| Significant Accounting Policies (Policies) | 12 Months Ended |
| Dec. 31, 2023 |
| Accounting Policies [Abstract] | |
| Basis of Accounting, Policy [Policy Text Block] | (a)
Basis of Presentation and Consolidation These consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (U.S. GAAP) and include all adjustments necessary for the fair presentation of our financial position for the periods presented. The consolidated financial statements include the accounts of the Company and its wholly owned subsidiary, BioCardia Lifesciences, Inc. All material intercompany accounts and transactions have been eliminated during the consolidation process. |
| 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 $152.2 million as of December 31, 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 $1.1 million as of December 31, 2023 are not sufficient to fund our planned expenditures and meet our obligations beyond the second quarter of 2024. 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 second quarter of 2024 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. |
| Concentration Risk, Credit Risk, Policy [Policy Text Block] | (e)
Concentration of Credit Risk Financial instruments that potentially subject the Company 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 December 31, 2023, approximately 99% of our cash and cash equivalents were held by one financial institution and total amounts on deposit were approximately $0.8 million in excess of FDIC insurance limits. We have not recognized any losses from credit risks on such accounts since inception. |
| Accounts Receivable [Policy Text Block] | (f)
Accounts Receivable and Allowance for Doubtful Accounts Accounts receivable are recorded at the invoiced amount and do not bear interest. We consider the creditworthiness of our customers but do not require collateral in advance of a sale. Each reporting period, we evaluate the collectability of outstanding receivable balances and record an allowance for doubtful accounts representing an estimate of current expected credit loss. The estimate is based on our historical write-off experience, customer creditworthiness, facts, and circumstances specific to outstanding balances and payment terms. Account balances are charged off against the allowance after all means of collection have been exhausted and the potential for recovery is considered remote. The allowance for doubtful accounts was $34,000 and $11,000 as of December 31, 2023 and 2022, respectively. |
| Property, Plant and Equipment, Policy [Policy Text Block] | (g)
Property and Equipment, Net Property and equipment, net, are carried at cost less accumulated depreciation. Depreciation is calculated using the straight-line method over the estimated useful lives of the related assets, as described in the table below. Maintenance and repairs are expensed as incurred. When assets are retired or otherwise disposed of, the cost and the related accumulated depreciation and amortization are removed from the accounts and any resulting gain or loss is reflected in the accompanying consolidated statements of operations.
Asset
Estimated useful lives (in years)
Computer equipment and software 3
Laboratory and manufacturing equipment 3
Furniture and fixtures 3
Leasehold improvements
5 or lease term, if shorter |
| Lessee, Leases [Policy Text Block] | (h)
Right-of-Use Assets Operating lease right-of-use asset and liabilities We recognize lease liabilities at the applicable lease commencement date based on the present value of the lease payments required to be paid over the lease term. Variable lease payments are expensed as incurred and are not included in the computation of the lease liability. The lease liability discount rate is generally our incremental borrowing rate unless the lessor’s rate implicit in the lease is readily determinable, in which case the lessor’s implicit rate is used. We recognize our ROU assets at the applicable lease commencement date. The ROU asset equals the carrying amount of the related lease liability, adjusted for any lease payments made prior to lease commencement and lease incentives provided by the lessor, if any. We reduce a ROU asset, and the periodic reduction is the difference between the straight-line total lease cost for the period (including reduction of initial direct costs) and the periodic accretion of the lease liability using the effective interest method. Our lease terms may include options to extend or terminate the lease when it is reasonably certain that it will exercise any such options. Operating lease cost for lease payments is recognized on a straight-line basis over the lease term. Our lease contracts often include lease and non-lease components. We have elected the practical expedient offered by the standard to not separate lease from non-lease components and account for them as a single lease component. We have elected not to recognize ROU assets and lease liabilities for leases with a term of twelve months or less. Lease cost for short-term leases is recognized on a straight-line basis over the lease term. |
| Property, Plant and Equipment, Impairment [Policy Text Block] | (i)
Long-lived Assets Impairment assessment of long-lived assets |
| Clinical Trial Accruals, Policy [Policy Text Block] | (j)
Clinical Trial Accruals As part of the process of preparing its consolidated financial statements, we are required to estimate our expenses resulting from its obligations under contracts with vendors and consultants and clinical site agreements in connection with conducting clinical trials. The financial terms of these contracts are subject to negotiation and may result in payment flows that do not match the periods over which materials or services are provided by the vendor under the contracts. Our objective is to reflect the clinical trial expenses in our consolidated financial statements by matching those expenses with the period in which the services and efforts are expended. Our accounts for these expenses according to the progress of the trial as measured by patient progression and the timing of various aspects of the trial. We make estimates of our accrued expenses as of each balance sheet date in our consolidated financial statements based on the facts and circumstances known at that time. Although, we do not expect our estimates to be materially different from amounts actually incurred, our understanding of the status and timing of services relative to the actual status and timing of services performed may vary and may result in reported amounts that differ from the actual amounts incurred. |
