0001069530-21-000050 | 10-Q | XBRL Viewer

Document And Entity Information - shares	9 Months Ended
Document And Entity Information - shares	Sep. 30, 2021	Nov. 10, 2021
Document And Entity Information [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Fiscal Period Focus	Q3
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	000-29959
Entity Registrant Name	Cassava Sciences, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	91-1911336
Entity Address, Address Line One	7801 N. Capital of Texas Highway
Entity Address, Address Line Two	Suite 260
Entity Address, City or Town	Austin
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	78731
City Area Code	512
Local Phone Number	501-2444
Title of 12(b) Security	Common Stock, $0.001 par value
Trading Symbol	SAVA
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		40,016,792
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Entity Central Index Key	0001069530

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 241,524	$ 93,506
Prepaid expenses and other current assets	10,391	488
Total current assets	251,915	93,994
Operating lease right-of-use assets	231	295
Property and equipment, net	20,695	11
Intangible assets, net	1,209
Other assets	199
Total assets	274,249	94,300
Current liabilities:
Accounts payable	2,345	911
Accrued development expense	3,251	719
Accrued compensation and benefits	126	83
Operating lease liabilities, current	95	58
Other current liabilities	509	94
Total current liabilities	6,326	1,865
Operating lease liabilities, non-current	164	235
Other non-current liabilities	194
Total liabilities	6,684	2,100
Commitments and contingencies (Notes 9, 11 and 13)
Stockholders' equity:
Preferred stock, $0.001 par value; 10,000,000 shares authorized, none issued and outstanding
Common stock, $0.001 par value; 120,000,000 shares authorized; 40,016,792 and 35,237,987 shares issued and outstanding at September 30, 2021 and December 31, 2020, respectively	40	35
Additional paid-in capital	460,659	267,086
Accumulated deficit	(193,134)	(174,921)
Total stockholders' equity	267,565	92,200
Total liabilities and stockholders' equity	$ 274,249	$ 94,300

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2021	Dec. 31, 2020
Condensed Consolidated Balance Sheets [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	40,016,792	35,237,987
Common stock, shares outstanding	40,016,792	35,237,987

Condensed Consolidated Statements Of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Operating expenses:
Research and development, net of grant reimbursement	$ 8,041	$ 399	$ 14,471	$ 1,534
General and administrative	1,712	1,038	3,953	2,634
Gain on sale of property and equipment				(346)
Total operating expenses	9,753	1,437	18,424	3,822
Operating loss	(9,753)	(1,437)	(18,424)	(3,822)
Interest income	15	7	35	106
Other income, net	176		176
Net loss	$ (9,562)	$ (1,430)	$ (18,213)	$ (3,716)
Net loss per share, basic and diluted	$ (0.24)	$ (0.06)	$ (0.46)	$ (0.15)
Shares used in computing net loss per share, basic and diluted	39,957	24,972	39,218	24,745

Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities:
Net loss	$ (18,213)	$ (3,716)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	1,237	750
Depreciation	131	21
Amortization of intangible assets	90
Gain on sale of property and equipment		(346)
Changes in operating assets and liabilities:
Prepaid and other assets	(10,102)	(729)
Operating lease right-of-use assets and liabilities	30
Accounts payable	1,434	12
Accrued development expense	2,532	(219)
Accrued compensation and benefits	43	22
Other current liabilities	609	(2)
Net cash used in operating activities	(22,209)	(4,207)
Cash flows from investing activities:
Purchases of property and equipment	(22,114)
Proceeds from sale of property and equipment		360
Net cash (used in) provided by investing activities	(22,114)	360
Cash flows from financing activities:
Proceeds from issuance of common stock upon exercise of stock options	1,824	256
Proceeds from issuance of common stock upon exercise of common stock warrants	692	4,584
Proceeds from registered direct offering, net of issuance costs	189,825
Net cash provided by financing activities	192,341	4,840
Net increase in cash and cash equivalents	148,018	993
Cash and cash equivalents at beginning of period	93,506	23,081
Cash and cash equivalents at end of period	$ 241,524	$ 24,074

General And Liquidity

9 Months Ended

Sep. 30, 2021

General And Liquidity [Abstract]

General And Liquidity

Note 1. General and Liquidity

Cassava Sciences, Inc. and its wholly-owned subsidiaries (collectively referred to as the “Company”) discovers and develops proprietary pharmaceutical product candidates that may offer significant improvements to patients and healthcare professionals. The Company generally focuses its discovery and product development efforts on disorders of the nervous system.

The accompanying unaudited condensed financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information and pursuant to the instructions to the Quarterly Report on Form 10-Q and Article 10 of Regulation S-X. All intercompany transactions and balances have been eliminated in consolidation. Accordingly, the condensed financial statements do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management of the Company, all adjustments, consisting of normal recurring adjustments, considered necessary for a fair presentation have been included. Operating results for the three and nine months ended September 30, 2021 are not necessarily indicative of the results that may be expected for any other interim period or for the year 2021. For further information, refer to the financial statements and footnotes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020.

Coronavirus Disease 2019 (COVID-19)

The widespread outbreak of a novel infectious disease called Coronavirus Disease 2019, or COVID-19, has not significantly impacted the Company’s operations or financial condition as of November 15, 2021. However, this pandemic has created a dynamic and uncertain situation in the national economy. The Company continues to closely monitor the latest information to make timely, informed business decisions and public disclosures regarding the potential impact of pandemic on its operations and financial condition. The scope of pandemic is unprecedented and its long-term impact on the Company’s operations and financial condition cannot be reasonably estimated at this time.

Liquidity

The Company has incurred significant net losses and negative cash flows since inception, and as a result has an accumulated deficit of $193.1 million at September 30, 2021. The Company expects its cash requirements to be significant in the future. The amount and timing of the Company’s future cash requirements will depend on regulatory and market acceptance of its product candidates and the resources it devotes to researching and developing, formulating, manufacturing, commercializing and supporting its products. The Company may seek additional funding through public or private financing in the future, if such funding is available and on terms acceptable to the Company. There are no assurances that additional financing will be available on favorable terms, or at all. However, management believes that the current working capital position will be sufficient to meet the Company’s working capital needs for at least the next 12 months.

Significant Accounting Policies

9 Months Ended

Sep. 30, 2021

Significant Accounting Policies [Abstract]

Significant Accounting Policies

Note 2. Significant Accounting Policies

Use of Estimates

The Company makes estimates and assumptions in preparing its condensed financial statements in conformity with GAAP. These estimates and assumptions affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed financial statements and the reported amount of revenue earned and expenses incurred during the reporting period. The Company evaluates its estimates on an ongoing basis, including those estimates related to manufacturing agreements and research collaborations. Actual results could differ from these estimates and assumptions.

Cash and Cash Equivalents and Concentration of Credit Risk

The Company invests in cash and cash equivalents. The Company considers highly liquid financial instruments with original maturities of three months or less to be cash equivalents. Highly liquid investments that are considered cash equivalents include money market accounts and funds, certificates of deposits, and U.S. Treasury securities. The Company maintains its cash and cash equivalents at one financial institution.

