BioCardia (BCDA) 10-Q 9 Aug 23 2023 Q2 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2023	Jul. 31, 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	0-21419
Entity Registrant Name	BioCardia, Inc
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	23-2753988
Entity Address, Address Line One	320 Soquel Way
Entity Address, City or Town	Sunnyvale
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94085
City Area Code	650
Local Phone Number	226-0120
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)		21,619,432
Entity Central Index Key	0000925741
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
Amendment Flag	false
Common Stock [Member]
Document Information [Line Items]
Title of 12(b) Security	Common Stock, par value $0.001
Trading Symbol	BCDA
Security Exchange Name	NASDAQ
Warrant [Member]
Document Information [Line Items]
Title of 12(b) Security	Warrant to Purchase Common Stock
Trading Symbol	BCDAW
Security Exchange Name	NASDAQ

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($)	Jun. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 4,305,000	$ 7,363,000
Accounts receivable, net of allowance for doubtful accounts of $11 as of both June 30, 2023 and December 31, 2022	115,000	201,000
Prepaid expenses and other current assets	230,000	300,000
Total current assets	4,650,000	7,864,000
Property and equipment, net	139,000	170,000
Operating lease right-of-use asset, net	1,429,000	1,588,000
Other assets	171,000	171,000
Total assets	6,389,000	9,793,000
Current liabilities:
Accounts payable	686,000	683,000
Accrued expenses and other current liabilities	2,257,000	2,246,000
Deferred revenue	333,000	341,000
Operating lease liability - current	340,000	315,000
Total current liabilities	3,616,000	3,585,000
Operating lease liability - noncurrent	1,138,000	1,316,000
Total liabilities	4,754,000	4,901,000
Stockholders’ equity:
Preferred stock, $0.001 par value, 25,000,000 shares authorized and no shares issued and outstanding as of June 30, 2023 and December 31, 2022	0	0
Common stock, $0.001 par value, 100,000,000 shares authorized, 21,586,150 and 20,076,773 shares issued and outstanding as of June 30, 2023 and December 31, 2022, respectively	22,000	20,000
Additional paid-in capital	149,142,000	145,476,000
Accumulated deficit	(147,529,000)	(140,604,000)
Total stockholders’ equity	1,635,000	4,892,000
Total liabilities and stockholders’ equity	$ 6,389,000	$ 9,793,000

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Accounts Receivable, Allowance for Credit Loss, Current	$ 11		$ 11
Preferred Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001		$ 0.001
Preferred Stock, Shares Authorized (in shares)	25,000,000		25,000,000
Preferred Stock, Shares Issued (in shares)	0		0
Preferred Stock, Shares Outstanding (in shares)	0		0
Common Stock, Par or Stated Value Per Share (in dollars per share)		$ 0.001	$ 0.001
Common Stock, Shares Authorized (in shares)	100,000,000		100,000,000
Common Stock, Shares, Outstanding (in shares)	21,586,150		20,076,773
Common Stock, Shares, Issued (in shares)	21,586,150		20,076,773

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Revenue:
Net product revenue	$ 43	$ 974	$ 107	$ 1,034
Costs and expenses:
Research and development	2,314	2,304	4,698	4,490
Selling, general and administrative	1,181	1,166	2,371	2,367
Total costs and expenses	3,495	3,470	7,069	6,857
Operating loss	(3,452)	(2,496)	(6,962)	(5,823)
Other income (expense):
Total other income, net	28	(1)	37	1
Net loss	$ (3,424)	$ (2,497)	$ (6,925)	$ (5,822)
Net loss per share, basic and diluted (in dollars per share)	$ (0.17)	$ (0.14)	$ (0.34)	$ (0.34)
Weighted-average shares used in computing net loss per share, basic and diluted (in shares)	20,384,522	17,651,892	20,281,417	17,360,598
Product [Member]
Revenue:
Net product revenue	$ 0	$ 0	$ 0	$ 1
Collaboration Agreement [Member]
Revenue:
Net product revenue	$ 43	$ 974	$ 107	$ 1,033

