focused on developing therapeutics for cancer and related diseases, particularly in areas with high unmet medical needs [1][9] - The company's lead candidate, VCN-01 (zabilugene almadenorepvec), is an oncolytic adenovirus designed to selectively replicate within tumor cells and degrade tumor stroma, enhancing the efficacy of co-administered therapies [5][9] Clinical Study Details - The Phase 1 clinical study evaluated the safety and tolerability of two intravitreal injections of VCN-01 in patients with intraocular retinoblastoma who were refractory to other treatments [1][6] - The study was conducted at Sant Joan de Déu Barcelona Children's Hospital, and the results are expected to provide insights into the long-term efficacy of VCN-01 in this pediatric cancer population [3][6] Expert Commentary - Guillermo Chantada, an expert in retinoblastoma, highlighted VCN-01's promising safety profile and its potential to address treatment failures in refractory cases [3] - The oncolytic virus specifically targets tumor cells and is of particular interest due to its non-chemotherapeutic nature, which may reduce the risk of treatment-induced malignancies in children [3] Market Context - Retinoblastoma is the most common type of eye cancer in children, with an incidence rate of approximately 1 in 14,000 to 1 in 18,000 live newborns [8] - The average age of diagnosis is around 2 years, and the disease poses significant challenges in preserving life and preventing severe treatment-related complications [8]

Financial Performance - The net loss for the three months ended March 31, 2025, was $4.3 million, or ($1.55) per common share, compared to a net loss of $5.2 million, or ($7.53) per common share for the same period in 2024[229]. - Cash and cash equivalents totaled $10.0 million as of March 31, 2025, a decrease of $1.6 million from December 31, 2024[231]. - The accumulated deficit was $339.3 million as of March 31, 2025, with expectations of continued losses in the foreseeable future[230]. - Cash used in operating activities was $4.8 million during the three months ended March 31, 2025, compared to $4.9 million for the same period in 2024[236]. - Total research and development expenses for the three months ended March 31, 2025, were $2.968 million, down from $3.459 million in 2024[227]. - Research and development expenses decreased to $3.0 million for the three months ended March 31, 2025, from approximately $3.5 million for the same period in 2024, a decrease of 14%[225]. - General and administrative expenses decreased to $1.4 million for the three months ended March 31, 2025, from $1.9 million for the same period in 2024, a decrease of 25%[224]. - Cash provided by financing activities during the three months ended March 31, 2025, included $1.7 million received for the research and development tax credit[238]. - As of early May 2025, cash position was $14.1 million, expected to fund operations into the first quarter of 2026[232]. - Future clinical trials for VCN-01, SYN-004, and SYN-020 will require significant financing, and the company does not currently have committed sources of funding[235]. Clinical Trials and Product Development - The lead product candidate, VCN-01, is currently in a Phase 2b clinical study for pancreatic cancer, with positive topline outcomes indicating a median overall survival (OS) of 10.8 months for patients receiving VCN-01 plus standard-of-care chemotherapy compared to 8.6 months for those receiving standard care alone[145][149]. - In the VIRAGE trial, patients receiving two doses of VCN-01 showed a median OS of 14.8 months compared to 11.6 months for those receiving standard care, suggesting a significant benefit from the additional dose[146]. - The Phase 2b clinical trial of VCN-01 in combination with nab-paclitaxel and gemcitabine is ongoing, with additional studies evaluating VCN-01 in other cancer types[154]. - The Phase 2b clinical trial VIRAGE for VCN-01 in combination with gemcitabine and nab-paclitaxel has enrolled 92 evaluable patients, achieving the target enrollment by September 23, 2024[157]. - Topline data for the VIRAGE Phase 2b clinical trial is anticipated for Q2 2025[157]. - The FDA granted Fast Track Designation to VCN-01 in combination with gemcitabine and nab-paclitaxel to improve progression-free survival and overall survival in patients with metastatic pancreatic adenocarcinoma on May 23, 2024[161]. - An Independent Data Monitoring