Opus Genetics (IRD) 10-Q 3 Nov 17 2017 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2017	Nov. 03, 2017
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2017
Entity Registrant Name	REXAHN PHARMACEUTICALS, INC.
Entity Central Index Key	1,228,627
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3
Trading Symbol	rnn
Entity Common Stock, Shares Outstanding		31,725,114

Condensed Balance Sheet

Condensed Balance Sheet - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Current Assets:
Cash and cash equivalents	$ 8,226,189	$ 11,578,473
Marketable securities	14,977,346	8,737,107
Prepaid expenses and other current assets	1,277,604	608,517
Total Current Assets	24,481,139	20,924,097
Security Deposits	30,785	30,785
Equipment, Net	79,056	88,650
Total Assets	24,590,980	21,043,532
Current Liabilities:
Accounts payable and accrued expenses	2,338,777	1,882,500
Deferred Research and Development Arrangement	393,750	450,000
Other Liabilities	61,557	79,204
Warrant Liabilities	6,676,091	1,573,366
Total Liabilities	9,470,175	3,985,070
Commitments and Contingencies (note 14)
Stockholders' Equity:
Preferred stock, par value $0.0001, 10,000,000 authorized shares, none issued and outstanding
Common stock, par value $0.0001, 50,000,000 authorized shares, 28,459,805 and 23,736,878 issued and outstanding	2,846	2,374
Additional paid-in capital	151,858,173	132,086,419
Accumulated other comprehensive loss	(13,965)	(6,122)
Accumulated deficit	(136,726,249)	(115,024,209)
Total Stockholders' Equity	15,120,805	17,058,462
Total Liabilities and Stockholders' Equity	$ 24,590,980	$ 21,043,532

Condensed Balance Sheet (Parent

Condensed Balance Sheet (Parenthetical) - $ / shares	Sep. 30, 2017	Dec. 31, 2016
Condensed Balance Sheet [Abstract]
Preferred Stock, Par Value	$ 0.0001	$ 0.0001
Preferred Stock, Shares Authorized	10,000,000	10,000,000
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0
Common Stock, Par Value	$ 0.0001	$ 0.0001
Common Stock, Shares Authorized	50,000,000	50,000,000
Common Stock, Shares, Issued	28,459,805	23,736,878
Common Stock, Shares, Outstanding	28,459,805	23,736,878

Condensed Statement Of Operatio

Condensed Statement Of Operations - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Condensed Statement Of Operations [Abstract]
Revenues:
Expenses:
General and administrative	1,574,323	1,418,990	5,004,832	4,490,145
Research and development	2,644,999	2,298,585	7,451,656	8,004,193
Total Expenses	4,219,322	3,717,575	12,456,488	12,494,338
Loss from Operations	(4,219,322)	(3,717,575)	(12,456,488)	(12,494,338)
Other Income (Expense)
Interest income	60,750	26,145	135,329	83,884
Unrealized gain (loss) on fair value of warrants	3,120,500	967,637	(9,047,831)	3,941,682
Financing expense		(143,203)	(333,050)	(313,090)
Total Other Income (Expense)	3,181,250	850,579	(9,245,552)	3,712,476
Net Loss Before Provision for Income Taxes	(1,038,072)	(2,866,996)	(21,702,040)	(8,781,862)
Provision for income taxes
Net Loss	$ (1,038,072)	$ (2,866,996)	$ (21,702,040)	$ (8,781,862)
Net loss per share, basic and diluted	$ (0.04)	$ (0.13)	$ (0.83)	$ (0.42)
Weighted average number of shares outstanding, basic and diluted	28,459,316	21,644,182	26,121,160	21,075,847

Condensed Statement Of Comprehe

Condensed Statement Of Comprehensive Loss - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Condensed Statement Of Comprehensive Loss [Abstract]
Net Loss	$ (1,038,072)	$ (2,866,996)	$ (21,702,040)	$ (8,781,862)
Unrealized gain (loss) on available-for-sale securities	11,740	(6,983)	(7,843)	13,385
Comprehensive Loss	$ (1,026,332)	$ (2,873,979)	$ (21,709,883)	$ (8,768,477)

Condensed Statement Of Cash Flo

Condensed Statement Of Cash Flows - USD ($)	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Cash Flows from Operating Activities:
Net loss	$ (21,702,040)	$ (8,781,862)
Adjustments to reconcile net loss to net cash used in operating activities:
Compensatory stock	31,200	97,649
Depreciation and amortization	30,963	24,123
Amortization of premiums and discounts on marketable securities, net	40,578	21,535
Stock-based compensation	790,006	1,063,589
Amortization of deferred research and development arrangements	(56,250)	(56,250)
Unrealized loss (gain) on fair value of warrants	9,047,831	(3,941,682)
Financing expense	333,050	313,090
Amortization of deferred lease incentive	(9,333)	(9,333)
Deferred lease expenses	(8,314)	(8,787)
Changes in assets and liabilities:
Prepaid expenses and other assets	(669,087)	419,765
Accounts payable and accrued expenses	456,277	(875,574)
Net Cash Used in Operating Activities	(11,715,119)	(11,733,737)
Cash Flows from Investing Activities:
Purchase of equipment	(21,369)	(8,263)
Purchase of marketable securities	(15,008,660)	(8,747,423)
Redemption of marketable securities	8,720,000	8,560,000
Net Cash Used in Investing Activities	(6,310,029)	(195,686)
Cash Flows from Financing Activities:
Issuance of common stock and units, net of issuance costs	9,241,271	10,122,223
Proceeds from exercise of stock warrants	5,354,093
Proceeds from exercise of stock options	77,500
Net Cash Provided by Financing Activities	14,672,864	10,122,223
Net Decrease in Cash and Cash Equivalents	(3,352,284)	(1,807,200)
Cash and Cash Equivalents - beginning of period	11,578,473	10,199,440
Cash and Cash Equivalents - end of period	8,226,189	8,392,240
Non-cash financing and investing activties:
Warrants issued	4,107,488	$ 4,364,110
Warrant liability extinguishment from exercise of warrants	$ 8,052,594

Operations And Organization

Operations And Organization	9 Months Ended
	Sep. 30, 2017
Operations And Organization [Abstract]
Operations And Organization	1. Operations and Organization Operations Rexahn Pharmaceuticals, Inc. (the “Company”), a Delaware corporation, is a biopharmaceutical company whose principal operations are the discovery, development and commercialization of innovative treatments for cancer. The Company had an accumulated deficit of $ 13 6,726,2 49 at September 30, 2017 and anticipates incurring losses through fiscal year 2017 and beyond. The Company has not yet generated commercial revenues and has funded its operating losses to date through the sale of shares of its common stock and warrants to purchase shares of its common stock, convertible debt, interest income from cash, cash equivalents and marketable securities, and proceeds from reimbursed research and development costs. The Company believes that its cash, cash equivalents, and marketable securities will be sufficient to cover its cash flow requirements for its current activities for at least the next 12 months from the date these financial statements were issued. Management believes it has the capability of managing the Company’s operations within existing cash available by focusing on select research and development activities, selecting projects in conjunction with potential financings and milestones, and efficiently managing the Company’s general and administrative affairs.  Basis of Presentation The accompanying unaudited condensed financial statements of the Company have been prepared pursuant to the rules and regulations of the U.S. Securities and Exchange Commission for interim financial information. Accordingly, they do not include all of the information and footnotes required by accounting principles generally accepted in the United States (“U.S. GAAP”) for complete financial statements. In the opinion of the Company’s management, all adjustments (consisting of only normal recurring accruals) considered necessary for a fair presentation of the Company’s financial position as of September 30, 2017 and December 31, 2016 and of the results of operations and comprehensive loss for the three and nine months ended September 30, 2017 and 2016 and cash flows for the nine months ended September 30, 2017 and 2016 have been included. Operating results for the three and nine months ended September 30, 2017 are not necessarily indicative of results that may be expected for any other interim period or the full fiscal year ending December 31, 2017. The accompanying unaudited condensed financial statements should be read in conjunction with the audited financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 (the “2016 Form 10-K”). Information included in the condensed balance sheet as of December 31, 2016 has been derived from the Company’s audited financial statements for the year ended December 31, 2016 included in the 2016 Form 10-K.  Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. These estimates are based on management’s best knowledge of current events and actions the Company may undertake in the future. Actual results may ultimately differ from these estimates. These estimates are reviewed periodically, and as adjustments become necessary, they are reported in earnings in the period in which they become available.   

Recent Accounting Pronouncement

Recent Accounting Pronouncements Affecting the Company	9 Months Ended
	Sep. 30, 2017
Recent Accounting Pronouncements Affecting the Company [Abstract]
Recent Accounting Pronouncements Affecting the Company	2. Recent Accounting Pronouncements Affecting the Company Revenue from Contracts with Customers  In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-09, “Revenue from Contracts with Customers,” a comprehensive new revenue recognition standard that will supersede nearly all existing revenue recognition guidance under U.S. GAAP. The standard’s core principle is that a company should recognize revenue when it transfers goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods and services, and provides a revenue recognition framework in accordance with this principle. On August 12, 2015, the FASB issued ASU 2015-14, which defers the effective date of ASU 2014-09 by one year to December 15, 2017 for annual reporting periods beginning after that date and interim periods therein. The Company expects to adopt this standard for the annual reporting period beginning January 1, 2018. As the Company currently does not have revenue contracts, the Company does not expect the adoption of this standard to have a material impact on the operating results of the Company  Leases  In February 2016, the FASB issued ASU 2016-02, “Leases,” which requires an entity to recognize assets and liabilities arising from leases on the balance sheet and to provide additional disclosures about leasing arrangements. ASU 2016-02 will be effective for reporting periods beginning after December 15, 2018, with early adoption permitted. The Company is currently evaluating the impact the adoption of this guidance will have on its financial statements.  Compensation-Stock Compensation  In March 2016, the FASB issued ASU 2016-09, “Compensation-Stock Compensation: Improvements to Employee Share Based Payment Accounting,” which includes multiple provisions intended to simplify various aspects of accounting for share-based payments. The guidance is effective for reporting periods beginning after December 15, 2016, with early adoption permitted. The Company adopted this guidance for the three months ended March 31, 2017. This pronouncement did not have a material impact on the financial statements.  

