Immunology

Rexahn Pharmaceuticals, Inc. (NYSE MKT:RNN) a clinical stage biopharmaceutical company developing best-in-class therapeutics for the treatment of cancer, is providing an overview of its three clinical development programs and financial results for the year ended December 31, 2013.

"Last year was a year of transition for Rexahn as we re-focused our efforts to build a pipeline of oncology assets and raised a significant amount of capital to support the clinical development of our three programs," commented Rexahn's Chief Executive Officer, Peter D. Suzdak, Ph.D. "We are very excited about the progress of the Supinoxin^™, RX-3117, and Archexin^® clinical development programs, and we believe that 2014 will be a transformational year for Rexahn with clinical data expected from all three programs. I look forward to updating our shareholders on the upcoming milestones as appropriate and appreciate their support."

Pipeline Update:

Supinoxinâ„¢ (RX-5902)

A Phase I dose-escalation clinical trial of Supinoxin (RX-5902) in cancer patients with solid tumors began enrolling patients in August 2013. The study is still ongoing and the maximum tolerated dose (MTD) has not yet been achieved. Three dosing cycles have been completed (25, 50 and 100 mg), and no drug related adverse events have been reported. The fourth dosing cycle (150 mg) has been initiated. Two patients have received two cycles of treatment, and one patient has received six cycles of treatment. Pharmacokinetic analysis has shown that Supinoxin displays dose-proportional exposure and an estimated oral bioavailability of 51%. The pharmacokinetic profile of Supinoxin is similar to what has been seen in preclinical studies. Rexahn expects to complete this trial and announce final results in the fourth quarter of 2014.

RX-3117

Rexahn initiated a Phase Ib clinical trial of RX-3117 in cancer patients with solid tumors in January 2014. The Phase Ib trial is a multi-center dose-escalation study which will evaluate the safety, tolerability, dose-limiting toxicities and MTD of RX-3117 in cancer patients with solid tumors. Secondary endpoints will include characterizing the pharmacokinetic profile of RX-3117 and evaluating the preliminary anti-tumor effects of RX-3117. Rexahn expects to complete patient enrollment of the RX-3117 Phase I clinical trial in the fourth quarter of 2014 or early 2015.

Archexin^®

Rexahn initiated a Phase IIa Archexin proof-of-concept clinical trial in patients with metastatic renal cell carcinoma (RCC) in January 2014. Rexahn has previously received orphan drug designation for this indication. The trial is a multi-center study designed to evaluate the efficacy of Archexin in combination with everolimus (Afinitor®) to treat metastatic RCC patients and will be conducted in two stages. The first stage will be dose ranging, with up to three cohorts of three RCC patients to determine its MTD in combination with everolimus. Once the MTD has been determined, thirty RCC patients will be randomized for treatment with either Archexin in combination with everolimus or everolimus alone, in a ratio of 2:1. Rexahn plans to complete the initial component of this trial in the fourth quarter of 2014.

Additional Highlights from 2013: