CervoMed (CRVO) 10-Q 8 Aug 23 2023 Q2 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2023	Aug. 07, 2023
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2023
Document Transition Report	false
Entity File Number	001-37942
Entity Registrant Name	DIFFUSION PHARMACEUTICALS INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	30-0645032
Entity Address, Address Line One	300 East Main Street, Suite 101
Entity Address, City or Town	Charlottesville
Entity Address, State or Province	VA
Entity Address, Postal Zip Code	22902
City Area Code	434
Local Phone Number	220-0718
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	DFFN
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		2,040,287
Entity Central Index Key	0001053691
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
Amendment Flag	false

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($)	Jun. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 14,999,548	$ 10,113,706
Marketable securities	0	12,408,940
Prepaid expenses, deposits and other current assets	695,070	112,406
Assets	15,694,618	22,635,052
Current liabilities:
Accounts payable	932,427	1,127,782
Accrued expenses and other current liabilities	532,550	1,289,554
Total liabilities	1,464,977	2,417,336
Commitments and Contingencies
Stockholders’ Equity:
Common stock, $0.001 par value: 1,000,000,000 shares authorized: 2,040,287 and 2,039,557 shares issued and outstanding at June 30, 2023 and December 31, 2022, respectively	2,040	2,040
Additional paid-in capital	166,029,626	165,847,590
Accumulated other comprehensive loss	0	(35,375)
Accumulated deficit	(151,802,025)	(145,596,539)
Total stockholders' equity	14,229,641	20,217,716
Total liabilities and stockholders' equity	$ 15,694,618	$ 22,635,052

Consolidated Balance Sheets (_2

Consolidated Balance Sheets (Unaudited) (Parentheticals) - $ / shares	Jun. 30, 2023	Dec. 31, 2022
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001	$ 0.001
Common Stock, Shares Authorized (in shares)	1,000,000,000	1,000,000,000
Common Stock, Shares, Outstanding (in shares)	2,040,287	2,039,557
Common Stock, Shares, Issued (in shares)	2,040,287	2,039,557

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Operating expenses:
Research and development	$ 72,185	$ 2,108,553	$ 1,380,774	$ 4,534,451
General and administrative	2,220,373	2,137,326	5,178,065	4,265,878
Loss from operations	2,292,558	4,245,879	6,558,839	8,800,329
Interest income	(179,456)	(55,378)	(353,353)	(83,187)
Net loss	$ (2,113,102)	$ (4,190,501)	$ (6,205,486)	$ (8,717,142)
Per share information:
Net loss per share of common stock, basic and diluted (in dollars per share)	$ (1.04)	$ (2.06)	$ (3.04)	$ (4.28)
Weighted average shares outstanding, basic and diluted (in shares)	2,040,066	2,038,727	2,039,902	2,038,529
Comprehensive loss:
Net loss	$ (2,113,102)	$ (4,190,501)	$ (6,205,486)	$ (8,717,142)
Unrealized gain (loss) on marketable securities	3,123	(36,925)	35,375	(86,583)
Comprehensive loss	$ (2,109,979)	$ (4,227,426)	$ (6,170,111)	$ (8,803,725)

Consolidated Statements of Chan

Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($)	Common Stock [Member]	Preferred Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance at January 1, 2023 (in shares) at Dec. 31, 2021	2,038,185	0
Balance at January 1, 2023 at Dec. 31, 2021	$ 2,038	$ 0	$ 164,914,540	$ 0	$ (130,005,111)	$ 34,911,467
Stock-based compensation expense and vesting of restricted stock units (in shares)	529
Stock-based compensation expense and vesting of restricted stock units			556,261			556,261
Unrealized gain (loss) on marketable securities	$ 0	0	0	(86,583)	0	(86,583)
Net loss	$ 0	$ 0	0	0	(8,717,142)	(8,717,142)
Conversion of Stock, Shares Converted (in shares)		(10,000)
Conversion of Stock, Amount Converted		$ (5,000)
Conversion of Stock, Shares Issued (in shares)	200
Unrealized loss on marketable securities	$ 0	$ 0	0	(86,583)	0	(86,583)
Sale of series C preferred stock to related parties (in shares)	0	10,000
Sale of series C preferred stock to related parties	$ 0	$ 5,000	0	0	0	5,000
Balance at March 31, 2023 (in shares) at Jun. 30, 2022	2,038,914	0
Balance at March 31, 2023 at Jun. 30, 2022	$ 2,038	$ 0	165,475,801	(86,583)	(138,722,253)	26,669,003
Balance at January 1, 2023 (in shares) at Mar. 31, 2022	2,038,392	10,000
Balance at January 1, 2023 at Mar. 31, 2022	$ 2,038	$ 5,000	165,192,671	(49,658)	(134,531,752)	30,618,299
Stock-based compensation expense and vesting of restricted stock units (in shares)	322
Stock-based compensation expense and vesting of restricted stock units			278,130			278,130
Unrealized gain (loss) on marketable securities	$ 0	0	0	(36,925)	0	(36,925)
Net loss	$ 0	$ 0	0	0	(4,190,501)	(4,190,501)
Conversion of Stock, Shares Converted (in shares)		(10,000)
Conversion of Stock, Amount Converted		$ (5,000)
Conversion of Stock, Shares Issued (in shares)	200
Unrealized loss on marketable securities	$ 0	$ 0	0	(36,925)	0	(36,925)
Balance at March 31, 2023 (in shares) at Jun. 30, 2022	2,038,914	0
Balance at March 31, 2023 at Jun. 30, 2022	$ 2,038	$ 0	165,475,801	(86,583)	(138,722,253)	26,669,003
Additional Paid in Capital, Preferred Stock			5,000
Balance at January 1, 2023 (in shares) at Dec. 31, 2022	2,039,557
Balance at January 1, 2023 at Dec. 31, 2022	$ 2,040		165,847,590	(35,375)	(145,596,539)	20,217,716
Stock-based compensation expense and vesting of restricted stock units (in shares)	730
Stock-based compensation expense and vesting of restricted stock units			182,036			182,036
Unrealized gain (loss) on marketable securities	$ 0		0	35,375	0	35,375
Net loss	0		0	0	(6,205,486)	(6,205,486)
Unrealized loss on marketable securities	$ 0		0	35,375	0	35,375
Balance at March 31, 2023 (in shares) at Jun. 30, 2023	2,040,287
Balance at March 31, 2023 at Jun. 30, 2023	$ 2,040		166,029,626	0	(151,802,025)	14,229,641
Balance at January 1, 2023 (in shares) at Mar. 31, 2023	2,040,025
Balance at January 1, 2023 at Mar. 31, 2023	$ 2,040		165,968,961	(3,123)	(149,688,923)	16,278,955
Stock-based compensation expense and vesting of restricted stock units (in shares)	262
Stock-based compensation expense and vesting of restricted stock units			60,665			60,665
Unrealized gain (loss) on marketable securities	$ 0		0	3,123	0	3,123
Net loss	0		0	0	(2,113,102)	(2,113,102)
Unrealized loss on marketable securities	$ 0		0	3,123	0	3,123
Balance at March 31, 2023 (in shares) at Jun. 30, 2023	2,040,287
Balance at March 31, 2023 at Jun. 30, 2023	$ 2,040		$ 166,029,626	$ 0	$ (151,802,025)	$ 14,229,641