Marketable Securities

Marketable Securities	9 Months Ended
	Sep. 30, 2017
Marketable Securities [Abstract]
Marketable Securities	 3 . Marketable Securities  Marketable securities are considered “available-for-sale” in accordance with FASB Accounting Standards Codification (“ASC”) 320, “Debt and Equity Securities,” and thus are reported at fair value in the Company’s accompanying balance sheet, with unrealized gains and losses excluded from earnings and reported as a separate component of stockholders’ equity. Amounts reclassified out of accumulated other comprehensive income (loss) into realized gains and losses are accounted for on the basis of specific identification and are included in other income or expense in the statement of operations. The Company classifies such investments as current on the balance sheet as the investments are readily marketable and available for use in current operations.  The following table shows the Company’s marketable securities’ adjusted cost, gross unrealized gains and losses, and fair value by significant investment category as of September 30, 2017 and December 31, 2016:    September 30, 2017  Cost Gross Unrealized Gross Unrealized Fair  Basis Gains Losses Value  Commercial Paper $ 3,230,566 $ - $ (1,983) $ 3,228,583  Corporate Bonds 11,760,745 142 (12,124) 11,748,763  Total Marketable Securities $ 14,991,311 $ 142 $ (14,107) $ 14,977,346   December 31, 2016  Cost Gross Unrealized Gross Unrealized Fair  Basis Gains Losses Value  Certificates of Deposit $ 720,000 $ 197 $ - $ 720,197  Commercial Paper 3,987,424 - (1,684) 3,985,740  Corporate Bonds 4,035,805 - (4,635) 4,031,170  Total Marketable Securities $ 8,743,229 $ 197 $ (6,319) $ 8,737,107  The Company typically invests in highly-rated securities, with the primary objective of minimizing the potential risk of principal loss. As of September 30, 2017, the Company had three investments of commercial paper with an aggregate fair value of $ 3,228,583 and unrealized losses of $ 1,983 , and 1 1 corporate bonds with an aggregate fair value of $ 11,249,968 and unrealized losses of $ 1 2,124 all of which have been unrealized losses for less than 12 months. The Company does not intend to sell its marketable securities in an unrealized loss position. Based upon these securities’ fair value relative to the cost, high ratings, and volatility of fair value, the Company considers the declines in market value of its marketable securities to be temporary in nature, does not consider any of its investments other-than-temporarily impaired, and anticipates that it will recover the entire amortized cost basis.  The amortized cost basis and fair value of marketable securities by contractual maturity are:    Maturity Cost Basis Fair Value  Less than 1 year $ 11,963,973 $ 11,955,906  1 to 5 years 3,027,338 3,021,440  Total Marketable Securities $ 14,991,311 $ 14,977,346 

Prepaid Expenses And Other Curr

Prepaid Expenses And Other Current Assets	9 Months Ended
	Sep. 30, 2017
Prepaid Expenses And Other Current Assets [Abstract]
Prepaid Expenses And Other Current Assets	4 . Prepaid Expenses and Other Current Assets     September 30, December 31,  2017 2016   Deposits on contracts $ 611,550 $ 179,476  Prepaid expenses and other current assets 666,054 429,041   $ 1,277,604 $ 608,517 Deposits on contracts consist of deposits on research and development contracts for services that had not been incurred as of the balance sheet date. Prepaid expenses and o ther assets include prepaid general and administrative expense s, such as insurance, rent , investor relations fees and compensatory stock issued for services not yet incurred as of the balance sheet date.

Equipment, Net

Equipment, Net	9 Months Ended
	Sep. 30, 2017
Equipment, Net [Abstract]
Equipment, Net	5. Equipment, Net     September 30, December 31,  2017 2016   Furniture and fixtures $ 78,794 $ 78,794  Office and computer equipment 121,817 113,932  Lab equipment 445,134 431,650  Leasehold improvements 133,762 133,762   Total equipment 779,507 758,138  Less: Accumulated depreciation and amortization (700,451) (669,488)   Net carrying amount $ 79,056 $ 88,650

Accounts Payable And Accrued Ex

Accounts Payable And Accrued Expenses	9 Months Ended
	Sep. 30, 2017
Accounts Payable And Accrued Expenses [Abstract]
Accounts Payable And Accrued Expenses	6. Accounts Payable and Accrued Expenses      September 30, December 31,  2017 2016   Trade payables $ 462,602 $ 430,013  Accrued expenses 142,270 141,190  Accrued research and development contract costs 1,163,545 499,889  Payroll liabilities 570,360 811,408   $ 2,338,777 $ 1,882,500 

Deferred Research And Developme

Deferred Research And Development Arrangement	9 Months Ended
	Sep. 30, 2017
Deferred Research And Development Arrangement [Abstract]
Deferred Research And Development Arrangement	7 . Deferred Resea rch and Development Arrangement Rexgene Biotech Co., Ltd. In 2003, the Company entered into a collaborative research agreement with Rexgene Biotech Co., Ltd. (“Rexgene”), a shareholder. Rexgene is engaged in the development of pharmaceutical products in Asia and has agreed to assist the Company with the research, development and clinical trials necessary for registration of the Company’s drug candidate Archexin® in Asia. This agreement provides Rexgene with exclusive rights to license, sublicense, make, have made, use, sell and import Archexin in Asia. In accordance with the agreement, Rexgene paid the Company a one-time fee of $ 1, 500,000 in 2003. The agreement terminates at the later of 20 years or the term of the patent. The amortization reduces research and development expenses for the periods presented. The Company is using 20 years as its basis for recognition and accordingly , research and devel opment expenses were reduc ed by $18,750 for each of the three month periods ended September 30, 2017 and 2016 and $56,250 fo r each of the nine month periods ended September 30, 2017 and 2016. The remaining $ 393,75 0 and $ 450,000 to be amortized at September 30, 2017 and December 31, 2016, respectively, is reflected as a deferred resea rch and development arrangement on the balance sheet. The payment from Rexgene is being used in the cooperative funding of the costs of development of Archexin. Royalties of 3 % of net sales of licensed products will become payable by Rexgene to the Company on a quarterly basis once commercial sales of Archexin begin in Asia. The product is still under development and commercial sales in Asia are not expec ted to begin until at least 2018 . 

Other Liabilities

Other Liabilities	9 Months Ended
	Sep. 30, 2017
Other Liabilities [Abstract]
Other Liabilities	8 . Other Liabilities  Deferred Lease Incentive  In accordance with the Company’s office lease agreement, as amended and further discussed in Note 14, the Company has been granted leasehold improvement allowances from the lessor to be used for the construction cost of improvements to the leased property, which included architectural and engineering fees, government agency plan check, permit and other fees, sales and use taxes, testing and inspection costs and telephone and data cabling and wiring in the premises. The Company accounted for the benefit of the leasehold improvement allowance as a reduction of rental expense over the term of the office lease. The following table sets forth the cumulative deferred lease incentive:     September 30, December 31,  2017 2016   Deferred lease incentive $ 154,660 $ 154,660  Less accumulated amortization (132,884) (123,551)   Balance $ 21,776 $ 31,109 Deferred Office Lease Expense The lease agreement , as amended, provided for an initial annual base rent with annual increases over the lease term. The Company recognizes rental expense on a straight-line basis over the term of the lease, which resulted in a deferred rent liability of $39,781 and $48,095 as of September 30, 2017 and December 31, 2016, respectively.

Net Loss Per Common Share

Net Loss Per Common Share	9 Months Ended
	Sep. 30, 2017
Net Loss Per Common Share [Abstract]
Net Loss Per Common Share	9 . Net Loss per Common Share Basic loss per common share is computed by dividing net loss by the weighted average number of shares of common stock outstanding for the period. Diluted loss per common share is computed by dividing net loss by the weighted average number of shares of common stock outstanding, plus the number of common share equivalents that would be dilutive. As of September 30, 2017 and December 31, 2016, there were stock options, restricted stock units and warrants to acquire, in the aggregate, 7, 166,209 and 7 ,142,728 shares of the Company’s common stock, respectively, that are potentially dilutive. However, diluted loss per share is the same as basic loss per share for all periods presented because the inclusion of common share equi valents would be anti-dilutive.

Common Stock

Common Stock	9 Months Ended
	Sep. 30, 2017
Common Stock [Abstract]
Common Stock	10. Common Stock The following transactions occurred during the nine months ended September 30, 2017 : Reverse Stock Split On May 5, 2017 the Company effected a one- for- ten reverse stock split of the outstanding shares of the Company’s common stock, together with a corresponding proportional reduction in the number of authorized shares of the Company’s capital stock. Each ten shares of the Company’s common stock, par value $0.0001 per share, issued and outstanding at the effective time of the reverse stock split were reclassified and combined into one share of common stock par value $0.0001 per share. The number of shares of common stock and preferred stock the Company is authorized to issue was reduced to 50 million and 10 million, respectively. All share and per share amounts of common stock, stock options, stock warrants and restricted stock units have been restated for all periods to give retroactive effect to the reverse stock split. Accordingly, an amount equal to the par value of the decreased shares resulting from the reverse stock split was reclassified from “Common stock” to “Additional paid-in capital.”  Warrant Exercises During the nine months ended September 30, 2017 , warrant holders exercised warrants to purchase shares of the Company’s common stock for cash of $ 5,354,093 and the Company issued 1,652,623 shares.  Stock Option Exercises During the nine months ended September 30, 2017 , a stock option holder exercised options to purchase shares of the Company’s common stock for cash of $ 77,500 and the Company issued 25,000 shares.  Compensatory Shares During the nine months ended September 30, 2017 , the Company issued 15,000 shares to a privately held investor relations firm in exchange for investor relations services. The aggregate market value of the stock issued was $ 31,200 . Registered Direct Offering On June 12, 2017 the Company closed a registered direct public offering of 3,030,304 shares of common stock and warrants to purchase up to 1,515,152 shares of common stock. The common stock and warrants were sold in units, consisting of a share of common stock and a warrant to purchase 0.5 shares of common stock, at a price of $3.30 per unit, with an exercise price for the warrants of $4.00 per share . The total gross proceeds of the offering were $10,000,003 . The warrants issued will become exercisable beginning six months after the closing date, and will remain exercisable until the five-year anniversary of the initial exercise date, and were recorded as liabilities at fair value. A summary of the allocation of the proceeds of the offering is shown below:     Gross Proceeds: $ 10,000,003   Allocated to warrant liabilities 3,673,168  Allocated to common stock and additional paid-in capital 6,326,835   Total allocated gross proceeds: $ 10,000,003 The Company also issued warrants to purchase up to an aggregate 181,818 shares of common stock to the placement agent in the offering. The closing costs for the offering of $1,193,052 inc luded $434,320 for the pl acement agent warrants and $758,732 for placement agent and other fees. Based on the estimated fair value of the stock and warrants in the units, the Company allocated $333,050 to financing expense for the warrants and $860,002 as stock issuance costs.