Fair Value Measurements

The Company recognizes financial instruments in accordance with the authoritative guidance on fair value measurements and disclosures for financial assets and liabilities. This guidance defines fair value, establishes a framework for measuring fair value in accordance with GAAP, and expands disclosures about fair value measurements. The guidance also establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value. These tiers include:

Level 1 includes quoted prices in active markets.

Level 2 includes significant observable inputs, such as quoted prices for identical or similar securities, or other inputs that are observable and can be corroborated by observable market data for similar securities. The Company uses market pricing and other observable market inputs obtained from third-party providers. It uses the bid price to establish fair value where a bid price is available. The Company does not have any financial instruments where the fair value is based on Level 2 inputs.

Level 3 includes unobservable inputs that are supported by little or no market activity. The Company does not have any financial instruments where the fair value is based on Level 3 inputs.

If a financial instrument uses inputs that fall in different levels of the hierarchy, the instrument will be categorized based upon the lowest level of input that is significant to the fair value calculation. The fair value of cash and cash equivalents was based on Level 1 inputs at September 30, 2021 and December 31, 2020.

Proceeds from Grants

During the three months ended September 30, 2021 and 2020, the Company received reimbursements totaling $2.0 million and $1.0 million pursuant to National Institutes of Health (“NIH”) research grants, respectively. During the nine months ended September 30, 2021 and 2020, the Company received reimbursements totaling $3.5 million and $3.4 million pursuant to NIH research grants, respectively. The Company records the proceeds from these grants as reductions to its research and development expenses.

Stock-based Compensation

The Company recognizes non-cash expense for the fair value of all stock options and other share-based awards. The Company uses the Black-Scholes option valuation model (“Black-Scholes”) to calculate the fair value of stock options, using the single-option award approach and straight-line attribution method. For all options granted, it recognizes the resulting fair value as expense on a straight-line basis over the vesting period of each respective stock option, generally four years.

The Company has granted share-based awards that vest upon achievement of certain performance criteria (“Performance Awards”). The Company multiplies the number of Performance Awards by the fair value of its common stock on the date of grant to calculate the fair value of each award. It estimates an implicit service period for achieving performance criteria for each award. The Company recognizes the resulting fair value as expense over the implicit service period when it concludes that achieving the performance criteria is probable. It periodically reviews and updates as appropriate its estimates of implicit service periods and conclusions on achieving the performance criteria. Performance Awards vest and common stock is issued upon achievement of the performance criteria.

Net Loss per Share

The Company computes basic net loss per share on the basis of the weighted-average number of common shares outstanding for the reporting period. Diluted net loss per share is computed on the basis of the weighted-average number of common shares outstanding plus potential dilutive common shares outstanding using the treasury-stock

method. Potential dilutive common shares consist of outstanding common stock options and warrants. There is no difference between the Company’s net loss and comprehensive loss.

The Company included the following in the calculation of basic and diluted net loss per share (in thousands, except per share data):



	Three months ended				Nine months ended
	September 30,				September 30,
	2021		2020		2021		2020
Numerator:
Net loss	$	(9,562)	$	(1,430)	$	(18,213)	$	(3,716)
Denominator:
Shares used in computing net loss per share, basic and diluted		39,957		24,972		39,218		24,745
Net loss per share, basic and diluted	$	(0.24)	$	(0.06)	$	(0.46)	$	(0.15)

Dilutive common stock options excluded from net loss per share, diluted		2,350		2,184		2,219		2,314
Common stock warrants excluded from net loss per share, diluted		—		838		—		838

The Company excluded common stock options and warrants outstanding from the calculation of net loss per share, diluted, because the effect of including options and warrants outstanding would have been anti-dilutive.

Fair Value of Financial Instruments

Financial instruments include accounts payable and accrued liabilities. The estimated fair value of certain financial instruments may be determined using available market information or other appropriate valuation methodologies. However, considerable judgment is required in interpreting market data to develop estimates of fair value; therefore, the estimates are not necessarily indicative of the amounts that could be realized or would be paid in a current market exchange. The effect of using different market assumptions and/or estimation methodologies may be material to the estimated fair value amounts. The carrying amounts of accounts payable and accrued liabilities are at cost, which approximates fair value due to the short maturity of those instruments.

Research Contract Costs and Accruals

The Company has entered into various research and development contracts with research institutions and other third-party vendors. These agreements are generally cancelable. Except for refundable deposits, related payments are recorded as research and development expenses as incurred. The Company records accruals for estimated ongoing research costs. When evaluating the adequacy of the accrued liabilities, the Company analyzes progress of the studies including the phase or completion of events, invoices received and contracted costs. Significant judgments and estimates are made in determining the accrued balances at the end of any reporting period. Actual results could differ from the Company’s estimates. The Company’s historical accrual estimates have not been materially different from actual costs.

Incentive Bonus Plan

In 2020, the Company established the 2020 Cash Incentive Bonus Plan (the “Plan”) to incentivize Plan participants. Awards under the Plan are accounted for as liability awards under Accounting Standards Codification (ASC) 718 “Stock-based Compensation”. The fair value of each potential Plan award will be determined once a grant date occurs and will be remeasured each reporting period. Compensation expense associated with the Plan will be recognized over the expected achievement period for each Plan award, when a Performance Condition (as defined below) is considered probable of being met. See Note 11 for further discussion of the Plan.

Leases

The Company recognizes assets and liabilities that arise from leases. For operating leases, the Company is required to recognize a right-of-use asset and a lease liability, initially measured at the present value of the lease payments during the lease term, in the condensed balance sheets. The Company elected the short-term lease recognition exemption for all leases that qualify. This means, for those leases that qualify, the Company does not

recognize right-of-use assets or lease liabilities. As the Company`s leases do not provide an implicit rate, it uses its incremental borrowing rate based on the information available at the commencement date in determining the present value of lease payments. Lease expense for lease payments is recognized on a straight-line basis over the lease term.

Property and equipment

Property and equipment is recorded at cost, net of accumulated depreciation. Depreciation is recorded using the straight-line method over the estimated useful lives of the assets. Buildings, and site improvements have estimated useful lives of 39 years and 9 years, respectively. Tenant improvements are amortized using the straight-line method over the useful lives of the improvements or the remaining term of the corresponding leases, whichever is shorter. The remaining term of the corresponding leases is approximately 2.8 years.

Property and equipment are reviewed for impairment when events or changes in circumstances indicate the carrying amount of an asset may not be recoverable. If property and equipment are considered to be impaired, an impairment loss is recognized.

Intangible assets

Acquired intangible assets are recorded at fair value at the date of acquisition and primarily consist of lease-in-place agreements and leasing commissions. Intangible assets are amortized over the estimated life of the lease-in-place agreements, which approximates 2.7 years.

Intangible assets are reviewed for impairment on an annual basis, and when there is reason to believe that their values have been diminished or impaired. If intangible assets are considered to be impaired, an impairment loss is recognized.

