Navidea Biopharmaceuticals, Inc. (NYSE:NAVB) ("Navidea" or the "Company"), a company focused on the development of precision immunodiagnostic agents and immunotherapeutics, today announced the granting of a National Institutes of Health ("NIH") award to the University of California San Diego School of Medicine for the proposal entitled, "Renal Molecular Imaging of Mesangial Cell Function with Tc-99m-Tilmanocept." The award (Project Number: 1R01DK127201-01), from the National Institute of Diabetes and Digestive and Kidney Diseases of the NIH, was granted to Co-Principal Investigators UC San Diego faculty Carl Hoh, MD and David Vera, PhD, of the Department of Radiology, and Charles Ginsberg, MD, MAS, of the Department of Medicine, Division of Nephrology.
The worldwide prevalence of diabetes is expected to increase to 642 million within two decades. Approximately 40% of people with diabetes will go on to develop diabetic nephropathy ("DN") – a form of chronic kidney disease ("CKD"). Typically, diabetic nephropathy develops relatively slowly over the course of decades, as indicated by slow increases in certain serum and urine markers over time. The current standard-of-care for monitoring the development of CKD is periodic assessment of these aforementioned markers. However, twenty percent of diabetic patients who develop CKD experience a more rapid development of DN. Consequently, there is an unmet medical need for routine surveillance during the first decade of CKD.
In this Phase 1 clinical study being conducted at UC San Diego Health, Tc99m tilmanocept will be used as an imaging agent to evaluate a key component of the kidneys, the mesangial cells, as a biomarker for diabetic nephropathy. The molecular target for Tc99m tilmanocept, CD206, is expressed on these mesangial cells of the kidney. The expansion of mesangial cells is an early hallmark of diabetic nephropathy, and the ability to reliably image them noninvasively could provide an important tool for physicians to evaluate diabetic patients for early signs of the disease.
This trial will be an open-label study investigating the biodistribution at two dose levels (2.0 and 20 nmol) of Tc99m tilmanocept. Four groups of patients at each dose (10 subjects each), will be studied: 1) No CKD, 2) early CKD, 3) moderate CKD, and 4) advanced CKD. Within each group, 50% of participants will have diabetes. Expected results include kidney image sets and biodistribution of Tc99m tilmanocept that reflects pathology. This study is a necessary step toward FDA approval of Tc99m tilmanocept as a kidney imaging agent.
From the proposal's Public Health Relevance Statement: "This proposal will use kidney SPECT/CT of Tc-99m-tilmanocept to evaluate the mesangial changes seen in diabetics across the spectrum of kidney disease as well as persons with hypertensive kidney disease, the next most common cause of kidney disease in patients with diabetes. We aim to demonstrate that these different disease types and stages can be differentiated with Tc-99m-tilmanocept SPECT/CT and can thus be used for future trials evaluating early diagnosis and treatment of diabetic nephropathy."
Dr. David Vera, Co-Principal Investigator, said, "Our goal is a simple ‘first-line' diagnostic tool for nephrologists to determine which of their patients with diabetes are at risk of chronic kidney disease." Dr. Hoh added, "an additional potential benefit to a Tc-99m-tilmanocept kidney imaging study may be an additional modality for screening of renal cancer." Dr. Ginsberg stated, "considering the increasing armament of drugs to combat diabetic nephropathy, an imaging study that can diagnose this disease early in its course has tremendous therapeutic implications."
Dr. Michael Rosol, Chief Medical Officer for Navidea, said, "We are pleased that the NIH has funded this important Phase 1 study at UC San Diego, run in part by the inventor of tilmanocept, Dr. David Vera." Dr. Rosol continued, "Navidea has had a long and productive relationship with Dr. Vera and his collaborators at UC San Diego, and we will be keenly watching for the results of this study addressing this area of large unmet clinical need. Today's announcement exemplifies the broad reach of our tilmanocept platform. The development pipeline remains robust and we are excited to continue developing new and valuable applications for our core technology."
Dr. Vera, together with Drs Anne Wallace and Carl Hoh, developed Tc99m tilmanocept at UC San Diego Moores Cancer Center as an agent to help detect and map cancers that have reached the lymph nodes. Cancer clinical trials showed that it better detected cancer and provided more accurate staging.