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2017
Stock-Based Compensation [Abstract]
Stock-Based Compensation	11. Stock-Based Compensation As of September 30, 2017, the Company had 1 ,830,443 options to purchase common stock and 47,300 restricted stock units (“RSUs”) outstanding. At the Company’s Annual Meeting of Shareholders held on June 10, 2013, the Company’s shareholders voted to approve the Rexahn Pharmaceuticals, Inc. 2013 Stock Option Plan (the “2013 Plan”). Under the 2013 Plan, the Company grants equity awards to key employees, directors and consultants of the Company. The Company initially reserved 1,700,000 shares of common stock for issuance pursuant to the 2013 Plan, and on April 11, 2017, the Company’s shareholders approved an increase of 1,700,000 shares of common stock reserved for issuance pursuant to the 2013 Plan. As of September 30, 2017, there were 1 ,483,443 options and 47,300 RSUs outstanding under the 2013 Plan, and 1, 868,507 shares were available for issuance. On August 5, 2003, the Company established a stock option plan (the “2003 Plan”). Under the 2003 Plan, the Company granted stock options to key employees, directors and consultants of the Company. With the adoption of the 2013 Plan, no new stock options may be issued under the 2003 Plan, but previously issued options under the 2003 Plan remain outstanding until their expiration. As of September 30, 2017, there were 335,000 options outstanding under the 2003 Plan. In March 2016, the Company granted to a third party an option to purchase up to 12,000 shares of the Company’s common stock. These were the only Company stock options outstanding as of September 30, 2017, that were not issued pursuant to the 2013 Plan or the 2003 Plan. Accounting for Awards Stock-based compensation expense is the estimated fair value of options and RSUs granted amortized on a straight-line basis over the requisite vesting service period for the entire portion of the award. Total stock-based compensation recognized by the Company for the three and nine months ended September 30, 2017 and 2016 is as follows:    For the Three Months Ended September 30, For the Nine Months Ended September 30,  2017 2016 2017 2016  Statement of operations line item:  General and administrative $ 184,914 $ 232,951 $ 580,812 $ 673,064  Research and development 42,700 136,451 209,194 390,525   Total $ 227,614 $ 369,402 $ 790,006 $ 1,063,589 No income tax benefit has been recognized in the statement of operations for stock-based compensation arrangements as the Company has provided for a 100 % valuation allowance on its deferred tax assets. Summary of Stock Option Transactions There were 48 3,260 stock options granted at exercise prices ranging from $1. 84 to $6. 18 with an aggregate fair value of $738,937 during the nine months ended September 30, 2017. There were 5 87,637 stock options granted at exercise prices ranging from $2. 60 to $3. 70 with an aggregate fair value of $ 1,150,513 during the nine months ended September 30, 2016. The majority of the option grants to employees vest over a four -year period from the grant date. The vesting period is either (i) 30% , 30% and 40% on the first , second and third anniversaries of the grant date, respectively, or (ii) 25% each on the first four anniversaries of the grant date. With the exception of the options granted in March 2016, which have a three -year term, options generally expire ten years from the date of grant. For the majority of grants to non-employee consultants of the Company, the vesting period is between one and three years, subject to the fulfillment of certain conditions in the individual stock agreements, or 100% upon the occurrence of certain events specified in the individual stock agreements. The fair value of options at the date of grant was estimated using the Black-Scholes option pricing model. The Company took into consideration guidance under ASC 718, “Compensation-Stock Compensation” and Staff Accounting Bulletin No. 107 (“SAB 107”) when reviewing and updating assumptions. The expected volatility is based upon historical volatility of the Company’s stock. The expected term is based upon the simplified method as allowed under SAB 107.  The assumptions made in calculating the fair values of options are as follows:     Nine Months Ended September 30,  2017 2016  Black-Scholes assumptions  Expected dividend yield 0 % 0 %  Expected volatility 69-79 % 31-75 %  Risk free interest rate 1.8 -2.0 % 0.8 - 1.4 %  Expected term (in years) 5.5 -6 years 2 -6 years A summary of stock option activity for the nine months ended September 30, 2017 is as follows:     Number of Options Weighted Average Exercise Price Weighted Average Remaining Contractual Term Aggregate Intrinsic Value  Outstanding, January 1, 2017 1,690,037 $ 6.20 7.3 years $ -  Granted 483,260 $ 2.37  Exercised (25,000) $ 3.10  Expired (15,000) $ 16.07  Cancelled (302,854) $ 5.00   Outstanding, September 30, 2017 1,830,443 $ 5.35 7.4 years $ 194,644  Exercisable, September 30, 2017 1,068,630 $ 6.60 6.3 years $ -   The total intrinsic value of options exercised was $97,872 for the nine months ended September 30, 2017. There were no stock options exercised during the three months ended September 30, 2017 or the three and nine months ended September 30, 2016. The weighted average fair value of the options granted was $1.53 and $ 1.96 for the nine months ended September 30, 2017 and 2016, respectively. A summary of the Company’s unvested options as of September 30, 2017 and changes during the nine months ended September 30, 2017 is presented below:     2017  Number of Options Weighted Average Fair Value at Grant Date  Unvested at January 1, 2017 897,123 $ 3.21  Granted 483,260 $ 1.53  Vested (458,968) $ 3.12  Cancelled (159,602) $ 2.27   Unvested at September 30, 2017 761,813 $ 2.41 As of September 30, 2017 there was $ 1,487,756 of total unrecognized compensation cost related to unvested stock options, which is expected to be recognized over a weighted average vesting period of 2. 6 years. Summary of Restricted Stock Unit Transactions The Company began granting RSUs to employees in 2017. There were 62,300 RSUs granted with an aggregate fair value of $114,632 during the nine months ended September 30, 2017. The fair value of an RSU award is the closing price of the Company’s common stock on the date of grant. A summary of RSU activity for the nine months ended September 30, 2017 is as follows:    Number of RSUs Weighted Average Grant Date Fair Value  Outstanding, January 1, 2017 - $ -  Granted 62,300 $ 1.84  Vested and Released - $ -  Cancelled (15,000) $ 1.84   Outstanding, September 30, 2017 47,300 $ 1.84 As of September 30, 2017, there was $ 72,824 of total unrecognized compensation cost related to unvested RSUs which is expected to be recognized over a weighted average vesting period of 3. 4 years.

Warrants

Warrants	9 Months Ended
	Sep. 30, 2017
Warrants [Abstract]
Warrants	12. Warrants As of September 30, 2017 , warrants to pu rchase up to 5,288,466 share s were outstanding, having exercise prices ranging from $ 3.00 to $ 12. 80 and expiration dates ranging from December 4, 2017 to December 12, 20 22 .     2017 2016  Number of warrants Weighted average exercise price Number of warrants Weighted average exercise price  Balance, January 1 5,452,691 $ 4.92 2,649,199 $ 7.97  Issued during the period 1,696,970 $ 4.01 3,194,000 $ 3.47  Exercised during the period (1,861,195) $ 3.51 - $ -  Expired during the period - $ - (390,508) $ 13.72   Balance, September 30 5,288,466 $ 5.13 5,452,691 $ 4.92 At September 30, 2017 the weighted average remaining contractual life of the outstanding warrants was 3. 8 years.  The warrants issued to investors in the December 2012, November 2015, March 2016 and September 2016 offerings contain a provision for net cash settlement in the event of a fundamental transaction (contractually defined to include a merger, sale of substantially all assets, tender offer or share exchange). Pursuant to the November 2015, March 2016, and September 2016 warrants, if fundamental transaction occurs, then the warrant holder has the option to receive cash, equal to the fair value of the remaining unexercised portion of the warrant. The option is available to holders of the December 2012 warrants only if the consideration issued in the fundamental transaction consists of cash or stock in a non-public company. Due to these contingent redemption provisions, the warrants require liability classification in accordance with ASC 480, “Distinguishing Liabilities from Equity,” and are recorded at fair value. The June 2017 warrants contain a provision that allows the holder to opt for cash settlement in a fundamental transaction that was approved by, or required to be approved by, the board of directors of the Company. All of the Company’s outstanding warrants provide the holder the option as to the type of consideration received if the holders of common stock receive an option as to their consideration. In addition, all of the Company’s outstanding warrants contain a cashless exercise provision that is exercisable only in the event that a registration statement is not effective. That provision may not be operative if an effective registration statement is not available because an exemption under the U.S. securities laws may not be available to issue unregistered shares. As a result, net cash settlement may be required, and the warrants require liability classification.  ASC 820 , “Fair Value Measurements and Disclosures,” provides requirements for disclosure of liabilities that are measured at fair value on a recurring basis in periods subsequent to the initial recognition. Fair values for warrants were determined using the Binomial Lattice (“Lattice”) valuation technique. The Lattice model provides for dynamic assumptions regarding volatility and risk-free interest rates within the total period to maturity. Accordingly, within the contractual term, the Company provided multiple date intervals over which multiple volatilities and risk free interest rates were used. These intervals allow the Lattice model to project outcomes along specific paths that consider volatilities and risk free rates that would be more likely in an early exercise scenario.  Significant assumptions are determined as follows: Trading market values —Published trading market values; Exercise price —Stated exercise price; Term —Remaining contractual term of the warrant; Volatility —Historical trading volatility for periods consistent with the remaining terms; and Risk-free rate —Yields on zero coupon government securities with remaining terms consistent with the remaining terms of the warrants.  Due to the fundamental transaction provision, which could provide for early redemption of the warrants, the model also considered the probability the Company would enter into a fundamental transaction during the remaining term of the warrant. Because the Company is not yet achieving positive cash flow, management believes the probability of a fundamental transaction occurring over the term of the warrant is unlikely and therefore estimates the probability of entering into a fundamental transaction to be 5 %. For valuation purposes, the Company also assumed that if such a transaction did occur, it was more likely to occur towards the end of the term of the warrants.  The significant unobservable inputs used in the fair value measurement of the warrants include management’s estimate of the probability that a fundamental transaction may occur in the future. Significant increases (decreases) in the probability of occurrence would result in a significantly higher (lower) fair value measurement. The following table summarizes the fair value of the warrants as of the respective balance sheet dates:     Fair Value as of:  Warrant Issuance: September 30, 2017 December 31, 2016  December 2012 Investor Warrants $ 10 $ 49  July 2013 Investor Warrants 57,422 2,060  October 2013 Investor Warrants 106,316 3,708  January 2014 Investor Warrants 125,862 714  November 2015 Investor Warrants 1,564,850 260,500  November 2015 Placement Agent Warrants 3,882 13,542  March 2016 Investor Warrants 862,700 358,945  March 2016 Placement Agent Warrants - 21,320  September 2016 Investor Warrants 1,289,457 854,640  September 2016 Placement Agent Warrants - 57,888  June 2017 Investor Warrants 2,395,683 -  June 2017 Placement Agent Warrants 269,909 -  Total: $ 6,676,091 $ 1,573,366 The following table summarizes the number of shares indexed to the warrants as of the respective balance sheet dates:     Number of Shares indexed as of:  Warrant Issuance September 30, 2017 December 31, 2016  December 2012 Investor Warrants 17,430 17,430  July 2013 Investor Warrants 200,000 200,000  October 2013 Investor Warrants 231,732 231,732  January 2014 Investor Warrants 476,193 476,193  November 2015 Investor Warrants 1,250,001 1,250,001  November 2015 Placement Agent Warrants 3,334 83,335  March 2016 Investor Warrants 607,806 1,171,875  March 2016 Placement Agent Warrants - 78,125  September 2016 Investor Warrants 805,000 1,800,000  September 2016 Placement Agent Warrants - 144,000  June 2017 Investor Warrants 1,515,152 -  June 2017 Placement Agent Warrants 181,818 -  Total: 5,288,466 5,452,691 The assumptions used in calculating the fair values of the warrants are as follows:     September 30, 2017 December 31, 2016  Trading market prices $ 2.42 $ 1.40  Estimated future volatility 104 % 104 %  Dividend - -  Estimated future risk-free rate 1.06 -2.25 % 1.06 -2.44 %  Equivalent volatility 56-109 % 51-60 %  Equivalent risk-free rate 0.72 -1.52 % 0.59 -1.25 %    Changes in the fair value of the warrant liabili ties, carried at fair value, reported as “unrealized gain (loss) on fair value of warrants” in the statement of operations:     For the Three Months Ended September 30, For the Nine Months Ended September 30,  2017 2016 2017 2016  Expired Warrants $ - $ - $ - $ 2,590  December 2012 Investor Warrants 7,306 2,212 39 9,490  July 2013 Investor Warrants 125,686 22,040 (55,362) 115,940  October 2013 Investor Warrants 135,683 30,264 (102,608) 159,871  January 2014 Investor Warrants 177,900 12,190 (125,148) 129,905  November 2015 Investor Warrants 797,688 409,125 (1,304,350) 1,613,750  November 2015 Placement Agent Warrants 1,691 24,683 (366,694) 104,842  March 2016 Investor Warrants 356,472 425,625 (2,873,309) 1,677,891  March 2016 Placement Agent Warrants - 26,283 (351,899) 112,188  September 2016 Investor Warrants 506,353 12,780 (4,807,246) 12,780  September 2016 Placement Agent Warrants - 2,435 (503,150) 2,435  June 2017 Investor Warrants 894,076 - 1,277,485 -  June 2017 Placement Agent Warrants 117,645 - 164,411 -  Total: $ 3,120,500 $ 967,637 $ (9,047,831) $ 3,941,682 

