Purple Biotech Reports Positive Results of CM24 Dose Escalation in Advanced Pancreatic Cancer Patients

Purple Biotech Ltd. recently announced the completion and data maturity of its Phase 1 dose escalation study of CM24, a first-in-class anti-CEACAM1 monoclonal antibody addressing multiple tumor types.

In the dose escalation part of the study, 11 refractory, pancreatic ductal adenocarcinoma (PDAC) patients whose cancer progressed following two lines of prior therapies were treated with CM24 at 10, 15 and 20mg/kg once every 2 weeks (q2w) and nivolumab at 480mg once every four weeks (q4w).

The investigational immunotherapy combination was well tolerated across all dose levels with no recorded Drug Limiting Toxicities (DLTs). Grade 3 adverse events were reported in 6 of the patients and none was considered related to the study drugs. No Grade 4 or deaths were reported.

Overall Survival (OS) data across all dose levels from this study with Purple’s chemo free CM24 in combination with nivolumab, demonstrated comparable OS rate in comparison to historical data of third line patients treated with chemotherapy, which demonstrate an OS median rate in a range of 3 to 4 months.

Among the patients who demonstrated a response or disease control from the CM24 + nivolumab treatment, one third line patient has survived for 14.6 months. The patient had Microsatellite Stable (MSS) and PDL-1 IHC 2+ and 5% staining, features not expected to respond to immuno-oncology therapy.

Based on the study’s safety, tolerability, efficacy, pharmacokinetic and pharmacodynamic data, the recommended Phase 2 dose of CM24 in combination with nivolumab was determined to be 20mg/kg. We believe these encouraging and confirmed final results provide additional support to the rationale for conducting the already initiated Phase 2 randomized study of CM24 in combination with nivolumab and standard of care chemotherapy vs. standard of care chemotherapy alone, in the second line PDAC setting. This randomized Phase 2 study (NCT04731467) is being conducted as part of Purple Biotech’s clinical collaboration with Bristol Myers Squibb.

“We are highly encouraged by these latest Phase 1 data and plan to provide further details from this study at an upcoming medical conference,” said Isaac Israel, Purple Biotech’s Acting Chief Executive Officer. “As we continue the Phase 2, which is enrolling as planned across multiple sites in the U.S., Europe, and Israel, we expect to share initial Phase 2 data by the end of 2023 and topline results later in 2024.”

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 NT219, CM24 and IM1240. NT219 is a dual inhibitor, novel small molecule that simultaneously targets IRS1/2 and STAT3. In a Phase 1/2 study of NT219, the company is currently advancing it in a dose escalation as a monotherapy treatment of solid tumors, and in a dose escalation in combination with cetuximab for the treatment of recurrent and metastatic squamous cell carcinoma of the head and neck (SCCHN) or colorectal adenocarcinoma (CRC). These studies will be followed by an expansion phase of NT219 at its recommended Phase 2 level in combination with cetuximab in patients with recurrent and metastatic SCCHN. CM24 is a humanized monoclonal antibody that blocks CEACAM1, an immune checkpoint protein that supports tumor immune evasion and survival through multiple pathways. The Company is advancing CM24 as a combination therapy with anti-PD-1 checkpoint inhibitors in a Phase 2 study for the treatment of pancreatic ductal adenocarcinoma (PDAC). The Company has entered into a clinical collaboration agreement with Bristol Myers Squibb for the Phase 2 clinical trials to evaluate the combination of CM24 with the PD-1 inhibitor nivolumab in addition to chemotherapy. IM1240 is a preclinical, conditionally-activated tri-specific antibody that engages both T cells and NK cells to mount a strong, localized immune response within the tumor microenvironment. The third arm specifically targets the Tumor Associated Antigen (TAA) 5T4 that is expressed in a variety of solid tumors and is correlated with advanced disease, increased invasiveness and poor clinical outcomes. IM1240 has a cleavable capping technology that confines the compound’s therapeutic activity to the local tumor microenvironment, and thereby potentially increases the anticipated therapeutic window in patients. The Company’s corporate headquarters are located in Rehovot, Israel. For more information, visit https://purple-biotech.com/.