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($)	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Cash flows from operating activities:
Net loss	$ (6,205,486)	$ (8,717,142)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	182,036	556,261
Amortization of premium and discount on marketable securities	55,685	45,439
Changes in operating assets and liabilities:
Prepaid expenses, deposits and other assets	(582,664)	(118,025)
Accounts payable, accrued expenses and other liabilities	(952,359)	(412,662)
Net cash used in operating activities	(7,614,158)	(8,737,007)
Cash flows from investing activities:
Purchases of marketable securities	0	(31,615,825)
Maturities of marketable securities	12,500,000	9,000,000
Net cash provided by (used in) investing activities	12,500,000	(22,615,825)
Cash flows from financing activities:
Proceeds from the sale of series C preferred stock to related parties	0	5,000
Net cash provided by financing activities	0	5,000
Net increase (decrease) in cash and cash equivalents	4,885,842	(31,347,832)
Cash and cash equivalents at beginning of period	10,113,706	37,313,558
Cash and cash equivalents at end of period	14,999,548	5,965,726
Supplemental disclosure of non-cash investing and financing activities:
Unrealized gain (loss) on marketable securities	$ 0	$ (86,583)

Note 1 - Organization and Descr

Note 1 - Organization and Description of Business	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Nature of Operations [Text Block]	1. Organization and Description of Business Diffusion Pharmaceuticals Inc., a Delaware corporation, is a biopharmaceutical company that has historically focused on developing novel therapies that may enhance the body’s ability to deliver oxygen to areas where it is needed most. The Company’s most advanced product candidate, TSC, has been investigated and developed to enhance the diffusion of oxygen to tissues with low oxygen levels, also known as hypoxia, most recently as an adjuvant treatment to standard of care therapy for GBM and other hypoxic solid tumors. On March 30, 2023, Diffusion, Merger Sub and EIP entered into the Merger Agreement, pursuant to which, among other things, subject to the satisfaction or waiver of the conditions set forth in the Merger Agreement, Merger Sub will merge with and into EIP, with EIP surviving the merger as the wholly-owned subsidiary of the combined company. Diffusion has called a special meeting of stockholders currently scheduled for August 15, 2023 in order to obtain the stockholder approvals necessary to complete the Merger and certain related transactions, as more fully described in the Merger Proxy Statement.

Note 2 - Liquidity

Note 2 - Liquidity	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Liquidity Disclosure [Text Block]	2. Liquidity The Company has not generated any revenues from product sales and has historically funded operations primarily from the proceeds of public and private offerings of equity, convertible debt, and convertible preferred stock. On March 30, 2023, the Company entered into the Merger Agreement with EIP and Merger Sub, pursuant to which, and subject to the satisfaction or waiver of the conditions set forth therein, Merger Sub will be merged with and into EIP at the effective time of the Merger, with EIP continuing after the Merger as the surviving corporation and a wholly-owned subsidiary of the Company. Diffusion has called a special meeting of stockholders currently scheduled for August 15, 2023 in order to obtain the stockholder approvals necessary to complete the Merger and certain related transactions, as more fully described in the Merger Proxy Statement. The Merger is intended to qualify as a tax-free reorganization for U.S. federal income tax purposes. In connection with the Merger Agreement with EIP and efforts to utilize and preserve assets in a manner that maximizes value for its stockholders, the Company committed to a reduction in force in the first quarter of 2023 that impacted seven of the Company’s thirteen employees. The reduction was a cash preservation measure and impacted employees primarily in the Company’s clinical operations function. The Company has paused significant portions of its TSC development activities in the first quarter of 2023, including initiation of the Company’s previously announced Phase 2 study of TSC in newly diagnosed GBM patients. Substantial additional financing will be required by the Company to fund any research and development activities related to the Company's existing or future product candidates, including EIP's product candidates if the Merger is closed. The Company regularly explores alternative means of financing its operations and seeks funding through various sources, including public and private securities offerings, collaborative arrangements with third parties, and other strategic alliances and business transactions. However, as of the date of this Quarterly Report, the Company does not have any commitments to obtain additional funds and no assurance can be given that any such financing will be available in the future — when needed, in sufficient amounts, on acceptable terms, or at all. If the Company cannot obtain the necessary funding, it may need to, among other things, delay, continue to scale back or eliminate research and development programs, modify its overall development strategy for one or more product candidates (or the Company as a whole) in a manner it would not if sufficient cash resources were available, or cease operations altogether. Operations of the Company are subject to certain additional risks and uncertainties as well, and any one or more of these factors could materially affect the Company’s financial condition, future operations and liquidity needs. Many of these risks and uncertainties are outside of the Company’s control, including the outcome of its pending merger with EIP and various internal and external factors that may affect the success or failure of the Company's research and development efforts, the length of time and cost of developing and commercializing the Company's current or future product candidates, whether and when any such product candidates become approved drugs, and how significant a drug's market share will be, if approved, among others. Without giving effect to the consummation of the proposed Merger with EIP, the Company currently expect that its existing cash and cash equivalents as of June 30, 2023 are sufficient to fund current operations for at least 12 months following the date of this Quarterly Report.