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2017
Income Taxes [Abstract]
Income Taxes	13 . Income Taxes No provision for federal and state inc ome taxes was required for the three and nine months ended September 30, 2017 and 2016 due to the Company’s operating losses and increased deferred tax asset valuation allowance. At September 30, 2017 and December 31 , 2016, the Company had unused net operating loss carry-forwards of approxim ately $ 123,5 15,000 a nd $ 111,605 ,000 respectively, which expire at various dates through 203 7 . Some of this amount may be subject to annual limitations under certain provisions of the Internal Revenue Code related to “changes in ownership.” As of September 30, 2017 and December 31, 2016 , the deferred tax assets related to the aforementioned carry-forwards have been fully offset by valuation allowances, because significant utilization of such amounts is not presently expected in the foreseeable future. Deferred tax assets and valuation allowances consist of:     September 30, December 31,  2017 2016   Net Operating Loss Carryforwards $ 48,171,000 $ 43,526,000  Stock Compensation Expense 1,947,000 1,968,000  Book tax differences on assets and liabilities 425,000 547,000  Valuation Allowance (50,543,000) (46,041,000)   Net Deferred Tax Assets $ - $ - The Company files income tax returns in the U.S. federal and Maryland state jurisdictions. Tax years for fis cal 2014 through 2016 are open and potentially subject to examination by the federal and Maryland state taxing authorities.

Commitments And Contingencies

Commitments And Contingencies	9 Months Ended
	Sep. 30, 2017
Commitments And Contingencies [Abstract]
Commitments And Contingencies	14 . Commitments and Contingencies a) The Company has contracted with various vendors for services, with t erms that require payments over the terms of the agreements, usually ranging from two to 36 months. The costs to be incurred are estimated and are subject to revision. As of September 30, 2017, the total estimated cost to complete these agreements was approximately $ 10,75 0,000 . All of these agreements may be terminated by either party upon appropriate notice as stipulated in the respective agreements. b ) On June 22, 2009, the Company entered into a License Agreement with Korea Research Institute of Chemical Technology (“KRICT”) to acquire the rights to all inte llectual property related to quinoxaline-p iperazine derivatives that were synthesized under a Joint Research Agreement. The initial license fee was $ 100,000 , all of which was paid as of December 31, 2009. The agreement with KRICT calls for a one-time milestone payment of $ 1,000,000 within 30 days after the first achievement of marketing approval of the first commercial product arising out of or in connection with the use of KRICT’s intellectual property . As of September 30, 2017 , the milestone has not occurred. c ) Office Space Lease On June 5, 2009, the Company entered into a commercial lease agreement for 5,466 square feet of office space in Rockville, Maryland. The lease was amended on June 7, 2013 to extend the term until June 30, 2019. On July 26, 2014 the lease was amended to a dd 1,727 squ are feet of office space for a term beginning on September 1, 2014 and ending on August 31, 2015, which was subsequently renewed through June 30, 2019. Under the lease agreement, the Company pays its allocable portion of real estate taxes and common area operating charges. Rent paid under the Company’s lease during the three months ended September 30, 2017 and 2016 was $ 52,172 and $51 ,823 , respectively, and rent paid during the nine months ended September 30, 2017 and 2016 was $1 53,968 and 154,426 , respectively. Laboratory Lease On April 20, 2015, the Company signed a five -year lease agreement for 2,552 square feet of laboratory space commencing on July 1, 2015 and ending on June 30, 2020. Under the lease agreement, the Company pays its allocable portion of real estate taxes and common area operating charges. Rent paid under this lease during the three months ended September 30, 2017 and 2016 was $ 16,244 and $ 15,771 , respectively , and rent paid during the nine months ended September 30, 2017 and 2016 was $47,787 a nd $ 46,395 , respectively . Future rental payments over the next five years for all leases are as follows:    For the remaining three months ending December 31: 2017 $ 68,943  For the year ending December 31: 2018 279,274  2019 176,080  2020 34,468   Total $ 558,765   d ) The Company has established a 401(k) plan for its employees. The Company has elected to match 100% of the first 3% of an employee’s compensation plus 50% of an additional 2% of the employee’s deferral . Expense related to this matching contribution aggregated to $ 31,453 and $ 29,114 for the three months ended September 30 , 2 017 and 2016, respectively, and $ 102,536 and $92,203 for the nine months ended September 30, 2017 and 2016, respectively. e ) In July 2013, the Company entered into an exclusive license agreement with the University of Maryland, Baltimore for a novel drug delivery platform, Nano-Polymer Drug Conjugate Systems. RX-21101 is the Company’s first drug candidate utilizing this platform. The agreement requires the Company to make payments to the University of Maryland if RX-21101 or any products from the licensed delivery platform achieve development milestones. As of September 30, 2017, no development milestones have occurred. f) In October 2013, the Company signed an exclusive license agreement with the Ohio State Innovation Foundation, for a novel oligonucleotide drug delivery platform, Lipid-Coated Albumin Nanoparticle. The agreement requires the Company to make payments to the Ohio State Innovation Foundation if any products from the licensed delivery platform achieve development milestones. As of September 30, 2017, no development milestones have occurred.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2017
Fair Value Measurements [Abstract]
Fair Value Measurements	1 5 . Fair Value Measurements ASC 820 defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date, not adjusted for transaction costs. ASC 820 also establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value into three broad levels giving the highest priority to quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3).  The three levels are described below:  Level 1 Inputs — Unadjusted quoted prices in active markets for identical assets or liabilities that are accessible by the Company; Level 2 Inputs — Quoted prices in markets that are not active or financial instruments for which all significant inputs are observable, either directly or indirectly; and Level 3 Inputs — Unobservable inputs for the asset or liability including significant assumptions of the Company and other market participants. The following tables present assets and liabilities that are measured at fair value on a recurring basis and are categorized using the fair value hierarchy. There have been no changes in the methodologies used at September 30, 2017 and December 31, 2016. de    Fair Value Measurements at September 30, 2017  Total Level 1 Level 2 Level 3  Assets:  Commercial Paper 3,228,583 - 3,228,583 -  Corporate Bonds 11,748,763 - 11,748,763 -  Total Assets: $ 14,977,346 $ - $ 14,977,346 $ -   Liabilities:  Warrant Liabilities $ 6,676,091 $ - $ - $ 6,676,091     Fair Value Measurements at December 31, 2016  Total Level 1 Level 2 Level 3  Assets:  Certificates of Deposit $ 720,197 $ - $ 720,197 $ -  Commercial Paper 3,985,740 - 3,985,740 -  Corporate Bonds 4,031,170 - 4,031,170 -  Total Assets: $ 8,737,107 $ - $ 8,737,107 $ -   Liabilities:  Warrant Liabilities $ 1,573,366 $ - $ - $ 1,573,366  The fair value of the Company’s Level 2 marketable securities is determined by using quoted prices from independent pricing services that use market data for comparable securities in active or inactive markets. A variety of data inputs, including benchmark yields, interest rates, known historical trades and broker dealer quotes are used with pricing models to determine the quoted prices.  The fair value methodology for the warrant liabilities is disclosed in Note 1 2 .  The carrying amounts reported in the financial statements for cash and cash equivale nts (Level 1), approximate fair value because of the short term maturity of these financial instruments.  The following table sets forth a reconciliation of changes for the nine months ended September 30, 2017 and 2016 in the fair value of the liabilities classified as L evel 3 in the fair value hierarchy:      Warrant Liabilities  Balance at January 1, 2017 $ 1,573,366  Additions 4,107,488  Unrealized losses, net 9,047,831  Transfers out of level 3 (8,052,594)  Balance at September 30, 2017 $ 6,676,091     Warrant Liabilities  Balance at January 1, 2016 $ 2,739,163  Additions 4,364,110  Unrealized gains, net (3,941,682)  Transfers out of level 3 -  Balance at September 30, 2016 $ 3,161,591 Additions consist of the fair value of warrant liabilities up on issuance. Transfers out of L evel 3 for warrant liabilities consist of warrant exercises, where the liability is converted to additional paid-in capital upon exercise. The Company’s policy is to recognize transfers in and transfers out as of the actual date of the event or change in circumstance that caused the transfer.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2017
Subsequent Events [Abstract]
Subsequent Events	1 6 . Subsequent Events On October 17, 2017 the Company closed a registered direct public offering of 3,265,309 shares of common stock and warrants to purchase up to 1,632,654 shares of common stock. The common stock and warrants were sold in units, consisting of a share of common stock and a warrant to purchase 0.5 shares of common stock, at a price of $2.45 per unit, with an exercise price for the warrants of $2.85 per share . The total gross proceeds of the offering were $8,000,007 . The warrants issued will become exercisable beginning six months after the closing date, and will remain exercisable until the five-year anniversar y of the initial exercise date. The Company also issued warrants to purchase up to 195,919 shares of the Company’s common stock, at an exercise price of $3.06 per share, to designees of the placement agent in the offering.

