0000950170-23-020579 | 10-Q | XBRL Viewer

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Balance Sheet Components - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accrued other liabilities	$ 1,134	$ 756
Accrued clinical trial liability	1,404	2,205
Total	$ 2,538	$ 2,961

Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Deficit Accumulated
Beginning balance (in shares) at Dec. 31, 2021		6,910,324
Beginning balance at Dec. 31, 2021	$ 36,117	$ 7	$ 136,173	$ (100,063)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock for cash, net of issuance cost (in shares)		262,770
Issuance of common stock for cash, net of issuance cost	1,403		1,403
Share-based compensation	328		328
Net loss	(8,491)			(8,491)
Ending balance (in shares) at Mar. 31, 2022		7,173,094
Ending balance at Mar. 31, 2022	29,357	$ 7	137,904	(108,554)
Beginning balance (in shares) at Dec. 31, 2022		10,518,539
Beginning balance at Dec. 31, 2022	18,111	$ 11	153,872	(135,772)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock for cash, net of issuance cost (in shares)		43,161
Issuance of common stock for cash, net of issuance cost	44		44
Share-based compensation	446		446
Net loss	(7,636)			(7,636)
Ending balance (in shares) at Mar. 31, 2023		10,561,700
Ending balance at Mar. 31, 2023	$ 10,965	$ 11	$ 154,362	$ (143,408)

- Definition

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

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- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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+ Details

Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2023

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Summary of Stock Options

The following shows the stock option activities for the three months ended March 31, 2023 and 2022:


	Total Options Outstanding			Weighted-Average Exercise Price
Balance—December 31, 2022		1,553,041		$	6.66
Granted		623,550			1.23
Exercised		—			—
Cancelled and forfeited		(29,180	)		3.59
Balance—March 31, 2023		2,147,411		$	5.13

Balance—December 31, 2021		790,637		$	32.82
Granted		303,125			5.26
Exercised		—			—
Cancelled and forfeited		(17,202	)		7.49
Balance—March 31, 2022		1,076,560			25.75

Summary of Information About Stock Options Outstanding

The following table summarizes information about stock options outstanding at March 31, 2023:


	Shares		Weighted Average Remaining Contractual Life (In Years)		Weighted Average Exercise Price		Aggregate Intrinsic Value
Options outstanding		2,147,411		8.73	$	5.13	$	676
Vested and expected to vest		2,147,411		8.73	$	5.13	$	676
Exercisable		558,724		7.47	$	8.39	$	28

Schedule of Stock Based Compensation Expense

The following table summarizes the components of stock-based compensation expense recognized in the Company’s Condensed Consolidated Statement of Operations for the three months ended March 31, 2023:


	Three Months Ended March 31,
	2023		2022
Research and development	$	146	$	102
General and administrative		300		226
Total	$	446	$	328

Share-based Payment Arrangement, Employee

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Summary of Grant Date Fair Value


	2023			2022
Expected term (in years)	6			6
Expected volatility		109	%		68	%
Risk-free interest rate		3.9	%	1.5% - 1.7%
Dividends		—	%		—	%

Net Loss Per Share (Tables)

3 Months Ended

Mar. 31, 2023

Earnings Per Share [Abstract]

Summary of Basis in Diluted Net Loss Per Share

The following table sets forth the computation of the Company’s basis in diluted net loss per share for the three months ended March 31, 2023 and 2022 (in thousands, except share and per share amounts):


	Three Months Ended March 31,
Numerator:	2023			2022
Net loss	$	(7,636	)	$	(8,491	)
Denominator:
Weighted-average common shares outstanding		13,763,173			7,167,255
Weighted-average shares used in computing basic and diluted net loss per share		13,763,173			7,167,255
Net loss per share attributable to common stockholders—basic and diluted	$	(0.55	)	$	(1.18	)

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share


	As of March 31,
	2023		2022
Options to purchase common stock		2,147,411		1,076,560
Common stock warrants		6,036		6,036
		2,153,447		1,082,596

Commitments and Contingencies - Future Minimum Rental Payments under Operating Leases with Noncancelable Terms (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Loss Contingencies [Line Items]
Less: current portion	$ (1,325)	$ (1,413)
Operating lease liabilities, less current portion	9,918	$ 10,330
Brisbane, California and Ann Arbor, Michigan
Loss Contingencies [Line Items]
2023 (excluding three months ended March 31, 2023)	1,912
2024	2,100
2025	1,861
2026	1,926
2027	1,994
2028 and beyond	6,410
Total minimum lease payments	16,203
Less: imputed interest	(4,960)
Present value of operating lease obligations	11,243
Less: current portion	(1,325)
Operating lease liabilities, less current portion	$ 9,918

Stock-Based Compensation - Summary of Stock Options (Details) - $ / shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Share-Based Payment Arrangement [Abstract]
Outstanding at beginning (in shares)	1,553,041	790,637
Granted (in shares)	623,550	303,125
Exercised (in shares)	0	0
Cancelled and forfeited (in shares)	(29,180)	(17,202)
Outstanding at end (in shares)	2,147,411	1,076,560
Outstanding at beginning (in dollars per share)	$ 6.66	$ 32.82
Granted (in dollars per share)	1.23	5.26
Exercised (in dollars per share)	0	0
Cancelled and forfeited (in dollars per share)	3.59	7.49
Outstanding at end (in dollars per share)	$ 5.13	$ 25.75