Note 3 - Basis of Presentation

Note 3 - Basis of Presentation and Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Significant Accounting Policies [Text Block]	3. Basis of Presentation and Summary of Significant Accounting Policies As of the date of this Quarterly Report, the Summary of Significant Accounting Policies included in the Company's Annual Report have not materially changed. Basis of Presentation The accompanying unaudited interim consolidated financial statements of the Company have been prepared in accordance with GAAP for interim financial information as found in the ASC and ASUs of the FASB, and with the instructions to Form 10-Q and Article 10 of Regulation S-X promulgated by the SEC. In the opinion of management, the accompanying unaudited interim consolidated financial statements of the Company include all normal and recurring adjustments (which consist primarily of accruals, estimates and assumptions that impact the unaudited interim consolidated financial statements) considered necessary to present fairly the Company’s financial position as of June 30, 2023, and its results of operations for the three and six months ended June 30, 2023 and 2022 and cash flows for the six months ended June 30, 2023 and 2022. Operating results for the six months ended June 30, 2023 are not necessarily indicative of the results that may be expected for the year ending December 31, 2023. The unaudited interim consolidated financial statements presented herein do not contain the required disclosures under GAAP for annual financial statements. The accompanying unaudited interim consolidated financial statements should be read in conjunction with the annual audited financial statements and related notes as of and for the year ended December 31, 2022 filed with the SEC as part of the Annual Report on Form 10-K. Use of Estimates The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. On an ongoing basis, the Company evaluates its estimates using historical experience and other factors, including the current economic environment. Significant items subject to such estimates are assumptions used for purposes of determining stock-based compensation and accounting for research and development activities. Management believes its estimates to be reasonable under the circumstances. Actual results could differ significantly from those estimates. Fair Value of Financial Instruments The carrying amounts of the Company’s financial instruments, including cash, cash equivalents, and accounts payable approximate fair value due to the short-term nature of those instruments. Concentration of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents, and marketable securities. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits. The Company has not experienced any losses in such accounts and believes it is not exposed to significant risk on its cash, cash equivalents, and marketable securities. Cash and Cash Equivalents The Company considers any highly-liquid investments, such as money market funds, with an original maturity of three months or less to be cash equivalents. Marketable securities The Company classifies its marketable securities as available-for-sale, which include commercial paper and U.S. government debt securities with original maturities of greater than three months from date of purchase. The Company considers its marketable securities as available for use in current operations, and therefore classifies these securities as current assets on the consolidated balance sheet. These securities are carried at fair value, with unrealized gains and losses reported in comprehensive loss and accumulated other comprehensive loss within stockholders’ equity. Gains or losses on marketable securities sold are based on the specific identification method. The Company routinely monitors the difference between cost and the estimated fair value of its investments. Each reporting period, securities with unrealized losses are reviewed to determine whether the decline in fair value requires the recognition of an allowance for credit losses. Factors considered in the review include (i) current market interest rates, (ii) general financial condition of the issuer, (iii) issuers industry and future business prospects, (iv) issuers past defaults in principal and interest payments, and (v) the payment structure of the investment and the issuers ability to make contractual payments on the investment. All of the Company's marketable securities were fully matured at June 30, 2023. Research and Development Major components of research and development costs include internal research and development (such as salaries and related employee benefits, equity-based compensation, supplies and allocated facility costs) and contracted services (research and development activities performed on the Company’s behalf). Costs incurred for research and development are expensed as incurred. Upfront payments made to third parties who perform research and development services on the Company’s behalf are expensed as services are rendered. Patent Costs Patent costs, including related legal costs, are expensed as incurred and are recorded within general and administrative expenses in the consolidated statements of operations and comprehensive loss. Stock-based Compensation The Company measures stock-based awards at grant-date fair value and records compensation expense on a straight-line basis over the vesting period of the award. The Company uses the Black-Scholes model to value its stock option awards. Estimating the fair value of stock option awards requires management to apply judgment and make estimates, including the volatility of the Company’s common stock, the expected term of the Company’s stock options, the expected dividend yield and the fair value of the Company’s common stock on the measurement date. As a result, if factors change and management uses different assumptions, stock-based compensation expense could be materially different for future awards. For stock option grants, the expected term was estimated using the “simplified method” for employee options as the Company has limited historical information to develop reasonable expectations about future exercise patterns and post vesting employment termination behavior for its stock option grants. The simplified method is based on the average of the vesting tranches and the contractual life of each grant. The Company uses the simplified method to estimate the expected term. For stock price volatility, the Company uses a combination of its own historical stock price and comparable public companies as a basis for its expected volatility to calculate the fair value of option grants. The Company assumes no dividend yield because dividends are not expected to be paid in the near future, which is consistent with the Company’s history of not paying dividends. The risk-free interest rate is based on U.S. Treasury notes with a term approximating the expected term of the option. The Company accounts for forfeitures in the periods in which they occur. Net Loss Per Common Share Basic net loss per share is computed by dividing net loss by the weighted average number of shares of common stock outstanding during each period. Diluted net loss per share includes the effect, if any, from the potential exercise or conversion of securities, such as common stock warrants, stock options and unvested restricted stock that would result in the issuance of incremental shares of common stock. In computing the basic and diluted net loss per share applicable to common stockholders, the weighted average number of shares remains the same for both calculations due to the fact that when a net loss exists, dilutive shares are not included in the calculation as the impact is anti-dilutive. The following potentially dilutive securities outstanding have been excluded from the computation of diluted weighted average shares outstanding, as they would be anti-dilutive: June 30, 2023 2022 Common stock warrants 88,252 111,891 Stock options 85,961 122,882 Unvested restricted stock awards 2,495 4,672 176,708 239,445 Recently Adopted Accounting Pronouncements In June 2016, the FASB issued ASU 2016-13, Financial Instruments Credit Losses, Measurement of Credit Losses on Financial Instruments The updated guidance in ASU 2016-13 also amended the previous other-than-temporary impairment (“OTTI”) model for available-for-sale fixed income securities by requiring the recognition of impairments relating to credit losses through an allowance account and limits the amount of credit loss to the difference between a security’s amortized cost basis and its fair value. In addition, the length of time a security has been in an unrealized loss position will no longer impact the determination of whether a credit loss exists. The Company adopted the guidance related to available-for-sale fixed income securities on January 1, 2023 using a prospective transition approach for available-for-sale fixed income securities that were purchased with credit deterioration or had recognized an OTTI write-down prior to the effective date. The effect of the prospective transition approach was to maintain the same amortized cost basis before and after the effective date.

Note 4 - Cash, Cash Equivalents

Note 4 - Cash, Cash Equivalents and Marketable Securities	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Cash, Cash Equivalents, and Marketable Securities [Text Block]	4. Cash, cash equivalents and marketable securities The following is a summary of the Company's cash and cash equivalents as of the date indicated: June 30, 2023 December 31, 2022 Cash in banking institutions $ 1,316,052 $ 1,586,920 Money market funds 13,683,496 8,526,786 Total $ 14,999,548 $ 10,113,706 The following is a summary of the Company's marketable securities as of as of the date indicated: Amortized cost Unrealized gains Unrealized losses Fair Value December 31, 2022 Commercial paper $ 9,445,220 263 $ (21,313 ) $ 9,424,170 U.S. treasury bonds 2,999,095 — (14,325 ) 2,984,770 Total $ 12,444,315 263 $ (35,638 ) $ 12,408,940 The Company had no marketable securities as of June 30, 2023.