Income Taxes

The Company accounts for income taxes under the asset and liability method. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax balances are adjusted to reflect tax rates based on currently enacted tax laws, which will be in effect in the years in which the temporary differences are expected to reverse. The Company has accumulated significant deferred tax assets that reflect the tax effects of net operating loss and tax credit carryovers and temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. Realization of certain deferred tax assets is dependent upon future earnings. The Company is uncertain about the timing and amount of any future earnings. Accordingly, the Company offsets these deferred tax assets with a valuation allowance.

The Company accounts for uncertain tax positions in accordance with ASC 740, “Income Taxes”, which clarifies the accounting for uncertainty in tax positions. These provisions require recognition of the impact of a tax position in the Company’s condensed financial statements only if that position is more likely than not of being sustained upon examination by taxing authorities, based on the technical merits of the position. Any interest and penalties related to uncertain tax positions will be reflected as a component of income tax expense.

Prepaid And Other Assets

9 Months Ended

Sep. 30, 2021

Prepaid And Other Assets [Abstract]

Prepaid And Other Assets

Note 3. Prepaid and Other Assets

Prepaid and other assets at September 30, 2021 and December 31, 2020 consisted of the following (in thousands):


		September 30, 2021		December 31, 2020
Prepaid insurance	$	966	$	457
Contract research organization deposit		9,204		—
Other		221		31
Total prepaid expenses and other current assets	$	10,391	$	488

Real Property Acquisition

9 Months Ended

Sep. 30, 2021

Real Property Acquisition [Abstract]

Real Property Acquisition

Note 4. Real Property Acquisition

On August 4, 2021, the Company completed the all-cash purchase of a two-building office complex in Austin, Texas, which will serve as its future corporate headquarters. This property is intended to accommodate the Company’s anticipated growth and expansion of its operations in the coming years. Maintenance, physical facilities, leasing, property management and other key responsibilities related to property ownership are being outsourced to professional real-estate managers under long-term contract with the Company. The purchase price of the property was $22.0 million, including transaction costs, funded with cash on hand. The office complex measures approximately 90,000 rentable square feet. At acquisition and September 30, 2021, the property was 59% leased, before the Company’s occupancy of approximately an additional 25% of the property in 2022. The seller was an independent third party not affiliated with the Company.

The purchase was accounted for as an asset acquisition under Accounting Standards Codification (ASC) 805, Business Combinations. As all assets purchased by the Company are considered a single identifiable asset for purposes of the screen test under ASC 805 as the buildings and property improvements are attached to the land and cannot be removed without incurring significant costs and the in-place lease intangibles should be combined with the related real estate and considered a single asset. As substantially all of the fair value of the gross assets acquired are concentrated into a single identifiable asset, the Company concluded that the screen was met, and the transaction is not considered an acquisition of a business. Pursuant to the cost accumulation method as prescribed in ASC 805, the cost of the acquisition, including certain transaction costs, is allocated to the assets acquired on the basis of relative fair values. The value of acquired in-place leases is measured as the sum of lost revenues that would be incurred during a prospective lease-up period that would be necessary to achieve occupancy similar to that at the time of acquisition.

The acquisition is summarized as follows (in thousands):



	Real Property Acquisition
Land	$	3,734
Buildings		15,980
Site improvements		453
Tenant improvements		567
Total tangible assets acquired	$	20,734

Lease-in-place agreements	$	1,053
Leasing commissions and other		246
Total intangible assets	$	1,299

Consideration paid	$	22,033

The Company records the net income from building operations and leases as other income, net, as leasing is not core to the Company’s operations. Building depreciation and amortization is included in general and administrative expense. Components of other income, net, for the three and nine months ended September 30, 2021 and 2020 were as follows (in thousands):



	Three months ended				Nine months ended
	September 30,				September 30,
	2021		2020		2021		2020
Lease revenue	$	347	$	—	$	347	$	—
Property operating expenses		(171)		—		(171)		—
Other income, net	$	176	$	—	$	176	$	—

Property And Equipment

9 Months Ended

Sep. 30, 2021

Property And Equipment [Abstract]

Property And Equipment

Note 5. Property and equipment

The components of property and equipment, net, as of September 30, 2021 and December 31, 2020 were as follows (in thousands):



	September 30, ‎2021		December 31, ‎2020
Land	$	3,734	$	—
Buildings		15,980		—
Site improvements		453		—
Tenant improvements		567		—
Furniture and equipment		178		97
Gross property and equipment	$	20,912	$	97
Accumulated depreciation		(217)		(86)
Property and equipment, net	$	20,695	$	11

Intangible Assets

9 Months Ended

Sep. 30, 2021

Intangible Asset [Abstract]

Intangible Assets

Note 6. Intangible assets

The components of intangible assets, net, as of September 30, 2021 and December 31, 2020 were as follows (in thousands):



	September 30, ‎2021		December 31, ‎2020
Lease-in-place agreements	$	1,053	$	—
Leasing commissions and other		246		—
Gross intangible assets	$	1,299	$	—
Accumulated amortization		(90)		—
Intangible assets, net	$	1,209	$	—

Amortization expense for finite-lived intangible assets is expected to be as follows (in thousands):



For the year ending December 31,
2021	$	206
2022		464
2023		464
2024		165
Total amortization	$	1,299

Stockholders' Equity And Stock-Based Compensation Expense

9 Months Ended

Sep. 30, 2021

Stockholders' Equity And Stock-Based Compensation Expense [Abstract]

Stockholders' Equity And Stock-Based Compensation Expense

Note 7. Stockholders’ Equity and Stock-Based Compensation Expense

Stockholders’ Equity Activity during the Nine Months Ended September 30, 2021 and 2020

During the nine months ended September 30, 2021 and 2020, the Company’s common stock outstanding and stockholders’ equity changed as follows:


	Common Stock	Stockholders' equity ‎(in thousands)
Balance at December 31, 2019	21,841,810	$	22,099
Stock-based compensation for:
Stock options for employees	—		261
Stock options for non-employees	—		9
Proceeds from exercise of common stock warrants	2,888,092		3,613
Net loss	—		(1,150)
Balance at March 31, 2020	24,729,902	$	24,832

Stock-based compensation for:
Stock options for employees	—		249
Stock options for non-employees	—		3
Proceeds from exercise of common stock warrants	189,431		236
Net loss	—		(1,136)
Balance at June 30, 2020	24,919,333	$	24,184

Non-cash stock-based compensation for:
Stock options for employees	—		224
Stock options for non-employees	—		4
Proceeds from exercise of common stock warrants	588,235		735
Proceeds from exercise of stock options	71,105		256
Net loss	—		(1,430)
Balance at September 30, 2020	25,578,673	$	23,973


Balance at December 31, 2020	35,237,987	$	92,200
Stock-based compensation for:
Stock options for employees	—		249
Stock options for non-employees	—		1
Proceeds from exercise of common stock warrants	554,019		692
Exercise of stock options	135,015		1,746
Proceeds from registered direct offering of common stock	4,081,633		189,825
Net loss	—		(3,526)
Balance at March 31, 2021	40,008,654	$	281,187

Stock-based compensation for:
Stock options for employees	—		410
Stock options for non-employees	—		5
Exercise of stock options	3,240		3
Net loss	—		(5,125)
Balance at June 30, 2021	40,011,894	$	276,480

Stock-based compensation for:
Stock options for employees	—		24
Stock options for non-employees	—		548
Exercise of stock options	4,898		75
Net loss	—		(9,562)
Balance at September 30, 2021	40,016,792	$	267,565

2021 Registered Direct Offering

On February 12, 2021, the Company completed a common stock offering pursuant to which certain investors purchased 4,081,633 shares of common stock at a price of $49.00 per share. Net proceeds of the offering were approximately $189.8 million after deducting offering expenses.