Stock-Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended
	Jan. 01, 2023	Jun. 17, 2022	Mar. 31, 2023	Mar. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, purchase price of common stock, percent			110.00%
Share-based compensation arrangement by share-based payment award, award vesting period			4 years
Share-based compensation arrangement by share-based payment award, expiration period			10 years
Granted (in shares)			623,550	303,125
Granted (in dollars per share)			$ 1.23	$ 5.26
Amended and Restated 2019 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, percentage of outstanding stock maximum		4.00%
Share-based compensation arrangement by share-based payment award, period of automatic increase to outstanding stock maximum		10 years
Share-based compensation arrangement by share-based payment award, shares issued in period	420,742
Common stock, capital shares reserved for future issuance			629,388
2019 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, percentage of outstanding stock maximum		1.50%
Share-based compensation arrangement by share-based payment award, shares issued in period	157,778		41,778
Common stock, capital shares reserved for future issuance			253,097
Share-based compensation arrangement by share-based payment award, maximum number of shares available for grant per year		500,000
Share-based Payment Arrangement, Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			623,550	303,125
Granted (in dollars per share)			$ 1.03	$ 4.37
Share-based payment arrangement, nonvested award, option, cost not yet recognized, amount			$ 4,140	$ 3,992
Share-based payment arrangement, nonvested award, cost not yet recognized, period for recognition			2 years 6 months	3 years 2 months 12 days

Balance Sheet Components - Schedule of Prepaid Expenses and Other Current Asset (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Prepaid expenses	$ 594	$ 703
Prepaid research and development costs	285	304
Other current assets	419	263
Total	$ 1,298	$ 1,270

Commitments and Contingencies - Narrative (Details) $ in Thousands		1 Months Ended	3 Months Ended
	Mar. 04, 2022 USD ($)	Jun. 30, 2022	Mar. 31, 2023 USD ($) Lease	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)	Jan. 31, 2022 USD ($) a	Feb. 28, 2019 a
Loss Contingencies [Line Items]
Operating lease right-of-use assets			$ 11,219		$ 11,650
Amount covered by insurance	$ 15,000
Accrued legal settlement			$ 450		450
Letter of Credit
Loss Contingencies [Line Items]
Borrowing capacity						$ 368
Ann Arbor, Michigan
Loss Contingencies [Line Items]
Term of contract			1 year 1 month 6 days
Number of non-cancelable lease agreements \| Lease			2
Brisbane, California
Loss Contingencies [Line Items]
Term of contract						8 years
Area of property (in sqft) \| a						20,116
South San Francisco, California
Loss Contingencies [Line Items]
Term of contract							5 years
Area of property (in sqft) \| a							9,780
Expiration date		Jan. 31, 2023	Feb. 29, 2024
Operating lease right-of-use assets			$ 11,219		11,650
Present value of operating lease obligations			11,243		$ 11,744
Rent expense			$ 710	$ 359

Stock-Based Compensation - Stock Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 446	$ 328
Research and Development Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	146	102
General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 300	$ 226

Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2023

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis

The following tables present the Company’s fair value hierarchy for assets measured at fair value on a recurring basis:


	As of March 31, 2023
	Level 1		Level 2		Level 3		Total
Cash and cash equivalents	$	22,925	$	—	$	—	$	22,925
Total	$	22,925	$	—	$	—	$	22,925

	As of December 31, 2022
	Level 1		Level 2		Level 3		Total
Cash and cash equivalents	$	31,230	$	—	$	—	$	31,230
Total	$	31,230	$	—	$	—	$	31,230

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 22,925	$ 31,230
Insurance recovery of legal settlement	450	450
Prepaid expenses and other current assets	1,298	1,270
Total current assets	24,673	32,950
Property and equipment-net	1,008	1,060
Operating lease right-of-use assets	11,219	11,650
Other noncurrent assets	429	429
Total assets	37,329	46,089
Current liabilities:
Accounts payable	1,157	1,108
Accrued legal settlement	450	450
Accrued expenses	2,538	2,961
Current loan payable (net of discount and issuance costs of $58 and nil, respectively)	1,481
Current operating lease liabilities	1,325	1,413
Accrued compensation	456	1,248
Interest payable	104	97
Total current liabilities	7,511	7,277
Loan payable (net of discount and issuance costs of $454 and $756, respectively)	8,935	10,371
Operating lease liabilities, less current portion	9,918	10,330
Total liabilities	26,364	27,978
Commitments and contingencies (Note 5)
Stockholders' equity:
Common stock, $0.001 par value; 100,000,000 shares authorized at March 31, 2022 and December 31, 2021; 7,173,094 and 6,910,324 shares issued and outstanding at March 31, 2022 and December 31, 2021, respectively	11	11
Additional paid-in capital	154,362	153,872
Accumulated deficit	(143,408)	(135,772)
Total stockholders’ equity	10,965	18,111
Total liabilities and stockholders’ equity	$ 37,329	$ 46,089

Balance Sheet Components - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Depreciation expense	$ 125	$ 108

Condensed Consolidated Statements of Stockholders' Equity (Parenthetical) $ in Thousands	3 Months Ended
	Mar. 31, 2022 USD ($)
Statement of Stockholders' Equity [Abstract]
Stock issuance costs	$ 44

Fair Value Measurements

3 Months Ended

Mar. 31, 2023

Fair Value Disclosures [Abstract]

Fair Value Measurements

3. FAIR VALUE MEASUREMENTS

The following tables present the Company’s fair value hierarchy for assets measured at fair value on a recurring basis:


	As of March 31, 2023
	Level 1		Level 2		Level 3		Total
Cash and cash equivalents	$	22,925	$	—	$	—	$	22,925
Total	$	22,925	$	—	$	—	$	22,925

	As of December 31, 2022
	Level 1		Level 2		Level 3		Total
Cash and cash equivalents	$	31,230	$	—	$	—	$	31,230
Total	$	31,230	$	—	$	—	$	31,230

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Retirement Plan - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Retirement Benefits [Abstract]
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 57	$ 24

