Full Press Release Details
Purple Biotech Announces Publication in Nature
Cancer Demonstrating Mechanisms Behind Cancer Cell Persistence Frequency and Potential of NT219 to Reduce Therapeutic Resistance
Research Highlights Underlying the IRS1 Phosphorylation
Status as a Memory Mechanism that Modulates Cellular Non-Genetic Resistance to Drug Therapy
NT219, which Targets IRS, Shown to be Highly
Synergistic with anti-EGFR Therapy, Leading to Tumor Regression and Delayed Recurrence
Israel, October 22, 2021 (GLOBE NEWSWIRE) -- Purple Biotech (NASDAQ/TASE: PPBT), a clinical-stage company developing first-in-class, effective
and durable therapies by overcoming tumor immune evasion and drug resistance, today announced a publication in Nature Cancer that
provides new insight into the underlying mechanism of the therapeutic resistance of cancer cells and the significant role of insulin receptor
substrate 1 (IRS1) pathway on epithelial growth factor receptor (EFGR) inhibition therapy. NT219, currently being evaluated in a Phase
1/2 clinical trial, is a novel small molecule inhibiting simultaneously IRS1/2 and STAT3.
is titled, "IRS1 phosphorylation underlies the non-stochastic probability of cancer cells to persist during EGFR inhibition therapy,"
and is available online at: https://www.nature.com/articles/s43018-021-00261-1. The lead
author of the publication is Ravid Straussman, M.D., Ph.D., Department of Molecular Cell Biology, Weizmann Institute of Science,
demonstrated mechanistic evidence of cancer cells' inherited therapeutic resistance, termed chance to persist (CTP). It was shown in preclinical
models, that the CTP EGFR inhibition is modulated by serine/threonine phosphorylation of the IRS1. Specifically, it has been shown that
higher phosphorylation of IRS1 multiple serine/threonine sites, which blocks IRS1 activity, results in increased susceptibility to EGFR
inhibitors. A combination of NT219, which triggers serine phosphorylation and subsequent degradation of IRS1 and EGFR inhibitors, resulted
in a synergistic effect, leading to tumor regression and delayed recurrence upon treatment withdrawal.
results provide new insight into cellular persistence regulation and further advance the understanding of IRS1 inhibition in the cancer
phenotype, as well as highlight the potential of NT219 to ameliorate tumor cell resistance to apoptosis," said Hadas Reuveni, Ph.D.,
VP Research and Development of Purple Biotech. "The results strengthen our previously published data on synergistic effects with
certain anti-cancer agents, and further support our clinical development strategy of combining NT219 with anti-EGFR inhibitors."
Biotech Ltd. is a clinical-stage company developing first-in-class therapies by overcoming tumor immune evasion and drug resistance.
The Company's oncology pipeline includes NT219 and CM24. NT219 is a dual inhibitor, a novel small molecule that simultaneously
targets IRS1/2 and STAT3. The Company is currently advancing NT219 as monotherapy treatment of solid tumors, followed by a dose
escalation of NT219 in combination with cetuximab for the treatment of recurrent and/or metastatic squamous cell carcinoma of the
head and neck cancer (SCCHN) or colorectal adenocarcinoma in a phase 1/2 study, and an expansion phase of NT219 at its recommended
phase 2 level in combination with cetuximab in patients with recurrent and/or metastatic squamous cell carcinoma of the head and
neck. 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 selected cancer indications in a phase 1b study followed by a phase 2 for the treatment of non-small cell lung cancer
and pancreatic cancer. The Company has entered into a clinical collaboration agreement, as amended, with Bristol Myers Squibb for
the planned phase 1/2 clinical trials to evaluate the combination of CM24 with the PD-1 inhibitor nivolumab (Opdivo ) in
patients with non-small cell lung cancer and in combination with nivolumab in addition to nab-paclitaxel (Abraxane ) in patients
with pancreatic cancer. The Company's corporate headquarters are located in Rehovot, Israel. For more information, please visit
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current views, expectations, beliefs or intentions with respect to future events, and are subject to a number of assumptions,
involve known and unknown risks, many of which are beyond our control, as well as uncertainties and other factors that may cause our
actual results, performance or achievements to be significantly different from any future results, performance or achievements
expressed or implied by the forward-looking statements. Important factors that could cause or contribute to such differences
include, among others, risks relating to: the plans, strategies and objectives of management for future operations; product
development for NT219 and CM24; the process by which early stage therapeutic candidates such as NT219 and CM24 could potentially
lead to an approved drug product is long and subject to highly significant risks, particularly with respect to a joint development
collaboration; the fact that drug development and commercialization involves a lengthy and expensive process with uncertain
outcomes; our ability to successfully develop and commercialize our pharmaceutical products; the expense, length, progress and
results of any clinical trials; the impact of any changes in regulation and legislation that could affect the pharmaceutical
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are discussed in our Annual Report on Form 20-F for the year ended December 31, 2020 and in our other filings with the U.S.
Securities and Exchange Commission ("SEC"), including our cautionary discussion of risks and uncertainties under
"Risk Factors" in our Registration Statements and Annual Reports. These are factors that we believe could cause our actual
results to differ materially from expected results. Other factors besides those we have listed could also adversely affect
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& Chief Financial Officer