| Revenue [Policy Text Block] | (k)
Revenue Recognition Net product revenue Collaboration agreement revenue In determining the appropriate amount of revenue to be recognized as it fulfills its obligations under each of our agreements, we perform the following steps: (i) identification of the promised goods or services in the contract; (ii) determination of whether the promised goods or services are performance obligations, including whether they are distinct in the context of the contract; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations; and (v) recognition of revenue when (or as) we satisfy each performance obligation. As part of the accounting for these arrangements, we must develop assumptions that require judgment to determine the stand-alone selling price for each performance obligation identified in the contract. We use key assumptions to determine the stand-alone selling price, which may include forecasted revenues, development timelines, reimbursement rates for personnel costs, discount rates and probabilities of technical and regulatory success. This evaluation is subjective and requires us to make judgments about the promised goods and services and whether those goods and services are separable from other aspects of the contract. Further, determining the stand-alone selling price for performance obligations requires significant judgment, and when an observable price of a promised good or service is not readily available, we consider relevant assumptions to estimate the stand-alone selling price, including, as applicable, market conditions, development timelines, probabilities of technical and regulatory success, reimbursement rates for personnel costs, forecasted revenues, potential limitations to the selling price of the product and discount rates. We apply judgment in determining whether a combined performance obligation is satisfied at a point in time or over time, and, if over time, concluding upon the appropriate method of measuring progress to be applied for purposes of recognizing revenue. We evaluate the measure of progress each reporting period and, as estimates related to the measure of progress change, related revenue recognition is adjusted accordingly. Changes in our estimated measure of progress are accounted for prospectively as a change in accounting estimate. We recognize collaboration revenue by measuring the progress toward complete satisfaction of the performance obligation using an input measure. We will re-evaluate the estimate of expected costs to satisfy the performance obligation each reporting period and make adjustments for any significant changes. Amounts received prior to satisfying the revenue recognition criteria are recorded as deferred revenue in our consolidated balance sheets. If the related performance obligation is expected to be satisfied within the next twelve Multiple contracts with the same customer - Contract costs - Contract modifications - |
| Standard Product Warranty, Policy [Policy Text Block] | (l)
Product Warranties We provide a standard warranty of serviceability on all our products for the duration of the product’s shelf life, which is two not |
| Research and Development Expense, Policy [Policy Text Block] | (m)
Research and Development We expense our research and development costs as incurred. Research and development expense include the costs of basic research activities as well as other research, engineering, and technical effort required to develop new products or services or make significant improvement to an existing product or manufacturing process. Research and development costs also include pre-approval regulatory and clinical trial expenses and support costs for collaborative partnering programs wherein we provide biotherapeutic delivery systems and customer training and support for their use in clinical trials and studies. Our research and development costs consist primarily of:
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Salaries, benefits and other personnel-related expenses, including share-based compensation;
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Fees paid for services provided by clinical research organizations, research institutions, consultants and other outside service providers;
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Costs to acquire and manufacture materials used in research and development activities and clinical trials;
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Laboratory consumables and supplies;
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Facility-related expenses allocated to research and development activities;
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Fees to collaborators to license technology; and
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Depreciation expense for equipment used for research and development and clinical purposes. |
| Compensation Related Costs, Policy [Policy Text Block] | (n)
Share-Based Compensation We measure and recognize share-based compensation expense for equity awards to employees, directors and consultants based on fair value at the grant date. We use the Black-Scholes-Merton (BSM) option pricing model to calculate fair value of our stock option grants. The compensation cost for restricted stock awards is based on the closing price of our common stock on the date of grant. Share-based compensation expense recognized in the consolidated statements of operations is based on the period the services are performed and recognized as compensation expense on a straight-line basis over the requisite service period. We account for forfeitures as they occur. Measurement of non-employee awards - The measurement of equity-classified non-employee awards is fixed at the grant date, and we may use the expected term to measure non-employee options or elect to use the contractual term as the expected term, on an award-by-award basis. This differs from the guidance in Accounting Standards Codification (ASC) 505-50 that requires the use of the contractual term. We recognize forfeitures of non-employee awards as they occur. The BSM option pricing model requires