At-the-Market Common Stock Offering

In March 2020, the Company established an at-the-market offering program (“ATM”) to sell, from time to time, shares of Company common stock having an aggregate offering price of up to $100 million in transactions pursuant to a shelf registration statement that was declared effective by the U.S. Securities and Exchange Commission (the “SEC”) on May 5, 2020. The Company is obligated to pay a commission of 3.0% of the gross proceeds from the sale of shares of common stock in the offering. The Company is not obligated to sell any shares in the offering.

There were no common stock sales under the ATM during the three and nine months ended September 30, 2021 and 2020.

Common Stock Warrants

In August 2018, the Company issued warrants to purchase up to an aggregate of 9.1 million shares of its common stock in conjunction with an offering of its common stock.

The Company did not receive any proceeds from exercise of common stock warrants during the three months ended September 30, 2021. During the three months ended September 30, 2020, the Company received proceeds of $0.7 million from the exercise of 0.6 million shares pursuant to warrants.

During the nine months ended September 30, 2021, the Company received proceeds of $0.7 million from the exercise of 0.6 million shares pursuant to warrants. During the nine months ended September 30, 2020, the Company received proceeds of $4.6 million from the exercise of 3.7 million shares pursuant to warrants.

There were no common stock warrants outstanding as of September 30, 2021.

Stock Option and Performance Award Activity in 2021

During the nine months ended September 30, 2021, stock options and unvested Performance Awards outstanding under the Company’s stock option plans changed as follows:


	Stock Options	Performance Awards
Outstanding as of December 31, 2020	2,817,504	138,055
Options granted	92,500	—
Options exercised	(241,638)	—
Options forfeited/canceled	(12,139)	—
Outstanding as of September 30, 2021	2,656,227	138,055

The weighted average exercise price of options outstanding at September 30, 2021 was $11.46. As outstanding options vest over the current remaining vesting period of 2.2 years, the Company expects to recognize stock-based compensation expense of $6.5 million. If and when outstanding Performance Awards vest, the Company will recognize stock-based compensation expense of $2.3 million over the implicit service period.

During the three months ended September 30, 2021, there were 6,644 stock options exercised. Of the stock options exercised, 1,746 stock options were net settled in satisfaction of the exercise price, with no cash proceeds received. Cash proceeds to the Company for options not net settled totaled $75,000 during the three months ended September 30, 2021.

During the nine months ended September 30, 2021, there were 241,638 stock options exercised. Of the stock options exercised, 100,485 stock options were net settled in satisfaction of the exercise price, with no cash proceeds

received. Cash proceeds to the Company for options not net settled totaled $1,824,000 during the nine months ended September 30, 2021.

During the three and nine months ended September 30, 2020, there were 71,000 stock options exercised resulting in cash proceeds to the Company totaling $256,000.

Stock-based Compensation Expense in 2021

During the three and nine months ended September 30, 2021 and 2020, the Company’s stock-based compensation expense was as follows (in thousands):



	Three months ended				Nine months ended
	September 30,				September 30,
	2021		2020		2021		2020
Research and development	$	452	$	109	$	867	$	335

General and administrative		120		119		370		415

Total stock-based compensation expense	$	572	$	228	$	1,237	$	750

2018 Equity Incentive Plan

In January 2018, the Company’s Board of Directors (the “Board”) approved the Company’s 2018 Omnibus Incentive Plan (the “2018 Plan”). The Board or a designated committee of the Board is responsible for administration of the 2018 Plan and determines the terms and conditions of each option granted, consistent with the terms of the 2018 Plan. The Company’s employees, directors, and consultants are eligible to receive awards under the 2018 Plan, including grants of stock options and Performance Awards. Share-based awards generally expire 10 years from the date of grant. The 2018 Plan provides for issuance of up to 1,000,000 shares of common stock, par value $0.001 per share, subject to adjustment as provided in the 2018 Plan.

When stock options or Performance Awards are exercised net of the exercise price and taxes, the number of shares of stock issued is reduced by the number of shares equal to the amount of taxes owed by the award recipient and that number of shares are cancelled. The Company then uses its cash to pay tax authorities the amount of statutory taxes owed by and on behalf of the award recipient.

Income Taxes

9 Months Ended

Sep. 30, 2021

Income Taxes [Abstract]

Income Taxes

Note 8. Income Taxes

The Company did not provide for income taxes during the three and nine months ended September 30, 2021, because it has projected a net loss for the full year 2021 for which any benefit will be offset by an increase in the valuation allowance. There was also no provision for income taxes for the three and nine months ended September 30, 2020.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References + Details

Commitments

9 Months Ended

Sep. 30, 2021

Commitments [Abstract]

Commitments

Note 9. Commitments

Right-of-use Asset and Liability

The Company has a non-cancelable operating lease for approximately 6,000 square feet of office space in Austin, Texas that expires on April 30, 2024. The Company also has a short-term lease agreement for an additional 3,600 square feet of office space in Austin, Texas that expires on April 30, 2022. Future lease payments as of September 30, 2021 are as follows (in thousands):


Future lease payments		2021	2022	2023	2024	Total future lease payments	Less: imputed interest		Total

Operating leases	$	25	102	107	36	270	(11)	$	259
Short-term operating lease	$	16	21	—	—	37	—	$	37

Rent expense for the three months ended September 30, 2021 and 2020 totaled $41,000 and $25,000, respectively.

Rent expense for the nine months ended September 30, 2021 and 2020 totaled $98,000 and $75,000, respectively.

Cash paid for operating lease liabilities during the three months ended September 30, 2021 and 2020 totaled $41,000 and $25,000, respectively. Cash paid for operating lease liabilities during the nine months ended September 30, 2021 and 2020 totaled $68,000 and $75,000, respectively.

Other Commitments

The Company conducts its product research and development programs through a combination of internal and collaborative programs that include, among others, arrangements with universities, contract research organizations and clinical research sites. The Company has contractual arrangements with these organizations that are cancelable. The Company’s obligations under these contracts are largely based on services performed. The Company also had non-cancellable commitments for the manufacture of simufilam totaling approximately $1.9 million at September 30, 2021.

Sale Of Property And Equipment

9 Months Ended

Sep. 30, 2021

Sale Of Property And Equipment [Abstract]

Sale Of Property And Equipment

Note 10. Sale of Property and Equipment

There were no sales of property and equipment during the three and nine months ended September 30, 2021.