Committee confirmed that VCN-01 was well tolerated in the Phase 2b trial, with adverse events consistent with prior trials and less frequent after the second dose[164]. - The clinical trial for VCN-01 in retinoblastoma showed positive topline data, with no dose-limiting toxicities and treatment-related adverse events primarily Grade 1 or 2[165][166]. - The Phase 1 trial combining VCN-01 with durvalumab showed well-tolerated results, with sustained blood levels of VCN-01 and increased tumor inflammation markers[173]. - The ongoing studies suggest that VCN-01 may enhance the potential antitumor effects of co-administered huCART-meso cells in patients with unresectable or metastatic pancreatic adenocarcinoma[176]. - The Phase 1 trial of huCART-meso cells combined with VCN-01 showed overall survival (OS) of 10.4 months in the concomitant cohort and 15.5 months in the sequential cohort at a dose of 3.3×10^12 viral particles (vp), with OS reaching 17.3 months at a dose of 1×10^13 vp[178]. - 61.1% of patients (11 out of 18) were alive for more than 12 months, indicating a promising trend in disease stabilization[178]. - VCN-01 demonstrated biological activity with replication observed and increased serum hyaluronidase levels maintained for over six weeks[178]. - The safety profile of VCN-01 was consistent with expectations from monotherapy studies, with 66.6% of patients showing tumor shrinkage when receiving huCART-meso after VCN-01[179]. - A new next-generation mesothelin-specific CAR-T is being developed, which may be evaluated in combination with VCN-01 in future clinical trials[180]. - The Phase 1 clinical study of SYN-004 (ribaxamase) aims to prevent antibiotic-mediated microbiome damage and is currently in a randomized, double-blinded, placebo-controlled trial with 36 evaluable adult allogeneic HCT recipients[186][187]. - SYN-020, a recombinant version of bovine Intestinal Alkaline Phosphatase, is being developed to mitigate intestinal damage caused by radiation therapy, with production costs anticipated to be significantly lower than current market rates[192]. - The Phase 1 clinical study of SYN-020 demonstrated a favorable safety profile with no serious adverse events reported, and it was well tolerated across all dose levels[196]. - The company has received a study-may-proceed letter from the FDA for SYN-020, allowing for further clinical development[195]. - Phase 1 data from SAD and MAD studies support the development of SYN-020 for multiple clinical indications, including NAFLD and aging-related diseases[198]. Funding and Grants - The company completed a public offering on May 8, 2025, raising approximately $7.5 million through the sale of 1,990,900 shares of Common Stock and warrants[134]. - The company received €2.28 million (approximately $2.54 million) from the Spanish government's National Knowledge Transfer Program to support the THERICEL project, which includes a €1.3 million loan and a €0.95 million grant[139]. - The company received $1.7 million from the 2023 Research and Development rebate program sponsored by the Spanish government[138]. Intellectual Property and Licensing - The company is exploring value creation options for its previous assets, SYN-004 and SYN-020, including out-licensing or partnering[133]. - The ongoing clinical trials and product developments are supported by a growing intellectual property portfolio, with efforts to maintain and build patent applications[183]. - The company has over 130 U.S. and foreign patents and over 65 patents pending, supporting its various programs[208]. - The SYN-004 program is supported by patents that will expire in at least 2031, covering compositions of matter and uses of beta-lactamases[209]. - The VCN-01 and VCN-11 programs are supported by patents that provide coverage for engineered oncolytic adenoviruses, with some patents expiring as late as 2037[211]. - The company entered into an agreement with Massachusetts General Hospital for an exclusive license related to IAP technology, which expired unexercised on July 1, 2024[197]. Manufacturing and Development - The THERICEL program is advancing a proprietary A549 suspension cell line to enhance the efficiency and reduce the cost of manufacturing VCN-01 for clinical trials[205]. - Preclinical data indicated that the ABD-containing virus VCN-11 induced 450 times more cytotoxicity in tumor cells compared to normal cells, demonstrating a low toxicity profile[203].

