0000950170-23-040556 | 10-Q | XBRL Viewer

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Stockholder's Equity - Additional Information (Detail) $ / shares in Units, $ in Thousands	1 Months Ended	6 Months Ended
	Jun. 30, 2023 USD ($) $ / shares shares	Jun. 30, 2023 USD ($) $ / shares
Class of Stock [Line Items]
Common stock, shares issued \| shares	5,660,871
Common stock, issued price per share	$ 11.5	$ 11.5
Proceeds from issuance of common stock and pre-funded warrants, net of offering costs \| $	$ 93,600	$ 93,577
Pre-funded Warrants
Class of Stock [Line Items]
Warrants issued \| shares	3,034,782
Warrants issued price per warrants	$ 11.4999	$ 11.4999
Warrants exercisable exercise price	0.0001	0.0001
Overallotment Option
Class of Stock [Line Items]
Common stock, issued price per share	$ 11.5	$ 11.5
Option to purchase additional shares of common stock \| shares	1,304,347

Share-Based Compensation

6 Months Ended

Jun. 30, 2023

Share-Based Payment Arrangement [Abstract]

Share-Based Compensation

Equity Incentive Plan

In May 2023, our stockholders approved an amendment to our Amended and Restated 2014 Equity Incentive Plan, or 2014 Plan, to, among other things, increase the number of shares available for future grant by 4,050,000 shares and remove the automatic annual 4% increase to the number of shares available for future grant.

Performance-Based Restricted Stock Units

On May 31, 2023, upon approval by our stockholders of our amended 2014 Plan, we granted an aggregate of 1,313,100 performance-based restricted stock units, or PSUs, to certain executives. The PSUs vest in six equal tranches upon the achievement of certain milestones and service conditions.

Share-Based Compensation Expense

The following table summarizes share-based compensation expense for all share-based compensation arrangements, in thousands:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2023		2022		2023		2022
Research and development	$	3,134	$	2,597	$	6,207	$	5,053
General and administrative		3,853		3,911		7,618		8,105
Total share-based compensation expense	$	6,987	$	6,508	$	13,825	$	13,158

As of June 30, 2023, unrecognized estimated compensation expense related to stock options and restricted stock units was approximately $45.4 million and $12.6 million, respectively, which is expected to be recognized over a weighted average period of approximately 2.6 years for both stock options and restricted stock units. As of June 30, 2023, we determined that the vesting of the PSUs was not probable and therefore have not included them in share-based compensation expense or unrecognized estimated compensation expense.

Organization and Basis of Presentation	6 Months Ended
Jun. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	1. Organization and Basis of Presentation The Company Kura Oncology, Inc. is a clinical-stage biopharmaceutical company committed to realizing the promise of precision medicines for the treatment of cancer. Our pipeline consists of small molecule product candidates that target cancer signaling pathways where there is a strong scientific and clinical rationale to improve outcomes, and we intend to pair them with molecular or cellular diagnostics to identify those patients most likely to respond to treatment. We plan to advance our product candidates through a combination of internal development and strategic partnerships while maintaining significant development and commercial rights. References in these Notes to Unaudited Condensed Financial Statements to the “Company,” “we,” “our” or “us,” refer to Kura Oncology, Inc. Basis of Presentation The accompanying unaudited condensed financial statements should be read in conjunction with the audited financial statements and notes thereto in our Annual Report on Form 10-K for the fiscal year ended December 31, 2022, as filed with the Securities and Exchange Commission on February 23, 2023, from which we derived our balance sheet as of December 31, 2022. The accompanying unaudited condensed financial statements have been prepared in accordance with U.S. generally accepted accounting principles, or GAAP, for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, since they are interim statements, the accompanying unaudited condensed financial statements do not include all of the information and notes required by GAAP for complete financial statements. The accompanying unaudited condensed financial statements reflect all adjustments, consisting of normal recurring adjustments, that are, in the opinion of our management, necessary to a fair statement of the results for the interim periods presented. Interim results are not necessarily indicative of results for a full year. The preparation of the unaudited condensed financial statements in accordance with GAAP requires our management to make estimates and assumptions that affect the amounts reported on our unaudited condensed financial statements and accompanying notes. The amounts reported could differ under different estimates and assumptions. On an ongoing basis, we evaluate our estimates and judgments, which are based on historical and anticipated results and trends and on various other assumptions that management believes to be reasonable under the circumstances. By their nature, estimates are subject to an inherent degree of uncertainty and, as such, actual results may differ from management’s estimates.

Organization and Basis of Presentation

6 Months Ended

Jun. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization and Basis of Presentation

1. Organization and Basis of Presentation

The Company

Kura Oncology, Inc. is a clinical-stage biopharmaceutical company committed to realizing the promise of precision medicines for the treatment of cancer. Our pipeline consists of small molecule product candidates that target cancer signaling pathways where there is a strong scientific and clinical rationale to improve outcomes, and we intend to pair them with molecular or cellular diagnostics to identify those patients most likely to respond to treatment. We plan to advance our product candidates through a combination of internal development and strategic partnerships while maintaining significant development and commercial rights.

References in these Notes to Unaudited Condensed Financial Statements to the “Company,” “we,” “our” or “us,” refer to Kura Oncology, Inc.

Basis of Presentation

The accompanying unaudited condensed financial statements should be read in conjunction with the audited financial statements and notes thereto in our Annual Report on Form 10-K for the fiscal year ended December 31, 2022, as filed with the Securities and Exchange Commission on February 23, 2023, from which we derived our balance sheet as of December 31, 2022. The accompanying unaudited condensed financial statements have been prepared in accordance with U.S. generally accepted accounting principles, or GAAP, for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, since they are interim statements, the accompanying unaudited condensed financial statements do not include all of the information and notes required by GAAP for complete financial statements. The accompanying unaudited condensed financial statements reflect all adjustments, consisting of normal recurring adjustments, that are, in the opinion of our management, necessary to a fair statement of the results for the interim periods presented. Interim results are not necessarily indicative of results for a full year.