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($)	Common Stock [Member] Management [Member] Restricted Stock Units (RSUs) [Member]	Common Stock [Member] ATM [Member]	Common Stock [Member]	Additional Paid-in Capital [Member] Management [Member] Restricted Stock Units (RSUs) [Member]	Additional Paid-in Capital [Member] ATM [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member] Management [Member] Restricted Stock Units (RSUs) [Member]	Retained Earnings [Member] ATM [Member]	Retained Earnings [Member]	Management [Member] Restricted Stock Units (RSUs) [Member]	ATM [Member]	Total
Balance (in shares) at Dec. 31, 2021			16,871,265
Balance at Dec. 31, 2021			$ 17,000			$ 139,055,000			$ (128,697,000)			$ 10,375,000
Share-based compensation						319,000						319,000
Net loss									(3,325,000)			(3,325,000)
Share-based compensation						319,000						319,000
Balance (in shares) at Mar. 31, 2022			16,871,265
Balance at Mar. 31, 2022			$ 17,000			139,374,000			(132,022,000)			7,369,000
Balance (in shares) at Dec. 31, 2021			16,871,265
Balance at Dec. 31, 2021			$ 17,000			139,055,000			(128,697,000)			10,375,000
Net loss												(5,822,000)
Balance (in shares) at Jun. 30, 2022			17,758,194,000
Balance at Jun. 30, 2022			$ 18,000			141,235,000			(134,519,000)			6,734
Balance (in shares) at Mar. 31, 2022			16,871,265
Balance at Mar. 31, 2022			$ 17,000			139,374,000			(132,022,000)			7,369,000
Share-based compensation			0			304,000			0			304,000
Net loss			$ 0			0			(2,497,000)			(2,497,000)
Stock Issued During Period, Shares, Restricted Stock Award, Gross (in shares)			311,929
Restricted stock units issued to settle management bonus obligations	$ 0			$ 271,000			$ 0			$ 271,000
Sale of common stock, net of issuance costs (in shares)		575,000
Sale of common stock, net of issuance costs		$ 1,000			$ 1,286,000			$ 0			$ 1,287,000
Share-based compensation			$ 0			304,000			0			304,000
Restricted stock units vested and issued (in shares)			311,929
Balance (in shares) at Jun. 30, 2022			17,758,194,000
Balance at Jun. 30, 2022			$ 18,000			141,235,000			(134,519,000)			6,734
Balance (in shares) at Dec. 31, 2022			20,076,773
Balance at Dec. 31, 2022			$ 20,000			145,476,000			(140,604,000)			4,892,000
Share-based compensation			0			278,000			0			278,000
Net loss			$ 0			0			(3,501,000)			(3,501,000)
Stock Issued During Period, Shares, Restricted Stock Award, Gross (in shares)			18,792
Sale of common stock, net of issuance costs (in shares)		106,241
Sale of common stock, net of issuance costs		$ 0			231,000			0			231,000
Share-based compensation			$ 0			278,000			0			278,000
Exercise of common stock options (in shares)			199
Exercise of common stock options						0						0
Restricted stock units vested and issued (in shares)			18,792
Balance (in shares) at Mar. 31, 2023			20,202,005
Balance at Mar. 31, 2023			$ 20,000			145,985,000			(144,105,000)			1,900,000
Balance (in shares) at Dec. 31, 2022			20,076,773
Balance at Dec. 31, 2022			$ 20,000			145,476,000			(140,604,000)			4,892,000
Net loss												$ (6,925,000)
Exercise of common stock options (in shares)												199
Balance (in shares) at Jun. 30, 2023			21,586,150
Balance at Jun. 30, 2023			$ 22,000			149,142,000			(147,529,000)			$ 1,635,000
Balance (in shares) at Mar. 31, 2023			20,202,005
Balance at Mar. 31, 2023			$ 20,000			145,985,000			(144,105,000)			1,900,000
Share-based compensation						317,000						317,000
Net loss									(3,424,000)			(3,424,000)
Stock Issued During Period, Shares, Restricted Stock Award, Gross (in shares)			222,405,000
Restricted stock units issued to settle management bonus obligations	$ 0			$ 342,000			$ 0			$ 342,000
Sale of common stock, net of issuance costs (in shares)		28,599	1,133,141
Sale of common stock, net of issuance costs		$ 0	$ 1,000		$ 29,000	2,469,000		$ 0	0		$ 29,000	2,470,000
Share-based compensation						317,000						317,000
Restricted stock units vested and issued (in shares)			222,405,000
Restricted stock units vested and issued			$ 1,000			0			0			1,000
Balance (in shares) at Jun. 30, 2023			21,586,150
Balance at Jun. 30, 2023			$ 22,000			$ 149,142,000			$ (147,529,000)			$ 1,635,000

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) (Parentheticals) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022
ATM [Member]
Issuance costs	$ 29	$ 13
Issuance costs	$ 177		$ 232

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Operating activities:
Net loss	$ (6,925)	$ (5,822)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	43	32
Reduction in the carrying amount of right-of-use assets	159	144
Share-based compensation	595	623
Changes in operating assets and liabilities:
Accounts receivable	86	(64)
Prepaid expenses and other current assets	70	136
Accounts payable	69	425
Accrued expenses and other current liabilities	353	(87)
Deferred revenue	(8)	(847)
Operating lease liability	(153)	(98)
Net cash used in operating activities	(5,711)	(5,558)
Investing activities:
Purchase of property and equipment	(12)	(54)
Net cash used in investing activities	(12)	(54)
Financing activities:
Proceeds from sales of common stock	2,950	1,519
Issuance costs of sale of common stock	(285)	(165)
Net cash provided by financing activities	2,665	1,354
Net change in cash and cash equivalents	(3,058)	(4,258)
Cash and cash equivalents at beginning of period	7,363	12,872
Cash and cash equivalents at end of period	4,305	8,614
Supplemental disclosure of noncash investing and financing activities:
Unpaid issuance costs of common stock	106	67
Issuance of restricted stock units in lieu of cash bonus obligations	$ 564	$ 401

Note 1 - Summary of Business an

Note 1 - Summary of Business and Basis of Presentation	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Business Description and Basis of Presentation [Text Block]	(1) Summary of Business and Basis of Presentation (a) Description of Business BioCardia, Inc. (we, us, our, BioCardia or the Company), is a clinical-stage company focused on developing cellular and cell-derived therapeutics for the treatment of cardiovascular and pulmonary diseases with significant unmet medical needs. We are advancing two cell therapy platforms derived from bone marrow in clinical trials today. Our CardiAMP® autologous mononuclear cell therapy platform is being advanced for two clinical indications: ischemic heart failure with reduced ejection fraction (HFrEF) and refractory angina resulting from chronic myocardial ischemia (CMI). Our neurokinin-1 receptor positive (NK1R+) allogeneic mesenchymal stem cell (MSC) therapy platform is being advanced as an “off the shelf” cell therapy for two clinical indications: the treatment of ischemic HFrEF and for acute respiratory distress syndrome (ARDS). Our autologous CardiAMP and our allogeneic NK1R+ cell therapies intended for cardiac indications of HFrEF and CMI are enabled by our Helix™ minimally invasive intramyocardial therapeutic delivery platform. We partner this therapeutic delivery platform selectively with others seeking to develop biotherapeutic interventions for local delivery to the heart. To date, we have devoted substantially all our resources to research and development efforts relating to our therapeutic candidates and biotherapeutic delivery systems including conducting clinical trials, developing manufacturing and sales capabilities, in-licensing related intellectual property, providing general and administrative support for these operations and protecting our intellectual property. We manage our operations as a single segment for the purposes of assessing performance and making operating decisions.