There were no sales of property and equipment during the three months ended September 30, 2020. During the nine months ended September 30, 2020, the Company sold surplus manufacturing equipment to a third party and received proceeds totaling $360,000. The original cost of the property and equipment was $892,000 and accumulated depreciation was $878,000, resulting in a gain on sale of property and equipment of $346,000 during the nine months ended September 30, 2020.

2020 Cash Incentive Bonus Plan

9 Months Ended

Sep. 30, 2021

Cash Incentive Bonus Plan [Abstract]

2020 Cash Incentive Bonus Plan

Note 11. 2020 Cash Incentive Bonus Plan

In August 2020, the Board approved the Plan. The Plan was established to promote the long-term success of the Company by creating an “at-risk” cash bonus program that rewards Plan participants with additional cash compensation in lockstep with significant increases in the Company’s market capitalization. The Plan is considered “at-risk” because Plan participants will not receive a cash bonus unless the Company’s market capitalization increases significantly and certain other conditions specified in the Plan are met. Specifically, Plan participants will not be paid any cash bonuses unless (1) the Company completes a merger or acquisition transaction that constitutes a sale of ownership of the Company or its assets (a Merger Transaction) or (2) the Compensation Committee of the Board (the Compensation Committee) determines the Company has sufficient cash on hand, as defined in the Plan. Because of the inherent discretion and uncertainty regarding these requirements, the Company has concluded that a Plan grant date has not occurred as of September 30, 2021.

Plan participants will be paid all earned cash bonuses in the event of a Merger Transaction.

The Company’s market capitalization for purposes of the Plan is determined based on either (1) the Company’s closing price of one share on the Nasdaq Capital Market multiplied by the total issued and outstanding shares and options to purchase shares of the Company, or (2) the aggregate consideration payable to security holders of the Company in a Merger Transaction. This constitutes a market condition under applicable accounting guidance.

The Plan triggers a potential cash bonus each time the Company’s market capitalization increases significantly, up to a maximum $5 billion in market capitalization. The Plan specifies 14 incremental amounts between $200 million and $5 billion (each increment, a “Valuation Milestone”). Each Valuation Milestone triggers a potential cash bonus award in a pre-set amount defined in the Plan. Each Valuation Milestone must be achieved and maintained for no less than 20 consecutive trading days for Plan participants to be eligible for a potential cash bonus award. Approximately 58% of each cash bonus award associated with a Valuation Milestone is subject to adjustment and approval by the Compensation Committee. Any amounts not awarded by the Compensation Committee are no longer available for distribution.

If the Company were to exceed a $5 billion market capitalization for no less than 20 consecutive trading days, all Valuation Milestones would be deemed achieved, in which case cash bonus awards would range from a minimum of $139.1 million up to a hypothetical maximum of $322.3 million. Payment of cash bonuses is deferred until such time as (1) the Company completes a Merger Transaction, or (2) the Compensation Committee determines the Company has sufficient cash on hand to render payment (each, a “Performance Condition”), neither of which may ever occur. Accordingly, there can be no assurance that Plan participants will ever be paid a cash bonus that is awarded under the Plan, even if the Company’s market capitalization increases significantly.

The Plan is accounted for as a liability award. The fair value of each Valuation Milestone award will be determined once a grant date occurs and will be remeasured each reporting period. Compensation expense associated with the Plan will be recognized over the expected achievement period for each of the 14 Valuation Milestones, when a Performance Condition is considered probable of being met.

In October 2020, the Company achieved the first Valuation Milestone. Subsequently, the Compensation Committee approved a potential cash bonus award of $7.3 million in total for all Plan participants, subject to future satisfaction of a Performance Condition.

During the nine months ended September 30, 2021, the Company achieved 11 Valuation Milestones triggering potential Company obligations to all Plan participants from a minimum of $93.7 million up to a hypothetical maximum of $225.0 million, to be determined by the Compensation Committee. However, no compensation expense has been recorded since no grant date has occurred and no Performance Conditions are considered probable of being met. There is no continuing service requirement for Plan participants once the Compensation Committee approves a cash bonus award.

No actual cash payments were authorized or made to participants under the Plan through September 30, 2021.

Recently Issued Accounting Pronouncements	9 Months Ended
Recently Issued Accounting Pronouncements	Sep. 30, 2021
Recently Issued Accounting Pronouncements [Abstract]
Recently Issued Accounting Pronouncements	Note 12. Recently Issued Accounting Pronouncements In December 2019, the FASB issued Accounting Standards Update (“ASU”) No. 2019-12, Income Taxes (Topic 740) Simplifying Accounting for Income Taxes, as part of its initiative to reduce complexity in the accounting standards. The guidance amended certain disclosure requirements that had become redundant, outdated or superseded. Additionally, this guidance amends accounting for the interim period effects of changes in tax laws or rates, and simplifies aspects of the accounting for franchise taxes. The guidance is effective for annual periods beginning after December 15, 2020, including interim periods therein. The adoption of ASU 2019-12 in the first quarter of 2021 did not have a material impact on the Company’s condensed financial statements.

- Definition

The entire disclosure for change in accounting principle. Includes, but is not limited to, nature, reason, and method of adopting amendment to accounting standards or other change in accounting principle.

+ References

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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Contingencies

9 Months Ended

Sep. 30, 2021

Contingencies [Abstract]

Contingencies

Note 13. Contingencies

Securities Class Actions and Shareholder Derivative Action

Between August 27 and October 26, 2021, following the submission of a Citizen Petition to the U.S. Food and Drug Administration (FDA) by Labaton Sucharow LLP, four class action lawsuits were filed alleging violations of the U.S. securities laws by the Company and certain named officers. The complaints allege that various statements made by the defendants regarding simufilam were rendered materially false and misleading by the allegation contained in the Labaton Sucharow Citizen Petition. These actions were filed in the United States District Court for the Western District of Texas. The complaints seek unspecified compensatory damages and other relief on behalf of a purported class of purchasers of the Company’s securities between September 14, 2020, and August 27, 2021. The Company expects that the cases will be consolidated and that a lead plaintiff and lead counsel will be appointed and thereafter that a consolidated amended complaint will be filed. The Company believes the claims are without merit and intends to defend against these lawsuits vigorously. The Company is unable to estimate the possible loss or range of loss, if any, associated with these lawsuits.

On November 4, 2021, a related shareholder derivative action was filed, purportedly on behalf of the Company, in the United States District Court for the Western District of Texas, asserting claims under the U.S. securities laws and state fiduciary duty laws against certain named officers and the members of the Company’s board of directors. The complaint relies on the Labaton Sucharow LLP Citizen Petition and alleges, among other things, that the individual defendants exposed the Company to unspecified damages and securities law liability by causing it to make materially

false and misleading statements, in violation of the U.S. securities laws and in breach of their fiduciary duties to the Company. The derivative case seeks, among other things, to recover unspecified compensatory damages on behalf of the Company arising out of the individual defendants’ alleged wrongful conduct. Although the plaintiffs in the derivative cases does not seek relief against the Company, it has certain indemnification obligations to the individual defendants.

