Endocyte to Advance Development of EC1069, a PSMA-Targeted Small Molecule Drug Conjugate Therapy for Prostate Cancer

Company Expects to File IND for Therapeutic Agent in 2013

Human Study of Companion Imaging Agent EC0652 Demonstrates Safety and Binding Specificity

WEST LAFAYETTE, Ind., Jan. 29, 2013 (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 the achievement of key objectives in a Phase 0 study of EC0652, a diagnostic imaging agent targeting prostate specific membrane antigen (PSMA), a protein expressed on cancer cells originating from the prostate as well as on tumor neovasculature. Based on the observed safety of the agent and its specificity for binding to diseased cells, Endocyte is advancing the development of both the diagnostic imaging agent, EC0652, and the corresponding therapeutic agent, EC1069, a proprietary PSMA-targeted SMDC linked with the potent anti-cancer drug tubulysin. Endocyte expects to file an Investigational New Drug (IND) application for EC1069 by the end of 2013.

The new prostate cancer imaging agent EC0652, also termed DUPA-^99mTc, is a conjugate of a high affinity PSMA-targeting ligand, 2-[3-(1, 3-dicarboxy propyl)-ureido] pentanedioic acid (DUPA) to technetium 99m (^99mTc). The discovery process utilized a unique structure-based drug design approach to synthesize the ideal targeting ligand for binding to PSMA. The corresponding SMDC, EC1069, utilizes the same targeting ligand.

"DUPA has demonstrated excellent localization to prostate cancer regionally and at distant sites," said Thomas A. Gardner, M.D., professor of urology at Indiana University Health. "These results encourage us to investigate this novel agent for both imaging and therapeutic applications for prostate cancer."

"We have generated a number of unique development methods to optimize the design of our targeting ligands and maximize specificity, and our approach is yielding superior results with new ligands of much higher specificity than other methods," commented Philip Low, Ph.D., Endocyte's chief science officer. "We are also using this approach to develop ligands to target several other diseases as we continue to expand our SMDC platform." 

The imaging study is being led by the Purdue University Center for Cancer Research and performed at the Department of Urology at the Indiana University School of Medicine. Detailed results of this study are anticipated to be presented at an upcoming medical conference.

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 www.endocyte.com.

Forward-Looking Statements

Certain of the statements made in this press release are forward-looking, such as those, among others, relating to future regulatory filings, development of effective targeting ligands, and expansion of Endocyte's SMDC platform. Actual results or developments may differ materially from those projected or implied in these forward-looking statements. Factors that could cause such a difference include risks of delays in conducting studies required for regulatory filings (which delays might be caused, for example, by unanticipated challenges in manufacturing compounds on the scale necessary to conduct such studies), technical and scientific risks associated with developing targeting ligands with superior specificity or other characteristics, and risks related to the safety and efficacy of Endocyte's product candidates. More information about the risks and uncertainties faced by Endocyte is contained in its periodic reports filed with the Securities and Exchange Commission. Endocyte disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

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         Martina Schwarzkopf, Ph.D., Russo Partners,
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         Tony Russo, Ph.D., Russo Partners,
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