Cover - shares	3 Months Ended
Cover - shares	Mar. 31, 2023	May 04, 2023
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2023
Document Transition Report	false
Entity File Number	001-35890
Entity Registrant Name	Tempest Therapeutics, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	45-1472564
Entity Address, Address Line One	2000 Sierra Point Parkway
Entity Address, Address Line Two	Suite 400
Entity Address, City or Town	Brisbane
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94005
City Area Code	(415)
Local Phone Number	798-8589
Title of 12(b) Security	Common Stock, $0.001 par value
Trading Symbol	TPST
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		11,586,406
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2023
Current Fiscal Year End Date	--12-31
Amendment Flag	false
Entity Central Index Key	0001544227
Security Exchange Name	NASDAQ

Retirement Plan

3 Months Ended

Mar. 31, 2023

Retirement Benefits [Abstract]

Retirement Plan

9. RETIREMENT PLAN

The Company participates in a qualified 401(k) Plan sponsored by its professional service organization. The retirement plan is a defined contribution plan covering eligible employees. Participants may contribute a portion of their annual compensation limited to a maximum annual amount set by the Internal Revenue Service. During the three months ended March 31, 2023 and 2022, the Company contributed $57 and $24 to the 401(k) Plan, respectively.

- Definition

The entire disclosure for retirement benefits.

+ References

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+ Details

Net Loss Per Share

3 Months Ended

Mar. 31, 2023

Earnings Per Share [Abstract]

Net Loss Per Share

10. NET LOSS PER SHARE


	Three Months Ended March 31,
Numerator:	2023			2022
Net loss	$	(7,636	)	$	(8,491	)
Denominator:
Weighted-average common shares outstanding		13,763,173			7,167,255
Weighted-average shares used in computing basic and diluted net loss per share		13,763,173			7,167,255
Net loss per share attributable to common stockholders—basic and diluted	$	(0.55	)	$	(1.18	)

As of March 31, 2023 and 2022, the Company’s potentially dilutive securities included unvested stock warrants and stock options, which have been excluded from the computation of diluted net loss per share attributable to common stockholders as the effect would be anti-dilutive. The issuance of pre-funded warrants have been included in the computation of basic and diluted net loss per share attributable to common stockholders. Based on the amounts outstanding as of March 31, 2023 and

2022, the Company excluded the following potential common shares from the computation of diluted net loss per share attributable to common stockholders because including them would have had an anti-dilutive effect:


	As of March 31,
	2023		2022
Options to purchase common stock		2,147,411		1,076,560
Common stock warrants		6,036		6,036
		2,153,447		1,082,596

Condensed Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Net of discount and issuance costs, Current	$ 58
Net of discount and issuance costs	$ 351	$ 454
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	10,561,700	10,518,539
Common stock, shares outstanding	10,561,700	10,518,539

Commitment and Contingencies

3 Months Ended

Mar. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

Commitment and Contingencies

5. COMMITMENTS AND CONTINGENCIES

Facilities Lease Agreements—In February 2019, the Company entered into a 5-year office lease agreement for a 9,780 square feet facility in South San Francisco, California. The original lease term expires on February 29, 2024. In June 2022, the lease was amended to terminate early on January 31, 2023. The amendment was not accounted for as a separate contract and the lease liability and the right-of-use asset were remeasured on the lease modification date.

On March 29, 2021, TempestTx, Inc. (“Private Tempest”) entered into an Agreement and Plan of Merger (the “Merger Agreement”) with Millendo Therapeutics, Inc. (“Millendo”). On June 25, 2021, Private Tempest completed the merger with Millendo and as a result of the merger, the Company assumed Millendo’s noncancelable operating leases for office space which have remaining lease terms of approximately 1.1 years. In February 2019 and October 2018, Millendo entered into two noncancellable operating leases for office space in Ann Arbor, Michigan (“Ann Arbor Leases”), one that Millendo took possession of in April 2019 and the other that Millendo took possession of in July 2019, respectively. The Ann Arbor Leases expire in June 2024 and March 2024.

In January 2022, the Company entered into a new 8-year office lease agreement for a 20,116 square feet facility in Brisbane, California ("Brisbane Lease"). The lease commenced in December 2022.

As of March 31, 2023 and December 31, 2022, the balance of the operating lease right of use assets were $11,219 and $11,650, respectively, and the related operating lease liability were $11,243 and $11,744, respectively, as shown in the accompanying consolidated balance sheets.

Rent expense was $710 and $359 for the three months ended March 31, 2023 and 2022, respectively.

As of March 31, 2023, future minimum lease payments under the Brisbane Lease and Ann Arbor Leases were as follows:



Year Ending	Total Commitment
2023 (excluding three months ended March 31, 2023)	$	1,912
2024		2,100
2025		1,861
2026		1,926
2027		1,994
2028 and beyond		6,410
Total minimum lease payments		16,203
Less: imputed interest		(4,960	)
Present value of operating lease obligations		11,243
Less: current portion		(1,325	)
Noncurrent operating lease obligations	$	9,918

Related to this Brisbane Lease agreement, the Company entered into a letter of credit with a bank to deposit $368 in a separate account that is classified as restricted cash to serve as security rent deposit. This amount is included in other noncurrent assets in the accompanying Consolidated Balance Sheets as of March 31, 2023.

Guarantees and Indemnifications—In the normal course of business, the Company enters into agreements that contain a variety of representations and provide for general indemnification. The Company’s exposure under these agreements is unknown because it involves claims that may be made against the Company in the future. To date, the Company has not paid any claims or been required to defend any action related to its indemnification obligations. As of March 31, 2023 and 2022, the Company does not have any material indemnification claims that were probable or reasonably possible and consequently has not recorded related liabilities.

Legal Proceedings—Liabilities for loss contingencies arising from claims, assessments, litigation, fines, penalties, and other sources are recorded when it is probable that a liability has been incurred and the amount can be reasonably estimated. As a result of the merger with Millendo, the Company is party to various litigation matters given Millendo’s role as successor to OvaScience, Inc. (“OvaScience”). OvaScience merged with Millendo in 2018. Prior to the merger with Millendo, OvaScience was sued in three matters that are disclosed below.