Note 5 - Fair Value of Financia

Note 5 - Fair Value of Financial Instruments	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Fair Value Disclosures [Text Block]	5. Fair Value of Financial Instruments Fair value is the price that could be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. Fair value determination in accordance with applicable accounting guidance requires that a number of significant judgments be made. Additionally, fair value is used on a nonrecurring basis to evaluate assets for impairment or as required for disclosure purposes by applicable accounting guidance on disclosures about fair value of financial instruments. Depending on the nature of the assets and liabilities, various valuation techniques and assumptions are used when estimating fair value. The carrying amounts of certain of the Company’s financial instruments, including prepaid expense and accounts payable, are shown at cost, which approximates fair value due to the short-term nature of these instruments. The Company follows the provisions of FASB ASC Topic 820, Fair Value Measurement • Level 1: Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities. • Level 2: Quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liabilities. • Level 3: Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). The following table presents the Company’s assets that are measured at fair value on a recurring basis (amounts in thousands): Fair value measurement at reporting date Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) June 30, 2023 Cash equivalents: Money market funds $ 13,683,496 $ — $ — Total cash equivalents $ 13,683,496 $ — $ — December 31, 2022: Cash equivalents: Money market funds $ 8,526,786 $ — $ — Commercial paper — — — Total cash equivalents $ 8,526,786 $ — $ — Marketable securities: Commercial paper $ — $ 9,424,170 $ — US treasury — 2,984,770 — Total marketable securities $ — $ 12,408,940 $ — Total financial assets $ 8,526,786 $ 12,408,940 $ — The fair values of the Company’s Level 2 marketable securities are estimated primarily based on benchmark yields, reported trades, market-based quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, and reference data including market research publications, which represent a market approach. In general, a market approach is utilized if there is readily available and relevant market activity for an individual security. This valuation technique may change from period to period, based on the relevance and availability of market data.

Note 6 - Accrued Expenses and O

Note 6 - Accrued Expenses and Other Current Liabilities	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block]	6. Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following as of the dates indicated below: June 30, 2023 December 31, 2022 Accrued payroll and payroll related expenses $ 265,382 $ 131,777 Accrued professional fees 208,900 552,785 Accrued clinical studies expenses — 475,141 Other 58,268 129,851 Total $ 532,550 $ 1,289,554

Note 7 - Stockholders' Equity a

Note 7 - Stockholders' Equity and Common Stock Warrants	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Equity [Text Block]	7. Stockholders' Equity and Common Stock Warrants Common Stock Warrants As of June 30, 2023, the Company had the following warrants outstanding to acquire shares of its common stock: Outstanding Range of exercise price per share Expiration dates Common stock warrants issued related to the May 2019 common stock offering 27,648 $250.09 - $306.04 May and December 2024 Common stock warrants issued related to the November 2019 common stock offering 4,269 $17.51 May 2024 Common stock warrants issued related to the December 2019 common stock offering 6,264 $21.68 - $34.92 December 2024 and June 2025 Common stock warrants issued related to the May 2020 common stock offering 11,424 $65.65 March 2025 Common stock warrants issued related to the May 2020 investor warrant exercise 4,998 $29.7 November 2025 Common stock warrants issued related to the February 2021 common stock offering 33,649 $64.08 February 2026 88,252 During the six months ended June 30, 2023, 23,639 warrants expired.

Note 8- Stock-based Compensatio

Note 8- Stock-based Compensation	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Share-Based Payment Arrangement [Text Block]	8. Stock-Based Compensation 2015 Equity Plan The 2015 Equity Plan provides for increases to the number of shares reserved for issuance thereunder each January 1 equal to 4.0% of the total shares of the Company’s common stock outstanding as of the immediately preceding December 31, unless a lesser amount is stipulated by the Compensation Committee of the Company's board of directors. Accordingly, 81,582 shares were added to the reserve as of January 1, 2023, which shares may be issued in connection with the grant of stock-based awards, including stock options, restricted stock, restricted stock units, stock appreciation rights and other types of awards as deemed appropriate, in each case, in accordance with the terms of the 2015 Equity Plan. As of June 30, 2023, there were 160,254 shares available for future issuance under the 2015 Equity Plan. The Company recorded stock-based compensation expense in the following expense categories of its unaudited interim consolidated statements of operations and comprehensive loss for the periods indicated: Three Months Ended June 30, Six Months Ended June 30, 2023 2022 2023 2022 Research and development $ — $ 58,892 $ 12,011 $ 117,785 General and administrative 60,665 219,238 170,025 438,476 Total stock-based compensation expense $ 60,665 $ 278,130 $ 182,036 $ 556,261 The following table summarizes the activity related to all stock option grants for the six months ended June 30, 2023: Number of Options Weighted average exercise price per share Weighted average remaining contractual life (in years) Aggregate intrinsic value Balance at January 1, 2023 140,040 $ 126.75 Granted — — Cancelled (54,079 ) 22.04 Outstanding at June 30, 2023 85,961 $ 192.65 7.65 $ — Exercisable at June 30, 2023 68,344 $ 238.46 7.42 $ — Vested and expected to vest at June 30, 2023 85,961 $ 192.65 7.65 $ — There were no options granted during the six months ended June 30, 2023. The total fair value of options vested during the three months ended June 30, 2023 and 2022 was $0.1 million and $0.3 million, respectively. The total fair value of options vested during the six months ended June 30, 2023 and 2022 was $0.2 million and $0.5 million, respectively. No options were exercised during any of the periods presented. At June 30, 2023, there was $0.2 million of unrecognized compensation expense that will be recognized over a weighted-average period of 1.12 years. Restricted Stock Unit Awards The Company previously issued restricted stock units (each, an "RSU") to newly elected, non-executive members of the board of directors that vest in six, tri-monthly installments beginning 18 months after the respective grant date. The fair value of an RSU is equal to the fair market value price of the Company’s common stock on the date of grant. RSU expense is recorded on a straight-line basis over the service period. The following table summarizes activity related to RSU awards during the period indicated: Number of Units Weighted average grant date fair value Balance at January 1, 2022 3,652 $ 36.49 Vested (1) (1,157 ) 36.04 Outstanding at June 30, 2023 2,495 $ 37.57 (1) The RSUs vested during the six months ended June 30, 2023 were settled on a hybrid basis. The Company withheld 512 shares of common stock and, in lieu of delivering such shares, paid the RSU holder an amount in cash equal to the fair market value of such shares on the vesting date, representing the holder's approximate tax liability associated with the vesting. The Company recognized an insignificant amount in expense related to these awards and $16,000 in expense related to these awards during the three months ended June 30, 2023 and June 30, 2022, respectively. The Company recognized an insignificant amount and $32,000 in expense related to these awards during the six months ended June 30, 2023 and 2022, respectively. At June 30, 2023, there was $19,000 in unrecognized compensation cost that will be recognized over a weighted average period of 0.88 years.

Note 9 - Commitments and Contin

Note 9 - Commitments and Contingencies	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Commitments and Contingencies Disclosure [Text Block]	9. Commitments and Contingencies Office Space Lease Commitment The Company has a short-term agreement to utilize membership-based co-working space in Charlottesville, Virginia and was previously party to a second, similar agreement for co-working space in Philadelphia, Pennsylvania, which was terminated during the year ended December 31, 2022. Rent expense related to the Company's short-term agreements was approximately $1,000 and $2,000 for the three months ended June 30, 2023 and 2022, respectively. Rent expense related to the Company's short-term agreements was approximately $2,000 and $11,000 for the six months ended June 30, 2023 and 2022, respectively. Research and Development Arrangements Prior to the strategic review process and entry into the Merger Agreement with EIP, in the course of normal business operations, the Company would enter into agreements with universities and CROs to assist in the performance of research and development activities and contract manufacturers to assist with chemistry, manufacturing, and controls related expenses. Expenditures to CROs represented a significant cost in clinical development for the Company. The Company could also enter into additional collaborative research, contract research, manufacturing, and supplier agreements in the future, which may require upfront payments and long-term commitments of cash. Defined Contribution Retirement Plan The Company has established its 401(k) Plan, which covers all employees who qualify under the terms of the plan. Eligible employees may elect to contribute to the 401(k) Plan up to 90% of their compensation, limited by the IRS-imposed maximum. The Company provides a safe harbor match with a maximum amount of 4% of the participant’s compensation. The Company made matching contributions under the 401(k) Plan of approximately $10,000 and $26,000 for the three months ended June 30, 2023 and 2022, respectively. The Company made matching contributions under the 401(k) Plan of approximately $35,000 and $53,000 for the six months ended June 30, 2023 and 2022, respectively. Legal Proceedings On August 7, 2014, a complaint was filed in the Superior Court of Los Angeles County, California by Paul Feller, the former Chief Executive Officer of the Company’s legal predecessor under the caption Paul Feller v. RestorGenex Corporation, Pro Sports & Entertainment, Inc., ProElite, Inc. and Stratus Media Group, GmbH (Case No. BC553996). The complaint asserts various causes of action, including, among other things, promissory fraud, negligent misrepresentation, breach of contract, breach of employment agreement, breach of the covenant of good faith and fair dealing, violations of the California Labor Code and common counts. The plaintiff is seeking, among other things, compensatory damages in an undetermined amount, punitive damages, accrued interest and an award of attorneys’ fees and costs. On December 30, 2014, the Company filed a petition to compel arbitration and a motion to stay the action. On April 1, 2015, the plaintiff filed a petition in opposition to the Company’s petition to compel arbitration and a motion to stay the action. After a related hearing on April 14, 2015, the court granted the Company’s petition to compel arbitration and a motion to stay the action. On January 8, 2016, the plaintiff filed an arbitration demand with the American Arbitration Association. On November 19, 2018 at an Order to Show Cause Re Dismissal Hearing, the court found sufficient grounds not to dismiss the case and an arbitration hearing was scheduled, originally for November 2020 but later postponed due to the COVID-19 pandemic and related restrictions on gatherings in the State of California. In addition, following the November 2018 hearing, an automatic stay was placed on the arbitration in connection with the plaintiff filing for personal bankruptcy protection. On October 22, 2021, following a determination by the bankruptcy trustee not to pursue the claims and release them back to the plaintiff, the parties entered into a stipulation to abandon arbitration and return the matter to state court. A case management conference was held on February 23, 2022 at which an initial trial date of May 24, 2023 was set, and the parties have agreed to stipulate to mediation in advance of the trial. On October 20, 2022, the parties filed a joint stipulation to continue the trial and certain deadlines related to the mediation in order to allow plaintiff's counsel to continue to seek treatment for an ongoing medical issue. On November 1, 2022, based on the parties joint stipulation, the court entered an order continuing the trial date to October 25, 2023. The Company believes the claims in this matter are without merit and is defending itself vigorously. However, at this stage, the Company is unable to predict the outcome and possible loss or range of loss, if any, associated with its resolution or any potential effect the matter may have on the Company’s financial position. Depending on the outcome or resolution of this matter, it could have a material effect on the Company’s consolidated financial position, results of operations and cash flows. Following announcement of the Merger Agreement with EIP and the initial filing on May 11, 2023 of the Company’s Registration Statement on Form S-4 (File No. 333-271823) (the “Registration Statement”), two lawsuits were filed in the United States District Court for the Southern District of New York on May 15, 2023 and May 17, 2023, respectively, by purported stockholders of the Company in connection with the Merger. The lawsuits are captioned Dunlea v. Diffusion Pharmaceuticals, Inc., et al., No. 1:23-cv-04043 (S.D.N.Y.) and Pikazin v. Diffusion Pharmaceuticals, Inc., et al., No. 1:23-cv-04096 (S.D.N.Y.). Additional stockholder litigations were subsequently filed in the United States District Courts for the Southern District of New York and the District of Delaware and in the Delaware Court of Chancery (collectively with the first two cases, the “Actions”). The complaints in each of the Actions named as defendants the Company and the members of the Company’s board of directors as of such dates. Each of the federal court complaints alleges claims for violations of Section 14(a) of the Exchange Act and Rule 14a-9 promulgated thereunder against all defendants, and violations of Section 20(a) of the Exchange Act against such members of the Company’s board of directors. The Chancery Court complaint, filed after the stockholder had received copies of certain documents in response to a books and records demand under Section 220 of the Delaware General Corporation Law, alleges a claim for breach of fiduciary duty. The plaintiff in the Chancery Court action also sought expedited treatment and a preliminary injunction barring the scheduled stockholder vote, but those motions were subsequently withdrawn. The plaintiffs in each of the Actions contend that Registration Statement omitted or misrepresented material information regarding the proposed Merger, rendering the Registration Statement materially misleading. The Actions seek injunctive and declaratory relief, as well as damages. The Company has also received correspondence from law firms claiming to represent other purported stockholders making similar demands for additional disclosures relating to the Merger. The Company believes that the claims asserted in the Actions and the demand letters are without merit. Stockholders may serve additional demands and/or file additional lawsuits challenging the Merger, which may name the Company, EIP, members of the Company’s board of directors, members of the EIP board of directors and/or others as defendants. No assurance can be made as to the outcome of such additional demands, lawsuits, demand letters or the Actions, including the amount of costs associated with defending, settling, or any other liabilities that may be incurred in connection with the litigation or settlement of, such claims. If any additional demands are served and/or any additional lawsuits filed, absent new or different allegations that are material, the Company will not necessarily announce such additional demands and/or complaints, except as required by applicable law including the rules and regulations of the SEC.