Operations And Organization (Po

Operations And Organization (Policies)	9 Months Ended
	Sep. 30, 2017
Operations And Organization [Abstract]
Operations	Operations Rexahn Pharmaceuticals, Inc. (the “Company”), a Delaware corporation, is a biopharmaceutical company whose principal operations are the discovery, development and commercialization of innovative treatments for cancer. The Company had an accumulated deficit of $ 13 6,726,2 49 at September 30, 2017 and anticipates incurring losses through fiscal year 2017 and beyond. The Company has not yet generated commercial revenues and has funded its operating losses to date through the sale of shares of its common stock and warrants to purchase shares of its common stock, convertible debt, interest income from cash, cash equivalents and marketable securities, and proceeds from reimbursed research and development costs. The Company believes that its cash, cash equivalents, and marketable securities will be sufficient to cover its cash flow requirements for its current activities for at least the next 12 months from the date these financial statements were issued. Management believes it has the capability of managing the Company’s operations within existing cash available by focusing on select research and development activities, selecting projects in conjunction with potential financings and milestones, and efficiently managing the Company’s general and administrative affairs.
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed financial statements of the Company have been prepared pursuant to the rules and regulations of the U.S. Securities and Exchange Commission for interim financial information. Accordingly, they do not include all of the information and footnotes required by accounting principles generally accepted in the United States (“U.S. GAAP”) for complete financial statements. In the opinion of the Company’s management, all adjustments (consisting of only normal recurring accruals) considered necessary for a fair presentation of the Company’s financial position as of September 30, 2017 and December 31, 2016 and of the results of operations and comprehensive loss for the three and nine months ended September 30, 2017 and 2016 and cash flows for the nine months ended September 30, 2017 and 2016 have been included. Operating results for the three and nine months ended September 30, 2017 are not necessarily indicative of results that may be expected for any other interim period or the full fiscal year ending December 31, 2017. The accompanying unaudited condensed financial statements should be read in conjunction with the audited financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 (the “2016 Form 10-K”). Information included in the condensed balance sheet as of December 31, 2016 has been derived from the Company’s audited financial statements for the year ended December 31, 2016 included in the 2016 Form 10-K.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. These estimates are based on management’s best knowledge of current events and actions the Company may undertake in the future. Actual results may ultimately differ from these estimates. These estimates are reviewed periodically, and as adjustments become necessary, they are reported in earnings in the period in which they become available.

Recent Accounting Pronounceme24

Recent Accounting Pronouncements Affecting the Company (Policies)	9 Months Ended
	Sep. 30, 2017
Recent Accounting Pronouncements Affecting the Company [Abstract]
Recent Accounting Pronouncements Affecting the Company	Revenue from Contracts with Customers  In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-09, “Revenue from Contracts with Customers,” a comprehensive new revenue recognition standard that will supersede nearly all existing revenue recognition guidance under U.S. GAAP. The standard’s core principle is that a company should recognize revenue when it transfers goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods and services, and provides a revenue recognition framework in accordance with this principle. On August 12, 2015, the FASB issued ASU 2015-14, which defers the effective date of ASU 2014-09 by one year to December 15, 2017 for annual reporting periods beginning after that date and interim periods therein. The Company expects to adopt this standard for the annual reporting period beginning January 1, 2018. As the Company currently does not have revenue contracts, the Company does not expect the adoption of this standard to have a material impact on the operating results of the Company  Leases  In February 2016, the FASB issued ASU 2016-02, “Leases,” which requires an entity to recognize assets and liabilities arising from leases on the balance sheet and to provide additional disclosures about leasing arrangements. ASU 2016-02 will be effective for reporting periods beginning after December 15, 2018, with early adoption permitted. The Company is currently evaluating the impact the adoption of this guidance will have on its financial statements.  Compensation-Stock Compensation  In March 2016, the FASB issued ASU 2016-09, “Compensation-Stock Compensation: Improvements to Employee Share Based Payment Accounting,” which includes multiple provisions intended to simplify various aspects of accounting for share-based payments. The guidance is effective for reporting periods beginning after December 15, 2016, with early adoption permitted. The Company adopted this guidance for the three months ended March 31, 2017. This pronouncement did not have a material impact on the financial statements.

Marketable Securities (Tables)

Marketable Securities (Tables)	9 Months Ended
	Sep. 30, 2017
Marketable Securities [Abstract]
Schedule Of Cost And Fair Value Of Marketable Securities	  September 30, 2017  Cost Gross Unrealized Gross Unrealized Fair  Basis Gains Losses Value  Commercial Paper $ 3,230,566 $ - $ (1,983) $ 3,228,583  Corporate Bonds 11,760,745 142 (12,124) 11,748,763  Total Marketable Securities $ 14,991,311 $ 142 $ (14,107) $ 14,977,346   December 31, 2016  Cost Gross Unrealized Gross Unrealized Fair  Basis Gains Losses Value  Certificates of Deposit $ 720,000 $ 197 $ - $ 720,197  Commercial Paper 3,987,424 - (1,684) 3,985,740  Corporate Bonds 4,035,805 - (4,635) 4,031,170  Total Marketable Securities $ 8,743,229 $ 197 $ (6,319) $ 8,737,107 
Schedule Of Cost And Fair Value By Contractual Maturity	  Maturity Cost Basis Fair Value  Less than 1 year $ 11,963,973 $ 11,955,906  1 to 5 years 3,027,338 3,021,440  Total Marketable Securities $ 14,991,311 $ 14,977,346 

Prepaid Expenses And Other Cu26

Prepaid Expenses And Other Current Assets (Tables)	9 Months Ended
	Sep. 30, 2017
Prepaid Expenses And Other Current Assets [Abstract]
Schedule Of Prepaid Expenses And Other Current Assets	   September 30, December 31,  2017 2016   Deposits on contracts $ 611,550 $ 179,476  Prepaid expenses and other current assets 666,054 429,041   $ 1,277,604 $ 608,517 

Equipment, Net (Tables)

Equipment, Net (Tables)	9 Months Ended
	Sep. 30, 2017
Equipment, Net [Abstract]
Schedule Of Equipment, Net	   September 30, December 31,  2017 2016   Furniture and fixtures $ 78,794 $ 78,794  Office and computer equipment 121,817 113,932  Lab equipment 445,134 431,650  Leasehold improvements 133,762 133,762   Total equipment 779,507 758,138  Less: Accumulated depreciation and amortization (700,451) (669,488)   Net carrying amount $ 79,056 $ 88,650 

Accounts Payable And Accrued 28

Accounts Payable And Accrued Expenses (Tables)	9 Months Ended
	Sep. 30, 2017
Accounts Payable And Accrued Expenses [Abstract]
Schedule Of Accounts Payable And Accrued Expenses	   September 30, December 31,  2017 2016   Trade payables $ 462,602 $ 430,013  Accrued expenses 142,270 141,190  Accrued research and development contract costs 1,163,545 499,889  Payroll liabilities 570,360 811,408   $ 2,338,777 $ 1,882,500 

Other Liabilities (Tables)

Other Liabilities (Tables)	9 Months Ended
	Sep. 30, 2017
Other Liabilities [Abstract]
Schedule Of Deferred Lease Incentive	   September 30, December 31,  2017 2016   Deferred lease incentive $ 154,660 $ 154,660  Less accumulated amortization (132,884) (123,551)   Balance $ 21,776 $ 31,109 

Common Stock (Tables)

Common Stock (Tables)	9 Months Ended
	Sep. 30, 2017
Common Stock [Abstract]
Summary Of Allocation Of Proceeds From Offering	  Gross Proceeds: $ 10,000,003   Allocated to warrant liabilities 3,673,168  Allocated to common stock and additional paid-in capital 6,326,835   Total allocated gross proceeds: $ 10,000,003 

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2017
Stock-Based Compensation [Abstract]
Summary Of Stock Compensation Expense	  For the Three Months Ended September 30, For the Nine Months Ended September 30,  2017 2016 2017 2016  Statement of operations line item:  General and administrative $ 184,914 $ 232,951 $ 580,812 $ 673,064  Research and development 42,700 136,451 209,194 390,525   Total $ 227,614 $ 369,402 $ 790,006 $ 1,063,589 
Schedule Of Assumptions Made In Calculating The Fair Value Of Options	   Nine Months Ended September 30,  2017 2016  Black-Scholes assumptions  Expected dividend yield 0 % 0 %  Expected volatility 69-79 % 31-75 %  Risk free interest rate 1.8 -2.0 % 0.8 - 1.4 %  Expected term (in years) 5.5 -6 years 2 -6 years 
Summary Of Stock Options Outstanding	   Number of Options Weighted Average Exercise Price Weighted Average Remaining Contractual Term Aggregate Intrinsic Value  Outstanding, January 1, 2017 1,690,037 $ 6.20 7.3 years $ -  Granted 483,260 $ 2.37  Exercised (25,000) $ 3.10  Expired (15,000) $ 16.07  Cancelled (302,854) $ 5.00   Outstanding, September 30, 2017 1,830,443 $ 5.35 7.4 years $ 194,644  Exercisable, September 30, 2017 1,068,630 $ 6.60 6.3 years $ - 
Summary Of Unvested Shares	   2017  Number of Options Weighted Average Fair Value at Grant Date  Unvested at January 1, 2017 897,123 $ 3.21  Granted 483,260 $ 1.53  Vested (458,968) $ 3.12  Cancelled (159,602) $ 2.27   Unvested at September 30, 2017 761,813 $ 2.41 
Summary Of RSU Activity	  Number of RSUs Weighted Average Grant Date Fair Value  Outstanding, January 1, 2017 - $ -  Granted 62,300 $ 1.84  Vested and Released - $ -  Cancelled (15,000) $ 1.84   Outstanding, September 30, 2017 47,300 $ 1.84 