On November 9, 2016, a purported shareholder derivative action was filed in Massachusetts State court (Cima v. Dipp) against OvaScience and certain former officers and directors of OvaScience and OvaScience alleging breach of fiduciary duties, unjust enrichment, abuse of control, gross mismanagement and waste of corporate assets for purported actions related to OvaScience’s January 2015 follow-on public offering. As of September 12, 2022, the parties have reached an agreement in principle and have executed a term sheet in connection with a settlement. On September 13, 2022, the parties filed a joint motion to stay the case pending settlement. On September 15, 2022, the court issued a 90-day nisi order. On December 14, 2022, the court extended that order for 60 days to February 20, 2023. On February 17, 2023, the court extended the order until March 22, 2023 and set a court appearance for March 23, 2023. On March 23, 2023, the court granted preliminary approval of the settlement and set a final fairness hearing for June 12, 2023. Any final settlement is subject to Court approval.

On March 24, 2017, a purported shareholder class action lawsuit was filed in Massachusetts Federal court (Dahhan v. OvaScience, Inc.) against OvaScience and certain former officers of OvaScience alleging violations of Sections 10(b) and 20(a) of the Exchange Act (the “Dahhan Action”). On March 4, 2022, the parties filed a motion to preliminarily approve a settlement of the action. The settlement amount of $15 million was funded entirely by insurance. All defendants expressly deny liability. On April 1, 2022, the Court preliminarily approved the settlement. On December 20, 2022, the Court entered final approval of the settlement and dismissed the Dahhan Action with prejudice. The settlement included a release of all claims against the defendants thus no liability related to this matter was recorded in our Condensed Consolidated Balance Sheets as of March 31, 2023 and December 31, 2022, respectively.

On July 27, 2017, a purported shareholder derivative complaint was filed in Massachusetts Federal court (Chiu v. Dipp) against OvaScience and certain former officers and directors of OvaScience alleging breach of fiduciary duties, unjust enrichment and violations of Section 14(a) of the Exchange Act. related to OvaScience’s January 2015 follow-on public offering and other public statements concerning OvaScience’s AUGMENT treatment. Following the Court’s dismissal of an amended complaint, the parties agreed that plaintiffs could file a second amended complaint and that the case would be stayed pending the resolution of the Dahhan Action. In May 2018, the court entered an order staying this case pending the resolution of the Dahhan Action. As of September 12, 2022, the parties have reached an agreement in principle and have executed a term sheet in connection with the settlement. On February 14, 2023, the parties informed the court that, subject to court approval, they had reached an agreement to settle Chiu v. Dipp as well as Cima v. Dipp. The parties requested a 90-day stay in order to present the settlement to the state court in Cima v. Dipp first. On February 16, 2023, the Court granted the 90-day stay. On May 2, 2023 the Court extended the stay through July 12, 2023. Upon final approval of the Cima settlement, the Company expects that a motion to dismiss Chiu v. Dipp will also be filed.

Stock-Based Compensation

3 Months Ended

Mar. 31, 2023

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation

8. STOCK-BASED COMPENSATION

Equity Plans

In 2011, Private Tempest adopted the 2011 Equity Incentive Plan (the “2011 Plan), and in 2017, Private Tempest adopted the 2017 Equity Incentive Plan (the “2017 Plan”), and together with the 2011 Plan, the “Tempest Prior Plans.” The Tempest Prior Plans have been terminated and no additional grants may be made under either plan. All stock awards granted under the Tempest Prior Plans will remain subject to the terms of the applicable prior plan. As a result of the merger with Millendo, the Tempest Prior Plans were assumed by the Company.

The Board of Millendo adopted the 2019 Equity Incentive Plan (the “2019 Plan”) on April 29, 2019, subject to approval by the Company’s stockholders, and became effective with such stockholder approval on June 11, 2019. On June 17, 2022, the Company’s stockholders approved the Amended and Restated 2019 Equity Incentive Plan (the “A&R 2019 Plan”), which amended and restated the 2019 Plan and will be a successor to, and replacement of, the 2019 Plan. The number of shares of the Company's common stock reserved for issuance under the A&R 2019 Plan will automatically increase on January 1st of each year, for a period of 10 years, from January 1, 2020 continuing through January 1, 2029, by 4% of the total number of shares of the Company's common stock outstanding on December 31 of the preceding calendar year, or a lesser number of shares as may be determined by the Board of Directors. On January 1, 2023, the common stock reserved for issuance was increased by 420,742 shares. As of March 31, 2023, a total of 629,388 shares are available for future grant under the A&R 2019 Plan.

The A&R 2019 Plan allows the Company to grant stock awards to employees, directors and consultants of the Company, including incentive stock options (“ISOs”), nonqualified stock options (“NSOs”), stock appreciation rights, restricted stock awards, restricted stock unit awards and other stock awards.

The Company measures employee and non-employee stock-based awards at grant date fair value and records compensation expense on a straight-line basis over the vesting period of the award.

Employee Stock Ownership Plan

The Board of Millendo adopted the 2019 Employee Stock Purchase Plan on April 29, 2019, which became effective upon stockholder approval on June 11, 2019. On June 17, 2022, the Company’s stockholders approved the Amended and Restated 2019 Employee Stock Purchase Plan (the “2019 ESPP”). The 2019 ESPP enables employees to purchase shares of the Company's common stock through offerings of rights to purchase the Company's common stock to all eligible employees.

The 2019 ESPP provides that the number of shares of common stock reserved for issuance under the 2019 ESPP will automatically increase on January 1, 2023 and continuing through (and including) January 1, 2029, by the lesser of 1.5% of the total number of shares of Common Stock outstanding on December 31st of the preceding calendar year, (ii) 500,000 shares of Common Stock, or (iii) such lesser number of shares of Common Stock as determined by the Board of Directors (which may be zero). On January 1, 2023, the common stock reserved for issuance was increased by 157,778 shares.

