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Update on pH-sensitive fluorescent nanoprobe from late-breaking oral presentation at The World Molecular Imaging Congress

Pegsitacianine has successfully detected disease in six different tumor types with four different FDA-approved imaging devices

SOUTHLAKE, Texas – October 14, 2021 – OncoNano Medicine, Inc. announced results from  a Phase 2 study of its lead clinical development candidate, pegsitacianine, presented as a late- breaking oral presentation at the 2021 World Molecular Imaging Congress (WMIC). This late- breaking oral presentation by Dr. Jason Newman of the University of Pennsylvania Health System revealed the fluorescent nanoprobe, pegsitacianine, provided real-time surgical imaging in a tumor-agnostic manner for the accurate identification of malignant tissue in the operating room.

Pegsitacianine is an intraoperative fluorescence imaging agent under development by OncoNano Medicine for the detection of cancerous tissue in patients undergoing removal of their solid tumor. Relying on an ultra pH-sensitive activation mechanism of OncoNano’s ON-BOARDTM platform, pegsitacianine exists in a fluorescently dark ( “Off”) state at physiological pH but transitions rapidly to a fluorescently “On” state in the presence of the elevated acidic tumor microenvironment. Pegsitacianine’s unique mechanism of action provides it with the potential to function as a tumor agnostic imaging agent compatible with most clinical cameras designed for ICG imaging across a variety of solid tumor types. Pegsitacianine has previously been studied in a Phase 1 clinical trial where breast, head and neck, colorectal, and esophageal cancers were successfully imaged following an intravenous dose of pegsitacianine.

“The Phase 2 study results for pegsitacianine presented at the recent World Molecular Imaging Congress indicate this fluorescent nanoprobe has the potential to change the current surgical paradigm,” said Dr. Newman. “With the real-time feedback that pegsitacianine provides, we could now have a tool that offers real-time surgical imaging on margin status and provides a greater degree of confidence in achieving complete tumor resection. Given the unique activation mechanism of targeting a universally dysregulated tumor metabolic signature, pegsitacianine could be beneficial in aiding surgical oncologists across multiple tumor disciplines.”

The recently completed Phase 2 study (NCT03735680) was a non-randomized, open-label, multi-center study being conducted at three U.S. sites. This exploratory study further confirmed the selected dose-schedule, expanded upon the drug’s safety profile and increased the number of tumor types in which pegsitacianine imaging was shown to be feasible. Together, the results demonstrated that pegsitacianine is well-tolerated in patients and provides the surgeon with accurate, real-time feedback in the operating room. Intraoperative imaging observations demonstrated a high correlation with the pathological assessments of collected tissues, and imaging can be reliably performed using multiple FDA-cleared NIR imaging devices. Results from evaluable patients demonstrated favorable sensitivity (100%) and specificity (92%) values, as well as a strong negative predictive value (100%) for detecting histologically normal tissue that was collected as part of standard of care surgery.

“The high sensitivity and specificity valuesfrom the Phase 2 trial not only corroborated our Phase 1 observations to further support the use of OncoNano’s ON-BOARDTM platform in surgical imaging, but also highlight the potential benefit of this pH-activatable platform for tumor-targeted delivery of therapeutic payloads with an increased therapeutic window,” commented Jinming Gao, PhD, OncoNano’s Chief Scientific Officer.

More information on the Phase 2 trial can be found at ClinicalTrials.Gov

About OncoNano Medicine

OncoNano Medicine is developing a new class of products that exploit pH as a biomarker to diagnose and treat cancer with high specificity. Our product candidates and interventions are designed to help patients across the continuum of cancer care and include solid tumor therapeutics, agents for real-time image-guided surgery and a platform of product candidates that activate and guide the body’s immune system to target cancer. OncoNano’s lead development candidate is pegsitacianine, a novel fluorescent nanoprobe, that is currently under study in Phase 2 clinical trials as a real-time surgical imaging agent for use in multiple cancer surgeries. ONM-501, OncoNano’s second development program, is a next generation STING (STimulator of INterferon Genes) agonist that is advancing towards a first in human trial in the second half of 2022. Learn more at

Lauren Arnold