Purple Biotech Stock Price, News & Analysis

Purple Biotech Ltd. (NASDAQ/TASE: PPBT) is a clinical-stage oncology company in the pharmaceutical preparation manufacturing industry. According to company disclosures, Purple Biotech focuses on developing first-in-class therapies that seek to overcome tumor immune evasion and drug resistance. The company’s work centers on solid tumors and treatment-resistant cancers, with a pipeline that includes antibody-based immunotherapies and a small-molecule dual inhibitor. Purple Biotech’s corporate headquarters are located in Rehovot, Israel.

The company’s oncology pipeline includes three main programs: CAPTN-3, CM24 and NT219. CAPTN-3 is described as a preclinical platform of conditionally activated tri-specific antibodies that engage both T cells and natural killer (NK) cells to induce a localized immune response within the tumor microenvironment. CM24 is a humanized monoclonal antibody targeting CEACAM1, and NT219 is a novel small molecule that simultaneously targets IRS1/2 and STAT3. Across these programs, Purple Biotech’s stated aim is to address mechanisms that allow tumors to evade immune attack or develop resistance to existing therapies.

CAPTN-3 tri-specific antibody platform

CAPTN-3 is described in multiple company communications as Purple Biotech’s lead program and a platform of capped tri-specific antibodies. These antibodies are designed to engage T cells, engage NK cells, and bind to a tumor-associated antigen (TAA) through three functional arms. The company states that CAPTN-3 antibodies are conditionally activated: a cleavable capping technology masks the CD3-binding arm in circulation and is intended to confine immune activation to the tumor microenvironment. According to Purple Biotech, this design is intended to expand the therapeutic window compared with conventional T-cell engagers by limiting systemic immune activation.

The platform’s first development candidate is IM1240, described as a tri-specific antibody targeting the 5T4 tumor-associated antigen, CD3 on T cells and NKG2A on NK and CD8⁺ T cells (capped-CD3×5T4×NKG2A). Company reports state that 5T4 is expressed in a variety of solid tumors and is associated with advanced disease, increased invasiveness and poor clinical outcomes. IM1240 is characterized as the first tri-specific antibody in development that targets the 5T4 antigen. Purple Biotech has reported preclinical data showing anti-tumor activity, including in models resistant to prior PD-1 therapy, and has highlighted the contribution of both the CD3 and NKG2A arms to its activity.

A second tri-specific candidate from the platform, IM1305, targets the TROP2 tumor-associated antigen in addition to masked CD3 and NKG2A arms (capped-CD3×TROP2×NKG2A). Company presentations and press releases describe IM1305 as validating the adaptability of the CAPTN-3 platform to different tumor antigens. Preclinical data reported by Purple Biotech indicate high-affinity binding to TROP2 and NKG2A and PBMC-mediated tumor cell killing across multiple tumor types in experimental models.

Purple Biotech has also emphasized the capping and conditional activation design of CAPTN-3. The cleavable, albumin-bound cap on the CD3 arm is intended to prevent off-tumor immune activation by masking CD3 binding in circulation and unmasking it in the tumor microenvironment. The company reports that this structure is designed to deliver a triple mechanism of action: blocking the inhibitory NKG2A–HLA-E interaction to activate NK and CD8⁺ T cells, engaging cytotoxic T cells via CD3, and targeting tumor-associated antigens such as 5T4 or TROP2.

CAPTN-3 development progress

According to company announcements, Purple Biotech has achieved several development milestones for CAPTN-3. For IM1240, the company reports a manufacturing and scalability milestone with a commercially viable yield, describing a process capable of producing a tri-specific antibody at high yield and purity. In non-human primate toxicology studies, Purple Biotech states that IM1240 showed a favorable safety and tolerability profile and that its proprietary capping technology enabled dosing at levels up to 300-fold higher than a non-capped comparator, with reduced immune-related toxicity and minimal cytokine release in that study.

The company has also reported pharmacokinetic data for IM1240 in non-human primates, describing increased systemic exposure, dose-dependent and proportional increases in exposure, and a prolonged circulating half-life attributed to the albumin moiety and capping design. Purple Biotech notes that efficacy observed in tumor-bearing mouse models occurred at exposures lower than those achieved in the toxicology study, which it interprets as supportive of an expanded therapeutic window.

In collaboration with academic researchers, including work at the Icahn School of Medicine at Mount Sinai, Purple Biotech has disclosed ex vivo data using patient-derived tumor biopsies. These reports describe IM1240-induced cancer cell apoptosis in head and neck squamous cell carcinoma (HNSCC) and non-small cell lung cancer (NSCLC) samples that were resistant to anti-PD-1 therapy, with activity dependent on both CD3 and NKG2A arms. Transcriptomic analyses cited by the company indicate that NKG2A expression co-occurs with 5T4 or TROP2 in solid tissues, which the company uses to support the rationale for including an NKG2A arm in CAPTN-3 designs.

