# EDGAR Filing Document

**Accession Number:** 0000894158
**File Stem:** 0001104659-25-100608
**Filing Date:** 2025-10
**Character Count:** 18792
**Document Hash:** 8d01c5dfed9bdf2cf40a6cee04aed605
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-25-100608.hdr.sgml**: 20251020

**ACCESSION NUMBER**: 0001104659-25-100608

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 28

**CONFORMED PERIOD OF REPORT**: 20251020

**ITEM INFORMATION**: Other Events

**ITEM INFORMATION**: Financial Statements and Exhibits

**FILED AS OF DATE**: 20251020

**DATE AS OF CHANGE**: 20251020

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Theriva Biologics, Inc.
- **CENTRAL INDEX KEY:** 0000894158
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 133808303
- **STATE OF INCORPORATION:** NV
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-12584
- **FILM NUMBER:** 251402317

**BUSINESS ADDRESS:**
- **STREET 1:** 9605 MEDICAL CENTER DRIVE
- **STREET 2:** SUITE 270
- **CITY:** ROCKVILLE
- **STATE:** MD
- **ZIP:** 20850
- **BUSINESS PHONE:** (734) 332-7800

**MAIL ADDRESS:**
- **STREET 1:** 9605 MEDICAL CENTER DRIVE
- **STREET 2:** SUITE 270
- **CITY:** ROCKVILLE
- **STATE:** MD
- **ZIP:** 20850

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Synthetic Biologics, Inc.
- **DATE OF NAME CHANGE:** 20120305

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** ADEONA PHARMACEUTICALS, INC.
- **DATE OF NAME CHANGE:** 20081027

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** PIPEX PHARMACEUTICALS, INC.
- **DATE OF NAME CHANGE:** 20061214

?xml version='1.0' encoding='ASCII'?

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**WASHINGTON, D.C. 20549**

**FORM 8-K**

**CURRENT REPORT**

**Pursuant to Section 13 or 15(d)**

**of the Securities Exchange Act of 1934**

**Date of Report (Date of earliest event reported): October 20, 2025**

**THERIVA BIOLOGICS, INC.**

(Exact name of registrant as specified in its charter)

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| | | |
|:---|:---|:---|
| **Nevada** | **001-12584** | **13-3808303** |
| (State or other jurisdiction of<br> incorporation) | (Commission File No.) | (IRS Employer Identification<br> No.) |

---

**9605 Medical Center Drive, Suite 270**

**Rockville, Maryland 20850**

(Address of principal executive offices and zip code)

**(301) 417-4364**

Registrant's telephone number, including area code

**N/A**

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

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| |
|:---|
| Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) |
| Soliciting material pursuant to Rule 14a-12(b) under the Exchange Act (17 CFR 240.14a-12) |
| Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) |
| Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) |

---

Securities registered pursuant to Section 12(b) of the Act:

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| | | |
|:---|:---|:---|
| &nbsp;&nbsp;**Title of each class** | &nbsp;&nbsp;**Trading Symbol(s)** | &nbsp;&nbsp;**Name of each exchange on<br> which registered** |
| &nbsp;&nbsp;Common stock, par value $0.001 per share | &nbsp;&nbsp;TOVX | &nbsp;&nbsp;NYSE American |

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Indicate by check mark whether the registrant is an emerging growth company as defined in in Rule 405 of the Securities Act of 1933 (17 CFR §230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2 of this chapter).

Emerging growth company ◻

If an emerging growth company, indicate by checkmark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ◻

**Item 8.01. Other Events.**

On October 20, 2025, expanded metastatic pancreatic ductal adenocarcinoma (mPDAC) data from Theriva Biologics, Inc.'s VIRAGE Phase 2b trial (NCT05673811) was presented at a mini oral session at the European Society for Medical Oncology (ESMO 2025) Annual Congress

The ESMO presentation is atatched as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference

**Item 9.01. Financial Statements and Exhibits.**

(d) Exhibits.