The preparation of the unaudited condensed financial statements in accordance with GAAP requires our management to make estimates and assumptions that affect the amounts reported on our unaudited condensed financial statements and accompanying notes. The amounts reported could differ under different estimates and assumptions. On an ongoing basis, we evaluate our estimates and judgments, which are based on historical and anticipated results and trends and on various other assumptions that management believes to be reasonable under the circumstances. By their nature, estimates are subject to an inherent degree of uncertainty and, as such, actual results may differ from management’s estimates.

Share-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions		6 Months Ended	12 Months Ended
	May 31, 2023	Jun. 30, 2023	Dec. 31, 2022
Amended and Restated 2014 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of automatic increase in common shares reserved for future issuance pursuant to future grants			4.00%
Additional shares available for future grant	4,050,000
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized estimated stock option compensation expenses		$ 45.4
Weighted average service period		2 years 7 months 6 days
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized estimated restricted stock units compensation expenses		$ 12.6
Weighted average service period		2 years 7 months 6 days
Performance Based Restricted Stock Units \| Amended and Restated 2014 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
PSUs Granted	1,313,100

Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2023

Accounting Policies [Abstract]

Schedule of Reconciliation of Cash, Cash Equivalents and Restricted Cash

The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the unaudited condensed balance sheets that sum to the total of the amounts shown in the unaudited condensed statements of cash flows, in thousands:


	June 30, 2023		December 31, 2022		June 30, 2022		December 31, 2021
Cash and cash equivalents	$	49,124	$	51,802	$	39,257	$	90,672
Restricted cash		210		210		210		210
Total	$	49,334	$	52,012	$	39,467	$	90,882

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	Dec. 31, 2021
Summary Of Significant Accounting Policies [Line Items]
Restricted cash pledged as collateral	$ 210	$ 210	$ 210	$ 210
Employee retention credit recognized during period	2,800
Employee retention credit receivable during period	$ 2,800
Total potentially dilutive securities	13,743,000	9,101,000
Collateral Pledged
Summary Of Significant Accounting Policies [Line Items]
Restricted cash pledged as collateral	$ 200

Balance Sheet Detail

6 Months Ended

Jun. 30, 2023

Balance Sheet Related Disclosures [Abstract]

Balance Sheet Detail

5. Balance Sheet Detail

Property and equipment consisted of the following, in thousands:


	June 30, 2023			December 31, 2022
Laboratory and computer equipment	$	1,637		$	1,568
Leasehold improvements		1,543			1,543
Furniture and fixtures		1,095			1,032
Property and equipment, gross		4,275			4,143
Less: accumulated depreciation		(2,022	)		(1,603	)
Property and equipment, net	$	2,253		$	2,540

Accounts payable and accrued expenses consisted of the following, in thousands:


	June 30, 2023		December 31, 2022
Accounts payable	$	2,337	$	1,533
Accrued clinical trial research and development expenses		3,857		2,440
Accrued other research and development expenses		6,781		5,030
Accrued compensation and benefits		6,840		10,300
Other accrued expenses		1,739		2,436
Total accounts payable and accrued expenses	$	21,554	$	21,739

Fair Value Measurements

6 Months Ended

Jun. 30, 2023

Fair Value Disclosures [Abstract]

Fair Value Measurements

4. Fair Value Measurements

As of June 30, 2023 and December 31, 2022, we had cash equivalents and short-term investments measured at fair value on a recurring basis.

Available-for-sale securities consist of U.S. Treasury securities, which are measured at fair value using Level 1 inputs, and corporate debt securities, commercial paper, U.S. Agency bonds and non-U.S. government and supranational debt securities which are measured at fair value using Level 2 inputs. We determine the fair value of Level 2 related securities with the aid of valuations provided by third parties using proprietary valuation models and analytical tools. These valuation models and analytical tools use market pricing or prices for similar instruments that are both objective and publicly available, including matrix pricing or reported trades, benchmark yields, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids and/or offers. We validate the fair values of Level 2 financial instruments by comparing these fair values to a third-party pricing source.

The following tables summarize, by major security type, our cash equivalents and short-term investments that are measured at fair value on a recurring basis and are categorized using the fair value hierarchy, in thousands:


	June 30, 2023
	Total		Level 1		Level 2
Cash equivalents:
Money market funds	$	38,460	$	38,460	$	—

Short-term investments:
U.S. Treasury securities		242,230		242,230		—
Corporate debt securities		90,214	—			90,214
Commercial paper		55,735	—			55,735
U.S. Agency bonds		22,062	—			22,062
Non-U.S. government and supranational debt securities		17,614		—		17,614
Total short-term investments		427,855		242,230		185,625
Total	$	466,315	$	280,690	$	185,625


	December 31, 2022
	Total		Level 1		Level 2
Cash equivalents:
Money market funds	$	37,878	$	37,878	$	—
U.S. Agency bonds		9,956		—		9,956
Total cash equivalents		47,834		37,878		9,956

Short-term investments:
U.S. Treasury securities		180,049		180,049		—
Corporate debt securities		111,832	—			111,832
Commercial paper		52,941	—			52,941
U.S. Agency bonds		16,043	—			16,043
Non-U.S. government and supranational debt securities		25,318		—		25,318
Total short-term investments		386,183		180,049		206,134
Total	$	434,017	$	217,927	$	216,090

We believe that our term loan facility bears interest at a rate that approximates prevailing market rates for instruments with similar characteristics and, accordingly, the carrying value of the term loan facility approximates fair value. The fair value of our term loan facility is determined using Level 2 inputs in the fair value hierarchy.