As of March 31, 2023, 253,097 shares of common stock remained available for future issuance under the 2019 ESPP. During the three months ended March 31, 2023, 41,778 shares of common stock had been issued under the 2019 ESPP.

Stock Options

Options to purchase the Company’s common stock may be granted at a price not less than the fair market value in the case of both NSOs and ISOs, except for an options holder who owns more than 10% of the voting power of all classes of stock of the Company, in which case the exercise price shall be no less than 110% of the fair market value per share on the grant date. Stock options granted under the Plans generally vest over four years and expire no later than ten (10) years from the date of grant. Vested options can be exercised at any time.

Prior to the merger with Millendo, the grant date fair market value of the shares of common stock underlying stock options has historically been determined by the Company’s Board of Directors. Up until the merger, there had been no public market for the Company’s common stock, and therefore the Board of Directors exercised reasonable judgment and considered a number of objective and subjective factors to determine the best estimate of the fair market value, which included valuations performed by an independent third-party, important developments in the Company’s operations, sales of convertible preferred stock, actual operating results, financial performance, the conditions in the life sciences industry, the economy in general, the stock price performance and volatility of comparable public companies, and the lack of liquidity of the Company’s common stock.

The following shows the stock option activities for the three months ended March 31, 2023 and 2022:


	Total Options Outstanding			Weighted-Average Exercise Price
Balance—December 31, 2022		1,553,041		$	6.66
Granted		623,550			1.23
Exercised		—			—
Cancelled and forfeited		(29,180	)		3.59
Balance—March 31, 2023		2,147,411		$	5.13

Balance—December 31, 2021		790,637		$	32.82
Granted		303,125			5.26
Exercised		—			—
Cancelled and forfeited		(17,202	)		7.49
Balance—March 31, 2022		1,076,560			25.75

The following table summarizes information about stock options outstanding at March 31, 2023:


	Shares		Weighted Average Remaining Contractual Life (In Years)		Weighted Average Exercise Price		Aggregate Intrinsic Value
Options outstanding		2,147,411		8.73	$	5.13	$	676
Vested and expected to vest		2,147,411		8.73	$	5.13	$	676
Exercisable		558,724		7.47	$	8.39	$	28

During the three months ended March 31, 2023 and 2022, the Company granted employees and non-employees stock options to purchase 623,550 and 303,125 shares of common stock with a weighted-average grant date fair value of $1.03 and $4.37 per share, respectively. As of March 31, 2023 and 2022, total unrecognized compensation costs related to unvested employee stock options were $4,140 and $3,992, respectively. These costs are expected to be recognized over a weighted-average period of approximately 2.5 years and 3.2 years, respectively.

The Company estimated the fair value of stock options using the Black-Scholes option pricing valuation model. The fair value of employee stock options is being amortized on the straight-line basis over the requisite service period of the awards. The fair value of employee stock options was estimated using the following assumptions for the three months ended March 31, 2023 and 2022:


	2023			2022
Expected term (in years)	6			6
Expected volatility		109	%		68	%
Risk-free interest rate		3.9	%	1.5% - 1.7%
Dividends		—	%		—	%

Expected Term—The expected term of options granted represents the period of time that the options are expected to be outstanding. Due to the lack of historical exercise history, the expected term of the Company’s employee stock options has been determined utilizing the simplified method for awards that qualify as plain-vanilla options.

Expected Volatility—The expected stock price volatility assumption was determined by examining the historical volatilities for industry peers, as the Company did not have any trading history for the Company’s common stock. The Company will continue to analyze the historical stock price volatility and expected term assumption as more historical data for the Company’s common stock becomes available.

Risk-Free Interest Rate—The risk-free interest rate assumption is based on the U.S. Treasury instruments whose term was consistent with the expected term of the Company’s stock options.

Dividends—The Company has not paid any cash dividends on common stock since inception and does not anticipate paying any dividends in the foreseeable future. Consequently, an expected dividend yield of zero was used.

Stock-Based Compensation Expense


	Three Months Ended March 31,
	2023		2022
Research and development	$	146	$	102
General and administrative		300		226
Total	$	446	$	328

Stock-Based Compensation - Grant Date Fair Value of Option (Details) - Share-based Payment Arrangement, Employee	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	6 years	6 years
Expected volatility	109.00%	68.00%
Risk-free interest rate	3.90%
Dividends	0.00%	0.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate		1.50%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate		1.70%

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Operating activities:
Net loss	$ (7,636)	$ (8,491)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	125	108
Stock-based compensation expense	446	328
Non-cash lease expense	432	311
Non-cash interest and other expense, net	53	64
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(28)	178
Accounts payable	12	(323)
Accrued expenses and other liabilities	(1,214)	1,063
Interest payable	7	2
Operating lease liabilities	(500)	(347)
Cash used in operating activities	(8,303)	(7,107)
Investing activities:
Purchase of property and equipment	(46)	(3)
Cash used in investing activities	(46)	(3)
Financing activities:
Proceeds from the issuance of common stock, net of issuance costs	44	1,403
Cash provided by financing activities	44	1,403
Net decrease in cash and cash equivalents	(8,305)	(5,707)
Cash, cash equivalents and restricted cash at beginning of period	31,598	51,829
Cash, cash equivalents and restricted cash at end of period	23,293	46,122
Supplemental disclosure of cash flow information:
Cash paid for interest	292	268
Cash paid for income taxes	$ 24
Non-cash investing activities:
Property and equipment in accounts payable		$ 16

Net Loss Per Share - Antidilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings	2,153,447	1,082,596
Options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings	2,147,411	1,076,560
Common stock warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings	6,036	6,036

Stockholders' Equity

3 Months Ended

Mar. 31, 2023

Temporary Equity Disclosure [Abstract]

Stockholders' Equity

7. STOCKHOLDERS' EQUITY

Common Stock

As of March 31, 2023 and December 31, 2022, the Company was authorized to issue 100,000,000 shares of common stock and 5,000,000 shares of preferred stock, each with a par value of $0.001 per share. Of the common stock shares authorized, 10,561,700 and 10,518,539 were issued and outstanding at March 31, 2023 and December 31, 2022, respectively. There were no shares subject to repurchase due to remaining vesting requirements. Common stockholders are entitled to dividends as declared by the Board of Directors, subject to rights of holders of all classes of stock outstanding having priority rights as to dividends. There was no preferred stock issued nor outstanding as of March 31, 2023 and December 31, 2022.

