Calidi Biotherapeutics Advances CLD-401 Oncolytic Virus Therapy Toward IND Filing in Q4 2026
Key Insights
Calidi Biotherapeutics (search) plans to file an IND application in Q4 2026 for CLD-401 (search), a systemically delivered oncolytic virus engineered to deliver IL-15 superagonist (search) to metastatic tumor sites.
The company's RedTail platform demonstrated in preclinical studies that it can avoid immune clearance through CD55 (search) expression and specifically replicate in tumor cells while delivering therapeutic payloads.
Phase I trials will target a basket of solid tumors including non-small cell lung cancer (search), triple-negative breast cancer (search), and head and neck cancer (search) with streamlined dose escalation.
Calidi Biotherapeutics (search) announced plans to file an Investigational New Drug (IND) application in Q4 2026 for CLD-401 (search), its lead candidate from the proprietary RedTail platform designed to systemically deliver targeted genetic medicines to metastatic tumor sites. The tumor-tropic oncolytic virus represents a novel approach to overcoming the accessibility limitations of traditional cancer therapies.
RedTail Platform Demonstrates Immune Evasion Capabilities
The company's RedTail platform has shown promising preclinical results in addressing key challenges facing oncolytic virus therapies. According to CEO Eric Poma, PhD, "We demonstrated that in clinically relevant immunocompetent murine models and ex vivo human immune assays, our RedTail platform has been engineered to prevent immune clearance after systemic administration and to only replicate in tumor cells with high specificity."
Data presented at the American Society for Clinical Oncology (ASCO) in May 2025 demonstrated that CLD-401 (search)'s engineered expression of CD55 (search) on the enveloped virus allows it to avoid immune clearance and enables systemic administration. The CD55-expressing enveloped virus specifically targets metastatic disease (search) patients with high unmet medical need.
Further validation came from data presented at the Society of Immunotherapy for Cancer (SITC) in November 2025, showing that in syngeneic murine models, the RedTail platform remains protected from immune clearance after systemic administration and can specifically replicate in tumor cells at metastatic sites.
CLD-401 Mechanism and Clinical Development Strategy
CLD-401 (search) is engineered as a tumor-tropic oncolytic virus designed to home to metastatic sites after systemic administration, replicate only in tumor cells, induce an immune priming event at the tumor site, and express high levels of IL-15 superagonist (search) in the tumor microenvironment (TME). IL-15 superagonist is a potent cytokine that induces natural killer (NK) and T-cell responses to tumors.
The planned Phase I study will be conducted as a basket trial in solid tumors, including non-small cell lung cancer (search), triple-negative breast cancer (search), and head and neck cancer (search). The company anticipates a streamlined dose escalation study with a limited number of doses to be tested, with the initial dose cohort expected to be in the therapeutic range, potentially enabling proof-of-concept data early in Phase I.
Platform Versatility and Future Applications
Beyond CLD-401 (search), Calidi expects to present proof-of-concept data demonstrating the RedTail platform's versatility in delivering tumor-localized bi-specific T cell engagers (BiTEs) alongside T-cell amplifiers. This approach addresses a significant limitation of BiTEs in solid tumors, which have struggled to drive efficacy due to a lack of activated T-cells in the tumor microenvironment. The RedTail platform's ability to simultaneously deliver high expression of multiple payloads into the TME may overcome these previous limitations.
The company is also exploring applications beyond oncology, investigating new payloads for inflammatory and immune diseases. Future developments include targeting other cell types through envelope engineering, such as CD38 (search) and BCMA (search), and leveraging selective viral replication in proliferative cells like activated B cells.
Leadership and Financial Position
Calidi strengthened its management team in 2025 with the appointment of Eric Poma, PhD, as CEO, bringing over 25 years of biopharmaceutical industry experience, and Guy Travis Clifton, MD, as Chief Medical Officer. Dr. Clifton is a practicing surgical oncologist with over 17 years of experience in drug development and cancer immunotherapy.
The company also reconstituted its Scientific Advisory Board with notable additions including Mace L. Rothenberg, MD, FACP, former Chief Medical Officer of Pfizer, and John Wrangle, MD, MPH, a thoracic oncologist with extensive experience in IL-15-based treatment for metastatic cancer.
Financially, Calidi reduced its debt burden by $3.1 million in 2025, decreasing term debt and notes payable from $3.8 million at December 31, 2024, to $0.7 million at December 31, 2025. The company also reduced general and administrative expenses by $2.3 million in the first nine months of 2025 compared to the same period in 2024.