Leases - Additional Information (Detail) - USD ($)	1 Months Ended		3 Months Ended		6 Months Ended
Leases - Additional Information (Detail) - USD ($)	May 31, 2020	Mar. 31, 2020	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	May 31, 2022
Lessee Lease Description [Line Items]
Lessee, operating lease, expiration period					We currently have three operating leases for administrative and research and development office and lab space in San Diego, California and Boston, Massachusetts that expire between July 2024 and November 2025.
Lease option to extend, description					Two of our leases include renewal options for an additional five years, which were not included in the determination of the right-of-use, or ROU, asset or lease liability as the renewal was not reasonably certain at the inception of the lease
Weighted-average discount rate			5.50%		5.50%		5.50%
Weighted-average remaining lease term			1 year 10 months 24 days		1 year 10 months 24 days		2 years 3 months 18 days
Total cash paid for amounts included in the measurement of lease liabilities			$ 600,000	$ 600,000	$ 1,200,000	$ 1,200,000
ROU assets obtained in exchange for operating lease liabilities					0	0
ASC 842
Lessee Lease Description [Line Items]
Total operating lease rent expense			500,000	$ 500,000	1,000,000	$ 1,000,000
San Diego Corporate Headquarters Lease
Lessee Lease Description [Line Items]
Operating lease, existence of option to extend		true
Lease agreement additional extended lease term	5 years
Tenant improvement allowance	$ 1,000,000
San Diego Lease for Lab and Office Space
Lessee Lease Description [Line Items]
Tenant improvement allowance								$ 100,000
Office Lease in Boston \| Letter of Credit
Lessee Lease Description [Line Items]
Letter of Credit			$ 200,000		$ 200,000
Boston Lease
Lessee Lease Description [Line Items]
Operating lease, existence of option to extend	true
Lease agreement additional extended lease term		5 years

Summary of Significant Accounting Policies

6 Months Ended

Jun. 30, 2023

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Restricted Cash

Under the terms of an office lease entered into in March 2020, we are required to maintain a standby letter of credit during the term of the lease. As of June 30, 2023, restricted cash of $0.2 million was pledged as collateral for the letter of credit.


	June 30, 2023		December 31, 2022		June 30, 2022		December 31, 2021
Cash and cash equivalents	$	49,124	$	51,802	$	39,257	$	90,672
Restricted cash		210		210		210		210
Total	$	49,334	$	52,012	$	39,467	$	90,882

Allowance for Credit Losses

For available-for-sale securities in an unrealized loss position, we first assess whether we intend to sell, or if it is more likely than not that we will be required to sell, the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value through earnings. For available-for-sale securities that do not meet the aforementioned criteria, we evaluate whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, we consider the severity of the impairment, any changes in interest rates, market conditions, changes to the underlying credit ratings and forecasted recovery, among other factors. The credit-related portion of unrealized losses, and any subsequent improvements, are recorded in interest income through an allowance account. Any impairment that has not been recorded through an allowance for credit losses is included in other comprehensive income (loss) on the unaudited condensed statements of operations and comprehensive loss.

We elected the practical expedient to exclude the applicable accrued interest from both the fair value and amortized costs basis of our available-for-sale securities for purposes of identifying and measuring an impairment. Accrued interest receivable on available-for-sale securities is recorded within prepaid expenses and other current assets on our unaudited condensed balance sheets. Our accounting policy is to not measure an allowance for credit loss for accrued interest receivable and to write-off any uncollectible accrued interest receivable as a reversal of interest income in a timely manner, which we consider to be in the period in which we determine the accrued interest will not be collected by us.

Concentration of Credit Risk

Financial instruments that potentially subject us to significant concentrations of credit risk consist primarily of cash, cash equivalents and short-term investments. We maintain deposits in federally insured financial institutions in excess of federally insured limits. We have established guidelines to limit our exposure to credit risk by placing investments with high credit quality financial institutions, diversifying our investment portfolio and placing investments with maturities that maintain safety and liquidity. We periodically review and modify these guidelines to maximize trends in yields and interest rates without compromising safety and liquidity.

Employee Retention Credit

Under the Coronavirus Aid, Relief, and Economic Security Act of 2020, or CARES Act, we were eligible to claim the employee retention credit, which is a refundable tax credit against certain employment taxes. For the six months ended June 30, 2023, we recognized $2.8 million of employee retention credits related to wages paid to our employees from July 2020 through September 2021 within operating expenses as a reduction to personnel costs in the unaudited condensed statements of operations and comprehensive loss. We filed for the credit with the Internal Revenue Service in the first quarter of 2023. As of June 30, 2023, an employee retention credit receivable of $2.8 million was included within prepaid expenses and other current assets in the unaudited condensed balance sheets and we expect to receive such credit in the form of a cash payment during the second half of 2023.

Net Loss per Share

Basic net loss per common share is calculated by dividing the net loss by the weighted-average number of common shares outstanding for the period, which includes the shares related to outstanding pre-funded warrants (see Note 7), but excludes other potential common stock equivalents. Pre-funded warrants are considered outstanding for the purposes of computing basic and diluted net loss per share because shares may be issued for little or no additional consideration, and are fully vested and exercisable. Diluted net loss per share is calculated by dividing net loss by the weighted-average number of common shares and common stock equivalents outstanding for the period. As we have reported net loss for the three and six months ended June 30, 2023 and 2022, dilutive net loss per common share is the same as basic net loss per common share for those periods. Common stock equivalents outstanding are comprised of stock options, restricted stock units, performance-based restricted stock units, warrants and employee stock purchase plan rights and are only included in the calculation of diluted earnings per common share when net income is reported and their effect is dilutive. Common stock equivalents outstanding at June 30, 2023 and 2022 totaling approximately 13,743,000 and 9,101,000, respectively, were excluded from the computation of dilutive weighted-average shares outstanding because their effect would be anti-dilutive.

