January 2014 Revolutionizing the Treatment of Cancer 2 Safe Harbor Statement The statements that follow (including projections and business trends) are forward-looking statements. Rexahn's actual results may differ mater

Revolutionizing the Treatment of Cancer

Safe Harbor Statement

The statements that follow (including projections and business trends) are forward-looking

statements. Rexahn's actual results may differ materially from anticipated results, and

expectations expressed in these forward-looking statements, as a result of certain risks and

uncertainties, including Rexahn's lack of profitability, the need for additional capital to

operate its business to develop its product candidates; the risk that Rexahn's development

efforts relating to its product candidates may not be successful; the possibility of being unable

to obtain regulatory approval of Rexahn's product candidates; the risk that the results of

clinical trials may not be completed on time or support Rexahn's claims; demand for and

market acceptance of Rexahn's drug candidates; Rexahn's reliance on third party researchers

and manufacturers to develop its product candidates; Rexahn's ability to develop and obtain

protection of its intellectual property; and other risk factors set forth from time to time in our

filings with the Securities and Exchange Commission. Rexahn assumes no obligation to update

these forward-looking statements.

Rexahn: Revolutionizing the Treatment of Cancer

Identify novel drug targets which are specific to cancer cells:

Increased efficacy, reduced toxicity

Efficacy against multiple drug resistant cancer cells

Synergism with existing cytotoxic compounds

Develop in-licensed targeted drug delivery platforms:

Nano-Polymer-Drug Conjugate System (NPDCS) combines existing

anticancer agents with a polymer/signaling moiety which directs the

drug directly to the tumor

Lipid-Coated Albumin Nanoparticle (LCAN) to enhance delivery of

Deep Oncology Pipeline

Targeted Drug Delivery Platform

- Anticipated progress during 2014

SupinoxinTM(RX-5902)

Supinoxin: Best-in-Class p68 Helicase Inhibitor

n Inhibition of phosphorylated p68 RNA helicase

n Blocks upregulation of cancer related genes

n Solid tumors: pancreas, NSCLC, colon, renal and other solid

n Anti-proliferative effects

n Synergistic with cytotoxic agents

n Efficacy against drug resistant cancer cells

n Orally bioavailable

n New chemical entity with a strong patent position

n Phase I clinical trial in cancer patients initiated August 2013

n Initial data expected in Q1 2014

Clinical Development

Supinoxin: Mechanism of action

n Phosphorylated p68 is highly

expressed in cancer cells but not in

normal cells, and upregulates

cancer-related genes

n Supinoxin selectively inhibits

phosphorylated p68 RNA Helicase

Decreased proliferation/growth

Synergism with cytotoxic agents

Activity against drug resistant

Cancer cell Proliferation/Tumor growth

Supinoxin: Increased Survival in Human Renal Cell

Carcinoma and Pancreatic Cancer Xenograft Models

Treatment with Supinoxin on days 1

to 20 produced a survival benefit

RX-3117: Novel DNA synthesis inhibitor

n Cancer cell specific nucleoside compound that inhibits DNA

n Activated by UCK1 & UCK2

n Solid tumors: pancreas, NSCLC, colon, renal and other solid

n Effective against gemcitabine-resistant human cancer cell

n Orally administered

n Specifically targeted against cancer cells; reduced adverse

n New chemical entity with a strong patent position

n Completed exploratory Phase I clinical trial in cancer patients

Confirmed oral bioavailability and safety

n Phase Ib clinical trial in cancer patients initiated Dec 2013

Clinical Development

RX-3117: Compelling Efficacy in Animal Models

RX-3117 has shown robust anti-tumor effects across a broad variety

of tumor types in animal models (Colon, Non-Small Cell Lung, Small

Cell Lung, Pancreatic, Renal, Ovarian and Cervical)

RX-3117: Compelling Efficacy in Animal Models

RX-3117 offers significant benefits based on overall-survival via oral

administration in nude mice

RX-3117: Efficacy in Gemcitabine-Resistant Cell Lines

The efficacy of RX-3117 was examined in 12 different human tumor

(Colon, Non-Small Cell Lung, Small Cell Lung, Pancreatic, Renal,

Ovarian and Cervical)

RX-3117: Exploratory Phase I clinical Trial (Completed)

n Exploratory Phase I clinical trial in cancer patients was conducted in Europe in 2012

Evaluate oral bioavailability and pharmacokinetics

Assess safety and tolerability

n Drug administration cohorts:

Nine subjects, ages 47 to 67 years, were enrolled

RX-3117 was orally bioavailable with Tmax of 2-3 hours, T1/2 of 14-21 hours, and

oral bioavailability of 33 to 56%

RX-3117 was well tolerated with no post-dose adverse events, laboratory

abnormalities, or ECG changes emerging through 7 days of follow-up

RX-3117: Phase Ib Study Design (ongoing)

n Initiated December 2013

n Cancer patients with solid tumors

n Up to 30 patients and three clinical sites

n Treatment cycle is 28 days

Dosing 3 times a week for 3 weeks followed by 1 week off

n Dose Finding Study Design

Escalation decisions based on safety, dosing, PK, laboratory, etc

Patients may receive up to 8 cycles of treatment

Anti-tumor activity secondary endpoint