Significant Accounting Policies

Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2023
Accounting Policies [Abstract]
Basis of Accounting, Policy [Policy Text Block]	Basis of Presentation The accompanying unaudited interim consolidated financial statements of the Company have been prepared in accordance with GAAP for interim financial information as found in the ASC and ASUs of the FASB, and with the instructions to Form 10-Q and Article 10 of Regulation S-X promulgated by the SEC. In the opinion of management, the accompanying unaudited interim consolidated financial statements of the Company include all normal and recurring adjustments (which consist primarily of accruals, estimates and assumptions that impact the unaudited interim consolidated financial statements) considered necessary to present fairly the Company’s financial position as of June 30, 2023, and its results of operations for the three and six months ended June 30, 2023 and 2022 and cash flows for the six months ended June 30, 2023 and 2022. Operating results for the six months ended June 30, 2023 are not necessarily indicative of the results that may be expected for the year ending December 31, 2023. The unaudited interim consolidated financial statements presented herein do not contain the required disclosures under GAAP for annual financial statements. The accompanying unaudited interim consolidated financial statements should be read in conjunction with the annual audited financial statements and related notes as of and for the year ended December 31, 2022 filed with the SEC as part of the Annual Report on Form 10-K.
Use of Estimates, Policy [Policy Text Block]	Use of Estimates The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. On an ongoing basis, the Company evaluates its estimates using historical experience and other factors, including the current economic environment. Significant items subject to such estimates are assumptions used for purposes of determining stock-based compensation and accounting for research and development activities. Management believes its estimates to be reasonable under the circumstances. Actual results could differ significantly from those estimates.
Fair Value of Financial Instruments, Policy [Policy Text Block]	Fair Value of Financial Instruments The carrying amounts of the Company’s financial instruments, including cash, cash equivalents, and accounts payable approximate fair value due to the short-term nature of those instruments.
Concentration Risk, Credit Risk, Policy [Policy Text Block]	Concentration of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents, and marketable securities. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits. The Company has not experienced any losses in such accounts and believes it is not exposed to significant risk on its cash, cash equivalents, and marketable securities.
Cash and Cash Equivalents, Policy [Policy Text Block]	Cash and Cash Equivalents The Company considers any highly-liquid investments, such as money market funds, with an original maturity of three months or less to be cash equivalents.
Marketable Securities, Policy [Policy Text Block]	Marketable securities The Company classifies its marketable securities as available-for-sale, which include commercial paper and U.S. government debt securities with original maturities of greater than three months from date of purchase. The Company considers its marketable securities as available for use in current operations, and therefore classifies these securities as current assets on the consolidated balance sheet. These securities are carried at fair value, with unrealized gains and losses reported in comprehensive loss and accumulated other comprehensive loss within stockholders’ equity. Gains or losses on marketable securities sold are based on the specific identification method. The Company routinely monitors the difference between cost and the estimated fair value of its investments. Each reporting period, securities with unrealized losses are reviewed to determine whether the decline in fair value requires the recognition of an allowance for credit losses. Factors considered in the review include (i) current market interest rates, (ii) general financial condition of the issuer, (iii) issuers industry and future business prospects, (iv) issuers past defaults in principal and interest payments, and (v) the payment structure of the investment and the issuers ability to make contractual payments on the investment. All of the Company's marketable securities were fully matured at June 30, 2023.
Research and Development Expense, Policy [Policy Text Block]	Research and Development Major components of research and development costs include internal research and development (such as salaries and related employee benefits, equity-based compensation, supplies and allocated facility costs) and contracted services (research and development activities performed on the Company’s behalf). Costs incurred for research and development are expensed as incurred. Upfront payments made to third parties who perform research and development services on the Company’s behalf are expensed as services are rendered.
Legal Costs, Policy [Policy Text Block]	Patent Costs Patent costs, including related legal costs, are expensed as incurred and are recorded within general and administrative expenses in the consolidated statements of operations and comprehensive loss.
Share-Based Payment Arrangement [Policy Text Block]	Stock-based Compensation The Company measures stock-based awards at grant-date fair value and records compensation expense on a straight-line basis over the vesting period of the award. The Company uses the Black-Scholes model to value its stock option awards. Estimating the fair value of stock option awards requires management to apply judgment and make estimates, including the volatility of the Company’s common stock, the expected term of the Company’s stock options, the expected dividend yield and the fair value of the Company’s common stock on the measurement date. As a result, if factors change and management uses different assumptions, stock-based compensation expense could be materially different for future awards. For stock option grants, the expected term was estimated using the “simplified method” for employee options as the Company has limited historical information to develop reasonable expectations about future exercise patterns and post vesting employment termination behavior for its stock option grants. The simplified method is based on the average of the vesting tranches and the contractual life of each grant. The Company uses the simplified method to estimate the expected term. For stock price volatility, the Company uses a combination of its own historical stock price and comparable public companies as a basis for its expected volatility to calculate the fair value of option grants. The Company assumes no dividend yield because dividends are not expected to be paid in the near future, which is consistent with the Company’s history of not paying dividends. The risk-free interest rate is based on U.S. Treasury notes with a term approximating the expected term of the option. The Company accounts for forfeitures in the periods in which they occur.
Earnings Per Share, Policy [Policy Text Block]	Net Loss Per Common Share Basic net loss per share is computed by dividing net loss by the weighted average number of shares of common stock outstanding during each period. Diluted net loss per share includes the effect, if any, from the potential exercise or conversion of securities, such as common stock warrants, stock options and unvested restricted stock that would result in the issuance of incremental shares of common stock. In computing the basic and diluted net loss per share applicable to common stockholders, the weighted average number of shares remains the same for both calculations due to the fact that when a net loss exists, dilutive shares are not included in the calculation as the impact is anti-dilutive. The following potentially dilutive securities outstanding have been excluded from the computation of diluted weighted average shares outstanding, as they would be anti-dilutive: June 30, 2023 2022 Common stock warrants 88,252 111,891 Stock options 85,961 122,882 Unvested restricted stock awards 2,495 4,672 176,708 239,445
New Accounting Pronouncements, Policy [Policy Text Block]	Recently Adopted Accounting Pronouncements In June 2016, the FASB issued ASU 2016-13, Financial Instruments Credit Losses, Measurement of Credit Losses on Financial Instruments The updated guidance in ASU 2016-13 also amended the previous other-than-temporary impairment (“OTTI”) model for available-for-sale fixed income securities by requiring the recognition of impairments relating to credit losses through an allowance account and limits the amount of credit loss to the difference between a security’s amortized cost basis and its fair value. In addition, the length of time a security has been in an unrealized loss position will no longer impact the determination of whether a credit loss exists. The Company adopted the guidance related to available-for-sale fixed income securities on January 1, 2023 using a prospective transition approach for available-for-sale fixed income securities that were purchased with credit deterioration or had recognized an OTTI write-down prior to the effective date. The effect of the prospective transition approach was to maintain the same amortized cost basis before and after the effective date.