Recent Accounting Pronouncements

From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board or other standard setting bodies that we adopt as of the specified effective date. We have evaluated recently issued accounting pronouncements and, based on our preliminary assessment, we do not believe any will have a material impact on our unaudited condensed financial statements or related footnote disclosures.

Condensed Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Operating Activities
Net loss	$ (71,243)	$ (67,222)
Adjustments to reconcile net loss to net cash used in operating activities:
Share-based compensation expense	13,825	13,158
Amortization of premium and accretion of discounts on marketable securities, net	(3,797)	1,894
Depreciation expense	419	360
Non-cash interest expense	236
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(226)	(5,199)
Operating lease right-of-use and other long-term assets	502	(5)
Accounts payable and accrued expenses	(1,251)	(5,592)
Other long-term liabilities	46	84
Net cash used in operating activities	(61,489)	(62,522)
Investing Activities
Purchases of marketable securities	(213,464)	(107,579)
Maturities of marketable securities	178,399	115,947
Purchases of property and equipment	(132)	(233)
Net cash (used in) provided by investing activities	(35,197)	8,135
Financing Activities
Proceeds from issuance of common stock and pre-funded warrants, net of offering costs	93,577
Proceeds from issuance of stock under equity plans	431	2,972
Net cash provided by financing activities	94,008	2,972
Net decrease in cash, cash equivalents and restricted cash	(2,678)	(51,415)
Cash, cash equivalents and restricted cash at beginning of period	52,012	90,882
Cash, cash equivalents and restricted cash at end of period	$ 49,334	$ 39,467

Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2023

Fair Value Disclosures [Abstract]

Schedule Of Fair Value Measurements, By Major Security Type


	June 30, 2023
	Total		Level 1		Level 2
Cash equivalents:
Money market funds	$	38,460	$	38,460	$	—

Short-term investments:
U.S. Treasury securities		242,230		242,230		—
Corporate debt securities		90,214	—			90,214
Commercial paper		55,735	—			55,735
U.S. Agency bonds		22,062	—			22,062
Non-U.S. government and supranational debt securities		17,614		—		17,614
Total short-term investments		427,855		242,230		185,625
Total	$	466,315	$	280,690	$	185,625


	December 31, 2022
	Total		Level 1		Level 2
Cash equivalents:
Money market funds	$	37,878	$	37,878	$	—
U.S. Agency bonds		9,956		—		9,956
Total cash equivalents		47,834		37,878		9,956

Short-term investments:
U.S. Treasury securities		180,049		180,049		—
Corporate debt securities		111,832	—			111,832
Commercial paper		52,941	—			52,941
U.S. Agency bonds		16,043	—			16,043
Non-U.S. government and supranational debt securities		25,318		—		25,318
Total short-term investments		386,183		180,049		206,134
Total	$	434,017	$	217,927	$	216,090

Summary of Significant Accounting Policies - Schedule of Reconciliation of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Dec. 31, 2021
Accounting Policies [Abstract]
Cash and cash equivalents	$ 49,124	$ 51,802	$ 39,257	$ 90,672
Restricted cash	210	210	210	210
Total	$ 49,334	$ 52,012	$ 39,467	$ 90,882

Leases

6 Months Ended

Jun. 30, 2023

Leases [Abstract]

Leases

6. Leases

We currently have three operating leases for administrative and research and development office and lab space in San Diego, California and Boston, Massachusetts that expire between July 2024 and November 2025. Under the terms of the operating leases, we are required to pay our proportionate share of property taxes, insurance and normal maintenance costs. Two of our leases include renewal options for an additional five years, which were not included in the determination of the right-of-use, or ROU, asset or lease liability as the renewal was not reasonably certain at the inception of the lease. Our San Diego corporate headquarters lease and our San Diego lease for lab and office space provided for $1.0 million and $0.1 million, respectively, in reimbursements for allowable tenant improvements, which effectively reduced the total lease payments owed. Under the terms of our office lease in Boston, we are required to maintain a standby letter of credit of approximately $0.2 million during the term of the lease.

Maturities of lease liabilities as of June 30, 2023 are as follows, in thousands:


Year Ending December 31,
2023 (remaining)	$	1,196
2024		1,863
2025		929
Total lease payments		3,988
Less: imputed interest		(188	)
Total operating lease liabilities	$	3,800

As of June 30, 2023 and December 31, 2022, the weighted-average discount rate was 5.5% for both periods, and the weighted-average remaining lease term was 1.9 years and 2.3 years, respectively. Total cash paid for amounts included in the measurement of operating lease liabilities was $0.6 million for both the three months ended June 30, 2023 and 2022. Total cash paid for amounts included in the measurement of operating lease liabilities was $1.2 million for both the six months ended June 30, 2023 and 2022. There were no operating lease ROU assets obtained in exchange for operating lease liabilities for the six months ended June 30, 2023 and 2022. Total operating lease expense for the three months ended June 30, 2023 and 2022 was approximately $0.5 million in both periods. Total operating lease expense for the six months ended June 30, 2023 and 2022 was approximately $1.0 million in both periods.