Note 2 - Significant Accounting

Note 2 - Significant Accounting Policies	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Significant Accounting Policies [Text Block]	(2) Significant Accounting Policies (a) Basis of Preparation The accompanying condensed consolidated balance sheets, statements of operations, stockholders’ equity, and cash flows as of June 30, 2023, and for the three and six months ended June 30, 2023 and 2022 are unaudited. The condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (U.S. GAAP) and applicable rules and regulations of the Securities and Exchange Commission (SEC) for interim financial information and on a basis consistent with the annual financial statements and, in the opinion of management, reflect all adjustments which include only normal recurring adjustments, necessary to present fairly its financial position as of June 30, 2023, 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. The results for the three and six months ended June 30, 2023 are not necessarily indicative of the results to be expected for the year ended December 31, 2023 or for any other interim period or for any other future year. These condensed consolidated financial statements should be read in conjunction with the audited financial statements and related notes included in our Annual Report on Form 10-K for the year ended December 31, 2022, filed with the SEC on March 29, 2023. (b) Liquidity Going Concern We have incurred net losses and negative cash flows from operations since our inception and had an accumulated deficit of approximately $147.5 million as of June 30, 2023. Management expects operating losses and negative cash flows to continue through at least the next several years. We expect to incur increasing costs as we advance our trials and development activities. Therefore, absent additional funding, management believes cash and cash equivalents of $4.3 million as of June 30, 2023 are not sufficient to fund the Company’s planned expenditures and meet its obligations beyond the fourth quarter of 2023. These factors raise substantial doubt about our ability to continue as a going concern beyond one year from the date these financial statements are issued. The financial statements do not include any adjustments that might result from the outcome of this uncertainty. Our ability to continue as a going concern and to continue further development of our therapeutic candidates beyond the fourth quarter of 2023 will require us to raise additional capital. We plan to raise additional capital, potentially including debt and equity arrangements, to finance our future operations. While management believes this plan to raise additional funds will alleviate the conditions that raise substantial doubt, these plans are not entirely within its control and cannot be assessed as being probable of occurring. If adequate funds are not available, we may be required to reduce operating expenses, delay or reduce the scope of our product development programs, obtain funds through arrangements with others that may require us to relinquish rights to certain of our technologies or products that we would otherwise seek to develop or commercialize, or cease operations. (c) Use of Estimates The preparation of the financial statements in accordance with U.S. GAAP requires management to make certain estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ materially from those estimates. Significant items subject to such estimates and assumptions include share-based compensation, the useful lives of property and equipment, right-of-use assets and related liabilities, incremental borrowing rate, allowances for doubtful accounts and sales returns, clinical accruals and assumptions used for revenue recognition. (d) Principles of Consolidation The condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary, BioCardia Lifesciences, Inc. All intercompany accounts and transactions have been eliminated during the consolidation process. (e) Concentration of Credit Risk Financial instruments that potentially subject us to a concentration of credit risk consist of cash and cash equivalents. Our cash at times exceeds federally insured limits of $250,000 per customer. On June 30, 2023, approximately 99% of our cash was held by one financial institution and total amounts on deposit were approximately $4.0 million in excess of FDIC insurance limits. We have not recognized any losses from credit risks on such accounts since inception. Silicon Valley Bank (SVB) was closed on March 10, 2023 by the California Department of Financial Protection and Innovation, which appointed the Federal Deposit Insurance Corporation (FDIC) as receiver. On March 12, 2023, a joint statement was issued by the Secretary of the Treasury and the Federal Reserve and the FDIC Chairman stating that all depositors would be fully protected and would have access to both insured and uninsured deposits starting March 12, 2203. The FDIC then established a bridge bank successor, Silicon Valley Bridge Bank, N.A., which quickly assumed ongoing business. On March 27, 2023, First Citizens Bank & Trust Company, a subsidiary of First Citizens BancShares, assumed all customer deposits and acquired all loans of Silicon Valley Bridge Bank from the FDIC and began operating all SVB branches. As of March 31, 2023, the Company transferred substantially all of its cash and cash equivalents from SVB to another financial institution and does not believe it will be impacted by the transition of SVB to First Citizens Bank & Trust Company. (f) Changes to Significant Accounting Policies Our significant accounting policies are described in Note 2 of the notes to the consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2022 filed March 29, 2023. There have been no changes to those policies. (g) Recent Accounting Pronouncements Recent accounting pronouncements issued by the Financial Accounting Standards Board (FASB), including its Emerging Issues Task Force, did not or are not believed by management to have a material impact on our financial statement presentation or disclosures.

Note 3 - Fair Value Measurement

Note 3 - Fair Value Measurement	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Fair Value Disclosures [Text Block]	(3) Fair Value Measurement The fair value of financial instruments reflects the amounts that we estimate to receive in connection with the sale of an asset or paid in connection with the transfer of a liability in an orderly transaction between market participants at the measurement date (exit price). We follow a fair value hierarchy that prioritizes the use of inputs used in valuation techniques into the following three levels: Level 1 – quoted prices in active markets for identical assets and liabilities. Level 2 – observable inputs other than quoted prices in active markets for identical assets and liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 – unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. The following table sets forth the fair value of our financial assets measured on a recurring basis and indicates the fair value hierarchy utilized to determine such fair value (in thousands): As of June 30, 2023 Level 1 Level 2 Level 3 Total Assets: Money market funds $ 20 $ — $ — $ 20 Cash in savings account — — — 3,886 Cash in checking account — — — 399 Total cash and cash equivalents $ 20 $ — $ — $ 4,305 As of December 31, 2022 Level 1 Level 2 Level 3 Total Assets: Money market funds $ 6,893 $ — $ — $ 6,893 Cash in checking account — — — 470 Total cash and cash equivalents $ 6,893 $ — $ — $ 7,363

Note 4 - Property and Equipment

Note 4 - Property and Equipment, Net	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Property, Plant and Equipment Disclosure [Text Block]	(4) Property and Equipment, Net Property and equipment, net consisted of the following (in thousands): June 30, December 31, 2023 2022 Computer equipment and software $ 174 $ 161 Laboratory and manufacturing equipment 574 575 Furniture and fixtures 27 27 Leasehold improvements 26 26 Property and equipment, gross 801 789 Less accumulated depreciation (662 ) (619 ) Property and equipment, net $ 139 $ 170 Depreciation expense totaled $21,000 and $43,000 for the three and six months ended June 30, 2023, respectively. Depreciation expense totaled $16,000 and $32,000 for the three and six months ended June 30, 2022, respectively.