CM24: CEACAM1-blocking monoclonal antibody

CM24 is a humanized monoclonal antibody that blocks CEACAM1, a glycoprotein that Purple Biotech describes as playing a role in tumor immune evasion and survival through multiple pathways. The company notes that CEACAM1 is present on tumor cells, immune cells and neutrophil extracellular traps, and presents it as a novel target for multiple cancer indications. As proof of concept, Purple Biotech reports completion of a Phase 2 study in pancreatic ductal adenocarcinoma (PDAC), where CM24 was given in combination with the anti-PD-1 checkpoint inhibitor nivolumab and chemotherapy. In company communications, Purple Biotech states that this study demonstrated clear and consistent improvement across all efficacy endpoints and led to the identification of potential serum and tissue biomarkers for patient selection in future studies.

The company has described plans for a subsequent Phase 2b study design focusing on patient selection based on identified biomarkers and on evaluating CM24 in different combination arms, including CM24 with standard of care and CM24 with anti-PD-1 plus standard of care, compared with standard of care alone. Purple Biotech has indicated that this next study is subject to partnering.

NT219: dual IRS1/2 degrader and STAT3 blocker

NT219 is described by Purple Biotech as a dual inhibitor, novel small molecule that covalently binds to insulin receptor substrates 1 and 2 (IRS1/2), leads to IRS1/2 degradation, and blocks STAT3. Both targets are characterized by the company as key drivers of drug resistance and tumor immune evasion. The company has reported a completed Phase 1 dose escalation study of NT219 as 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).

Purple Biotech has initiated a Phase 2 study in R/M SCCHN in collaboration with the University of Colorado Anschutz Medical Campus, evaluating NT219 in combination with pembrolizumab or cetuximab. The company has also announced an intention to grant a European patent application covering combinations of NT219 with leading immunotherapies (such as anti-PD-1, PD-L1, CTLA-4 and CD20 antibodies), MEK inhibitors and selected chemotherapies or targeted agents, with the aim of addressing cancers that develop resistance driven by KRAS amplification or mutation. The company cites preclinical data showing synergistic activity of NT219 with immunotherapy in suppressing refractory tumors and altering the tumor microenvironment.

Regulatory status and listings

Purple Biotech is identified in its filings as a foreign private issuer reporting on Form 20-F and furnishing current reports on Form 6-K under the Securities Exchange Act of 1934. The company’s securities trade on the Nasdaq Capital Market under the symbol PPBT, and its ordinary shares are also traded on the Tel Aviv Stock Exchange under the same symbol. In October 2025, Purple Biotech reported receiving a Nasdaq notification regarding non-compliance with the minimum bid price requirement. The company stated that this notification had no immediate effect on its Nasdaq listing or trading of its American Depositary Shares and outlined the standard compliance period and potential remedies under Nasdaq rules.

In addition to public offerings of American Depositary Shares and warrants, Purple Biotech has entered into at-the-market (ATM) offering agreements to sell ADSs under shelf registration statements on Form F-3. The company has also filed and maintained multiple registration statements on Forms F-1, F-3 and S-8, as reflected in its Form 6-K incorporation-by-reference disclosures.

Business model and focus

Based on the company’s own descriptions, Purple Biotech’s business model is centered on research and development of oncology therapeutics rather than on commercial product sales. The company reports research and development expenses and general and administrative expenses in its financial statements and characterizes itself as a clinical-stage company. Its value proposition, as described in its press releases and filings, lies in developing therapies that directly address tumor immune evasion and resistance mechanisms, using approaches such as tri-specific antibody platforms, checkpoint blockade via CEACAM1 and NKG2A, and dual modulation of IRS1/2 and STAT3.

The company’s disclosures emphasize collaboration with academic institutions, including the Icahn School of Medicine at Mount Sinai and the University of Colorado Anschutz Medical Campus, for preclinical and clinical work. Purple Biotech also highlights intellectual property developments, such as the European patent intention to grant for NT219 combinations, as part of its strategy to protect its therapeutic candidates and combination approaches.

Geographic and corporate profile

Purple Biotech identifies itself as headquartered in Rehovot, Israel, with principal executive offices located in a science park in that city. As a foreign private issuer, it files reports with the U.S. Securities and Exchange Commission and maintains listings on both Nasdaq and the Tel Aviv Stock Exchange. The company’s disclosures do not provide additional geographic breakdown of operations beyond its Israeli headquarters and collaborations with institutions in other countries.

Investor considerations

Investors researching PPBT stock encounter a company that, according to its own reports, is in the clinical and preclinical development stages across multiple oncology programs. Its pipeline includes antibody-based immunotherapies (CAPTN-3 and CM24) and a small-molecule dual modulator (NT219), all aimed at mechanisms of tumor immune evasion and resistance. Regulatory filings and press releases provide information on clinical trial status, preclinical data, manufacturing milestones, financing transactions, and listing compliance matters.

Because Purple Biotech is a clinical-stage company, its SEC filings and press releases contain forward-looking statements and risk disclosures regarding development timelines, regulatory submissions, clinical outcomes, financing, and listing status. Prospective investors typically review the company’s annual report on Form 20-F, current reports on Form 6-K, and detailed pipeline descriptions to understand the scientific rationale and development stage of each asset.