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| | |
|:---|:---|
| **Exhibit<br> Number** | **Description** |
| [99.1](tm2529071d1_ex99-1.htm) | [ESMO presentation](tm2529071d1_ex99-1.htm) |
| 104 | Cover Page Interactive Data File (embedded within the XBRL document) |

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**SIGNATURES**

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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| | | | |
|:---|:---|:---|:---|
| Dated: October 20, 2025 | **THERIVA BIOLOGICS, INC.** | **THERIVA BIOLOGICS, INC.** | **THERIVA BIOLOGICS, INC.** |
|  | By: | /s/ Steven A. Shallcross | /s/ Steven A. Shallcross |
|  |  | Name: | Steven A. Shallcross |
|  |  | Title: | Chief Executive Officer and Chief Financial Officer |

---

## Exhibit 99.1

**Exhibit 99.1**

![](tm2529071d1_ex99-1img001.jpg)

Content of this presentation is copyright and responsibility of the author. Permission is required for re - use. R.Garcia - Carbonero VIRAGE trial: randomized Phase IIb, open - label, study of Nab - Paclitaxel and Gemcitabine with/without intravenous VCN - 01 in Patients with Metastatic Pancreatic Cancer (mPDAC) Rocio Garcia - Carbonero \* , Roberto Pazo Cid, Teresa Macarulla, Berta Laquente , Alana Nguyen, Carmen Guillén, Andrés Muñoz, Edward J Kim, Mireya Cazorla, Tara Seery, Miriam Lobo de Mena, Chris Nevala - Plagemann, Vivek Sharma, Eva Martínez de Castro, Charles Le, Mike Kaleko, Mary Ann Shallcross, Carmen Blasco, Manel Cascallo, Manuel Hidalgo . \*Hospital Universitario 12 de Octubre, Universidad Complutense de Madrid, Spain

![](tm2529071d1_ex99-1img002.jpg)

Content of this presentation is copyright and responsibility of the author. Permission is required for re - use. Declaration of Interests R. Garcia - Carbonero Rocio Garcia - Carbonero □ Consultant or Advisory Role: AAA/Novartis, Advanz Pharma, Astellas, Bayer, BMS, Boerhinger , Crinetics , Esteve, GSK, Hutchmed , Ipsen, ITM, MSD, Novocure , PharmaMar, Pierre Fabre, Sanofi, Servier, Takeda □ Research Funding: MSD □ Scientific Societies: Chair of ENETS, ESMO Faculty Coordinator for NETs

![](tm2529071d1_ex99-1img003.jpg)

Content of this presentation is copyright and responsibility of the author. Permission is required for re - use. Background: VCN - 01 R. Garcia - Carbonero VCN - 01 (zabilugene almadenorepvec) is an oncolytic adenovirus designed to replicate in cancer cells with a dysfunctional RB 1 pathway and express hyaluronidase (PH 20) to degrade tumor stroma and facilitate chemotherapy penetrance and antitumor immune response . VCN - 01 nab - paclitaxel gemcitabine T - Cells Neoantigen Cancer Associated Fibroblast Stroma STROMA degradation by PH20 facilitates solid tumor access of VCN - 01 and coadministered cancer therapies SELECTIVE replication at very high levels lyses tumor cells directly without harming healthy tissues IMMUNOGENIC actions of VCN - 01 turn "cold" tumors "hot" and elicit an anti - tumor immune response SYSTEMIC administration delivers VCN - 01 to primary tumor and metastases and detargets the liver Acceptable safety profile and encouraging activity when combined with gemcitabine/nab - paclitaxel in a Phase 1 study (Garcia - Carbonero et al . J Immunother Cancer 10 : e 003255 , 2022) .

![](tm2529071d1_ex99-1img004.jpg)

Content of this presentation is copyright and responsibility of the author. Permission is required for re - use. VIRAGE - Design R. Garcia - Carbonero • VIRAGE is a multicenter, open - label, randomized trial for direct comparison of up to 2 doses of VCN - 01 with gem/nab - paclitaxel (SoC) to SoC alone in patients with metastatic pancreatic adenocarcinoma (mPDAC) • 92 patients to be enrolled with 57 total deaths required for analysis of OS with 80% power to detect a hazard ratio (HR) of 0.51 - 0.65 for OS with 2 - sided alpha 0.1. P - values are displayed as 2 - sided statistical analysis using the log - rank test. ARM 1 IV gemcitabine (125 mg/m 2) IV nab - paclitaxel (1000 mg/m 2) D1, D8 & D15 of each 28 days cycle (SoC) ARM 2 2 doses of IV VCN - 01 (1 x 10 13 vp) one week before : • cycle 1 of SoC • cycle 4 of SoC ▪ Patients with histologically or cytologically confirmed newly - diagnosed mPDAC ▪ No prior systemic therapy ▪ ECOG: 0 - 1 ▪ Stratification factors: x Geographical area (USA vs EU) x ECOG (0 vs 1) R 1:1 n=46 n=46 Primary Objectives x Overall Survival (OS). x Safety and tolerability Secondary x PFS / TTP x ORR x DCR x 1 - year OS and PFS rates x Duration of Response (DoR). x Changes in CA 19.9 Treatment until disease progression, unacceptable toxicity or consent withdrawal

