New Published Data Demonstrate Endocyte's Targeted Small Molecule Drug Conjugate Approach Shows Promising Results in Polycystic Kidney Disease Model

New Published Data Demonstrate Endocyte's Targeted Small Molecule Drug Conjugate Approach Shows Promising Results in Polycystic Kidney Disease Model
Study Evaluating Folate-Conjugated Rapamycin Published Online in Journal of the American Society of Nephrology (JASN)

WEST LAFAYETTE, Ind., Aug. 3, 2012 (GLOBE NEWSWIRE) -- Endocyte, Inc. (Nasdaq:ECYT), a biopharmaceutical company developing targeted small molecule drug conjugates (SMDCs) and companion imaging diagnostics for personalized therapy, today announced that Endocyte's approach of utilizing a SMDC targeted to the folate receptor (FR) may provide a promising treatment for patients with autosomal-dominant polycystic kidney disease (ADPKD). In a mouse model of polycystic kidney disease (PKD), treatment with a folate-conjugated form of rapamycin, FC-rapa, (EC0371) strongly attenuated proliferation and growth of renal cysts and preserved renal function. The results were published online ahead of print in the Journal of the American Society of Nephrology and will be available in print in the October issue.

Endocyte chemically synthesized EC0371 by linking the folic acid targeting ligand with the rapamycin drug payload. Rapamycin, a potent inhibitor of mTOR, is a promising drug for PKD therapy. The mTOR pathway is deregulated in ADPKD, and its inhibition reverses renal cystogenesis in animal models. However, in previous clinical trials treatment was limited by the amount of the untargeted rapamycin that could be safely administered. In collaboration with Thomas Weimbs, Ph.D., associate professor in the department of molecular, cellular, and developmental biology, at the University of California, Santa Barbara, at Santa Barbara, Calif., and corresponding author of the publication, the membranes of both human and mouse PKD cysts were found to express the FR, which is the target of the EC0371's high affinity ligand. Results of this study showed that EC0371 inhibits the mTOR pathway activity in a dose- and FR-dependent manner.

"Currently, there is no pharmaceutical treatment available for PKD patients, and patients with end stage renal failure get lifelong dialysis or receive a kidney transplant. Being a PKD patient myself, I have experienced the unmet medical need first hand," said Christopher Leamon, Ph.D., vice president of research and development for Endocyte and co-author of the publication. "I happened to read an article published by Dr. Weimbs where he demonstrated that rapamycin was highly effective in PKD animal models. Suspecting that cystic membranes in PKD tissue might express the FR, I contacted him to discuss the potential for targeting potent drugs exactly where they were needed to stop cystic growth. Our results with EC0371 are very exciting, demonstrating that we may be able to reduce the side effects observed in the clinical trials with untargeted rapamycin by delivering the drug directly to the cystic cells. What we have observed here also reinforces Endocyte's concept of targeted drug delivery."

Over 600,000 people in the United States and 12 million worldwide are affected by the inherited kidney disease known as autosomal-dominant polycystic kidney disease (ADPKD, or PKD). The disease is characterized by the proliferation of thousands of cysts that eventually debilitate the kidneys, causing kidney failure in half of all patients by the time they reach age 50. PKD is one of the leading causes of renal failure in the United States.

About Endocyte

Endocyte is a biopharmaceutical company developing targeted therapies for the treatment of cancer and inflammatory diseases. Endocyte uses its proprietary technology to create novel SMDCs and companion imaging diagnostics for personalized targeted therapies. The company's SMDCs actively target receptors that are over-expressed on diseased cells, relative to healthy cells. This targeted approach is designed to enable the treatment of patients with highly active drugs at greater doses, delivered more frequently, and over longer periods of time than would be possible with the untargeted drug alone. The companion imaging diagnostics are designed to identify patients whose disease over-expresses the target of the therapy and who are therefore more likely to benefit from treatment.

For additional information, please visit Endocyte's website at