[Theriva™ Biologics First Quarter 2025 Report](index=1&type=section&id=Theriva%E2%84%A2%20Biologics%20Reports%20First%20Quarter%202025%20Operational%20Highlights%20and%20Financial%20Results) [Recent Highlights and Anticipated Milestones](index=1&type=section&id=Recent%20Highlights%20and%20Anticipated%20Milestones) Theriva Biologics achieved key clinical milestones in early 2025, including positive Phase 2b results for VCN-01 and SYN-004 data presentation - The VIRAGE Phase 2b clinical trial of VCN-01 achieved its primary survival and safety endpoints in patients with newly diagnosed metastatic pancreatic cancer[2](index=2&type=chunk) - The company is preparing for a potential Phase 3 trial of VCN-01 by scaling up manufacturing and finalizing the trial design[2](index=2&type=chunk)[3](index=3&type=chunk) - Data from a Phase 1b/2a trial of SYN-004 for preventing acute graft-versus-host-disease (aGVHD) was presented at the ESCMID Global congress in April[4](index=4&type=chunk) [VCN-01 for Metastatic Pancreatic Ductal Adenocarcinoma (mPDAC)](index=1&type=section&id=VCN-01) The VIRAGE Phase 2b trial of VCN-01 showed improved survival and response rates in mPDAC patients, with good tolerability - Patients treated with VCN-01 plus standard-of-care chemotherapy showed increased **overall survival (OS)**, **progression-free survival (PFS)**, and **duration of response (DOR)** compared to the control group[3](index=3&type=chunk) - VCN-01 was well-tolerated, with adverse events being transient and reversible[3](index=3&type=chunk) - Patients receiving two doses of VCN-01 showed a greater increase in OS, suggesting an additional benefit from the second dose[3](index=3&type=chunk) [SYN-004 for Allogeneic Hematopoietic Cell Transplant (HCT)](index=2&type=section&id=SYN-004) Phase 1b/2a trial data for SYN-004 in preventing aGVHD in HCT recipients was presented at ESCMID Global - Data from a Phase 1b/2a trial of SYN-004 for the prevention of acute graft-versus-host-disease (aGVHD) in allogeneic HCT recipients was presented at the ESCMID Global congress[4](index=4&type=chunk) [Q1 2025 Financial Results and Corporate Update](index=2&type=section&id=First%20Quarter%20Ended%20March%2031%2C%202025%20Financial%20Results) Theriva Biologics reduced Q1 2025 net loss to $4.3 million and extended cash runway into Q1 2026 through a $7.5 million public offering Q1 2025 vs Q1 2024 Operating Expenses (in millions) | Expense Category | Q1 2025 | Q1 2024 | Change | | :--- | :--- | :--- | :--- | | General and administrative | $1.4 | $1.9 | -25% | | Research and development | $3.0 | $3.5 | -14% | - Net loss for Q1 2025 was **$4.3 million**, compared to a net loss of **$5.2 million** for Q1 2024[20](index=20&type=chunk) - Closed a public offering on May 8, 2025, raising gross proceeds of approximately **$7.5 million**, increasing the cash balance to **$14.1 million** and expected to fund operations into Q1 2026[1](index=1&type=chunk)[9](index=9&type=chunk)[10](index=10&type=chunk) [Financial Statements](index=5&type=section&id=Financial%20Statements) The Q1 2025 unaudited financial statements show total assets of $32.2 million, liabilities of $16.7 million, and a net loss of $4.3 million [Condensed Consolidated Balance Sheets](index=5&type=section&id=Condensed%20Consolidated%20Balance%20Sheets) As of March 31, 2025, total assets were $32.2 million, total liabilities $16.7 million, and stockholders' equity $15.5 million Balance Sheet Summary (in thousands) | Account | March 31, 2025 | December 31, 2024 | | :--- | :--- | :--- | | Cash and cash equivalents | $10,014 | $11,609 | | Total Current Assets | $12,476 | $16,281 | | Total Assets | $32,161 | $35,352 | | Total Current Liabilities | $8,148 | $7,585 | | Total Liabilities | $16,664 | $16,285 | | Total Stockholders' Equity | $15,497 | $19,067 | [Condensed Consolidated Statements of Operations](index=6&type=section&id=Condensed%20Consolidated%20Statements%20of%20Operations%20and%20Comprehensive%20Loss) Q1 2025 net loss was $4.3 million ($1.55 per share), an improvement from $5.2 million ($7.53 per share) in Q1 2024 Statement of Operations Summary (in thousands, except per share data) | Metric | Q1 2025 | Q1 2024 | | :--- | :--- | :--- | | Total Operating Costs and Expenses | $4,417 | $5,392 | | Loss from Operations | ($4,417) | ($5,392) | | Net Loss | ($4,324) | ($5,165) | | Net Loss Per Share - Basic and Dilutive | ($1.55) | ($7.53) | [Company and Product Information](index=3&type=section&id=Company%20and%20Product%20Information) This section details Pancreatic Ductal Adenocarcinoma, the VIRAGE trial design, VCN-01's mechanism, and Theriva's therapeutic pipeline [About Pancreatic Ductal Adenocarcinoma (PDAC)](index=3&type=section&id=About%20Pancreatic%20Ductal%20Adenocarcinoma) PDAC, accounting for over 90% of pancreatic tumors, is often diagnosed late with high rates of metastasis - PDAC accounts for more than **90%** of all pancreatic tumors and is often diagnosed late, with **50-60%** of patients presenting with distant metastases[11](index=11&type=chunk) [About VIRAGE Trial](index=3&type=section&id=About%20VIRAGE) The VIRAGE trial was a Phase 2b, randomized, controlled study evaluating VCN-01 plus chemotherapy in mPDAC patients - The VIRAGE trial was a two-arm, Phase 2b, randomized, controlled study in newly-diagnosed metastatic PDAC patients, with primary endpoints of overall survival and safety[12](index=12&type=chunk) [About VCN-01](index=3&type=section&id=About%20VCN-01) VCN-01 is an oncolytic adenovirus that selectively targets tumor cells, degrades stroma, and enhances chemotherapy effects - VCN-01 is an oncolytic adenovirus that selectively lyses tumor cells, degrades the tumor stroma, and enhances the effect of co-administered therapies[13](index=13&type=chunk) [About Theriva™ Biologics, Inc.](index=4&type=section&id=About%20Theriva%E2%84%A2%20Biologics%2C%20Inc.) Theriva Biologics is a clinical-stage company developing VCN-01, SYN-004, and SYN-020 for cancer and other diseases - Theriva's lead candidates are **VCN-01** (oncolytic adenovirus), **SYN-004** (ribaxamase for GI tract protection), and **SYN-020** (recombinant oral IAP)[14](index=14&type=chunk)

Core Viewpoint - Theriva Biologics has successfully closed a public offering, raising approximately $7.5 million to support its cancer therapeutics development and other corporate purposes [1][2]. Group 1: Offering Details - The public offering consisted of 6,818,180 shares of common stock and warrants to purchase an equal number of shares at a combined price of $1.10 per share [1]. - The warrants are exercisable immediately and will expire five years from the issuance date [1]. - The offering was conducted under a registration statement that was declared effective by the SEC on May 7, 2025 [3]. Group 2: Use of Proceeds - The net proceeds from the offering will primarily be used for working capital, general corporate purposes, research and development, and manufacturing scale-up [2]. - The company may also consider investing in or acquiring other products, businesses, or technologies, although no commitments currently exist [2]. Group 3: Company Overview - Theriva Biologics is a clinical-stage company focused on developing therapeutics for cancer and related diseases, with a particular emphasis on high unmet medical needs [5]. - The company's lead candidates include VCN-01, SYN-004, and SYN-020, targeting various aspects of cancer treatment and gastrointestinal health [5].

Core Viewpoint - Theriva Biologics announced a public offering of up to 6,818,180 shares of common stock and warrants, aiming to raise approximately $7.5 million for working capital and R&D purposes [1][2]. Group 1: Offering Details - The offering price is set at $1.10 per share and accompanying warrant, with warrants exercisable immediately and expiring five years from issuance [1]. - The closing of the offering is expected on or about May 8, 2025, pending customary closing conditions [2]. - A.G.P./Alliance Global Partners is acting as the sole placement agent for the offering [3]. Group 2: Use of Proceeds - The net proceeds from the offering will primarily be used for working capital and general corporate purposes, including research and development and manufacturing scale-up [2]. - The company may also consider using a portion of the proceeds for investments or acquisitions, although no commitments currently exist [2]. Group 3: Company Overview - Theriva Biologics is a clinical-stage company focused on developing therapeutics for cancer and related diseases, with a particular emphasis on high unmet medical needs [6]. - The company's lead candidates include VCN-01, SYN-004, and SYN-020, targeting various aspects of cancer treatment and microbiome protection [6].