Note 5 - Operating Lease Right-

Note 5 - Operating Lease Right-of-use Asset, Net	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Lessee, Operating Leases [Text Block]	(5) Operating Lease Right-of-Use Asset, Net In December 2021, we entered into a lease related to a property lease for our laboratory and corporate offices, which expires in January 2027, with an option for us to extend a further 36 months after expiration. Our lease agreements do not contain any material residual guarantees or material restrictive covenants. We determine if an arrangement is a lease at inception by assessing whether it conveys the right to control the use of an identified asset for a period of time in exchange for consideration. Right-of-use (ROU) assets and lease liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. The Company’s lease does not provide an implicit rate. We used an adjusted historical incremental borrowing rate, based on the information available at the approximate lease commencement date, to determine the present value of lease payments. Variable rent expense is made up of expenses for common area maintenance and shared utilities and were not included in the determination of the present value of lease payments. We have no finance leases. Our lease expense was $120,000 and $241,000 for the three and six months ended June 30, 2023, respectively. Our lease expense for the three and six months ended June 30, 2022 was $120,000 and $241,000, respectively. The cash paid under the operating lease for base rent for the three and six months ended June 30, 2023 was $118,000 and $236,000, respectively. The cash paid under the operating lease for base rent for the three and six months ended June 30, 2022 was $76,000 and $173,000, respectively. On June 30, 2023, the weighted average remaining lease term was 3.59 years, and the weighted average discount rate was 10.74%. Future minimum lease payments under the operating lease as of June 30, 2023 were as follows (in thousands): Remainder of 2023 $ 236 2024 485 2025 499 2026 514 2027 44 Total undiscounted lease payments $ 1,778 Less imputed interest 300 Total operating lease liabilities $ 1,478

Note 6 - Accrued Expenses and O

Note 6 - Accrued Expenses and Other Current Liabilities	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Accrued Liabilities and Other Current Liabilities Disclosure [Text Block]	(6) Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following (in thousands): June 30, December 31, 2023 2022 Accrued expenses $ 111 $ 157 Accrued salaries and employee benefits 715 899 Accrued clinical trial costs 821 548 Grant liability 501 534 Customer deposits 90 90 Payable to related party 19 18 Total $ 2,257 $ 2,246

Note 7 - Stockholders' Equity

Note 7 - Stockholders' Equity	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Equity [Text Block]	(7) Stockholders Equity Warrants Number of Weighted Common Stock Average Warrants Exercise Price Balance as of December 31, 2022 2,424,724 $ 6.36 Warrants for common stock sold — — Warrants for common stock exercised — — Balance as of June 30, 2023 2,424,724 $ 6.36 June 2023 Financing - Cantor Fitzgerald Sales agreement - During the three and six months ended June 30, 2023, we sold 28,599 and 134,840 shares of common stock under the ATM Offering at then-market prices for total gross proceeds of approximately $58,000 and $302,000, with net issuance costs of approximately $29,000 and $42,000, respectively. During both the three and six months ended June 30, 2022, we sold 575,000 shares of common stock under the ATM Offering at then-market prices for total gross proceeds of approximately $1.5 million, with net issuance costs of approximately $232,000. Lincoln Park Capital stock purchase agreement - Pursuant to the Purchase Agreement in March 2021, Lincoln Park purchased 373,832 shares of common stock, at a price of $5.35 per share, for a total gross purchase price of $2 million (Initial Purchase) and we issued 80,000 shares of common stock as commitment shares, which included 5,000 commitment shares issued on a pro rata basis for the initial $2 million purchase. As of June 30, 2023, we had not sold any common stock to Lincoln Park under the Purchase Agreement other than the Initial Purchase. On June 30, 2023, we provided notice to Lincoln Park of our election to terminate the Purchase Agreement. Following such termination, which was effective July 3, 2023, we may not sell any further shares of our common stock under the Purchase Agreement.

Note 8 - Share-based Compensati

Note 8 - Share-based Compensation	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Share-Based Payment Arrangement [Text Block]	(8) Share-Based Compensation The share-based compensation expense is recorded in research and development, and selling, general and administrative expenses based on the employee's or non-employee’s respective function. No share-based compensation was capitalized during the periods presented. Share-based compensation expense for the three and six months ended June 30, 2023 and 2022 was recorded as follows (in thousands): Three months ended Six months ended June 30, June 30, 2023 2022 2023 2022 Research and development $ 134 $ 130 $ 273 $ 257 Selling, general and administrative 183 174 322 366 Total share-based compensation $ 317 $ 304 $ 595 $ 623 The following table summarizes the activity of stock options and related information: Options outstanding Number of shares Weighted average exercise price Weighted average remaining contractual term (years) Aggregate intrinsic value (in thousands) Balance, December 31, 2022 2,182,708 $ 4.04 7.5 $ 343 Stock options granted 543,513 1.69 Stock options exercised (199 ) 1.49 Stock options forfeited (119,941 ) 2.36 Balance, June 30, 2023 2,606,081 $ 3.63 7.3 $ 1,189 Exercisable, June 30, 2023 1,443,515 $ 4.83 6.0 $ 315 Unrecognized share-based compensation for employee and nonemployee options granted through June 30, 2023 is approximately $2.1 million to be recognized over a remaining weighted average service period of 2.7 years. Share-Based Compensation (RSUs) The following summarizes the activity of non-vested RSUs: Weighted average grant date Number of fair value shares per share Balance, December 31, 2022 21,526 $ 4.33 RSUs granted 331,552 1.70 RSUs released (241,197 ) 1.93 RSUs forfeited (111,881 ) 1.70 Balance, June 30, 2023 — $ n/a RSUs vested and settled are converted into our common stock on a one-for-one basis. RSUs are generally subject to forfeiture if employment terminates prior to the release of vesting restrictions. The related compensation expense, which is based on the grant date fair value of our common stock multiplied by the number of units granted, is recognized ratably over the period during which the vesting restrictions lapse. Unrecognized share-based compensation for employee and nonemployee RSUs granted through June 30, 2023 was $0.