Common stockholders are entitled to dividends as declared by the Board of Directors, subject to rights of holders of all classes of stock outstanding having priority rights as to dividends. There have been no dividends declared to date. The holders of each share of common stock are entitled to one vote. Except for effecting or validating certain specific actions intended to protect the preferred stockholders, the holders of common stock vote together with preferred stockholders and have the right to elect one member of the Company’s Board of Directors.

ATM Program

On July 23, 2021, the Company entered into a sales agreement with Jefferies LLC, pursuant to which the Company may sell, from time to time, up to an aggregate sales price of $100,000,000 of its common stock through Jefferies LLC (the "ATM Program"). Our ability to sell securities under the ATM program will be limited until we are no longer subject to the SEC’s “baby shelf” limitations.

Pre-Funded Warrants

In April 2022, the Company completed a PIPE financing, which included the issuance of pre-funded warrants to purchase up to 3,206,020 shares of its common stock at a price per pre-funded warrant of $2.359 to the PIPE Investors. The pre-funded warrants provide that the holder will not have the right to exercise any portion of its warrants if such holder, together with its affiliates, would beneficially own in excess of 9.99% of the number of shares of the Company’s common stock outstanding immediately after giving effect to such exercise (the “Beneficial Ownership Limitation”); provided, however, that the holder may increase or decrease the Beneficial Ownership Limitation by giving 61 days’ notice to the Company, but not to any percentage in excess of 19.99%.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

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+ Details

Balance Sheet Components - Summary of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Property and equipment	$ 2,495	$ 2,421
Less accumulated depreciation	(1,487)	(1,361)
Property and equipment-net	1,008	1,060
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property and equipment	168	168
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment	328	310
Lab equipment
Property, Plant and Equipment [Line Items]
Property and equipment	1,077	1,061
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment	$ 922	$ 882

Net Loss Per Share - Summary of Basis in Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Numerator:
Net loss	$ (7,636)	$ (8,491)
Denominator:
Weighted-average common shares outstanding (in shares)	13,763,173	7,167,255
Weighted-average shares of common stock outstanding, diluted (in shares)	13,763,173	7,167,255
Weighted-average shares of common stock outstanding, basic (in shares)	13,763,173	7,167,255
Net loss per share of common stock, basic (in dollars per share)	$ (0.55)	$ (1.18)
Net loss per share of common stock, diluted (in dollars per share)	$ (0.55)	$ (1.18)

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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- Definition

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

+ References

+ Details

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Operating expenses:
Research and development	$ 4,678	$ 5,109
General and administrative	2,903	3,052
Loss from operations	(7,581)	(8,161)
Other income (expense), net:
Interest expense	(344)	(333)
Interest income and other income (expense), net	289	3
Total other income (expense), net	(55)	(330)
Provision for income taxes	0	0
Net loss	$ (7,636)	$ (8,491)
Net loss per share of common stock and pre-funded warrants, basic	$ (0.55)	$ (1.18)
Net loss per share of common stock and pre-funded warrants, diluted	$ (0.55)	$ (1.18)
Weighted-average shares of common stock and pre-funded warrants outstanding, basic	13,763,173	7,167,255
Weighted-average shares of common stock and pre-funded warrants outstanding, diluted	13,763,173	7,167,255

Organization and Description of the Business - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	Apr. 29, 2022	Mar. 31, 2023	Dec. 31, 2022
Class of Stock [Line Items]
Cash and cash equivalents		$ 22,925	$ 31,230
PIPE Financing
Class of Stock [Line Items]
Consideration received	$ 14,500
Shares issued in transaction	3,149,912
Stock price (in dollars per share)	$ 2.36
Number of warrants issued	3,206,020
PIPE Financing \| EcoR1 Capital, LLC and Versant Venture Capital
Class of Stock [Line Items]
Pre-funded warrant price (in dollars per share)	2.359

Balance Sheet Components

3 Months Ended

Mar. 31, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Balance Sheet Components

4. BALANCE SHEET COMPONENTS

Prepaid expenses and other current assets consist of the following:


	March 31, 2023		December 31, 2022
Prepaid expenses	$	594	$	703
Prepaid research and development costs		285		304
Other current assets		419		263
Total	$	1,298	$	1,270

Property and equipment, net, consists of the following:


	March 31, 2023			December 31, 2022
Computer equipment and software	$	168		$	168
Furniture and fixtures		328			310
Lab equipment		1,077			1,061
Leasehold improvements		922			882
Property and equipment		2,495			2,421
Less accumulated depreciation		(1,487	)		(1,361	)
Property and equipment—net	$	1,008		$	1,060

Depreciation expense for the three months ended March 31, 2023 and 2022 were $125 and $108, respectively.