Note 3 - Basis of Presentatio_2

Note 3 - Basis of Presentation and Summary of Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]	June 30, 2023 2022 Common stock warrants 88,252 111,891 Stock options 85,961 122,882 Unvested restricted stock awards 2,495 4,672 176,708 239,445

Note 4 - Cash, Cash Equivalen_2

Note 4 - Cash, Cash Equivalents and Marketable Securities (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Schedule of Cash and Cash Equivalents [Table Text Block]	June 30, 2023 December 31, 2022 Cash in banking institutions $ 1,316,052 $ 1,586,920 Money market funds 13,683,496 8,526,786 Total $ 14,999,548 $ 10,113,706
Debt Securities, Available-for-Sale [Table Text Block]	Amortized cost Unrealized gains Unrealized losses Fair Value December 31, 2022 Commercial paper $ 9,445,220 263 $ (21,313 ) $ 9,424,170 U.S. treasury bonds 2,999,095 — (14,325 ) 2,984,770 Total $ 12,444,315 263 $ (35,638 ) $ 12,408,940

Note 5 - Fair Value of Financ_2

Note 5 - Fair Value of Financial Instruments (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Fair Value, Assets Measured on Recurring Basis [Table Text Block]	Fair value measurement at reporting date Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) June 30, 2023 Cash equivalents: Money market funds $ 13,683,496 $ — $ — Total cash equivalents $ 13,683,496 $ — $ — December 31, 2022: Cash equivalents: Money market funds $ 8,526,786 $ — $ — Commercial paper — — — Total cash equivalents $ 8,526,786 $ — $ — Marketable securities: Commercial paper $ — $ 9,424,170 $ — US treasury — 2,984,770 — Total marketable securities $ — $ 12,408,940 $ — Total financial assets $ 8,526,786 $ 12,408,940 $ —

Note 6 - Accrued Expenses and_2

Note 6 - Accrued Expenses and Other Current Liabilities (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Other Current Liabilities [Table Text Block]	June 30, 2023 December 31, 2022 Accrued payroll and payroll related expenses $ 265,382 $ 131,777 Accrued professional fees 208,900 552,785 Accrued clinical studies expenses — 475,141 Other 58,268 129,851 Total $ 532,550 $ 1,289,554

Note 7 - Stockholders' Equity_2

Note 7 - Stockholders' Equity and Common Stock Warrants (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]	Outstanding Range of exercise price per share Expiration dates Common stock warrants issued related to the May 2019 common stock offering 27,648 $250.09 - $306.04 May and December 2024 Common stock warrants issued related to the November 2019 common stock offering 4,269 $17.51 May 2024 Common stock warrants issued related to the December 2019 common stock offering 6,264 $21.68 - $34.92 December 2024 and June 2025 Common stock warrants issued related to the May 2020 common stock offering 11,424 $65.65 March 2025 Common stock warrants issued related to the May 2020 investor warrant exercise 4,998 $29.7 November 2025 Common stock warrants issued related to the February 2021 common stock offering 33,649 $64.08 February 2026 88,252

Note 8- Stock-based Compensat_2

Note 8- Stock-based Compensation (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]	Three Months Ended June 30, Six Months Ended June 30, 2023 2022 2023 2022 Research and development $ — $ 58,892 $ 12,011 $ 117,785 General and administrative 60,665 219,238 170,025 438,476 Total stock-based compensation expense $ 60,665 $ 278,130 $ 182,036 $ 556,261
Share-Based Payment Arrangement, Option, Activity [Table Text Block]	Number of Options Weighted average exercise price per share Weighted average remaining contractual life (in years) Aggregate intrinsic value Balance at January 1, 2023 140,040 $ 126.75 Granted — — Cancelled (54,079 ) 22.04 Outstanding at June 30, 2023 85,961 $ 192.65 7.65 $ — Exercisable at June 30, 2023 68,344 $ 238.46 7.42 $ — Vested and expected to vest at June 30, 2023 85,961 $ 192.65 7.65 $ —
Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block]	Number of Units Weighted average grant date fair value Balance at January 1, 2022 3,652 $ 36.49 Vested (1) (1,157 ) 36.04 Outstanding at June 30, 2023 2,495 $ 37.57

Note 3 - Basis of Presentatio_3

Note 3 - Basis of Presentation and Summary of Significant Accounting Policies - Outstanding Dilutive Securities (Details) - shares	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Antidilutive securities (in shares)	176,708	239,445
Warrant [Member]
Antidilutive securities (in shares)	88,252	111,891
Share-Based Payment Arrangement, Option [Member]
Antidilutive securities (in shares)	85,961	122,882
Unvested Restricted Stock Units [Member]
Antidilutive securities (in shares)	2,495	4,672

Note 4 - Cash, Cash Equivalen_3

Note 4 - Cash, Cash Equivalents and Marketable Securities - Cash and Cah Equivalents (Details) - USD ($)	Jun. 30, 2023	Dec. 31, 2022
Cash and cash equivalents	$ 14,999,548	$ 10,113,706
Bank Time Deposits [Member]
Cash and cash equivalents	1,316,052	1,586,920
Money Market Funds [Member]
Cash and cash equivalents	$ 13,683,496	$ 8,526,786

Note 4 - Cash, Cash Equivalen_4

Note 4 - Cash, Cash Equivalents and Marketable Securities - Marketable Securities (Details)	Jun. 30, 2023 USD ($)
Amortized cost	$ 12,444,315
Unrealized gains	263
Unrealized losses	(35,638)
Fair value	12,408,940
Fair value	12,408,940
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Amortized cost	9,445,220
Unrealized gains	263
Unrealized losses	(21,313)
Fair value	9,424,170
Fair value	9,424,170
US Treasury Securities [Member]
Amortized cost	2,999,095
Unrealized gains	0
Unrealized losses	(14,325)
Fair value	2,984,770
Fair value	$ 2,984,770

Note 5 - Fair Value of Financ_3

Note 5 - Fair Value of Financial Instruments - Assets Measured at Fair Value on Recurring Basis (Details) - USD ($)	Jun. 30, 2023	Dec. 31, 2022
Fair value	$ 12,408,940
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Fair value	9,424,170
US Treasury Securities [Member]
Fair value	2,984,770
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Money market funds	13,683,496	$ 8,526,786
Fair value		0
Total financial assets		8,526,786
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member] | Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Fair value		0
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member] | US Treasury Securities [Member]
Fair value		0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Money market funds	0	0
Fair value		12,408,940
Total financial assets		12,408,940
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member] | Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Fair value		9,424,170
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member] | US Treasury Securities [Member]
Fair value		2,984,770
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Money market funds	13,683,496	8,526,786
Money Market Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Money market funds	$ 0	0
Commercial Paper [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Money market funds		0
Commercial Paper [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Money market funds		$ 0