Significant Accounting Policies (Policy)

9 Months Ended

Sep. 30, 2021

Significant Accounting Policies [Abstract]

Use Of Estimates

Use of Estimates

Cash And Cash Equivalents And Concentration Of Credit Risk

Cash and Cash Equivalents and Concentration of Credit Risk

Fair Value Measurements

Level 1 includes quoted prices in active markets.

Level 3 includes unobservable inputs that are supported by little or no market activity. The Company does not have any financial instruments where the fair value is based on Level 3 inputs.

Proceeds From Grants

Proceeds from Grants

Stock-Based Compensation

Stock-based Compensation

Net Loss Per Share

Net Loss per Share

method. Potential dilutive common shares consist of outstanding common stock options and warrants. There is no difference between the Company’s net loss and comprehensive loss.

The Company included the following in the calculation of basic and diluted net loss per share (in thousands, except per share data):



	Three months ended				Nine months ended
	September 30,				September 30,
	2021		2020		2021		2020
Numerator:
Net loss	$	(9,562)	$	(1,430)	$	(18,213)	$	(3,716)
Denominator:
Shares used in computing net loss per share, basic and diluted		39,957		24,972		39,218		24,745
Net loss per share, basic and diluted	$	(0.24)	$	(0.06)	$	(0.46)	$	(0.15)

Dilutive common stock options excluded from net loss per share, diluted		2,350		2,184		2,219		2,314
Common stock warrants excluded from net loss per share, diluted		—		838		—		838

Fair Value Of Financial Instruments

Fair Value of Financial Instruments

Research Contract Costs And Accruals

Research Contract Costs and Accruals

Incentive Bonus Plan

Leases

Propert And Equipment

Property and equipment

Intangible Assets

Intangible assets

Income Taxes

Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2021

Significant Accounting Policies [Abstract]

Numerators And Denominators In The Calculation Of Basic And Diluted Net Loss Per Share



	Three months ended				Nine months ended
	September 30,				September 30,
	2021		2020		2021		2020
Numerator:
Net loss	$	(9,562)	$	(1,430)	$	(18,213)	$	(3,716)
Denominator:
Shares used in computing net loss per share, basic and diluted		39,957		24,972		39,218		24,745
Net loss per share, basic and diluted	$	(0.24)	$	(0.06)	$	(0.46)	$	(0.15)

Dilutive common stock options excluded from net loss per share, diluted		2,350		2,184		2,219		2,314
Common stock warrants excluded from net loss per share, diluted		—		838		—		838

Prepaid And Other Assets (Tables)

9 Months Ended

Sep. 30, 2021

Prepaid And Other Assets [Abstract]

Schedule Of Prepaid And Other Assets


		September 30, 2021		December 31, 2020
Prepaid insurance	$	966	$	457
Contract research organization deposit		9,204		—
Other		221		31
Total prepaid expenses and other current assets	$	10,391	$	488

Real Property Aquisition (Tables)

9 Months Ended

Sep. 30, 2021

Real Property Acquisition [Abstract]

Summary Of Acquisition



	Real Property Acquisition
Land	$	3,734
Buildings		15,980
Site improvements		453
Tenant improvements		567
Total tangible assets acquired	$	20,734

Lease-in-place agreements	$	1,053
Leasing commissions and other		246
Total intangible assets	$	1,299

Consideration paid	$	22,033

Components Of Other Income, Net



	Three months ended				Nine months ended
	September 30,				September 30,
	2021		2020		2021		2020
Lease revenue	$	347	$	—	$	347	$	—
Property operating expenses		(171)		—		(171)		—
Other income, net	$	176	$	—	$	176	$	—

Property And Equipment (Tables)

9 Months Ended

Sep. 30, 2021

Property And Equipment [Abstract]

Components Of Property And Equipment, Net



	September 30, ‎2021		December 31, ‎2020
Land	$	3,734	$	—
Buildings		15,980		—
Site improvements		453		—
Tenant improvements		567		—
Furniture and equipment		178		97
Gross property and equipment	$	20,912	$	97
Accumulated depreciation		(217)		(86)
Property and equipment, net	$	20,695	$	11

Intangible Assets (Tables)

9 Months Ended

Sep. 30, 2021

Intangible Asset [Abstract]

Components Of Intangible Assets, Net



	September 30, ‎2021		December 31, ‎2020
Lease-in-place agreements	$	1,053	$	—
Leasing commissions and other		246		—
Gross intangible assets	$	1,299	$	—
Accumulated amortization		(90)		—
Intangible assets, net	$	1,209	$	—

Amortization Expense For Finite-Lived Intangible Assets



For the year ending December 31,
2021	$	206
2022		464
2023		464
2024		165
Total amortization	$	1,299

Stockholders' Equity And Stock-Based Compensation Expense (Tables)

9 Months Ended

Sep. 30, 2021

Stockholders' Equity And Stock-Based Compensation Expense [Abstract]

Common Stock Outstanding And Stockholders' Equity


	Common Stock	Stockholders' equity ‎(in thousands)
Balance at December 31, 2019	21,841,810	$	22,099
Stock-based compensation for:
Stock options for employees	—		261
Stock options for non-employees	—		9
Proceeds from exercise of common stock warrants	2,888,092		3,613
Net loss	—		(1,150)
Balance at March 31, 2020	24,729,902	$	24,832

Stock-based compensation for:
Stock options for employees	—		249
Stock options for non-employees	—		3
Proceeds from exercise of common stock warrants	189,431		236
Net loss	—		(1,136)
Balance at June 30, 2020	24,919,333	$	24,184

Non-cash stock-based compensation for:
Stock options for employees	—		224
Stock options for non-employees	—		4
Proceeds from exercise of common stock warrants	588,235		735
Proceeds from exercise of stock options	71,105		256
Net loss	—		(1,430)
Balance at September 30, 2020	25,578,673	$	23,973


Balance at December 31, 2020	35,237,987	$	92,200
Stock-based compensation for:
Stock options for employees	—		249
Stock options for non-employees	—		1
Proceeds from exercise of common stock warrants	554,019		692
Exercise of stock options	135,015		1,746
Proceeds from registered direct offering of common stock	4,081,633		189,825
Net loss	—		(3,526)
Balance at March 31, 2021	40,008,654	$	281,187

Stock-based compensation for:
Stock options for employees	—		410
Stock options for non-employees	—		5
Exercise of stock options	3,240		3
Net loss	—		(5,125)
Balance at June 30, 2021	40,011,894	$	276,480

Stock-based compensation for:
Stock options for employees	—		24
Stock options for non-employees	—		548
Exercise of stock options	4,898		75
Net loss	—		(9,562)
Balance at September 30, 2021	40,016,792	$	267,565

Stock Options And Unvested Performance Award Outstanding Activity


	Stock Options	Performance Awards
Outstanding as of December 31, 2020	2,817,504	138,055
Options granted	92,500	—
Options exercised	(241,638)	—
Options forfeited/canceled	(12,139)	—
Outstanding as of September 30, 2021	2,656,227	138,055