Condensed Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Operating Expenses:
Research and development	$ 28,182	$ 24,258	$ 53,374	$ 45,171
General and administrative	11,821	11,075	23,195	22,944
Total operating expenses	40,003	35,333	76,569	68,115
Other Income (Expense):
Interest and other income, net	3,216	564	6,077	893
Interest expense	(387)		(751)
Total other income, net	2,829	564	5,326	893
Net Loss	$ (37,174)	$ (34,769)	$ (71,243)	$ (67,222)
Net loss per share, basic	$ (0.53)	$ (0.52)	$ (1.03)	$ (1.01)
Net loss per share, diluted	$ (0.53)	$ (0.52)	$ (1.03)	$ (1.01)
Weighted average number of shares used in computing net loss per share, basic	69,795	66,672	69,103	66,639
Weighted average number of shares used in computing net loss per share, diluted	69,795	66,672	69,103	66,639
Comprehensive Loss:
Net loss	$ (37,174)	$ (34,769)	$ (71,243)	$ (67,222)
Other comprehensive income (loss):
Unrealized gain (loss) on marketable securities and foreign currency	674	(1,167)	2,810	(6,026)
Comprehensive Loss	$ (36,500)	$ (35,936)	$ (68,433)	$ (73,248)

Investments - Investments Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Schedule Of Available For Sale Securities [Line Items]
Short-term investments, Fair Value	$ 427,855	$ 386,183
Fair Value Measurements on Recurring Basis
Schedule Of Available For Sale Securities [Line Items]
Cash equivalents, Amortized Cost		47,834
Cash equivalents, Fair Value		47,834
Short-term investments, Amortized Cost	433,077	394,215
Short-term investments, Unrealized Gains	22	27
Short-term investments, Unrealized Losses	(5,244)	(8,059)
Short-term investments, Fair Value	427,855	386,183
Cash equivalents and Short-term investments, Amortized Cost	471,537	442,049
Cash equivalents and Short-term investments, Unrealized Gains	22	27
Cash equivalents and Short-term investments, Unrealized Losses	(5,244)	(8,059)
Cash equivalents and Short-term investments, Estimated Fair Value	466,315	434,017
Fair Value Measurements on Recurring Basis \| Money Market Funds
Schedule Of Available For Sale Securities [Line Items]
Cash equivalents, Amortized Cost	38,460	37,878
Cash equivalents, Fair Value	$ 38,460	$ 37,878
Fair Value Measurements on Recurring Basis \| Money Market Funds \| Maximum
Schedule Of Available For Sale Securities [Line Items]
Maturities (years)	1 year	1 year
Fair Value Measurements on Recurring Basis \| U.S. Treasury Securities
Schedule Of Available For Sale Securities [Line Items]
Short-term investments, Amortized Cost	$ 244,260	$ 183,051
Short-term investments, Unrealized Gains	5	16
Short-term investments, Unrealized Losses	(2,035)	(3,018)
Short-term investments, Fair Value	$ 242,230	$ 180,049
Fair Value Measurements on Recurring Basis \| U.S. Treasury Securities \| Maximum
Schedule Of Available For Sale Securities [Line Items]
Maturities (years)	2 years	2 years
Fair Value Measurements on Recurring Basis \| Corporate Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Short-term investments, Amortized Cost	$ 92,723	$ 115,763
Short-term investments, Unrealized Losses	(2,509)	(3,931)
Short-term investments, Fair Value	$ 90,214	$ 111,832
Fair Value Measurements on Recurring Basis \| Corporate Debt Securities \| Maximum
Schedule Of Available For Sale Securities [Line Items]
Maturities (years)	2 years	2 years
Fair Value Measurements on Recurring Basis \| Commercial Paper
Schedule Of Available For Sale Securities [Line Items]
Short-term investments, Amortized Cost	$ 55,780	$ 52,941
Short-term investments, Unrealized Losses	(45)
Short-term investments, Fair Value	$ 55,735	$ 52,941
Fair Value Measurements on Recurring Basis \| Commercial Paper \| Maximum
Schedule Of Available For Sale Securities [Line Items]
Maturities (years)	1 year	1 year
Fair Value Measurements on Recurring Basis \| U.S. Agency Bonds
Schedule Of Available For Sale Securities [Line Items]
Cash equivalents, Amortized Cost		$ 9,956
Cash equivalents, Fair Value		9,956
Short-term investments, Amortized Cost	$ 22,060	16,192
Short-term investments, Unrealized Gains	17	11
Short-term investments, Unrealized Losses	(15)	(160)
Short-term investments, Fair Value	$ 22,062	$ 16,043
Fair Value Measurements on Recurring Basis \| U.S. Agency Bonds \| Maximum
Schedule Of Available For Sale Securities [Line Items]
Maturities (years)		1 year
Maturities (years)	1 year	1 year
Fair Value Measurements on Recurring Basis \| Non U S Government And Supranational Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Short-term investments, Amortized Cost	$ 18,254	$ 26,268
Short-term investments, Unrealized Losses	(640)	(950)
Short-term investments, Fair Value	$ 17,614	$ 25,318
Fair Value Measurements on Recurring Basis \| Non U S Government And Supranational Debt Securities \| Maximum
Schedule Of Available For Sale Securities [Line Items]
Maturities (years)	1 year	2 years

Leases - Schedule of Maturities of Lease Liabilities (Detail) $ in Thousands	Jun. 30, 2023 USD ($)
Leases [Abstract]
2023 (remaining)	$ 1,196
2024	1,863
2025	929
Total lease payments	3,988
Less: imputed interest	(188)
Total operating lease liabilities	$ 3,800

Balance Sheet Detail - Summary of Property and Equipment (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 4,275	$ 4,143
Less: accumulated depreciation	(2,022)	(1,603)
Property and equipment, net	2,253	2,540
Laboratory and Computer Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,637	1,568
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,543	1,543
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 1,095	$ 1,032