![](tm2529071d1_ex99-1img005.jpg)

Content of this presentation is copyright and responsibility of the author. Permission is required for re - use. VIRAGE - CONSORT R. Garcia - Carbonero Groups for analysis: x Modified Intent - to - Treat (mITT) / Safety population All randomized patients who received any dose of the assigned treatment, including ARM II patients who received VCN - 01 but not SoC x Full Analysis Set (FAS) – evaluating the VCN - 01 + SoC combination: All randomized patients who received one dose of SoC (ARM I) or a complete dose of VCN - 01 and at least one dose of SoC (ARM II). ARM II patients who received VCN - 01 but not SoC were replaced per protocol x Preplanned Subgroup Analysis Set – evaluating potential effects of second VCN - 01 dose All patients who started the 4th cycle of SoC (ARM I) or all patients who received a second dose of VCN - 01 and started the 4th cycle of SoC (ARM II)

![](tm2529071d1_ex99-1img006.jpg)

Content of this presentation is copyright and responsibility of the author. Permission is required for re - use. VIRAGE - Demographics R. Garcia - Carbonero FAS mITT VCN - 01 + SoC (n=48) SoC (n=48) VCN - 01 + SoC (n=53) SoC (n=48) 48 48 53 48 n 66.0 (41 - 86) 68.5 (52 - 85) 66.0 (41 - 86) 68.5 (52 - 85) Median Age in years (range) 18 (37.5) 10 (20.8) 21 (39.6) 10 (20.8) n (%) <65 years 30 (62.5) 38 (79.2) 32 (60.4) 38 (79.2) n (%) ≥65 years 23 (47.9) 22 (45.8) 26 (49.1) 22 (45.8) n (%) Male Gender 25 (52.1) 26 (54.2) 27 (50.9) 26 (54.2) n (%) Female 23.70 25.65 23.70 25.65 Median Body Mass Index (kg/m 2) 19 (39.6) 17 (35.4) 21 (39.6) 17 (35.4) n (%) 0 ECOG at randomization 29 (60.4) 31 (64.6) 32 (60.4) 31 (64.6) n (%) 1 31 (64.6) 40 (83.3) 31 (58.5) 40 (83.3) Yes Liver metastases at baseline 17 (35.4) 8 (16.7) 22 (41.5) 8 (16.7) No 37 (77.1) 38 (79.2) 41 (77.4) 38 (79.2) 1 or 2 Number of metastatic sites 11 (22.9) 10 (20.8) 12 (22.6) 10 (20.8) ≥3 18 (37.5) 20 (41.7) 19 (35.4) 20 (41.7) Head Primary tumor location 30 (62.5) 28 (58.3) 34 (64.4) 28 (58.3) Body and tail 39 (81.2) 40 (83.3) 41 (77.4) 40 (83.3) > 37 UI/ml Ca 19,9 at baseline 9 (18.8) 8 (16.7) 12 (22.6) 8 (16.7) ≤ 37 UI/ml

![](tm2529071d1_ex99-1img007.jpg)

