CalciMedica (CALC) 10-Q 11 Aug 23 2023 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2023	Aug. 04, 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	CALC
Entity Registrant Name	CalciMedica, Inc.
Entity Central Index Key	0001534133
Entity Current Reporting Status	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Common Stock, Shares Outstanding		5,661,933
Entity File Number	001-39538
Entity Tax Identification Number	45-2120079
Entity Address, Address Line One	505 Coast Boulevard South
Entity Address, Address Line Two	Suite 307
Entity Address, City or Town	La Jolla
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92037
City Area Code	858
Local Phone Number	952-5500
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 Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands		Jun. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents		$ 19,084	$ 1,327
Restricted Cash		0	149
Prepaid expenses and other current assets		961	254
Total current assets		20,045	1,730
Property and equipment, net		199	147
Right-of-use asset, net		0	48
Other assets		1	1,424
Total assets		20,245	3,349
Current liabilities:
Accounts payable		1,743	2,866
Accrued clinical trial costs		1,207	1,143
Accrued other		1,074	572
Other current liabilities		0	199
Total current liabilities		4,024	4,780
Long-term liabilities
Warrant liability		0	2,645
Convertible promissory notes		0	5,157
Total liabilities		4,024	12,582
Commitments and contingencies (Note 8)
Stockholders' equity (deficit) (1)
Preferred stock	[1]	0	0
Common stock	[1]	1	1
Additional paid-in capital	[1]	153,519	40,402
Accumulated deficit	[1]	(137,299)	(111,707)
Total stockholders' equity (deficit)	[1]	16,221	(71,304)
Total liabilities, convertible preferred stock and stockholders' equity (deficit)		20,245	3,349
Series A Convertible Preferred Stock [Member]
Convertible preferred stock
convertible preferred stock		0	19,107
Series B Convertible Preferred Stock [Member]
Convertible preferred stock
convertible preferred stock		0	8,224
Series C-1 Convertible Preferred Stock [Member]
Convertible preferred stock
convertible preferred stock		0	5,683
Series C-2 Convertible Preferred Stock [Member]
Convertible preferred stock
convertible preferred stock		0	9,563
Series D Convertible Preferred Stock [Member]
Convertible preferred stock
convertible preferred stock		$ 0	$ 19,494
[1] (1) Retroactively restated for the reverse recapitalization as described in Note 2.

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2023	Dec. 31, 2022
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred Stock, Shares Authorized	10,000,000	0
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0
Common stock par value	$ 0.0001	$ 0.0001
Common Stock, Shares Authorized	500,000,000	5,694,626
Common Stock, Shares, Issued	5,661,933	84,165
Common Stock, Shares, Outstanding	5,661,933	84,165
Series A Convertible Preferred Stock
Preferred stock, par value	$ 0.001	$ 0.001
Preferred Stock, Shares Authorized	0	25,751,716
Preferred Stock, Shares Issued	0	25,751,716
Preferred Stock, Shares Outstanding	0	25,751,716
Series B Convertible Preferred Stock
Preferred stock, par value	$ 0.001	$ 0.001
Preferred Stock, Shares Authorized	0	11,235,460
Preferred Stock, Shares Issued	0	10,667,279
Preferred Stock, Shares Outstanding	0	10,667,279
Series C-1Convertible Preferred Stock
Preferred stock, par value	$ 0.001	$ 0.001
Preferred Stock, Shares Authorized	0	8,016,886
Preferred Stock, Shares Issued	0	8,016,886
Preferred Stock, Shares Outstanding	0	8,016,886
Series C-2 Convertible Preferred Stock
Preferred stock, par value	$ 0.001	$ 0.001
Preferred Stock, Shares Authorized	0	16,291,526
Preferred Stock, Shares Issued	0	13,504,959
Preferred Stock, Shares Outstanding	0	13,504,959
Series D Convertible Preferred Stock
Preferred stock, par value	$ 0.001	$ 0.001
Preferred Stock, Shares Authorized	0	88,875,077
Preferred Stock, Shares Issued	0	26,880,040
Preferred Stock, Shares Outstanding	0	26,880,040

