Purple Biotech Achieves Manufacturing Milestone for IM1240, a Tri-Specific Antibody from the CAPTN-3 Platform

Achieved commercially viable yield for IM1240, positioning the program competitively for future development

Validates scalability of the CAPTN-3 tri-specific antibody platform

IM1240, the first CAPTN-3 tri-specific antibody targeting the novel tumor-associated antigen 5T4, advances toward first-in-human clinical trials, with an Investigational New Drug (IND) submission planned for 2026

REHOVOT, Israel, Oct. 29, 2025 (GLOBE NEWSWIRE) -- Purple Biotech Ltd. (“Purple Biotech” or the “Company”) (NASDAQ/TASE: PPBT), a clinical-stage company developing first-in-class therapies that seek to overcome tumor immune evasion and drug resistance, today announced the achievement of a manufacturing milestone for IM1240, a tri-specific antibody from the CAPTN-3 platform, which targets the tumor-associated antigen 5T4, the activating receptor CD3 on T cells and the inhibitory receptor NKG2A on NK and CD8⁺ T cells.

“Establishing a process capable of producing tri-specific antibodies marks a major step in our development program,” said Gil Efron, CEO of Purple Biotech. “We have developed a high-efficiency manufacturing and purification process that is designed to deliver a differentiated T cell engager with a capped, cleavable polypeptide designed to help prevent off-tumor immune activation. This milestone positions our CAPTN-3 platform as an attractive potential solution for developing complex tri-specific antibodies with both competitive yield and purity.”

“Drawing on my decades of experience in antibody manufacturing, producing a tri-specific protein such as IM1240 at high yield and purity was perceived as a significant challenge-one that I’m pleased to have successfully mastered,” added Dr. Michael Schickler, Head of Clinical and Regulatory Affairs of Purple Biotech. “Our technology is designed to deliver a triple mechanism of action: it activates NK cells and highly cytotoxic T cells by blocking the inhibitory NKG2A–HLA-E interaction and engages cytotoxic T cells through CD3 targeting driving a potent anti-tumor immune response. The antibody’s structure incorporates a protease-cleavable albumin-bound cap that prevents systemic CD3 immune activation. By limiting immune activation to the tumor microenvironment, this approach is designed to offer a potentially safer therapeutic profile and an extended half-life.”

The CAPTN-3 platform generates conditionally activated tri-specific antibodies, which engage both T cells and NK cells to induce a strong, localized immune response within the tumor microenvironment (TME). The cleavable capping technology confines the compound’s therapeutic activity to the local TME, thereby potentially increasing the anticipated therapeutic window in patients. The third arm specifically targets the tumor associated antigen (TAA). This technology presents a novel mechanism of action by unleashing both innate and adaptive immune systems to mount an optimal anti-tumoral immune response.

About Purple Biotech

Purple Biotech Ltd. (NASDAQ/TASE: PPBT) is a clinical-stage company developing first-in-class therapies that seek to overcome tumor immune evasion and drug resistance. The Company’s oncology pipeline includes CAPTN-3, CM24 and NT219. The Company is advancing CAPTN-3, a preclinical platform of conditionally activated tri-specific antibodies, which engage both T cells and NK cells to induce a strong, localized immune response within the tumor microenvironment. The cleavable capping technology confines the compound’s therapeutic activity to the local tumor microenvironment, thereby potentially increasing the anticipated therapeutic window in patients. The third arm specifically targets the Tumor Associated Antigen (TAA). The technology presents a novel mechanism of action by unleashing both innate and adaptive immune systems to mount an optimal anti-tumoral immune response. IM1240 is the first tri-specific antibody in development that targets the 5T4 antigen, which is expressed in a variety of solid tumors and is associated with advanced disease, increased invasiveness, and poor clinical outcomes. IM1305 is the second tri-specific antibody from the platform in development and targets the TROP2 TAA. CM24 is a humanized monoclonal antibody that blocks CEACAM1, which supports tumor immune evasion and survival through multiple pathways. CEACAM1 on tumor cells, immune cells and neutrophil extracellular traps is a novel target for the treatment of multiple cancer indications. As proof of concept of these novel pathways, the Company completed a Phase 2 study for the treatment of pancreatic ductal adenocarcinoma (PDAC) with CM24 as a combination therapy with the anti-PD-1 checkpoint inhibitor nivolumab and chemotherapy, demonstrating clear and consistent improvement across all efficacy endpoints and the identification of two potential serum biomarkers and other potential tissue biomarkers. NT219 is a dual inhibitor, novel small molecule that simultaneously targets IRS1/2 and STAT3. A Phase 1 dose escalation study was concluded as a monotherapy and in combination with cetuximab, in which NT219 demonstrated anti-tumor activity in combination with cetuximab in second-line patients with recurrent and/or metastatic squamous cell carcinoma of the head and neck (R/M SCCHN). A Phase 2 study in collaboration with the University of Colorado, to treat R/M SCCHN patients with NT219 in combination with cetuximab or pembrolizumab was initiated. The Company’s corporate headquarters are located in Rehovot, Israel. For more information, please visit https://purple-biotech.com /.

Forward-Looking Statements and Safe Harbor Statement

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CONTACTS:

Company Contact: [email protected]