Warrants (Tables)

Warrants (Tables)	9 Months Ended
	Sep. 30, 2017
Warrants [Abstract]
Summary Of Changes In Warrants Outstanding During The Period	   2017 2016  Number of warrants Weighted average exercise price Number of warrants Weighted average exercise price  Balance, January 1 5,452,691 $ 4.92 2,649,199 $ 7.97  Issued during the period 1,696,970 $ 4.01 3,194,000 $ 3.47  Exercised during the period (1,861,195) $ 3.51 - $ -  Expired during the period - $ - (390,508) $ 13.72   Balance, September 30 5,288,466 $ 5.13 5,452,691 $ 4.92 
Schedule Of Fair Value Of Warrants Issued	   Fair Value as of:  Warrant Issuance: September 30, 2017 December 31, 2016  December 2012 Investor Warrants $ 10 $ 49  July 2013 Investor Warrants 57,422 2,060  October 2013 Investor Warrants 106,316 3,708  January 2014 Investor Warrants 125,862 714  November 2015 Investor Warrants 1,564,850 260,500  November 2015 Placement Agent Warrants 3,882 13,542  March 2016 Investor Warrants 862,700 358,945  March 2016 Placement Agent Warrants - 21,320  September 2016 Investor Warrants 1,289,457 854,640  September 2016 Placement Agent Warrants - 57,888  June 2017 Investor Warrants 2,395,683 -  June 2017 Placement Agent Warrants 269,909 -  Total: $ 6,676,091 $ 1,573,366 
Summary Of Shares Indexed To The Warrants	   Number of Shares indexed as of:  Warrant Issuance September 30, 2017 December 31, 2016  December 2012 Investor Warrants 17,430 17,430  July 2013 Investor Warrants 200,000 200,000  October 2013 Investor Warrants 231,732 231,732  January 2014 Investor Warrants 476,193 476,193  November 2015 Investor Warrants 1,250,001 1,250,001  November 2015 Placement Agent Warrants 3,334 83,335  March 2016 Investor Warrants 607,806 1,171,875  March 2016 Placement Agent Warrants - 78,125  September 2016 Investor Warrants 805,000 1,800,000  September 2016 Placement Agent Warrants - 144,000  June 2017 Investor Warrants 1,515,152 -  June 2017 Placement Agent Warrants 181,818 -  Total: 5,288,466 5,452,691 
Schedule Of Assumptions Used In Calculating Fair Value Of Warrants	   September 30, 2017 December 31, 2016  Trading market prices $ 2.42 $ 1.40  Estimated future volatility 104 % 104 %  Dividend - -  Estimated future risk-free rate 1.06 -2.25 % 1.06 -2.44 %  Equivalent volatility 56-109 % 51-60 %  Equivalent risk-free rate 0.72 -1.52 % 0.59 -1.25 % 
Schedule Of Unrealized Gain/(Loss) On Fair Value Of Warrants	  For the Three Months Ended September 30, For the Nine Months Ended September 30,  2017 2016 2017 2016  Expired Warrants $ - $ - $ - $ 2,590  December 2012 Investor Warrants 7,306 2,212 39 9,490  July 2013 Investor Warrants 125,686 22,040 (55,362) 115,940  October 2013 Investor Warrants 135,683 30,264 (102,608) 159,871  January 2014 Investor Warrants 177,900 12,190 (125,148) 129,905  November 2015 Investor Warrants 797,688 409,125 (1,304,350) 1,613,750  November 2015 Placement Agent Warrants 1,691 24,683 (366,694) 104,842  March 2016 Investor Warrants 356,472 425,625 (2,873,309) 1,677,891  March 2016 Placement Agent Warrants - 26,283 (351,899) 112,188  September 2016 Investor Warrants 506,353 12,780 (4,807,246) 12,780  September 2016 Placement Agent Warrants - 2,435 (503,150) 2,435  June 2017 Investor Warrants 894,076 - 1,277,485 -  June 2017 Placement Agent Warrants 117,645 - 164,411 -  Total: $ 3,120,500 $ 967,637 $ (9,047,831) $ 3,941,682 

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
	Sep. 30, 2017
Income Taxes [Abstract]
Schedule Of Deferred Tax Assets And Valuation Allowance	   September 30, December 31,  2017 2016   Net Operating Loss Carryforwards $ 48,171,000 $ 43,526,000  Stock Compensation Expense 1,947,000 1,968,000  Book tax differences on assets and liabilities 425,000 547,000  Valuation Allowance (50,543,000) (46,041,000)   Net Deferred Tax Assets $ - $ - 

Commitments And Contingencies (

Commitments And Contingencies (Tables)	9 Months Ended
	Sep. 30, 2017
Commitments And Contingencies [Abstract]
Schedule Of Future Rental Payments	   For the remaining three months ending December 31: 2017 $ 68,943  For the year ending December 31: 2018 279,274  2019 176,080  2020 34,468   Total $ 558,765 

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2017
Fair Value Measurements [Abstract]
Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis	   Fair Value Measurements at September 30, 2017  Total Level 1 Level 2 Level 3  Assets:  Commercial Paper 3,228,583 - 3,228,583 -  Corporate Bonds 11,748,763 - 11,748,763 -  Total Assets: $ 14,977,346 $ - $ 14,977,346 $ -   Liabilities:  Warrant Liabilities $ 6,676,091 $ - $ - $ 6,676,091     Fair Value Measurements at December 31, 2016  Total Level 1 Level 2 Level 3  Assets:  Certificates of Deposit $ 720,197 $ - $ 720,197 $ -  Commercial Paper 3,985,740 - 3,985,740 -  Corporate Bonds 4,031,170 - 4,031,170 -  Total Assets: $ 8,737,107 $ - $ 8,737,107 $ -   Liabilities:  Warrant Liabilities $ 1,573,366 $ - $ - $ 1,573,366 
Reconciliation Of Changes In The Fair Value Of Liabilities	   Warrant Liabilities  Balance at January 1, 2017 $ 1,573,366  Additions 4,107,488  Unrealized losses, net 9,047,831  Transfers out of level 3 (8,052,594)  Balance at September 30, 2017 $ 6,676,091     Warrant Liabilities  Balance at January 1, 2016 $ 2,739,163  Additions 4,364,110  Unrealized gains, net (3,941,682)  Transfers out of level 3 -  Balance at September 30, 2016 $ 3,161,591 

Operations And Organization (De

Operations And Organization (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Operations And Organization [Abstract]
Accumulated deficit	$ 136,726,249	$ 115,024,209

Marketable Securities (Narrativ

Marketable Securities (Narrative) (Details)	Sep. 30, 2017USD ($)item	Dec. 31, 2016USD ($)
Schedule of Available-for-sale Securities [Line Items]
Fair value	$ 14,977,346	$ 8,737,107
Unrealized losses	$ 14,107	$ 6,319
3 Commercial Paper With Unrealized Losses [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities in a loss position, less than one year | item	3
Fair value	$ 3,228,583
Unrealized losses	$ 1,983
11 Corporate Bond Securities With Unrealized Losses Less Than 12 Months [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities in a loss position, less than one year | item	11
Fair value	$ 11,249,968
Unrealized losses	$ 12,124

Marketable Securities (Schedule

Marketable Securities (Schedule Of Cost And Fair Value Of Marketable Securities) (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	$ 14,991,311	$ 8,743,229
Gross Unrealized Gains	142	197
Gross Unrealized Losses	(14,107)	(6,319)
Fair value	14,977,346	8,737,107
Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	3,230,566	3,987,424
Gross Unrealized Losses	(1,983)	(1,684)
Fair value	3,228,583	3,985,740
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	11,760,745	4,035,805
Gross Unrealized Gains	142
Gross Unrealized Losses	(12,124)	(4,635)
Fair value	$ 11,748,763	4,031,170
Certificates of Deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost Basis		720,000
Gross Unrealized Gains		197
Fair value		$ 720,197

Marketable Securities (Schedu39

Marketable Securities (Schedule Of Cost And Fair Value By Contractual Maturity) (Details)	Sep. 30, 2017USD ($)
Marketable Securities [Abstract]
Less than 1 year, Cost Basis, Maturity	$ 11,963,973
1 to 5 years, Cost Basis, Maturity	3,027,338
Total Marketable Securities, Cost Basis, Maturity	14,991,311
Less than 1 year, Fair Value, Maturity	11,955,906
1 to 5 years, Fair Value, Maturity	3,021,440
Total Marketable Securities, Fair Value, Maturity	$ 14,977,346

Prepaid Expenses And Other Cu40

Prepaid Expenses And Other Current Assets (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Prepaid Expenses And Other Current Assets [Abstract]
Deposits on contracts	$ 611,550	$ 179,476
Prepaid expenses and other current assets	666,054	429,041
Total prepaid expenses and other current assets	$ 1,277,604	$ 608,517

Equipment, Net (Details)

Equipment, Net (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Total equipment	$ 779,507	$ 758,138
Less: Accumulated depreciation and amortization	(700,451)	(669,488)
Net carrying amount	79,056	88,650
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Total equipment	78,794	78,794
Office And Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Total equipment	121,817	113,932
Lab Equipment [Member]
Property, Plant and Equipment [Line Items]
Total equipment	445,134	431,650
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Total equipment	$ 133,762	$ 133,762

Accounts Payable And Accrued 42

Accounts Payable And Accrued Expenses (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Accounts Payable And Accrued Expenses [Abstract]
Trade payables	$ 462,602	$ 430,013
Accrued expenses	142,270	141,190
Accrued research and development contract costs	1,163,545	499,889
Payroll liabilities	570,360	811,408
Total accounts payable and accrued expenses	$ 2,338,777	$ 1,882,500