Core Insights - Theriva Biologics announced positive topline outcomes from the VIRAGE Phase 2b clinical trial for VCN-01 in combination with standard-of-care chemotherapy for metastatic pancreatic ductal adenocarcinoma (PDAC) patients [1][3] Company Overview - Theriva Biologics is a diversified clinical-stage company focused on developing therapeutics for cancer and related diseases, with its lead product candidate being VCN-01, an oncolytic adenovirus [10][11] Clinical Trial Results - The VIRAGE trial involved 96 newly-diagnosed metastatic PDAC patients, showing that patients receiving 2 doses of VCN-01 plus chemotherapy had a median overall survival (OS) of 14.8 months compared to 11.6 months for those receiving chemotherapy alone [2] - In the primary endpoint analysis, patients treated with VCN-01 followed by chemotherapy had a median OS of 10.8 months, while those receiving only chemotherapy had a median OS of 8.6 months [5] - The trial demonstrated increased progression-free survival (PFS) and duration of response (DoR) in the VCN-01 treatment group, with median PFS of 7.0 months compared to 4.6 months for the control group [5] Safety Profile - VCN-01 was well-tolerated, with adverse events being transient and reversible, consistent with prior clinical trials [3][4] - The most common adverse events included pyrexia, flu-like illness, and elevated transaminases, which were less frequent after the second dose of VCN-01 [3] Future Directions - The positive data from the VIRAGE trial is expected to facilitate engagement with industry partners and support the design of a Phase 3 confirmatory trial [3][4]

Core Viewpoint - Theriva Biologics is presenting interim blinded safety and pharmacokinetic data for SYN-004 at the ESCMID Global Congress, focusing on its potential to prevent acute graft-versus-host disease in allogeneic hematopoietic cell transplant recipients [1][3]. Group 1: Clinical Trial Details - The ongoing Phase 1b/2a clinical trial is randomized, double-blinded, and placebo-controlled, evaluating the safety and tolerability of oral SYN-004 in allogeneic HCT recipients receiving IV antibiotics [3]. - The trial is being conducted at Washington University School of Medicine and aims to enroll up to 36 participants across three cohorts, each receiving different IV beta-lactam antibiotics [3]. - Safety and pharmacokinetic data are reviewed by an independent Data and Safety Monitoring Committee to determine the progression to the next cohort [3]. Group 2: About SYN-004 - SYN-004 (ribaxamase) is designed to degrade certain IV beta-lactam antibiotics in the gastrointestinal tract, maintaining gut microbiome balance and preventing Clostridioides difficile infection and acute graft-versus-host disease [4][6]. - A previous Phase 2b clinical trial with 412 patients showed that SYN-004 protected the gut microbiome from antibiotic-mediated dysbiosis, leading to better maintenance and recovery of the microbiome [4]. Group 3: Company Overview - Theriva Biologics is a diversified clinical-stage company focused on developing therapeutics for cancer and related diseases, with a subsidiary working on an oncolytic adenovirus platform [5][6]. - The company's lead candidates include VCN-01, SYN-004, and SYN-020, targeting various aspects of cancer treatment and microbiome protection [6].

Company Overview - Theriva™ Biologics is a diversified clinical-stage company focused on developing therapeutics for cancer and related diseases in areas of high unmet need [3] - The company is advancing a new oncolytic adenovirus platform for intravenous, intravitreal, and antitumoral delivery to enhance tumor cell death and improve access to co-administered cancer therapies [3] Lead Candidates - The lead candidates include: - VCN-01, an oncolytic adenovirus that selectively replicates within tumor cells and degrades the tumor stroma barrier [3] - SYN-004 (ribaxamase), designed to degrade certain IV beta-lactam antibiotics in the gastrointestinal tract to prevent microbiome damage and reduce acute graft-versus-host disease in transplant recipients [3] - SYN-020, a recombinant oral formulation of intestinal alkaline phosphatase intended to treat local GI and systemic diseases [3] Upcoming Conference Participation - Theriva's management will present at the Cancer Advocacy Group of Louisiana NeauxCancer 2025 Conference from March 27th-29th, 2025 [1] - A company presentation is scheduled for the Innovation track on March 28th at 9:00 am, highlighting emerging biotech and healthcare companies in oncology [2] - Management will be available for one-on-one meetings with interested investors during the conference [2]