Accrued liabilities consist of the following:


	March 31, 2023		December 31, 2022
Accrued other liabilities	$	1,134	$	756
Accrued clinical trial liability		1,404		2,205
Total	$	2,538	$	2,961

Balance Sheet Components (Tables)

3 Months Ended

Mar. 31, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Prepaid Expenses and Other Current Asset

Prepaid expenses and other current assets consist of the following:


	March 31, 2023		December 31, 2022
Prepaid expenses	$	594	$	703
Prepaid research and development costs		285		304
Other current assets		419		263
Total	$	1,298	$	1,270

Summary of Property and Equipment, Net

Property and equipment, net, consists of the following:


	March 31, 2023			December 31, 2022
Computer equipment and software	$	168		$	168
Furniture and fixtures		328			310
Lab equipment		1,077			1,061
Leasehold improvements		922			882
Property and equipment		2,495			2,421
Less accumulated depreciation		(1,487	)		(1,361	)
Property and equipment—net	$	1,008		$	1,060

Schedule of Accrued Liabilities

Accrued liabilities consist of the following:


	March 31, 2023		December 31, 2022
Accrued other liabilities	$	1,134	$	756
Accrued clinical trial liability		1,404		2,205
Total	$	2,538	$	2,961

Loan Payable

3 Months Ended

Mar. 31, 2023

Debt Disclosure [Abstract]

Loan Payable

6. LOAN PAYABLE

On January 15, 2021, the Company entered into a loan agreement with Oxford Finance LLC (the "Lender") to borrow a term loan amount of $35,000 to be funded in three tranches. Tranche A of $15,000 was wired to the Company on January 15, 2021. Tranche B of $10,000 expired on March 31, 2022. Tranche C of $10,000 is available at the Lender’s option.

On December 23, 2022, the Company entered into a First Amendment to the loan agreement. The amendment modified the agreement as follows: (i) each of the Company and Millendo Therapeutics US, Inc., a Delaware corporation and wholly owned subsidiary of the Company (“Millendo”), were joined as co-borrowers under the Loan Agreement; (ii) the interest-only repayment period was extended through December 31, 2023 (which interest-only period may be further extended through June 30, 2024 under certain circumstances); and (iii) a security interest in all of the assets of the Company, TempestTx and Millendo, including any intellectual property, was granted to the Lender. In addition, the Lender permitted a one-time prepayment in the amount of $5.0 million, which the Company paid on December 23, 2022.

Following the amendment to the loan agreement, the term loan matures on August 1, 2025 and has an annual floating interest rate of 7.15% which is an Index Rate plus 7.10%. Index Rate is the greater of (i) 1-Month CME Term SOFR or (ii) 0.05%. Monthly principal payments of $513 will begin on January 1, 2024. Related to this borrowing, the Company recorded loan discounts totaling $898 and paid $95 of debt issuance costs. These amounts would be amortized as additional interest expense over the life of the loan. As of March 31, 2023, the balance of the loan payable (net of debt issuance costs) was $10.4 million. The carrying value of the loan approximates fair value (Level 2).

For the three months ended March 31, 2023 and 2022, total interest expense was $344 and $333, respectively.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-URI https://asc.fasb.org/topic&trid=2208564

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (h)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (g)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1E
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (i)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

+ Details

Stockholders' Equity - Narrative (Details)			3 Months Ended
Stockholders' Equity - Narrative (Details)	Apr. 29, 2022 $ / shares shares	Jul. 23, 2021 USD ($)	Mar. 31, 2023 $ / shares shares	Mar. 31, 2022 shares	Dec. 31, 2022 $ / shares shares
Temporary Equity [Line Items]
Common stock, shares authorized			100,000,000		100,000,000
Preferred stock, shares authorized			5,000,000		5,000,000
Common stock, par value (in dollars per share) \| $ / shares			$ 0.001		$ 0.001
Common stock, shares issued			10,561,700		10,518,539
Common stock, shares outstanding			10,561,700		10,518,539
Preferred stock, shares outstanding			0		0
Common Stock
Temporary Equity [Line Items]
Issuance of common stock for cash (in shares)			43,161	262,770
PIPE Financing
Temporary Equity [Line Items]
Number of warrants issued	3,206,020
Beneficial ownership percentage	9.99%
Warrant notice period	61 days
Beneficial ownership percentage after issuing notice	19.99%
Jefferies LLC \| At-The-Market Program
Temporary Equity [Line Items]
Sale of Stock, Amount Authorized \| $		$ 100,000,000
EcoR1 Capital, LLC and Versant Venture Capital \| PIPE Financing
Temporary Equity [Line Items]
Pre-funded warrant price (in dollars per share) \| $ / shares	2.359

Organization and Description of the Business

3 Months Ended

Mar. 31, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization and Description of the Business

1. ORGANIZATION AND DESCRIPTION OF THE BUSINESS

Description of Business

Tempest Therapeutics, Inc. (“Tempest” or the “Company”) is a clinical-stage oncology company advancing small molecules that combine both tumor-targeted and immune-mediated mechanisms with the potential to treat a wide range of tumors. The Company’s two novel clinical programs are TPST-1120 and TPST-1495, antagonists of PPARα and EP2/EP4, respectively. Both programs are advancing through clinical trials designed to study the agents as monotherapies and in combination with other approved agents. Tempest is also developing an orally available inhibitor of TREX-1, a target that controls activation of the cGAS/STING pathway. Tempest is headquartered in Brisbane, California.

Liquidity and Management Plans

The accompanying financial statements have been prepared assuming the Company will continue as a going concern. The Company has incurred operating losses since inception. As of March 31, 2023, we had cash and cash equivalents of $22.9 million. The Company has not yet generated product sales and as a result has experienced operating losses since inception. The Company expects to incur additional losses in the future to conduct research and development and will need to raise additional capital to continue operations. We intend to raise the needed capital through the issuance of additional debt or equity, including in connection with potential merger opportunities, or through business development activities. Our ability to continue as a going concern is dependent upon our ability to successfully accomplish these plans and secure sources of financing and ultimately attain profitable operations. If we are unable to obtain adequate capital, we could be forced to cease operations. Management believes that its existing cash and cash equivalents will be sufficient to fund the Company’s cash requirements for at least 12 months following the issuance of these financial statements.