Note 9 - Net Loss Per Share

Note 9 - Net Loss Per Share	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Earnings Per Share [Text Block]	(9) Net Loss per Share Basic net loss per share is calculated by dividing the net loss by the weighted average number of shares of common stock outstanding and fully vested restricted stock units. Diluted net loss per share is computed by dividing the net loss by the weighted-average number of common share equivalents outstanding for the period determined using the treasury-stock method. Common stock equivalents are comprised of unvested restricted stock units, warrants to purchase common stock and options outstanding under the stock option plans. For all periods presented, there is no difference in the number of shares used to calculate basic and diluted shares outstanding since the effects of potentially dilutive securities are antidilutive due to the net loss position. The following outstanding common stock equivalents were excluded from the computation of diluted net loss per share for the periods presented because including them would have been antidilutive: June 30, 2023 2022 Stock options to purchase common stock 2,606,081 2,060,836 Unvested restricted stock units — 2,734 Common stock warrants 2,424,724 2,424,724 Total 5,030,805 4,488,294

Note 10 - Income Taxes

Note 10 - Income Taxes	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Income Tax Disclosure [Text Block]	(10) Income Taxes During the three and six months ended June 30, 2023 and 2022, there was no As of June 30, 2023, we retain a full valuation allowance on our deferred tax assets in all jurisdictions. The realization of our deferred tax assets depends primarily on our ability to generate future taxable income which is uncertain. We do not believe that our deferred tax assets are realizable on a more-likely-than-not basis; therefore, the net deferred tax assets have been fully offset by a valuation allowance.

Note 11 - Related Party Transac

Note 11 - Related Party Transactions	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Related Party Transactions Disclosure [Text Block]	(11) Related Party Transactions On April 9, 2020, we entered into a Litigation Funding Agreement (Funding Agreement) with BSLF, L.L.C. (Funder), an entity owned and controlled by Andrew Blank, Chair of BioCardia’s board of directors, for the purpose of funding our legal proceedings and any and all claims, actions and/or proceedings relating to or arising from the case captioned Boston Scientific Corp., et al., v. BioCardia Inc., Case No. 3:19-05645-VC, U.S.D.C., N. D. Cal (the Litigation). On April 12, 2021, all parties to the Litigation entered into a confidential settlement agreement and all claims were dismissed. In March 2022, we entered into settlement agreements with our litigation service providers and the Funder to terminate the Funding Agreement and conclude on all remaining matters thereunder (the Litigation Funding Settlement). Under the terms of the confidential agreements, litigation and corporate counsel provided credits and refunds of legal fees totaling $688,000, which offset the amounts owed to us by the Funder under the Funding Agreement, and provided up to $300,000 in future discounts on legal services. As a result of the Litigation Funding Settlement, we will remit the discounts, as received, to the Funder on a quarterly basis. During the three and six months ended June 30, 2023, we received discounts totaling $20,000 and $53,000, respectively. During the three and six months ended June 30, 2022, we received discounts totaling $43,000 and $47,000, respectively. As of June 30, 2023 and December 31, 2022, we recorded a related party payable for discounts owed to the Funder in accrued expenses and other current liabilities of $19,000 and $18,000, respectively. As of June 30, 2023, up to $168,455 future potential discounts are due to the Funder.

Note 12 - Contingencies and Unc

Note 12 - Contingencies and Uncertainties	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Contingencies Disclosure [Text Block]	(12) Contingencies and Uncertainties Contingencies Uncertainties