Deferred Research And Develop43

Deferred Research And Development Arrangement (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2003	Dec. 31, 2016
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Deferred Research and Development Arrangement	$ 393,750		$ 393,750			$ 450,000
Rexgene Biotech Co., Ltd. [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development arrangement, one-time fee					$ 1,500,000
Reduction of research and development expenses	18,750	$ 18,750	$ 56,250	$ 56,250
Research and development period			20 years
Deferred Research and Development Arrangement	$ 393,750		$ 393,750			$ 450,000
Royalties paid, percentage of net sales			3.00%

Other Liabilities (Narrative) (

Other Liabilities (Narrative) (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Other Liabilities [Abstract]
Accrued Rent	$ 39,781	$ 48,095

Other Liabilities (Schedule Of

Other Liabilities (Schedule Of Deferred Lease Incentive) (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Other Liabilities [Abstract]
Deferred lease incentive	$ 154,660	$ 154,660
Less accumulated amortization	(132,884)	(123,551)
Balance	$ 21,776	$ 31,109

Net Loss Per Common Share (Deta

Net Loss Per Common Share (Details) - shares	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Net Loss Per Common Share [Abstract]
Potentially dilutive securities	7,166,209	7,142,728

Common Stock (Narrative) (Detai

Common Stock (Narrative) (Details)	Jun. 12, 2017USD ($)$ / sharesshares	May 05, 2017$ / sharesshares	Sep. 30, 2017USD ($)$ / sharesshares	Sep. 30, 2016shares	Dec. 31, 2016$ / shares
Class of Stock [Line Items]
Reverse stock split		0.1
Common stock, par value | $ / shares			$ 0.0001		$ 0.0001
Cash paid for warrants exercised			$ 5,354,093
Shares issued for warrants exercised | shares			1,652,623
Stock options exercised			$ 77,500
Stock options exercised, shares | shares			25,000
Shares issued | shares	3,030,304
Number of warrants, issued | shares	1,515,152		1,696,970	3,194,000
Warrants issued per share of stock issued in unit offering | $ / shares	$ 0.5
Share Price | $ / shares	3.30
Stock Warrants, Exercise Price | $ / shares	$ 4
Proceeds from issuance	$ 10,000,003
Warrants issued included in closing costs | shares	181,818
Public offering closing costs	$ 1,193,052
Fair value of placement agent warrants	434,320
Cash paid in exchange for closing costs	758,732
Proceeds allocated to financing expense	333,050
Issuance cost incurred	$ 860,002
Stock issued for services | shares			15,000
Aggregate market value			$ 31,200
Common Stock [Member]
Class of Stock [Line Items]
Common stock, par value | $ / shares		$ 0.0001
Shares authorized | shares		50,000,000
Preferred Stock [Member]
Class of Stock [Line Items]
Shares authorized | shares		10,000,000

Common Stock (Summary Of Alloca

Common Stock (Summary Of Allocation Of Proceeds From Offering) (Details)	Jun. 12, 2017USD ($)
Common Stock [Abstract]
Allocated to warrant liabilities	$ 3,673,168
Allocated to Common stock and additional paid-in capital	6,326,835
Gross Proceeds:	$ 10,000,003

Stock-Based Compensation (Narra

Stock-Based Compensation (Narrative) (Details) - USD ($)	Apr. 11, 2017	Mar. 31, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Jun. 10, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding			1,830,443		1,830,443
Number of RSUs outstanding			47,300		47,300
Share-based compensation expense			$ 227,614	$ 369,402	$ 790,006	$ 1,063,589
Income tax benefit from share-based compensation					$ 0
Valuation allowance on deferred tax assets					100.00%
Options exercised					25,000
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding			1,830,443		1,830,443		1,690,037
Vesting period					4 years
Percentage of Event Occurence to Vest					100.00%
Stock options granted					483,260
Stock option exercise price					$ 2.37
Intrinsic value of options exercised			$ 0	$ 0	$ 97,872	$ 0
Options exercised					25,000
Weighted average fair value at grant date, Vested					$ 1.53	$ 1.96
Unrecognized compensation cost			$ 1,487,756		$ 1,487,756
Weighted average vesting period, years					2 years 7 months 6 days
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSUs outstanding			47,300		47,300
Number of shares granted					62,300
Aggregate fair value					$ 114,632
Unrecognized compensation cost			$ 72,824		$ 72,824
Weighted average vesting period, years					3 years 4 months 24 days
March 2016 [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration of options from grant date, years					3 years
The 2013 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options authorized for issuance								1,700,000
Additional options authorized for issuance	1,700,000
Shares available for issuance			1,868,507		1,868,507
The 2013 Plan [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding			1,483,443		1,483,443
The 2013 Plan [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSUs outstanding			47,300		47,300
The 2003 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding			335,000		335,000
First Anniversary [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					30.00%
Second Anniversary [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					30.00%
Third Anniversary [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					40.00%
First Anniversary (B) [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					25.00%
Second Anniversary (B) [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					25.00%
Third Anniversary (B) [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					25.00%
Fourth Anniversary (B) [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					25.00%
Minimum [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period					1 year
Maximum [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period					3 years
Expiration of options from grant date, years					10 years
Exercise Price Range $1.84 to $6.18 [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted					483,260
Stock option grants fair value					$ 738,937
Exercise Price Range $1.84 to $6.18 [Member] | Minimum [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option exercise price					$ 1.84
Exercise Price Range $1.84 to $6.18 [Member] | Maximum [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option exercise price					$ 6.18
Exercise Price Range $2.60 to $3.70 [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted						587,637
Stock option grants fair value						$ 1,150,513
Exercise Price Range $2.60 to $3.70 [Member] | Minimum [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option exercise price						$ 2.60
Exercise Price Range $2.60 to $3.70 [Member] | Maximum [Member] | Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option exercise price						$ 3.70
Third Party [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted		12,000

Stock-Based Compensation (Summa

Stock-Based Compensation (Summary Of Stock Compensation Expense) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share Based Compensation	$ 227,614	$ 369,402	$ 790,006	$ 1,063,589
General and administrative [Member]
Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share Based Compensation	184,914	232,951	580,812	673,064
Research and development [Member]
Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share Based Compensation	$ 42,700	$ 136,451	$ 209,194	$ 390,525

Stock-Based Compensation (Sched

Stock-Based Compensation (Schedule Of Assumptions Made In Calculating The Fair Value Of Options) (Details) - Stock Option [Member]	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Expected dividend yield	0.00%	0.00%
Expected volatility, minimum	69.00%	31.00%
Expected volatility, maximum	79.00%	75.00%
Risk free interest rate, minimum	1.80%	0.80%
Risk free interest rate, maximum	2.00%	1.40%
Minimum [Member]
Expected term (in years)	5 years 6 months	2 years
Maximum [Member]
Expected term (in years)	6 years	6 years

Stock-Based Compensation (Sum52

Stock-Based Compensation (Summary Of Stock Options Outstanding) (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Number of options, Exercised	(25,000)
Number of options, Oustanding	1,830,443
Stock Option [Member]
Number of options, Oustanding	1,690,037
Number of Options, Granted	483,260
Number of options, Exercised	(25,000)
Number of options, Expired	(15,000)
Number of options, Cancelled	(302,854)
Number of options, Oustanding	1,830,443	1,690,037
Weighted average exercise price, Outstanding	$ 6.20
Weighted average exercise price, Granted	2.37
Weighted average exercise price, Exercised	3.10
Weighted average exercise price, Expired	16.07
Weighted average exercise price, Cancelled	5
Weighted average exercise price, Outstanding	$ 5.35	$ 6.20
Weighted average remaining contractual term, Outstanding	7 years 4 months 24 days	7 years 3 months 18 days
Aggregate intrinsic value, Outstanding	$ 194,644
Number of options, Exercisable	1,068,630
Weighted average exercise price, Exercisable	$ 6.60
Weighted average remaining contractual term, Exercisable	6 years 3 months 18 days
Aggregate intrinsic value, Exercisable

Stock-Based Compensation (Sum53

Stock-Based Compensation (Summary Of Unvested Shares) (Details) - Stock Option [Member]	9 Months Ended
	Sep. 30, 2017$ / sharesshares
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Number of Options, Unvested | shares	897,123
Number of Options, Granted | shares	483,260
Number of Options, Vested | shares	(458,968)
Number of Options, Cancelled | shares	(159,602)
Number of Options, Unvested | shares	761,813
Weighted Average Fair Value at Grant Date, Unvested | $ / shares	$ 3.21
Weighted Average Fair Value at Grant Date, Granted | $ / shares	1.53
Weighted Average Fair Value at Grant Date, Vested | $ / shares	3.12
Weighted Average Fair Value at Grant Date, Cancelled | $ / shares	2.27
Weighted Average Fair Value at Grant Date, Unvested | $ / shares	$ 2.41

Stock-Based Compensation (Sum54

Stock-Based Compensation (Summary Of RSU Activity) (Details)	9 Months Ended
	Sep. 30, 2017$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSUs, Outstanding	47,300
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSUs, Outstanding
Number of RSUs, Granted	62,300
Number of RSUs, Vested and Released
Number of RSUs, Cancelled	(15,000)
Number of RSUs, Outstanding	47,300
Weighted Average Grant Date Fair Value, Outstanding | $ / shares
Weighted Average Grant Date Fair Value, Granted | $ / shares	1.84
Weighted Average Grant Date Fair Value, Vested and Released | $ / shares
Weighted Average Grant Date Fair Value, Cancelled | $ / shares	1.84
Weighted Average Grant Date Fair Value, Outstanding | $ / shares	$ 1.84

Warrants (Narrative) (Details)

Warrants (Narrative) (Details) - $ / shares	9 Months Ended
	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015
Class of Warrant or Right [Line Items]
Number of warrants, Outstanding	5,288,466	5,452,691	5,452,691	2,649,199
Exercise price	$ 5.13	$ 4.92	$ 4.92	$ 7.97
Warrant expiration date, start	Dec. 4, 2017
Warrant expiration date, end	Dec. 12, 2022
Average remaining contractual life of warrants outstanding	3 years 9 months 18 days
Probability of entering into a fundamental transaction	5.00%
Maximum [Member]
Class of Warrant or Right [Line Items]
Exercise price	$ 12.80
Minimum [Member]
Class of Warrant or Right [Line Items]
Exercise price	$ 3