On April 29, 2022, the Company completed a private investment in public equity (“PIPE”) financing from the sale of 3,149,912 shares of its common stock at a price per share of $2.36 and, and in lieu of shares of common stock, pre-funded warrants to purchase up to 3,206,020 shares of its common stock at a price per pre-funded warrant of $2.359 to EcoR1 Capital, LLC and Versant Venture Capital (the “PIPE Investors”). Net proceeds from the PIPE financings totaled approximately $14.5 million, after deducting offering expenses. The Company entered into a registration rights agreement (the “Registration Rights Agreement”) with the PIPE Investors pursuant to which the Company filed a registration statement with the SEC registering the resale of the 3,149,912 shares common stock and the 3,206,020 shares of common stock underlying the pre-funded warrants issued in the PIPE financing.

Loan Payable - Narrative (Details) $ in Thousands			3 Months Ended
Loan Payable - Narrative (Details) $ in Thousands	Dec. 23, 2022 USD ($)	Jan. 15, 2021 USD ($) Tranche	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Long-term debt			$ 10,400
Loan payable (net of discount and issuance costs of $489 and $756, respectively)			$ 8,935		$ 10,371
Term Loan
Debt Instrument [Line Items]
Loan amount		$ 35,000
Loan mature date	Aug. 01, 2025
Number of tranches \| Tranche		3
Debt instrument interest term			the interest-only repayment period was extended through December 31, 2023 (which interest-only period may be further extended through June 30, 2024 under certain circumstances)
Prepayment amount	$ 5,000
Annual floating interest rate	7.15%
Debt instrument, basis spread on variable rate	7.10%
Thershold index rate	0.05%
Monthly principal payments	$ 513
Loan discounts	898
Payments of debt issuance costs	$ 95
Interest expense			$ 344	$ 333
Tranche A Term Loan
Debt Instrument [Line Items]
Loan amount		$ 15,000
Tranche B Term Loan
Debt Instrument [Line Items]
Loan amount		$ 10,000
Loan mature date		Mar. 31, 2022
Tranche C Term Loan
Debt Instrument [Line Items]
Loan amount		$ 10,000

Commitment and Contingencies (Tables)

3 Months Ended

Mar. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

Future minimum rental payments under operating leases with noncancelable terms

As of March 31, 2023, future minimum lease payments under the Brisbane Lease and Ann Arbor Leases were as follows:



Year Ending	Total Commitment
2023 (excluding three months ended March 31, 2023)	$	1,912
2024		2,100
2025		1,861
2026		1,926
2027		1,994
2028 and beyond		6,410
Total minimum lease payments		16,203
Less: imputed interest		(4,960	)
Present value of operating lease obligations		11,243
Less: current portion		(1,325	)
Noncurrent operating lease obligations	$	9,918

Summary of Significant Accounting Policies

3 Months Ended

Mar. 31, 2023

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Significant Accounting Policies -- The Company’s significant accounting policies are described in Note 2, “Summary of Significant Accounting Policies,” in the Company’s Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission (“SEC”) on March 22, 2023. There have been no material changes to the significant accounting policies during the period ended March 31, 2023.

Basis of Presentation—The unaudited interim Condensed Consolidated Financial Statements have been prepared pursuant to the rules and regulations of the U.S. Securities and Exchange Commission. Accordingly, certain information and footnote disclosures normally included in annual financial statements prepared in accordance with GAAP have been omitted. These unaudited interim Condensed Consolidated Financial Statements should be read in conjunction with the Company’s audited consolidated financial statements and notes included in the company’s Annual Report on Form 10-K for the year ended December 31, 2022.

The Company has prepared the accompanying Condensed Consolidated Financial Statements on the same basis as the audited financial statements, and the unaudited interim financial statements include, in the Company’s opinion, all adjustments, consisting only of normal recurring adjustments that the Company considers necessary for a fair presentation of its financial position and results of operations for these periods.

Use of Estimates—The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. On an ongoing basis, the Company evaluates its estimates and assumptions, including those related to research and development accruals, recoverability of long-lived assets, right-of-use assets, lease obligations, stock-based compensation and income taxes uncertainties and valuation allowances. Management bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from those estimates.

Summary of Significant Accounting Policies (Policies)	3 Months Ended
Summary of Significant Accounting Policies (Policies)	Mar. 31, 2023
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation—The unaudited interim Condensed Consolidated Financial Statements have been prepared pursuant to the rules and regulations of the U.S. Securities and Exchange Commission. Accordingly, certain information and footnote disclosures normally included in annual financial statements prepared in accordance with GAAP have been omitted. These unaudited interim Condensed Consolidated Financial Statements should be read in conjunction with the Company’s audited consolidated financial statements and notes included in the company’s Annual Report on Form 10-K for the year ended December 31, 2022.
Unaudited Interim Financial Statement	The Company has prepared the accompanying Condensed Consolidated Financial Statements on the same basis as the audited financial statements, and the unaudited interim financial statements include, in the Company’s opinion, all adjustments, consisting only of normal recurring adjustments that the Company considers necessary for a fair presentation of its financial position and results of operations for these periods.
Use of Estimates	Use of Estimates—The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. On an ongoing basis, the Company evaluates its estimates and assumptions, including those related to research and development accruals, recoverability of long-lived assets, right-of-use assets, lease obligations, stock-based compensation and income taxes uncertainties and valuation allowances. Management bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from those estimates.

Stock-Based Compensation - Summary of Information About Stock Options Outstanding (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Share-Based Payment Arrangement [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	2,147,411	1,553,041	1,076,560	790,637
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	8 years 8 months 23 days
Outstanding (in dollars per share)	$ 5.13	$ 6.66	$ 25.75	$ 32.82
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 676
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	2,147,411
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Remaining Contractual Term	8 years 8 months 23 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price	$ 5.13
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value	$ 676
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	558,724
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term	7 years 5 months 19 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 8.39
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 28

Fair Value Measurements - Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	$ 22,925	$ 31,230
Total	22,925	31,230
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	22,925	31,230
Total	22,925	31,230
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Total	0	0
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Total	$ 0	$ 0