Note 6 - Accrued Expenses and_3

Note 6 - Accrued Expenses and Other Current Liabilities - Summary of Accrued Expenses (Details) - USD ($)	Jun. 30, 2023	Dec. 31, 2022
Accrued payroll and payroll related expenses	$ 265,382	$ 131,777
Accrued professional fees	208,900	552,785
Accrued clinical studies expenses	0	475,141
Other	58,268	129,851
Total	$ 532,550	$ 1,289,554

Note 7 - Stockholders' Equity_3

Note 7 - Stockholders' Equity and Common Stock Warrants (Details Textual)	6 Months Ended
	Jun. 30, 2023 shares
Class of Warrant or Rights, Expired	23,639

Note 7 - Stockholders' Equity_4

Note 7 - Stockholders' Equity and Common Stock Warrants - Warrants Outstanding to Acquire Shares of Its Common Stock (Details)	Jun. 30, 2023 $ / shares shares
Common stock warrants issued (in shares) | shares	88,252
Warrants Issued in Connection with May 2019 Public Offering [Member]
Common stock warrants issued (in shares) | shares	27,648
Warrants Issued in Connection with May 2019 Public Offering [Member] | Minimum [Member]
Common stock warrants issued, exercise price (in dollars per share)	$ 250.09
Warrants Issued in Connection with May 2019 Public Offering [Member] | Maximum [Member]
Common stock warrants issued, exercise price (in dollars per share)	$ 306.04
Warrants Issued in Connection with the November 2019 Offering [Member]
Common stock warrants issued (in shares) | shares	4,269
Common stock warrants issued, exercise price (in dollars per share)	$ 17.51
Warrants Issued in Connection with the December 2019 Offering [Member]
Common stock warrants issued (in shares) | shares	6,264
Warrants Issued in Connection with the December 2019 Offering [Member] | Minimum [Member]
Common stock warrants issued, exercise price (in dollars per share)	$ 21.68
Warrants Issued in Connection with the December 2019 Offering [Member] | Maximum [Member]
Common stock warrants issued, exercise price (in dollars per share)	$ 34.92
The May 2020 Offering Warrants [Member]
Common stock warrants issued (in shares) | shares	11,424
Common stock warrants issued, exercise price (in dollars per share)	$ 65.65
The May 2020 Investor Warrant Exercise [Member]
Common stock warrants issued (in shares) | shares	4,998
Common stock warrants issued, exercise price (in dollars per share)	$ 29.7
Underwriter Warrants in Connection with the February 2021 Common Stock Offering [Member]
Common stock warrants issued (in shares) | shares	33,649
Common stock warrants issued, exercise price (in dollars per share)	$ 64.08

Note 8- Stock-based Compensat_3

Note 8- Stock-based Compensation (Details Textual) - USD ($)		3 Months Ended		6 Months Ended
	Jan. 01, 2023	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested in Period, Fair Value		$ 100,000	$ 300,000	$ 200,000	$ 500,000
Share-Based Payment Arrangement, Shares Withheld for Tax Withholding Obligation				512
Share-Based Payment Arrangement, Expense		60,665	278,130	$ 182,036	556,261
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		200,000		$ 200,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				1 year 1 month 13 days
Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period				18 months
Restricted Stock Units (RSUs) [Member] | Director [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		19,000,000,000		$ 19,000,000,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				10 months 17 days
Share-Based Payment Arrangement, Expense		$ 16,000	$ 16,000	$ 32,000	$ 32,000
Equity Incentive Plan 2015 [Member]
Percentage of Total Shares Eligible for Plan Reserve, On an Annual Basis				4%
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized	81,582
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant		160,254		160,254

Note 8 - Stock-based Compensati

Note 8 - Stock-based Compensation - Stock-based Compensation Expense (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Share based compensation expense	$ 60,665	$ 278,130	$ 182,036	$ 556,261
Research and Development Expense [Member]
Share based compensation expense	0	58,892	12,011	117,785
General and Administrative Expense [Member]
Share based compensation expense	$ 60,665	$ 219,238	$ 170,025	$ 438,476

Note 8 - Stock-based Compensa_2

Note 8 - Stock-based Compensation - Stock Option Activity (Details) $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2023 USD ($) $ / shares shares
Balance, number of shares (in shares) | shares	140,040
Balance, weighted average exercise price (in dollars per share) | $ / shares	$ 126.75
Granted, number of shares (in shares) | shares	0
Granted, weighted average exercise price (in dollars per share) | $ / shares	$ 0
Cancelled, number of shares (in shares) | shares	(54,079)
Cancelled, weighted average exercise price (in dollars per share) | $ / shares	$ 22.04
Outstanding , number of shares (in shares) | shares	85,961
Outstanding, weighted average exercise price (in dollars per share) | $ / shares	$ 192.65
Outstanding, remaining term (Year)	7 years 7 months 24 days
Outstanding, intrinsic value | $	$ 0
Exercisable, number of shares (in shares) | shares	68,344
Exercisable, weighted average exercise price (in dollars per share) | $ / shares	$ 238.46
Exercisable, remaining term (Year)	7 years 5 months 1 day
Exercisable, intrinsic value | $	$ 0
Vested and expected to vest, number of shares (in shares) | shares	85,961
Vested and expected to vest, weighted average exercise price (in dollars per share) | $ / shares	$ 192.65
Vested and expected to vest, remaining term (Year)	7 years 7 months 24 days
Vested and expected to vest , intrinsic value | $	$ 0

Note 8 - Stock-based Compensa_3

Note 8 - Stock-based Compensation - RSU Stock-based Payment Awards (Details) - Restricted Stock Units (RSUs) [Member]	6 Months Ended
	Jun. 30, 2023 $ / shares shares
Balance, units (in shares) | shares	3,652
Balance, weighted average grant date fair value (in dollars per share) | $ / shares	$ 36.49
Vested, units (in shares) | shares	(1,157)	[1]
Vested, weighted average grant date fair value (in dollars per share) | $ / shares	$ 36.04	[1]
Outstanding, units (in shares) | shares	2,495
Outstanding, weighted average grant date fair value (in dollars per share) | $ / shares	$ 37.57
[1]The RSUs vested during the six months ended June 30, 2023 were settled on a hybrid basis. The Company withheld 512 shares of common stock and, in lieu of delivering such shares, paid the RSU holder an amount in cash equal to the fair market value of such shares on the vesting date, representing the holder's approximate tax liability associated with the vesting

Note 9 - Commitments and Cont_2

Note 9 - Commitments and Contingencies (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Operating Lease, Expense	$ 1,000	$ 2,000	$ 2,000	$ 11,000
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent			90%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay			4%
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 10,000	$ 26,000	$ 35,000	$ 53,000