Warrants (Summary Of Changes In

Warrants (Summary Of Changes In Warrants Outstanding During The Period) (Details) - $ / shares	Jun. 12, 2017	Sep. 30, 2017	Sep. 30, 2016
Warrants [Abstract]
Number of warrants, Outstanding		5,452,691	2,649,199
Weigted average exercise price, Outstanding		$ 4.92	$ 7.97
Number of warrants, issued	1,515,152	1,696,970	3,194,000
Weighted average exercise price, Issued		$ 4.01	$ 3.47
Number of warrants, Exercised		(1,861,195)
Weighted average exercise price, Exercised		$ 3.51
Number of warrants, Expired			(390,508)
Weighted average exercise price, Expired			$ 13.72
Number of warrants, Outstanding		5,288,466	5,452,691
Weigted average exercise price, Outstanding		$ 5.13	$ 4.92

Warrants (Schedule Of Fair Valu

Warrants (Schedule Of Fair Value Of Warrants Issued) (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Class of Warrant or Right [Line Items]
Fair value	$ 6,676,091	$ 1,573,366
December 2012 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Fair value	10	49
July 2013 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Fair value	57,422	2,060
October 2013 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Fair value	106,316	3,708
January 2014 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Fair value	125,862	714
November 2015 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Fair value	1,564,850	260,500
November 2015 Placement Agent Warrants [Member]
Class of Warrant or Right [Line Items]
Fair value	3,882	13,542
March 2016 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Fair value	862,700	358,945
March 2016 Placement Agent Warrants [Member]
Class of Warrant or Right [Line Items]
Fair value		21,320
September 2016 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Fair value	1,289,457	854,640
September 2016 Placement Agent Warrants [Member]
Class of Warrant or Right [Line Items]
Fair value		$ 57,888
June 2017 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Fair value	2,395,683
June 2017 Placement Agent Warrants [Member]
Class of Warrant or Right [Line Items]
Fair value	$ 269,909

Warrants (Summary Of Shares Ind

Warrants (Summary Of Shares Indexed To The Warrants) (Details) - shares	Sep. 30, 2017	Dec. 31, 2016
Class of Warrant or Right [Line Items]
Number of shares indexed	5,288,466	5,452,691
December 2012 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Number of shares indexed	17,430	17,430
July 2013 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Number of shares indexed	200,000	200,000
October 2013 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Number of shares indexed	231,732	231,732
January 2014 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Number of shares indexed	476,193	476,193
November 2015 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Number of shares indexed	1,250,001	1,250,001
November 2015 Placement Agent Warrants [Member]
Class of Warrant or Right [Line Items]
Number of shares indexed	3,334	83,335
March 2016 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Number of shares indexed	607,806	1,171,875
March 2016 Placement Agent Warrants [Member]
Class of Warrant or Right [Line Items]
Number of shares indexed		78,125
September 2016 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Number of shares indexed	805,000	1,800,000
September 2016 Placement Agent Warrants [Member]
Class of Warrant or Right [Line Items]
Number of shares indexed		144,000
June 2017 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Number of shares indexed	1,515,152
June 2017 Placement Agent Warrants [Member]
Class of Warrant or Right [Line Items]
Number of shares indexed	181,818

Warrants (Schedule Of Assumptio

Warrants (Schedule Of Assumptions Used In Calculating Fair Value Of Warrants) (Details) - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Class of Warrant or Right [Line Items]
Trading market prices	$ 2.42	$ 1.40
Estimated future volatility	104.00%	104.00%
Dividend
Minimum [Member]
Class of Warrant or Right [Line Items]
Estimated future risk-free rate	1.06%	1.06%
Equivalent volatility	56.00%	51.00%
Equivalent risk-free rate	0.72%	0.59%
Maximum [Member]
Class of Warrant or Right [Line Items]
Estimated future risk-free rate	2.25%	2.44%
Equivalent volatility	109.00%	60.00%
Equivalent risk-free rate	1.52%	1.25%

Warrants (Schedule Of Unrealize

Warrants (Schedule Of Unrealized Gain/(Loss) On Fair Value Of Warrants) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Class of Warrant or Right [Line Items]
Unrealized gain (loss) on fair value of warrants	$ 3,120,500	$ 967,637	$ (9,047,831)	$ 3,941,682
Expired Warrants [Member]
Class of Warrant or Right [Line Items]
Unrealized gain (loss) on fair value of warrants				2,590
December 2012 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Unrealized gain (loss) on fair value of warrants	7,306	2,212	39	9,490
July 2013 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Unrealized gain (loss) on fair value of warrants	125,686	22,040	(55,362)	115,940
October 2013 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Unrealized gain (loss) on fair value of warrants	135,683	30,264	(102,608)	159,871
January 2014 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Unrealized gain (loss) on fair value of warrants	177,900	12,190	(125,148)	129,905
November 2015 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Unrealized gain (loss) on fair value of warrants	797,688	409,125	(1,304,350)	1,613,750
November 2015 Placement Agent Warrants [Member]
Class of Warrant or Right [Line Items]
Unrealized gain (loss) on fair value of warrants	1,691	24,683	(366,694)	104,842
March 2016 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Unrealized gain (loss) on fair value of warrants	356,472	425,625	(2,873,309)	1,677,891
March 2016 Placement Agent Warrants [Member]
Class of Warrant or Right [Line Items]
Unrealized gain (loss) on fair value of warrants		26,283	(351,899)	112,188
September 2016 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Unrealized gain (loss) on fair value of warrants	506,353	12,780	(4,807,246)	12,780
September 2016 Placement Agent Warrants [Member]
Class of Warrant or Right [Line Items]
Unrealized gain (loss) on fair value of warrants		$ 2,435	(503,150)	$ 2,435
June 2017 Investor Warrants [Member]
Class of Warrant or Right [Line Items]
Unrealized gain (loss) on fair value of warrants	894,076		1,277,485
June 2017 Placement Agent Warrants [Member]
Class of Warrant or Right [Line Items]
Unrealized gain (loss) on fair value of warrants	$ 117,645		$ 164,411

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Operating Loss Carryforwards [Line Items]
Provision for income taxes
Operating loss carry-forward	123,515,000		$ 123,515,000		$ 111,605,000
Net operating loss carry-forwards expiration			Dec. 31, 2037
Federal And State [Member]
Operating Loss Carryforwards [Line Items]
Provision for income taxes	$ 0	$ 0	$ 0	$ 0

Income Taxes (Schedule Of Defer

Income Taxes (Schedule Of Deferred Tax Assets And Valuation Allowance) (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Income Taxes [Abstract]
Net Operating Loss Carryforwards	$ 48,171,000	$ 43,526,000
Stock Compensation Expense	1,947,000	1,968,000
Book tax differences on assets and liabilities	425,000	547,000
Valuation Allowance	(50,543,000)	(46,041,000)
Net Deferred Tax Assets

Commitments And Contingencies63

Commitments And Contingencies (Narrative) (Details)	Apr. 20, 2015ft²	Jul. 26, 2014ft²	Jun. 07, 2013ft²	Jun. 22, 2009USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)	Dec. 31, 2009USD ($)
Commitments And Contingencies [Line Items]
Estimated cost to complete contracts					$ 10,750,000		$ 10,750,000
License Costs									$ 100,000
One-time milestone payment				$ 1,000,000
Employer matching contribution							100.00%
Maximum percentage of employee's gross pay							3.00%
Employer matching contribution on deferral							50.00%
Percentage of employee's gross pay							2.00%
Expense related to matching contribution					31,453	$ 29,114	$ 102,536	$ 92,203
Maximum [Member]
Commitments And Contingencies [Line Items]
Contract term, months							36 months
Minimum [Member]
Commitments And Contingencies [Line Items]
Contract term, months							2 months
Current Laboratory Lease [Member]
Commitments And Contingencies [Line Items]
Lease term							5 years
Size of lease space | ft²	2,552
Rent expense					16,244	15,771	$ 47,787	46,395
Office Space Rental [Member]
Commitments And Contingencies [Line Items]
Size of lease space | ft²			5,466
Additional office space | ft²		1,727
Rent expense					$ 52,172	$ 51,823	$ 153,968	$ 154,426

Commitments and Contingencies64

Commitments and Contingencies (Schedule Of Future Rental Payments) (Details)	Sep. 30, 2017USD ($)
Commitments And Contingencies [Abstract]
2,017	$ 68,943
2,018	279,274
2,019	176,080
2,020	34,468
Total	$ 558,765

Fair Value Measurements (Schedu

Fair Value Measurements (Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets:	$ 14,977,346	$ 8,737,107
Warrant Liabilities	6,676,091	1,573,366
Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets:	11,748,763	4,031,170
Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets:		720,197
Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets:	3,228,583	3,985,740
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets:	14,977,346	8,737,107
Level 2 [Member] | Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets:	11,748,763	4,031,170
Level 2 [Member] | Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets:		720,197
Level 2 [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets:	3,228,583	3,985,740
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Warrant Liabilities	$ 6,676,091	$ 1,573,366

Fair Value Measurements (Reconc

Fair Value Measurements (Reconciliation Of Changes In The Fair Value Of Liabilities) (Details) - Warrant Liabilities [Member] - USD ($)	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance	$ 1,573,366	$ 2,739,163
Additions	4,107,488	4,364,110
Unrealized (gains) losses, net	9,047,831	(3,941,682)
Transfers out of level 3	(8,052,594)
Balance	$ 6,676,091	$ 3,161,591

Subsequent Events (Details)

Subsequent Events (Details) - USD ($)	Oct. 17, 2017	Jun. 12, 2017	Sep. 30, 2017	Sep. 30, 2016
Subsequent Event [Line Items]
Shares issued		3,030,304
Warrants issued		1,515,152	1,696,970	3,194,000
Warrants issued per share of stock issued in unit offering		$ 0.5
Share Price		3.30
Stock Warrants, Exercise Price		$ 4
Proceeds from issuance		$ 10,000,003
Warrants issued included in closing costs		181,818
Subsequent Event [Member]
Subsequent Event [Line Items]
Shares issued	3,265,309
Warrants issued	1,632,654
Warrants issued per share of stock issued in unit offering	$ 0.5
Share Price	2.45
Stock Warrants, Exercise Price	$ 2.85
Proceeds from issuance	$ 8,000,007
Warrants issued included in closing costs	195,919
Warrants issued included in closing costs, exercise price	$ 3.06