Condensed Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 49,124	$ 51,802
Short-term investments	427,855	386,183
Prepaid expenses and other current assets	8,667	8,441
Total current assets	485,646	446,426
Property and equipment, net	2,253	2,540
Restricted cash	210	210
Operating lease right-of-use assets	2,933	3,842
Other long-term assets	3,695	3,288
Total assets	494,737	456,306
Current liabilities:
Accounts payable and accrued expenses	21,554	21,739
Current operating lease liabilities	2,345	2,318
Total current liabilities	23,899	24,057
Long-term debt, net	9,244	9,158
Long-term operating lease liabilities	1,455	2,548
Other long-term liabilities	461	265
Total liabilities	35,059	36,028
Stockholders'equity:
Preferred stock, $0.0001 par value; 10,000 shares authorized; no shares issued and outstanding
Common stock, $0.0001 par value; 200,000 shares authorized; 74,143 and 68,314 shares issued and outstanding as of June 30, 2023 and December 31, 2022, respectively	7	7
Additional paid-in capital	1,104,944	997,111
Accumulated other comprehensive loss	(5,222)	(8,032)
Accumulated deficit	(640,051)	(568,808)
Total stockholders'equity	459,678	420,278
Total liabilities and stockholders'equity	$ 494,737	$ 456,306

Stockholders' Equity

6 Months Ended

Jun. 30, 2023

Equity [Abstract]

Stockholders' Equity

7. Stockholders’ Equity

In June 2023, we completed a public offering in which we sold an aggregate of 5,660,871 shares of our common stock at a price of $11.50 per share and pre-funded warrants to purchase 3,034,782 shares of our common stock at a price of $11.4999 per pre-funded warrant. The exercise price of each pre-funded warrant is $0.0001 per share and the pre-funded warrants are exercisable from the date of issuance until fully exercised. Net proceeds from the public offering, after deducting underwriting discounts and commissions and offering expenses, were approximately $93.6 million. In addition, the underwriters were granted a 30-day option to purchase up to 1,304,347 additional shares of our common stock, or the Overallotment Option, at the $11.50 per share public offering price. The common stock, pre-funded warrants, and Overallotment Option met the accounting standards guidance for equity classification. As of June 30, 2023 the Overallotment Option was unexercised and it subsequently expired without being exercised in July 2023. We measured the fair value of the Overallotment Option using the Black-Scholes valuation model, which represents a Level 3 fair value measurement, and determined that the value was not material.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481004/946-505-50-6

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480237/815-40-50-6

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-16

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

+ Details

Leases (Tables)

6 Months Ended

Jun. 30, 2023

Leases [Abstract]

Schedule of Maturities of Lease Liabilities

Maturities of lease liabilities as of June 30, 2023 are as follows, in thousands:


Year Ending December 31,
2023 (remaining)	$	1,196
2024		1,863
2025		929
Total lease payments		3,988
Less: imputed interest		(188	)
Total operating lease liabilities	$	3,800

Balance Sheet Detail - Summary of Current Accrued Expenses (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Accrued Liabilities, Current [Abstract]
Accounts payable	$ 2,337	$ 1,533
Accrued clinical trial research and development expenses	3,857	2,440
Accrued other research and development expenses	6,781	5,030
Accrued compensation and benefits	6,840	10,300
Other accrued expenses	1,739	2,436
Total accounts payable and accrued expenses	$ 21,554	$ 21,739

Summary of Significant Accounting Policies (Policies)

6 Months Ended

Jun. 30, 2023

Accounting Policies [Abstract]

Restricted Cash


	June 30, 2023		December 31, 2022		June 30, 2022		December 31, 2021
Cash and cash equivalents	$	49,124	$	51,802	$	39,257	$	90,672
Restricted cash		210		210		210		210
Total	$	49,334	$	52,012	$	39,467	$	90,882

Allowance for Credit Losses on Available-for-Sale Debt Securities

Allowance for Credit Losses

Concentration of Credit Risk

Net Loss per Share

Recent Accounting Pronouncements

Investments

6 Months Ended

Jun. 30, 2023

Investments, All Other Investments [Abstract]

Investments

3. Investments

We invest in available-for-sale securities consisting of money market funds, U.S. Treasury securities, corporate debt securities, commercial paper, U.S. Agency bonds and non-U.S. government and supranational debt securities. Available-for-sale securities are classified as either cash and cash equivalents or short-term investments on our unaudited condensed balance sheets.

The following tables summarize, by major security type, our short-term investments that are measured at fair value on a recurring basis, in thousands:


		June 30, 2023
	Maturities (years)	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Cash equivalents:
Money market funds	1 or less	$	38,460	$	—	$	—		$	38,460

Short-term investments:
U.S. Treasury securities	2 or less		244,260		5		(2,035	)		242,230
Corporate debt securities	2 or less		92,723		—		(2,509	)		90,214
Commercial paper	1 or less		55,780		—		(45	)		55,735
U.S. Agency bonds	1 or less		22,060		17		(15	)		22,062
Non-U.S. government and supranational debt securities	1 or less		18,254		—		(640	)		17,614
Total short-term investments			433,077		22		(5,244	)		427,855
Total		$	471,537	$	22	$	(5,244	)	$	466,315


		December 31, 2022
	Maturities (years)	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Cash equivalents:
Money market funds	1 or less	$	37,878	$	—	$	—		$	37,878
U.S. Agency bonds	1 or less		9,956		—		—			9,956
Total cash equivalents			47,834		—		—			47,834

Short-term investments:
U.S. Treasury securities	2 or less		183,051		16		(3,018	)		180,049
Corporate debt securities	2 or less		115,763		—		(3,931	)		111,832
Commercial paper	1 or less		52,941		—		—			52,941
U.S. Agency bonds	1 or less		16,192		11		(160	)		16,043
Non-U.S. government and supranational debt securities	2 or less		26,268		—		(950	)		25,318
Total short-term investments			394,215		27		(8,059	)		386,183
Total		$	442,049	$	27	$	(8,059	)	$	434,017

Short-term investments are classified as current assets, even though the stated maturity date may be one year or more beyond the current balance sheet date, which reflects management’s intention to use the proceeds from sales of these securities to fund our operations, as necessary. As of June 30, 2023 and December 31, 2022, short-term investments of $368.5 million and $274.3 million, respectively, had maturities less than one year, and short-term investments of $59.4 million and $111.9 million, respectively, had maturities between one to two years. We had no realized gains or losses for the six months ended June 30, 2023 and 2022.