the input of subjective assumptions, including the risk-free interest rate, the expected volatility in the value of our common stock, dividend yield, and the expected term of the option. These estimates involve inherent uncertainties and the application of management’s judgment. If factors change and different assumptions are used, the share-based compensation expense could be materially different in the future. These assumptions are estimated as follows: Risk-free Interest Rate The risk-free interest rate assumption is based on the zero-coupon U.S. Treasury instruments appropriate for the expected term of the stock option grants. Expected Volatility Beginning in 2022, we base the volatility assumption on our own historical data. Prior to 2022, we had limited historical data of our own to determine expected volatility, and as such, based the volatility assumption on a combined weighted average of our own historical data and that of a selected peer group. The peer group was developed based on companies in the biotechnology and medical device industries whose shares are publicly traded. Expected Term The expected term represents the period of time that options are expected to be outstanding. As we do not have sufficient historical experience for determining the expected term of the stock options awards granted, the expected life is determined using the simplified method, which is an average of the contractual terms of the option and our ordinary vesting period. Dividend Yield We have no history or expectation of paying cash dividends on our common stock, hence dividend yield is zero for all periods presented. |
| Income Tax, Policy [Policy Text Block] | (o)
Income Taxes We account for income taxes based on the asset and liability method whereby deferred tax asset and liability account balances are determined based on differences between the financial reporting and tax bases of assets, liabilities, operating loss and tax credit carryforwards. We measure deferred tax assets and liabilities using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. A valuation allowance is provided when it is more likely than not that some portion or all of the deferred tax assets will not be realized. In evaluating the ability to recover our deferred income tax assets, we consider all available positive and negative evidence, including our operating results, forecasts of future taxable income, and ongoing tax planning. In the event we were to determine that we would be able to realize our deferred tax assets in the future in excess of their net recorded amount, we would make an adjustment to the valuation allowance, which would reduce the provision for income taxes. Conversely, in the event that all or part of the net deferred tax assets are determined not to be realizable in the future, an adjustment to the valuation allowance would be charged to earnings in the period such determination is made. We recognize and measure benefits for uncertain tax positions using a two-step approach. The first step is to evaluate the tax position taken or expected to be taken in a tax return by determining if the weight of available evidence indicates that it is more likely than not that the tax position will be sustained upon audit, including resolution of any related appeals or litigation processes. For tax positions that are more likely than not to be sustained upon audit, the second step is to measure the tax benefit as the largest amount that is more than 50% likely to be realized upon settlement. Significant judgment is required to evaluate uncertain tax positions. We evaluate our uncertain tax positions quarterly. Evaluations are based upon a number of factors, including the technical merits of the tax position, changes in facts or circumstances, changes in tax law, interactions with tax authorities during the course of audits, and effective settlement of audit issues. Our policy is to recognize interest and penalties related to unrecognized tax benefits as a component of income tax expense in the consolidated statements of operations and accrued interest and penalties within accrued expenses and other current liabilities in the consolidated balance sheets. No such interest and penalties have been recorded to date. |
| Fair Value of Financial Instruments, Policy [Policy Text Block] | (p)
Fair Value of Financial Instruments We apply fair value accounting for all financial assets and liabilities and nonfinancial assets and liabilities that are required to be recognized or disclosed at fair value in the consolidated financial statements. We define fair value as the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Where observable prices or inputs are not available, valuation models are applied. These valuation techniques involve some level of management estimation and judgment, the degree of which is dependent on the price transparency for the instruments or market and the instruments complexity. Our financial assets and liabilities consist principally of cash and cash equivalents, accounts receivable, accounts payable and accrued expenses and other current liabilities. The fair value of our cash equivalents is determined based on quoted prices in active markets for identical assets. Cash in our operating bank accounts represents the difference between cash in the money market accounts and total cash and cash equivalents reported on the consolidated balance sheets. The recorded values of our accounts receivable, accounts payable and accrued expenses and other current liabilities approximate their current fair values due to the relatively short-term nature of these accounts. |
| Earnings Per Share, Policy [Policy Text Block] | (q)
Net Loss per Share We calculate basic net loss per share by dividing the net loss by the weighted average number of shares of common stock outstanding. 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 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. |
| New Accounting Pronouncements, Policy [Policy Text Block] | (r)
Recent Accounting Pronouncements Recent accounting pronouncements issued by the Financial Accounting Standards Board, including its Emerging Issues Task Force, and the American Institute of Certified Public Accountants did not or are not believed by management to have a material impact on our financial statement presentation or disclosures. |