Significant Accounting Policies

Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2023
Accounting Policies [Abstract]
Basis of Accounting, Policy [Policy Text Block]	(a) Basis of Preparation The accompanying condensed consolidated balance sheets, statements of operations, stockholders’ equity, and cash flows as of June 30, 2023, and for the three and six months ended June 30, 2023 and 2022 are unaudited. The condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (U.S. GAAP) and applicable rules and regulations of the Securities and Exchange Commission (SEC) for interim financial information and on a basis consistent with the annual financial statements and, in the opinion of management, reflect all adjustments which include only normal recurring adjustments, necessary to present fairly its financial position as of June 30, 2023, 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. The results for the three and six months ended June 30, 2023 are not necessarily indicative of the results to be expected for the year ended December 31, 2023 or for any other interim period or for any other future year. These condensed consolidated financial statements should be read in conjunction with the audited financial statements and related notes included in our Annual Report on Form 10-K for the year ended December 31, 2022, filed with the SEC on March 29, 2023.
Going Concern and Liquidity [Policy Text Block]	(b) Liquidity Going Concern We have incurred net losses and negative cash flows from operations since our inception and had an accumulated deficit of approximately $147.5 million as of June 30, 2023. Management expects operating losses and negative cash flows to continue through at least the next several years. We expect to incur increasing costs as we advance our trials and development activities. Therefore, absent additional funding, management believes cash and cash equivalents of $4.3 million as of June 30, 2023 are not sufficient to fund the Company’s planned expenditures and meet its obligations beyond the fourth quarter of 2023. These factors raise substantial doubt about our ability to continue as a going concern beyond one year from the date these financial statements are issued. The financial statements do not include any adjustments that might result from the outcome of this uncertainty. Our ability to continue as a going concern and to continue further development of our therapeutic candidates beyond the fourth quarter of 2023 will require us to raise additional capital. We plan to raise additional capital, potentially including debt and equity arrangements, to finance our future operations. While management believes this plan to raise additional funds will alleviate the conditions that raise substantial doubt, these plans are not entirely within its control and cannot be assessed as being probable of occurring. If adequate funds are not available, we may be required to reduce operating expenses, delay or reduce the scope of our product development programs, obtain funds through arrangements with others that may require us to relinquish rights to certain of our technologies or products that we would otherwise seek to develop or commercialize, or cease operations.
Use of Estimates, Policy [Policy Text Block]	(c) Use of Estimates The preparation of the financial statements in accordance with U.S. GAAP requires management to make certain estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ materially from those estimates. Significant items subject to such estimates and assumptions include share-based compensation, the useful lives of property and equipment, right-of-use assets and related liabilities, incremental borrowing rate, allowances for doubtful accounts and sales returns, clinical accruals and assumptions used for revenue recognition.
Consolidation, Policy [Policy Text Block]	(d) Principles of Consolidation The condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary, BioCardia Lifesciences, Inc. All intercompany accounts and transactions have been eliminated during the consolidation process.
Concentration Risk, Credit Risk, Policy [Policy Text Block]	(e) Concentration of Credit Risk Financial instruments that potentially subject us to a concentration of credit risk consist of cash and cash equivalents. Our cash at times exceeds federally insured limits of $250,000 per customer. On June 30, 2023, approximately 99% of our cash was held by one financial institution and total amounts on deposit were approximately $4.0 million in excess of FDIC insurance limits. We have not recognized any losses from credit risks on such accounts since inception. Silicon Valley Bank (SVB) was closed on March 10, 2023 by the California Department of Financial Protection and Innovation, which appointed the Federal Deposit Insurance Corporation (FDIC) as receiver. On March 12, 2023, a joint statement was issued by the Secretary of the Treasury and the Federal Reserve and the FDIC Chairman stating that all depositors would be fully protected and would have access to both insured and uninsured deposits starting March 12, 2203. The FDIC then established a bridge bank successor, Silicon Valley Bridge Bank, N.A., which quickly assumed ongoing business. On March 27, 2023, First Citizens Bank & Trust Company, a subsidiary of First Citizens BancShares, assumed all customer deposits and acquired all loans of Silicon Valley Bridge Bank from the FDIC and began operating all SVB branches. As of March 31, 2023, the Company transferred substantially all of its cash and cash equivalents from SVB to another financial institution and does not believe it will be impacted by the transition of SVB to First Citizens Bank & Trust Company.
Change to Significant Accounting Policies [Policy Text Block]	(f) Changes to Significant Accounting Policies Our significant accounting policies are described in Note 2 of the notes to the consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2022 filed March 29, 2023. There have been no changes to those policies.
New Accounting Pronouncements, Policy [Policy Text Block]	(g) Recent Accounting Pronouncements Recent accounting pronouncements issued by the Financial Accounting Standards Board (FASB), including its Emerging Issues Task Force, did not or are not believed by management to have a material impact on our financial statement presentation or disclosures.

Note 3 - Fair Value Measureme_2

Note 3 - Fair Value Measurement (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	As of June 30, 2023 Level 1 Level 2 Level 3 Total Assets: Money market funds $ 20 $ — $ — $ 20 Cash in savings account — — — 3,886 Cash in checking account — — — 399 Total cash and cash equivalents $ 20 $ — $ — $ 4,305 As of December 31, 2022 Level 1 Level 2 Level 3 Total Assets: Money market funds $ 6,893 $ — $ — $ 6,893 Cash in checking account — — — 470 Total cash and cash equivalents $ 6,893 $ — $ — $ 7,363

Note 4 - Property and Equipme_2

Note 4 - Property and Equipment, Net (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Property, Plant and Equipment [Table Text Block]	June 30, December 31, 2023 2022 Computer equipment and software $ 174 $ 161 Laboratory and manufacturing equipment 574 575 Furniture and fixtures 27 27 Leasehold improvements 26 26 Property and equipment, gross 801 789 Less accumulated depreciation (662 ) (619 ) Property and equipment, net $ 139 $ 170

Note 5 - Operating Lease Righ_2

Note 5 - Operating Lease Right-of-use Asset, Net (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]	Remainder of 2023 $ 236 2024 485 2025 499 2026 514 2027 44 Total undiscounted lease payments $ 1,778 Less imputed interest 300 Total operating lease liabilities $ 1,478

Note 6 - Accrued Expenses and_2

Note 6 - Accrued Expenses and Other Current Liabilities (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Schedule of Accrued Liabilities and Other Current Liabilities [Table Text Block]	June 30, December 31, 2023 2022 Accrued expenses $ 111 $ 157 Accrued salaries and employee benefits 715 899 Accrued clinical trial costs 821 548 Grant liability 501 534 Customer deposits 90 90 Payable to related party 19 18 Total $ 2,257 $ 2,246

Note 7 - Stockholders' Equity (

Note 7 - Stockholders' Equity (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]	Number of Weighted Common Stock Average Warrants Exercise Price Balance as of December 31, 2022 2,424,724 $ 6.36 Warrants for common stock sold — — Warrants for common stock exercised — — Balance as of June 30, 2023 2,424,724 $ 6.36