Stock-Based Compensation Expense



	Three months ended				Nine months ended
	September 30,				September 30,
	2021		2020		2021		2020
Research and development	$	452	$	109	$	867	$	335

General and administrative		120		119		370		415

Total stock-based compensation expense	$	572	$	228	$	1,237	$	750

Commitments (Tables)

9 Months Ended

Sep. 30, 2021

Commitments [Abstract]

Future Minimum Lease Payments


Future lease payments		2021	2022	2023	2024	Total future lease payments	Less: imputed interest		Total

Operating leases	$	25	102	107	36	270	(11)	$	259
Short-term operating lease	$	16	21	—	—	37	—	$	37

General And Liquidity (Narrative) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
General And Liquidity [Abstract]
Accumulated deficit	$ 193,134	$ 174,921

Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Summary Of Significant Accounting Policies [Line Items]
Reimbursement from National Institutes of Health research grants	$ 2.0	$ 1.0	$ 3.5	$ 3.4
Vesting period of stock options			4 years
Leases-In-Place Agreements [Member]
Summary Of Significant Accounting Policies [Line Items]
Intangible assets, Estimated useful lives			2 years 8 months 12 days
Building [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, Estimated useful lives			39 years
Site Improvements [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, Estimated useful lives			9 years
Tenant Improvements [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, Estimated useful lives			2 years 9 months 18 days

Significant Accounting Policies (Numerators And Denominators In The Calculation Of Basic And Diluted Net Loss Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Numerator:
Net loss	$ (9,562)	$ (5,125)	$ (3,526)	$ (1,430)	$ (1,136)	$ (1,150)	$ (18,213)	$ (3,716)
Denominator:
Shares used in computing net loss per share, basic and diluted	39,957			24,972			39,218	24,745
Net loss per share, basic and diluted	$ (0.24)			$ (0.06)			$ (0.46)	$ (0.15)
Stock Option [Member]
Denominator:
Common stock excluded from net loss per share, diluted	2,350			2,184			2,219	2,314
Warrants [Member]
Denominator:
Common stock excluded from net loss per share, diluted				838				838

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://fasb.org/us-gaap/role/ref/legacyRef
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+ Details

Prepaid And Other Assets (Schedule Of Prepaid And Other Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Prepaid And Other Assets [Abstract]
Prepaid insurance	$ 966	$ 457
Contract research organization deposit	9,204
Other	221	31
Total prepaid expenses	$ 10,391	$ 488

Real Property Acquisition (Narrative) (Details) - Building [Member] - Austin, Texas [Member] $ in Millions	Aug. 04, 2021 USD ($) ft²
Business Acquisition [Line Items]
Purchase price \| $	$ 22.0
Rentable area \| ft²	90,000
Percentage of currently leased	59.00%
Percentage of occupying in the future	25.00%

Real Property Acquisition (Summary Of Acquisition) (Details) - Austin, Texas [Member] $ in Thousands	Aug. 04, 2021 USD ($)
Business Acquisition [Line Items]
Total tangible assets acquired	$ 20,734
Total intangible assets	1,299
Consideration paid	22,033
Land [Member]
Business Acquisition [Line Items]
Total tangible assets acquired	3,734
Building [Member]
Business Acquisition [Line Items]
Total tangible assets acquired	15,980
Site Improvements [Member]
Business Acquisition [Line Items]
Total tangible assets acquired	453
Tenant Improvements [Member]
Business Acquisition [Line Items]
Total tangible assets acquired	567
Leases-In-Place Agreements [Member]
Business Acquisition [Line Items]
Total intangible assets	1,053
Leasing Commissions And Other [Member]
Business Acquisition [Line Items]
Total intangible assets	$ 246

Real Property Acquisition (Components Of Other Income, Net) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Business Acquisition [Line Items]
Other income, net	$ 176		$ 176
Building [Member] \| Austin, Texas [Member]
Business Acquisition [Line Items]
Lease revenue	347		347
Property depreciation and amortization	(171)		(171)
Other income, net	$ 176		$ 176

Property And Equipment (Components Of Property And Equipment, Net) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020
Property, Plant and Equipment [Line Items]
Gross property and equipment	$ 20,912	$ 97	$ 892
Accumulated depreciation	(217)	(86)	$ (878)
Property and equipment, net	20,695	11
Land [Member]
Property, Plant and Equipment [Line Items]
Gross property and equipment	3,734
Building [Member]
Property, Plant and Equipment [Line Items]
Gross property and equipment	15,980
Site Improvements [Member]
Property, Plant and Equipment [Line Items]
Gross property and equipment	453
Tenant Improvements [Member]
Property, Plant and Equipment [Line Items]
Gross property and equipment	567
Furniture And Equipment [Member]
Property, Plant and Equipment [Line Items]
Gross property and equipment	$ 178	$ 97

Intangible Assets (Components Of Intangible Assets, Net) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross intangible assets	$ 1,299
Accumulated amortization	(90)
Intangible assets, net	1,209
Leases-In-Place Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross intangible assets	1,053
Leasing Commissions And Other [Member]
Finite-Lived Intangible Assets [Line Items]
Gross intangible assets	$ 246

Intangible Assets (Amortization Expense For Finite-Lived Intangible Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Intangible Asset [Abstract]
2021	$ 206
2022	464
2023	464
2024	165
Total amortization	$ 1,299

Stockholders' Equity And Stock-Based Compensation Expense (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended		3 Months Ended				9 Months Ended
	Feb. 12, 2021	Jan. 31, 2018	Mar. 31, 2020	Aug. 31, 2018	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	May 05, 2020
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock options exercised					4,898	3,240	135,015	71,105
Proceeds from issuance of common stock upon exercise of stock options									$ 1,824	$ 256
Proceeds from offering							$ 189,825		189,825
Proceeds from exercise of warrants									$ 692	4,584
Vesting period of stock options									4 years
Stock-based compensation expense					$ 572			$ 228	$ 1,237	$ 750
Par value per share					$ 0.001				$ 0.001		$ 0.001
2021 Registered Direct Offering [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Number of shares issued	4,081,633
Price per share	$ 49.00
Proceeds from offering	$ 189,800
ATM [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Percentage of commission in ATM offering												3.00%
Number of shares issued					0			0	0	0
ATM [Member] \| Maximum [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Aggregate offering price			$ 100,000
Common Stock Warrants [Member] \| Warrants [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Number of shares issued				9,100,000
Proceeds from exercise of warrants					$ 0			$ 700	$ 700	$ 4,600
Number of warrants exercised								600,000	600,000	3,700,000
Number of warrants outstanding					0				0
2018 Equity Incentive Plan [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Expiration period		10 years
Par value per share		$ 0.001
2018 Equity Incentive Plan [Member] \| Maximum [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Shares issued		1,000,000
Stock Option [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock options exercised					6,644			71,000	241,638	71,000
Proceeds from issuance of common stock upon exercise of stock options					$ 75			$ 256	$ 1,824	$ 256
Stock options exercised, net settled in satisfaction of the exercise price					1,746				100,485
Proceeds from stock options exercised net settled in satisfaction of the exercise price					$ 0				$ 0
Stock Option [Member] \| Stock Option And Performance Award [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Weighted average exercise price or options					$ 11.46				$ 11.46
Vesting period of stock options									2 years 2 months 12 days
Stock-based compensation expense									$ 6,500
Performance Award [Member] \| Stock Option And Performance Award [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense									$ 2,300