As of June 30, 2023, 52 available-for-sale securities with a fair market value of $387.4 million were in gross unrealized loss positions, $144.0 million of which were in a continuous unrealized loss position for greater than 12 months. We do not intend to sell these available-for-sale securities, and it is not more likely than not that we will be required to sell these securities prior to recovery of their amortized cost basis. Based on our review of these available-for-sale securities, the unrealized losses at June 30, 2023 were primarily due to changes in interest rates and not due to increased credit risks associated with specific securities. We have no allowance for credit losses as of June 30, 2023 and December 31, 2022. Unrealized gains and losses that are not credit-related are included in accumulated other comprehensive loss.

Accrued interest receivable on available-for-sale securities was $0.9 million as of June 30, 2023 and December 31, 2022. We have not written off any accrued interest receivables for the six months ended June 30, 2023 and 2022.

Share-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2023

Share-Based Payment Arrangement [Abstract]

Summary of Share-based Compensation Expense

The following table summarizes share-based compensation expense for all share-based compensation arrangements, in thousands:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2023		2022		2023		2022
Research and development	$	3,134	$	2,597	$	6,207	$	5,053
General and administrative		3,853		3,911		7,618		8,105
Total share-based compensation expense	$	6,987	$	6,508	$	13,825	$	13,158

Balance Sheet Detail (Tables)

6 Months Ended

Jun. 30, 2023

Balance Sheet Related Disclosures [Abstract]

Summary of Property and Equipment

Property and equipment consisted of the following, in thousands:


	June 30, 2023			December 31, 2022
Laboratory and computer equipment	$	1,637		$	1,568
Leasehold improvements		1,543			1,543
Furniture and fixtures		1,095			1,032
Property and equipment, gross		4,275			4,143
Less: accumulated depreciation		(2,022	)		(1,603	)
Property and equipment, net	$	2,253		$	2,540

Summary of Accounts Payable and Accrued Expenses

Accounts payable and accrued expenses consisted of the following, in thousands:


	June 30, 2023		December 31, 2022
Accounts payable	$	2,337	$	1,533
Accrued clinical trial research and development expenses		3,857		2,440
Accrued other research and development expenses		6,781		5,030
Accrued compensation and benefits		6,840		10,300
Other accrued expenses		1,739		2,436
Total accounts payable and accrued expenses	$	21,554	$	21,739

Fair Value Measurements - Schedule Of Fair Value Measurements, By Major Security Type (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	$ 427,855	$ 386,183
Fair Value Measurements on Recurring Basis
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents		47,834
Short-term investments	427,855	386,183
Cash equivalents and short-term investments	466,315	434,017
Fair Value Measurements on Recurring Basis \| Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents		37,878
Short-term investments	242,230	180,049
Cash equivalents and short-term investments	280,690	217,927
Fair Value Measurements on Recurring Basis \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents		9,956
Short-term investments	185,625	206,134
Cash equivalents and short-term investments	185,625	216,090
Fair Value Measurements on Recurring Basis \| Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	38,460	37,878
Fair Value Measurements on Recurring Basis \| Money Market Funds \| Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	38,460	37,878
Fair Value Measurements on Recurring Basis \| U.S. Treasury Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	242,230	180,049
Fair Value Measurements on Recurring Basis \| U.S. Treasury Securities \| Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	242,230	180,049
Fair Value Measurements on Recurring Basis \| Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	90,214	111,832
Fair Value Measurements on Recurring Basis \| Corporate Debt Securities \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	90,214	111,832
Fair Value Measurements on Recurring Basis \| Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	55,735	52,941
Fair Value Measurements on Recurring Basis \| Commercial Paper \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	55,735	52,941
Fair Value Measurements on Recurring Basis \| U S Agency Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents		9,956
Short-term investments	22,062	16,043
Fair Value Measurements on Recurring Basis \| U S Agency Bonds \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents		9,956
Short-term investments	22,062	16,043
Fair Value Measurements on Recurring Basis \| Non U S Government And Supranational Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	17,614	25,318
Fair Value Measurements on Recurring Basis \| Non U S Government And Supranational Debt Securities \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	$ 17,614	$ 25,318