Note 8 - Share-based Compensa_2

Note 8 - Share-based Compensation (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Schedule of Share-based Compensation, Expense [Table Text Block]	Three months ended Six months ended June 30, June 30, 2023 2022 2023 2022 Research and development $ 134 $ 130 $ 273 $ 257 Selling, general and administrative 183 174 322 366 Total share-based compensation $ 317 $ 304 $ 595 $ 623
Share-Based Payment Arrangement, Option, Activity [Table Text Block]	Options outstanding Number of shares Weighted average exercise price Weighted average remaining contractual term (years) Aggregate intrinsic value (in thousands) Balance, December 31, 2022 2,182,708 $ 4.04 7.5 $ 343 Stock options granted 543,513 1.69 Stock options exercised (199 ) 1.49 Stock options forfeited (119,941 ) 2.36 Balance, June 30, 2023 2,606,081 $ 3.63 7.3 $ 1,189 Exercisable, June 30, 2023 1,443,515 $ 4.83 6.0 $ 315
Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]	Weighted average grant date Number of fair value shares per share Balance, December 31, 2022 21,526 $ 4.33 RSUs granted 331,552 1.70 RSUs released (241,197 ) 1.93 RSUs forfeited (111,881 ) 1.70 Balance, June 30, 2023 — $ n/a

Note 9 - Net Loss Per Share (Ta

Note 9 - Net Loss Per Share (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 Stock options to purchase common stock 2,606,081 2,060,836 Unvested restricted stock units — 2,734 Common stock warrants 2,424,724 2,424,724 Total 5,030,805 4,488,294

Note 2 - Significant Accounti_2

Note 2 - Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Retained Earnings (Accumulated Deficit), Total	$ (147,529)	$ (140,604)
Cash and Cash Equivalents, at Carrying Value, Total	$ 4,305	$ 7,363
Cash, Percentage Held in One Financial Institution	99%
Cash, Uninsured Amount	$ 4,000

Note 3 - Fair Value Measureme_3

Note 3 - Fair Value Measurement - Fair Value of Assets Measured on a Recurring Basis (Details) - Fair Value, Recurring [Member] - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Money market funds	$ 4,305	$ 7,363
Fair Value, Inputs, Level 1 [Member]
Money market funds	20	6,893
Fair Value, Inputs, Level 2 [Member]
Money market funds	0	0
Fair Value, Inputs, Level 3 [Member]
Money market funds	0	0
Money Market Funds [Member]
Money market funds	20	6,893
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Money market funds	20	6,893
Money Market Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Money market funds	0	0
Money Market Funds [Member] | Fair Value, Inputs, Level 3 [Member]
Money market funds	0	0
Demand Deposits [Member]
Money market funds	399	45
Demand Deposits [Member] | Fair Value, Inputs, Level 1 [Member]
Money market funds	0	0
Demand Deposits [Member] | Fair Value, Inputs, Level 2 [Member]
Money market funds	0	0
Demand Deposits [Member] | Fair Value, Inputs, Level 3 [Member]
Money market funds	0	$ 0
Savings Account [Member]
Money market funds	3,886
Savings Account [Member] | Fair Value, Inputs, Level 1 [Member]
Money market funds	0
Savings Account [Member] | Fair Value, Inputs, Level 2 [Member]
Money market funds	0
Savings Account [Member] | Fair Value, Inputs, Level 3 [Member]
Money market funds	$ 0

Note 4 - Property and Equipme_3

Note 4 - Property and Equipment, Net (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Depreciation	$ 16,000	$ 21,000	$ 32,000	$ 43,000

Note 4 - Property and Equipme_4

Note 4 - Property and Equipment, Net - Summary of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Computer equipment and software	$ 801	$ 789
Less accumulated depreciation	(662)	(619)
Property and equipment, net	139	170
Computer Equipment and Software [Member]
Computer equipment and software	174	161
Laboratory and Manufacturing Equipment [Member]
Computer equipment and software	574	575
Furniture and Fixtures [Member]
Computer equipment and software	27	27
Leasehold Improvements [Member]
Computer equipment and software	$ 26	$ 26

Note 5 - Operating Lease Righ_3

Note 5 - Operating Lease Right-of-use Asset, Net (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Operating Lease, Expense	$ 120,000	$ 120,000	$ 241,000	$ 241,000
Operating Lease, Payments	$ 118,000	$ 76,000	$ 236,000	$ 173,000
Operating Lease, Weighted Average Remaining Lease Term	3 years 7 months 2 days		3 years 7 months 2 days
Operating Lease, Weighted Average Discount Rate, Percent	10.74%		10.74%

Note 5 - Operating Lease Righ_4

Note 5 - Operating Lease Right-of-use Asset, Net - Future Minimum Lease Payments Under Operating Lease (Details) $ in Thousands	Jun. 30, 2023 USD ($)
Remainder of 2023	$ 236
2024	485
2025	499
2026	514
2027	44
Total undiscounted lease payments	1,778
Less imputed interest	300
Total operating lease liabilities	$ 1,478

Note 6 - Accrued Expenses and_3

Note 6 - Accrued Expenses and Other Current Liabilities - Summary of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Accrued expenses	$ 111	$ 157
Accrued salaries and employee benefits	715	899
Accrued clinical trial costs	821	548
Grant liability	501	534
Customer deposits	90	90
Total	2,257	2,246
Related Party [Member]
Payable to related party	$ 19	$ 18

Note 7 - Stockholders' Equity_2

Note 7 - Stockholders' Equity (Details Textual) - USD ($)					3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 21, 2023	Apr. 12, 2022	Mar. 29, 2021	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Proceeds from Issuance of Common Stock							$ 2,950,000	$ 1,519,000
Payments of Stock Issuance Costs							$ 285,000	$ 165,000
Underwriters [Member]
Stock Issued During Period, Shares, New Issues (in shares)				80,000
June 2023 Financing [Member]
Stock Issued During Period, Shares, New Issues (in shares)		1,133,141
Shares Issued, Price Per Share (in dollars per share)		$ 2.336
Proceeds from Issuance of Common Stock		$ 2,600,000
Payments of Stock Issuance Costs		$ 177,000
June 2023 Financing [Member] | Company’s Directors and Executive Officers [Member]
Stock Issued During Period, Shares, New Issues (in shares)		203,337
Sales Agreement with Cantor Fitzgerald Co (Cantor) [Member]
Stock Issued During Period, Shares, New Issues (in shares)					28,599	575,000	134,840
Proceeds from Issuance of Common Stock					$ 58,000	$ 1,500,000	$ 302,000
Payments of Stock Issuance Costs					$ 29,000	$ 232,000	$ 42,000
Sale of Stock, Aggregate Value, Maximum	$ 8,400,000		$ 10,500,000
Accrued Sales Commission, Current, Percentage			3%
Purchase Agreement with Lincoln Park [Member]
Stock Issued During Period, Shares, New Issues (in shares)				373,832
Shares Issued, Price Per Share (in dollars per share)				$ 5.35
Proceeds from Issuance of Common Stock				$ 2,000,000
Sale of Stock, Aggregate Value, Maximum				$ 20,000,000
Stock Issuable, Commitment Shares on Pro Rata Basis				5,000