Stockholders' Equity And Stock-Based Compensation Expense (Common Stock Outstanding And Stockholders' Equity) (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Common Stock, Beginning balance	40,011,894	40,008,654	35,237,987	24,919,333	24,729,902	21,841,810	35,237,987	21,841,810
Common Stock, Proceeds from exercise of common stock warrants			554,019	588,235	189,431	2,888,092
Common Stock, Exercise of stock options	4,898	3,240	135,015	71,105
Common Stock, Proceeds from registered direct offering of common stock			4,081,633
Net loss
Common Stock, Ending balance	40,016,792	40,011,894	40,008,654	25,578,673	24,919,333	24,729,902	40,016,792	25,578,673
Stockholders' equity, Beginning balance	$ 276,480	$ 281,187	$ 92,200	$ 24,184	$ 24,832	$ 22,099	$ 92,200	$ 22,099
Stockholders' equity, Stock-based compensation for:							1,237	750
Stockholders' equity, Proceeds from exercise of common stock warrants			692	735	236	3,613
Stockholders' equity, Exercise of stock options	75	3	1,746	256
Stockholders' equity, Proceeds from registered direct offering of common stock			189,825				189,825
Net loss	(9,562)	(5,125)	(3,526)	(1,430)	(1,136)	(1,150)	(18,213)	(3,716)
Stockholders' equity, Ending balance	$ 267,565	$ 276,480	$ 281,187	$ 23,973	$ 24,184	$ 24,832	$ 267,565	$ 23,973
Stock Option [Member]
Common Stock, Stock-based compensation for:
Common Stock, Exercise of stock options	6,644			71,000			241,638	71,000
Stockholders' equity, Stock-based compensation for:	$ 24	$ 410	$ 249	$ 224	$ 249	$ 261
Non-Employee Stock Options [Member]
Common Stock, Stock-based compensation for:
Stockholders' equity, Stock-based compensation for:	$ 548	$ 5	$ 1	$ 4	$ 3	$ 9

Stockholders' Equity And Stock-Based Compensation Expense (Stock Options And Unvested Performance Award Outstanding Activity) (Details) - shares	3 Months Ended				9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercised	(4,898)	(3,240)	(135,015)	(71,105)
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding as of, Beginning			2,817,504		2,817,504
Options granted					92,500
Options exercised	(6,644)			(71,000)	(241,638)	(71,000)
Options forfeited/canceled					(12,139)
Outstanding as of, Ending	2,656,227				2,656,227
Performance Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding as of, Beginning			138,055		138,055
Options granted
Options exercised
Options forfeited/cancelled
Outstanding as of, Ending	138,055				138,055

Stockholders' Equity And Stock-Based Compensation Expense (Stock-Based Compensation Expenses) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 572	$ 228	$ 1,237	$ 750
Research and development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	452	109	867	335
General and administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 120	$ 119	$ 370	$ 415

Income Taxes (Narrative) (Details) - USD ($)	3 Months Ended	9 Months Ended
Income Taxes (Narrative) (Details) - USD ($)	Sep. 30, 2020	Sep. 30, 2020
Income Taxes [Abstract]
Provision for income taxes	$ 0	$ 0

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Commitments (Narrative) (Details) $ in Thousands	3 Months Ended		9 Months Ended
Commitments (Narrative) (Details) $ in Thousands	Sep. 30, 2021 USD ($) ft²	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) ft²	Sep. 30, 2020 USD ($)	Aug. 04, 2021 ft²
Operating Leased Assets [Line Items]
Cash paid for operating lease liabilities \| $	$ 41	$ 25	$ 68	$ 75
Non-cancellable commitments \| $	1,900		1,900
Building [Member]
Operating Leased Assets [Line Items]
Rent expense \| $	$ 41	$ 25	$ 98	$ 75
Austin, Texas [Member] \| Operating Leases [Member]
Operating Leased Assets [Line Items]
Office space \| ft²	6,000		6,000
Lease expiration date			Apr. 30, 2024
Austin, Texas [Member] \| Short-Term Operating Lease [Member]
Operating Leased Assets [Line Items]
Office space \| ft²	3,600		3,600
Lease expiration date			Apr. 30, 2022
Austin, Texas [Member] \| Building [Member]
Operating Leased Assets [Line Items]
Office space \| ft²					90,000

Commitments (Future Minimum Lease Payments) (Details) $ in Thousands	Sep. 30, 2021 USD ($)
Operating Leases [Member]
2021	$ 25
2022	102
2023	107
2024	36
Total future lease payments	270
Less: imputed interest	(11)
Total	259
Short-Term Operating Lease [Member]
2021	16
2022	21
2023
2024
Total future lease payments	37
Less: imputed interest
Total	$ 37

Sale Of Property And Equipment (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Sale Of Property And Equipment [Abstract]
Proceeds from sale of property and equipment				$ 360
Gross property and equipment	20,912	892	20,912	892	$ 97
Accumulated depreciation	$ 217	$ 878	$ 217	878	$ 86
Gain on sale of property and equipment				$ 346

2020 Cash Incentive Bonus Plan (Narrative) (Details) - Cash Incentive Bonus Plan [Member] - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Oct. 13, 2020
Cash Incentive Bonus Plan [Line Items]
Percentage of each cash bonus award associated with Valuation Milestone subject to adjustment and approval	58.00%
Cash bonus award		$ 7.3
Payments authorized or made to participants under the Plan	$ 0.0
Eighth Valuation Milestones [Member]
Cash Incentive Bonus Plan [Line Items]
Compensation expense	0.0
Minimum [Member]
Cash Incentive Bonus Plan [Line Items]
Valuation milestone amount in market capitalization	200.0
Minimum [Member] \| Exceeds $5 Billion Market Capitalization For No Less Than 20 Consecutive Trading Days [Member]
Cash Incentive Bonus Plan [Line Items]
Cash bonus award	139.1
Minimum [Member] \| Eighth Valuation Milestones [Member]
Cash Incentive Bonus Plan [Line Items]
Cash bonus award	93.7
Maximum [Member]
Cash Incentive Bonus Plan [Line Items]
Valuation milestone amount in market capitalization	5,000.0
Maximum [Member] \| Exceeds $5 Billion Market Capitalization For No Less Than 20 Consecutive Trading Days [Member]
Cash Incentive Bonus Plan [Line Items]
Cash bonus award	322.3
Maximum [Member] \| Eighth Valuation Milestones [Member]
Cash Incentive Bonus Plan [Line Items]
Cash bonus award	$ 225.0