Purple Biotech Presents Phase 1 Interim Monotherapy Data for NT219 Demonstrating Encouraging Safety & Efficacy Profile

Purple Biotech Ltd. recently announced positive interim safety and efficacy data from the Phase 1 study of NT219 in adults with advanced solid tumors. Findings were presented during the 2022 American Society of Clinical Oncology (ASCO) Annual Meeting as a poster presentation during the Developmental Therapeutics—Molecularly Targeted Agents and Tumor Biology track (Abstract #3096).

“We are very encouraged by the initial safety and efficacy signals from NT219, and the durability of response,” said Michael Schickler, PhD, Head of Clinical & Regularly Affairs at Purple Biotech. “One patient with refractory gastroesophageal junction cancer, previously treated with four prior lines of therapies, was treated for 22 weeks and achieved a confirmed partial response. Remarkably, the patient has not progressed, approximately 1 year after the end of treatment. This, together with the demonstrated stable disease for patients with mutated-KRAS colon cancer and with the preclinical studies of NT219 in this cancer type, support the continuation of future clinical studies with NT219.”

As of May 12, 2022, a total of 14 patients were enrolled to four NT219 dose levels (3 – 24mg/kg) in the dose escalation phase, of which 12 were evaluable for dose limiting toxicity (DLT) determination. Four patients included with colorectal cancer (CRC), three with pancreatic cancer, two with breast cancer, and one of each of the following cancers: gastroesophageal junction (GEJ), esophageal and appendiceal cancer. The median number of prior treatment regimens for metastatic disease was 4 (median 2-11). Eight Grade 3 adverse events (AEs) were observed, no Grade 4 AEs or treatment related deaths were reported.

For the 12 evaluable patients, best overall response included one confirmed partial response (GEJ patient > 5.5 months duration of response), 3 stable disease (SD), in CRC patients with mutated KRAS, and one patient awaiting follow up MRI/CT scans.  As of the cutoff date, ten patients that completed the dose limiting toxicity (DLT) period were either on treatment or in follow up (range 1.1 to 18 months). Evaluation of NT219 safety monotherapy and in combination with cetuximab continues in additional patients with advanced cancers.

“These data demonstrate the strong potential of NT219 as a viable treatment option for patients with cancer,” said Isaac Israel, CEO of Purple Biotech. “As we continue to advance our portfolio of assets, we are focused on bringing forward a human-centric approach to cancer treatment, exploring agents and mechanisms of action that others may have overlooked, in order to improve patient outcomes. Our goal is to study NT219 in combination with cetuximab in patients with recurrent and metastatic colorectal cancer and squamous cell carcinoma of the head and neck (SCCHN), which we have already started.”

NT219 is a first-in-class small molecule, a direct inhibitor of Insulin Receptor Substrates 1/2 (IRS) and STAT3, targeting IRS for degradation and suppressing STAT3 phosphorylation. Both IRS1/2 and STAT3 are major signaling junctions regulated by various oncogenes, mediating mitogenic, anti-angiogenic and metastatic processes and play an important role in the modulation of both the tumor and the tumor microenvironment, affecting drug resistance and duration of response.

Purple Biotech Ltd. is a clinical-stage company developing first-in-class therapies designed to overcome tumor immune evasion and drug resistance. The company’s oncology pipeline includes NT219 and CM24. NT219 is a dual inhibitor, novel small molecule that simultaneously targets IRS1/2 and STAT3. The Company is currently advancing NT219 as a 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 dose in combination with cetuximab in patients with recurrent and/or 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 selected cancer indications. The company initiated a Phase 2 study for the treatment of pancreatic ductal adenocarcinoma (PDAC). The company has entered into a clinical collaboration agreement, as amended, with Bristol Myers Squibb for the phase 1/2 clinical trials, to evaluate the combination of CM24 with the PD-1 inhibitor nivolumab (Opdivo) in addition to chemotherapy. The company’s corporate headquarters are located in Rehovot, Israel. For more information, visit https://purple-biotech.com.