Content of this presentation is copyright and responsibility of the author. Permission is required for re - use. Safety : Treatment Emergent AEs (≥10% patients) R. Garcia - Carbonero VCN - 01 + SoC (N=53) n(%) SoC (N=48) n (%) Preferred Term SOC % Grade≥3 (n) % All grades (n) % Grade ≥3 (n) % All grades (n) 11,3% 6 52,8% 28 14,6% 7 47,9% 23 Anaemia Blood and lymphatic system disorders 33,9% 18 50,9% 27 14,6% 7 37,5% 18 Neutropenia 5,7% 3 43,4% 23 6,3% 3 35,4% 17 Thrombocytopenia 3,8% 2 49,1% 26 2,1% 1 27,1% 13 Abdominal pain Gastrointestinal disorders 34,0% 18 27,1% 13 Constipation 3,8% 2 52,9% 27 6,3% 3 45,9% 22 Diarrhoea 3,8% 2 60,4% 32 27,1% 13 Nausea 1,9% 1 43,4% 24 2,1% 1 20,9% 10 Vomiting 15,1% 8 90,6% 48 14,6% 7 75,0% 36 Asthenia/ Fatigue General disorders and administration site conditions 22,6% 12 2,1% 1 Chills 13,2% 7 17,0% 9 2,1% 1 Influenza like illness 43,4% 23 31,3% 15 Oedema 3,8% 2 77,4% 41 25,0% 12 Pyrexia 20,8% 11 50,9% 27 10,4% 5 20,8% 10 Transaminases increased Investigations 1,9% 1 11,3% 7 4,2% 2 PA increased 7,5% 4 15,0% 8 2,1% 1 GGT increased 1 49,1% 27 2,1% 1 41,7% 20 Decreased appetite Metabolism and nutrition disorders 13,2% 7 6,3% 3 Hypomagnesaemia 3,8% 2 2,1% 1 10,4% 5 Hyponatraemia 13,2% 7 6,3% 3 Arthralgia Musculoskeletal and connective tissue disorders 7,5% 4 12,5% 6 Back pain 13,2% 7 2,1% 1 Musculoskeletal pain 15,1% 8 2,1% 1 Myalgia 26,4% 14 18,8% 9 Dysgeusia Nervous system disorders 9,4% 5 10,4% 5 Headache 9,4% 5 58,5% 31 4,2% 2 43,8% 21 Neurotoxicity 3,8% 2 11,3% 6 6,3% 3 Insomnia Psychiatric disorders 1,9% 1 11,3% 6 4,2% 2 Cough Respiratory, thoracic and mediastinal disorders 11,3% 6 6,3% 3 Dyspnoea 11,3% 6 8,3% 4 Epistaxis 30,2% 16 50,0% 14 Alopecia Skin and subcutaneous tissue disorders 15,1% 8 2,1% 1 Rash 1,9% 1 11,3% 7 2,1% 1 Hypotension Vascular disorders Two TEAE lead to death (1 in each Arm), but none of them were related to VCN - 01 or SoC

![](tm2529071d1_ex99-1img008.jpg)

Content of this presentation is copyright and responsibility of the author. Permission is required for re - use. Safety : VCN - 01 - related TEAEs (≥5% patients) R. Garcia - Carbonero VCN - 01 Dose 2 (N=36) VCN - 01 Dose 1 (N=53) Preferred Term % Grade ≥3 (n) % All grades (n) % Grade ≥3 (n) % All grades (n) - - 52.7% 19 1.9% 1 58.5% 31 Pyrexia 2.8% 1 11.1% 4 1.9% 1 32.1% 17 Asthenia / Fatigue - - 11.1% 4 15.1% 8 30.2% 16 Transaminases increased - - 16.6% 6 - - 30.2% 16 Nausea - - 25.0% 9 - - 26.4% 14 Vomiting - - 2.7% 1 13.2% 7 16.9% 9 Influenza like illness - - 2.7% 1 1.9% 1 13.2% 7 Platelet count decreased/Thrombocytopenia - - 2.7% 1 - - 13.2% 7 Decreased appetite - - 5.5% 3 - - 13.2% 7 Diarrhea - - 19.4% 7 - - 9.4% 5 Chills - - 2.7% 1 5.7% 3 7.5% 4 Lymphocyte count decreased - - - - 5.7% 3 5.7% 4 Gamma - glutamyl transferase increased - - - - 1.9% 1 5.7% 3 Anemia - - 5.5% 2 - - 5.7% 3 Cytokine release syndrome - - - - 3.8% 2 3.8% 2 Treatment - induced liver injury

![](tm2529071d1_ex99-1img009.jpg)

Content of this presentation is copyright and responsibility of the author. Permission is required for re - use. Duration of Response (DoR) SoC VCN - 01 + SoC Response Rate, DoR & PFS R. Garcia - Carbonero DCR % ORR (n) PD SD PR CR 34 (70.8%) 15 (31.3%) 14 19 15 0 SoC (n=48) 37 (77.1%) 19 (39.6%) 11 18 18 1 VCN - 01 (n=48) 0.512 0.314 p - value HR (95% CI) Median (95% CI) Events / Total Treatment Arm Ref. 5.4 (2.0 - 6.8) 11 / 15 SoC 0.22 (0.08 - 0.62) 11.2 (7.4 - NE) 7 / 19 VCN - 01 + SoC Logrank P - value: 0.0035 Progression Free Survival (PFS) Response Rate (ORR) VCN - 01+SoC (n=48) SoC (n=48) VCN - 01+SoC (n=53) SoC (n=48) 7.0 (4.8 - 11.2) 4.6 (3.5 - 6.5) 5.6 (3.8 - 10.4) 4.6 (3.5 - 6.5) Median (95% CI) months 0.55 (0.34 - 0.88) Ref. 0.63 (0.4 - 1.0) Ref. HR (95% CI) 0.012 0.048 (Cox) p - value 0.011 0.047 (Log - rank) Based on CT scan evaluation by sites; + Censor mITT SoC VCN - 01 + SoC FAS SoC VCN - 01 + SoC mITT FAS