Note 7 - Stockholders' Equity -

Note 7 - Stockholders' Equity - Warrants (Details)	6 Months Ended
	Jun. 30, 2023 $ / shares shares
Balance , number of common stock warrants (in shares) | shares	2,424,724
Balance, weighted average exercise price (in dollars per share) | $ / shares	$ 6.36
Warrants for common stock sold , number of common stock warrants (in shares) | shares	0
Warrants for common stock sold, weighted average exercise price (in dollars per share) | $ / shares	$ 0
Warrants for common stock exercised , number of common stock warrants (in shares) | shares	0
Warrants for common stock exercised, weighted average exercise price (in dollars per share) | $ / shares	$ 0
Balance , number of common stock warrants (in shares) | shares	2,424,724
Balance as, weighted average exercise price (in dollars per share) | $ / shares	$ 6.36

Note 8 - Share-based Compensa_3

Note 8 - Share-based Compensation (Details Textual) $ in Thousands	6 Months Ended
	Jun. 30, 2023 USD ($)
Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 0
Employees, Non-employees and Non-employee Directors [Member]
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	$ 2,100
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	2 years 8 months 12 days

Note 8 - Share-based Compensa_4

Note 8 - Share-based Compensation - Share-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Total share-based compensation	$ 317	$ 304	$ 595	$ 623
Research and Development Expense [Member]
Total share-based compensation	134	130	273	257
Selling, General and Administrative Expenses [Member]
Total share-based compensation	$ 183	$ 174	$ 322	$ 366

Note 8 - Share-based Compensa_5

Note 8 - Share-based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Balance, number of shares (in shares)	2,182,708
Balance, weighted average exercise price (in dollars per share)	$ 4.04
Balance, weighted average remaining contractual term (Year)	7 years 3 months 18 days	7 years 6 months
Balance, aggregate intrinsic value	$ 1,189	$ 343
Stock options granted, number of shares (in shares)	543,513
Stock options granted, weighted average exercise price (in dollars per share)	$ 1.69
Stock options exercised, number of shares (in shares)	(199)
Stock options exercised, weighted average exercise price (in dollars per share)	$ 1.49
Stock options forfeited, number of shares (in shares)	(119,941)
Stock options forfeited, weighted average exercise price (in dollars per share)	$ 2.36
Balance, number of shares (in shares)	2,606,081	2,182,708
Balance, weighted average exercise price (in dollars per share)	$ 3.63	$ 4.04
Exercisable, number of shares (in shares)	1,443,515
Exercisable, weighted average exercise price (in dollars per share)	$ 4.83
Exercisable, weighted average remaining contractual term (Year)	6 years
Exercisable, aggregate intrinsic value	$ 315

Note 9 - Share-based Compensati

Note 9 - Share-based Compensation - Summary of Non-vested RSUs (Details) - $ / shares	6 Months Ended
	Jun. 30, 2023	Jan. 01, 2023
RSUs granted, weighted average grant date fair value per share (in dollars per share)	$ 1.70
RSUs released, weighted average grant date fair value per share (in dollars per share)	1.93
RSUs forfeited, weighted average grant date fair value per share (in dollars per share)	$ 1.70
Restricted Stock Units (RSUs) [Member]
Balance, number of shares (in shares)	21,526
Balance, weighted average grant date fair value per share (in dollars per share)		$ 4.33
RSUs granted, number of shares (in shares)	331,552
RSUs released, number of shares (in shares)	(241,197)
RSUs forfeited, number of shares (in shares)	(111,881)
Balance, number of shares (in shares)	0

Note 9 - Net Loss Per Share - A

Note 9 - Net Loss Per Share - Anti-dilutive Securities (Details) - shares	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Antidilutive securities (in shares)	5,030,805	4,488,294
Share-Based Payment Arrangement, Option [Member]
Antidilutive securities (in shares)	2,606,081	2,060,836
Restricted Stock Units (RSUs) [Member]
Antidilutive securities (in shares)	0	2,734
Warrant [Member]
Antidilutive securities (in shares)	2,424,724	2,424,724

Note 10 - Income Taxes (Details

Note 10 - Income Taxes (Details Textual) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Income Tax Expense (Benefit)	$ 0	$ 0

Note 11 - Related Party Trans_2

Note 11 - Related Party Transactions (Details Textual) - Funding Agreement [Member] - BSLF, L.L.C. [Member] - USD ($)	1 Months Ended		3 Months Ended		6 Months Ended
	Mar. 31, 2022	Mar. 29, 2022	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Legal Fees	$ 688,000
Maximum Discount on Legal Service		$ 300,000
Litigation Service, Expense			$ 20,000	$ 43,000	$ 53,000	$ 47,000
Other Liabilities, Current			19,000		19,000		$ 18,000
Loss Contingency Accrual			$ 168,455		$ 168,455

Note 12 - Contingencies and U_2

Note 12 - Contingencies and Uncertainties (Details Textual)	Jun. 30, 2023 USD ($)
BSLF, L.L.C. [Member] | Funding Agreement [Member]
Loss Contingency Accrual	$ 168,455