Condensed Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid- In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balance at Dec. 31, 2021	$ 506,609	$ 7	$ 941,359	$ (1,789)	$ (432,968)
Beginning balance (in shares) at Dec. 31, 2021		66,572
Share-based compensation expense	6,650		6,650
Issuance of common stock under equity plans	303		303
Issuance of common stock under equity plans, shares		64
Other comprehensive income (loss)	(4,859)			(4,859)
Net loss	(32,453)				(32,453)
Ending balance at Mar. 31, 2022	476,250	$ 7	948,312	(6,648)	(465,421)
Ending balance (in shares) at Mar. 31, 2022		66,636
Beginning balance at Dec. 31, 2021	506,609	$ 7	941,359	(1,789)	(432,968)
Beginning balance (in shares) at Dec. 31, 2021		66,572
Net loss	(67,222)
Ending balance at Jun. 30, 2022	449,491	$ 7	957,489	(7,815)	(500,190)
Ending balance (in shares) at Jun. 30, 2022		66,838
Beginning balance at Mar. 31, 2022	476,250	$ 7	948,312	(6,648)	(465,421)
Beginning balance (in shares) at Mar. 31, 2022		66,636
Share-based compensation expense	6,508		6,508
Issuance of common stock under equity plans	2,669		2,669
Issuance of common stock under equity plans, shares		202
Other comprehensive income (loss)	(1,167)			(1,167)
Net loss	(34,769)				(34,769)
Ending balance at Jun. 30, 2022	449,491	$ 7	957,489	(7,815)	(500,190)
Ending balance (in shares) at Jun. 30, 2022		66,838
Beginning balance at Dec. 31, 2022	420,278	$ 7	997,111	(8,032)	(568,808)
Beginning balance (in shares) at Dec. 31, 2022		68,314
Share-based compensation expense	6,838		6,838
Issuance of common stock under equity plans, shares		125
Other comprehensive income (loss)	2,136			2,136
Net loss	(34,069)				(34,069)
Ending balance at Mar. 31, 2023	395,183	$ 7	1,003,949	(5,896)	(602,877)
Ending balance (in shares) at Mar. 31, 2023		68,439
Beginning balance at Dec. 31, 2022	420,278	$ 7	997,111	(8,032)	(568,808)
Beginning balance (in shares) at Dec. 31, 2022		68,314
Net loss	(71,243)
Ending balance at Jun. 30, 2023	459,678	$ 7	1,104,944	(5,222)	(640,051)
Ending balance (in shares) at Jun. 30, 2023		74,143
Beginning balance at Mar. 31, 2023	395,183	$ 7	1,003,949	(5,896)	(602,877)
Beginning balance (in shares) at Mar. 31, 2023		68,439
Share-based compensation expense	6,987		6,987
Issuance of common stock under equity plans	431		431
Issuance of common stock under equity plans, shares		43
Issuance of common stock, net of offering costs, (in shares)		5,661
Issuance of common stock, net of offering costs	60,919		60,919
Issuance of pre-funded warrants to purchase common stock, net of offering costs	32,658		32,658
Other comprehensive income (loss)	674			674
Net loss	(37,174)				(37,174)
Ending balance at Jun. 30, 2023	$ 459,678	$ 7	$ 1,104,944	$ (5,222)	$ (640,051)
Ending balance (in shares) at Jun. 30, 2023		74,143

Investments - Additional Information (Detail) $ in Thousands	6 Months Ended
	Jun. 30, 2023 USD ($) Security	Dec. 31, 2022 USD ($)
Investments, All Other Investments [Abstract]
Short-term investments with maturities less than one year	$ 368,500	$ 274,300
Short-term investments with maturities between one and two years	$ 59,400	111,900
Short-term investments maturities, description	As of June 30, 2023 and December 31, 2022, short-term investments of $368.5 million and $274.3 million, respectively, had maturities less than one year, and short-term investments of $59.4 million and $111.9 million, respectively, had maturities between one to two years.
Allowance for credit losses	$ 0	0
Available for sale securities gross unrealized loss positions	387,400
Available for sale securities gross unrealized loss positions greater than 12 months	$ 144,000
Number of available-for-sale securities \| Security	52
Accrued interest receivable on available-for-sale securities	$ 900	$ 900

Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2023	Aug. 03, 2023
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
Trading Symbol	KURA
Entity Registrant Name	KURA ONCOLOGY, INC.
Entity Central Index Key	0001422143
Entity Current Reporting Status	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Shell Company	false
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		74,236,353
Entity File Number	001-37620
Entity Tax Identification Number	61-1547851
Entity Address, Address Line One	12730 High Bluff Drive
Entity Address, Address Line Two	Suite 400
Entity Address, City or Town	San Diego
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92130
City Area Code	858
Local Phone Number	500-8800
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Security Exchange Name	NASDAQ
Entity Incorporation, State or Country Code	DE
Document Quarterly Report	true
Document Transition Report	false

Condensed Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Jun. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.0001	$ 0.0001
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	$ 0.0001	$ 0.0001
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	74,143,000	68,314,000
Common stock, shares outstanding	74,143,000	68,314,000

Share-Based Compensation - Summary of Share-based Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 6,987	$ 6,508	$ 13,825	$ 13,158
Research and development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	3,134	2,597	6,207	5,053
General and administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 3,853	$ 3,911	$ 7,618	$ 8,105

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

Investments (Tables)

6 Months Ended

Jun. 30, 2023

Investments, All Other Investments [Abstract]

Investments Measured at Fair Value on Recurring Basis

The following tables summarize, by major security type, our short-term investments that are measured at fair value on a recurring basis, in thousands:


		June 30, 2023
	Maturities (years)	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Cash equivalents:
Money market funds	1 or less	$	38,460	$	—	$	—		$	38,460

Short-term investments:
U.S. Treasury securities	2 or less		244,260		5		(2,035	)		242,230
Corporate debt securities	2 or less		92,723		—		(2,509	)		90,214
Commercial paper	1 or less		55,780		—		(45	)		55,735
U.S. Agency bonds	1 or less		22,060		17		(15	)		22,062
Non-U.S. government and supranational debt securities	1 or less		18,254		—		(640	)		17,614
Total short-term investments			433,077		22		(5,244	)		427,855
Total		$	471,537	$	22	$	(5,244	)	$	466,315


		December 31, 2022
	Maturities (years)	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Cash equivalents:
Money market funds	1 or less	$	37,878	$	—	$	—		$	37,878
U.S. Agency bonds	1 or less		9,956		—		—			9,956
Total cash equivalents			47,834		—		—			47,834

Short-term investments:
U.S. Treasury securities	2 or less		183,051		16		(3,018	)		180,049
Corporate debt securities	2 or less		115,763		—		(3,931	)		111,832
Commercial paper	1 or less		52,941		—		—			52,941
U.S. Agency bonds	1 or less		16,192		11		(160	)		16,043
Non-U.S. government and supranational debt securities	2 or less		26,268		—		(950	)		25,318
Total short-term investments			394,215		27		(8,059	)		386,183
Total		$	442,049	$	27	$	(8,059	)	$	434,017

- Definition

Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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+ Details