![](tm2529071d1_ex99-1img010.jpg)

Content of this presentation is copyright and responsibility of the author. Permission is required for re - use. SoC VCN - 01 + SoC SoC VCN - 01 + SoC Primary Endpoint – Overall Survival R. Garcia - Carbonero VCN - 01+SoC (n=48) SoC (n=48) 10.8 (7.4 - 15.8) 8.6 (6.9 - 11.6) Median (95% CI) months 0.57 (0.34 - 0.96) Ref. HR (95% CI) 0.034 (Cox) p - value 0.055 (Log - rank) + Censor VCN - 01+SoC (n=53) SoC (n=48) 10.6 (6.6 - 14.8) 8.6 (6.9 - 11.6) Median (95% CI) months 0.69 (0.42 - 1.12) Ref. HR (95% CI) 0.136 (Cox) p - value 0.196 (Log - rank) + Censor mITT FAS The prespecified OS primary study endpoint was met

![](tm2529071d1_ex99-1img011.jpg)

Content of this presentation is copyright and responsibility of the author. Permission is required for re - use. Preplanned Subgroup Analysis All patients who started the 4th cycle of SoC (+ 2 doses of VCN - 01 in Arm II) R. Garcia - Carbonero VCN - 01+SoC (n=34) SoC (n=29) VCN - 01+SoC (n=34) SoC (n=29) 14.8 (10.6 - NE) 11.6 (8.6 - 12.8) 11.2 (7.3 - 16.6) 7.4 (5.7 - 8.4) Median (95% CI) months 0.44 (0.21 - 0.92) Ref. 0.48 (0.25 - 0.91) Ref. HR (95% CI) 0.029 0.025 (Cox) p - value 0.046 0.017 (Log - rank) Based on CT scan evaluation by sites; + Censor PFS OS C5+ 4 Cycle 3 Cycle 2 Cycle 1 Cycle TREATMENT ARM I: SoC ARM II: SoC+VCN - 01 \| 120 \| 113 \| 106 \| 99 \| 92 \| 85 \| 78 \| 71 \| 64 \| 57 \| 50 \| 43 \| 36 \| 29 \| 22 \| 15 \| 8 \| 1 Day SoC VCN - 01 + SoC OS SoC VCN - 01 + SoC PFS Arm I Arm II

![](tm2529071d1_ex99-1img012.jpg)

Content of this presentation is copyright and responsibility of the author. Permission is required for re - use. Results – Biologic Data R. Garcia - Carbonero 0 100 200 300 400 500 600 160 640 2,560 10,240 40,960 163,840 Days (since 1st VCN-01 dose) N a b T i t e r (1 / x) VCN - 01 genomes in patients blood NAbs titers in patients sera\* \*NAb's titers: levels of neutralizing antibodies against VCN - 01 Sustained VCN - 01 genomes levels indicated persistent replication and confirmed the bioactivity of the 2 nd dose despite the presence of neutralizing antibodies (NAbs)

![](tm2529071d1_ex99-1img013.jpg)

Content of this presentation is copyright and responsibility of the author. Permission is required for re - use. Conclusions R. Garcia - Carbonero • VCN - 01 at 1E13 vp /dose combined with gemcitabine/nab - paclitaxel was safe and well tolerated • VCN - 01 - related serious adverse events were transient and resolved, the most common being flu - like symptoms, transaminase increase and drug - induced liver injury. • VCN - 01 significantly improved OS (primary endpoint) in combination with Gem - Abraxane as compared to Gem - Abraxane alone in patients with chemonaïve metastatic pancreatic adenocarcinoma. • Survival benefit was greater among pts who received 2 VCN - 01 doses and with longer follow - up • PFS was also significantly improved with the addition of VCN - 01 to SoC. • ORR was numerically higher among pts treated with VCN - 01 and chemotherapy, and the duration of response was doubled as compared to patients treated only with chemotherapy. • These encouraging data support further evaluation of this combination in a larger, blinded clinical trial with additional VCN - 01 doses

![](tm2529071d1_ex99-1img014.jpg)

Content of this presentation is copyright and responsibility of the author. Permission is required for re - use. Thank you!!! We want to thank all patients, their families, investigators and their study team who participated in VIRAGE trial. R.Garcia - Carbonero

![](tm2529071d1_ex99-1img015.jpg)

European Society for Medical Oncology (ESMO) Via Ginevra 4, CH - 6900 Lugano T. +41 (0)91 973 19 00 esmo@esmo.org esmo.org