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ 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	$ 3,814	$ 2,259	$ 10,305	$ 5,184
General and administrative	2,769	1,330	18,618	2,616
Total operating expenses	6,583	3,589	28,923	7,800
Loss from operations	(6,583)	(3,589)	(28,923)	(7,800)
Other income (expense), net	279	(29)	163	(29)
Change in fair value of financial instruments		588	3,168	1,169
Total other income (expense), net	279	559	3,331	1,140
Net loss and comprehensive loss	$ (6,304)	$ (3,030)	$ (25,592)	$ (6,660)
Net loss per share—basic	$ (1.11)	$ (36.55)	$ (7.86)	$ (82.42)
Net loss per share—diluted	$ (1.11)	$ (36.55)	$ (7.86)	$ (82.42)
Weighted-average number of shares outstanding used in computing net loss per share—basic	5,661,933	82,923	3,255,868	80,812
Weighted-average number of shares outstanding used in computing net loss per share—diluted	5,661,933	82,923	3,255,868	80,812

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended					6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022		Jun. 30, 2023	Jun. 30, 2022
Income Statement [Abstract]
Net loss	$ (6,304)	$ (19,288)	$ (3,030)	$ (3,630)	[1]	$ (25,592)	$ (6,660)
[1] (1) Retroactively restated for the reverse recapitalization as described in Note 2.

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) (Unaudited) - USD ($)		Total		Convertible Preferred Stock	Common Stock		Additional Paid-In Capital		Accumulated Deficit
Beginning Balance at Dec. 31, 2021	[1]	$ (63,987,000)			$ 1,000		$ 39,895,000		$ (103,883,000)
Beginning Balance, Shares at Dec. 31, 2021	[1]				78,518
Temporary equity, Beginning balance at Dec. 31, 2021	[1]			84,820,880
Temporary equity, Beginning balance, shares at Dec. 31, 2021	[1]			$ 62,071
Stock issued on exercise of stock options	[1]	1,000					1,000
Stock issued on exercise of stock options, Shares	[1]				180
Stock-based compensation expense	[1]	335,000					335,000
Net loss	[1]	(3,630,000)							(3,630,000)
Temporary equity, Ending balance, shares at Mar. 31, 2022	[1]			$ 62,071
Temporary equity, Ending balance at Mar. 31, 2022	[1]			84,820,880
Ending Balance at Mar. 31, 2022	[1]	(67,281,000)			$ 1,000		40,231,000		(107,513,000)
Ending Balance, Shares at Mar. 31, 2022	[1]				78,698
Beginning Balance at Dec. 31, 2021	[1]	(63,987,000)			$ 1,000		39,895,000		(103,883,000)
Beginning Balance, Shares at Dec. 31, 2021	[1]				78,518
Temporary equity, Beginning balance at Dec. 31, 2021	[1]			84,820,880
Temporary equity, Beginning balance, shares at Dec. 31, 2021	[1]			$ 62,071
Net loss		(6,660,000)
Temporary equity, Ending balance, shares at Jun. 30, 2022				$ 62,071
Temporary equity, Ending balance at Jun. 30, 2022				84,820,880
Ending Balance at Jun. 30, 2022		(69,973,000)			$ 1,000		40,569,000		(110,543,000)
Ending Balance, Shares at Jun. 30, 2022					83,018
Beginning Balance at Mar. 31, 2022	[1]	(67,281,000)			$ 1,000		40,231,000		(107,513,000)
Beginning Balance, Shares at Mar. 31, 2022	[1]				78,698
Temporary equity, Beginning balance at Mar. 31, 2022	[1]			84,820,880
Temporary equity, Beginning balance, shares at Mar. 31, 2022	[1]			$ 62,071
Stock issued on exercise of stock options		17,000					17,000
Stock issued on exercise of stock options, Shares					4,320
Stock-based compensation expense		321,000					321,000
Net loss		(3,030,000)							(3,030,000)
Temporary equity, Ending balance, shares at Jun. 30, 2022				$ 62,071
Temporary equity, Ending balance at Jun. 30, 2022				84,820,880
Ending Balance at Jun. 30, 2022		(69,973,000)			$ 1,000		40,569,000		(110,543,000)
Ending Balance, Shares at Jun. 30, 2022					83,018
Beginning Balance at Dec. 31, 2022		(71,304,000)	[2]		$ 1,000	[3]	40,402,000	[3]	(111,707,000)	[3]
Beginning Balance, Shares at Dec. 31, 2022	[3]				84,165
Temporary equity, Beginning balance at Dec. 31, 2022	[3]			84,820,880
Temporary equity, Beginning balance, shares at Dec. 31, 2022	[3]			$ 62,071,000
Stock-based compensation expense		11,126,000					11,126,000
Conversion of preferred stock to common stock as a result of the Merger, shares					2,442,852
Conversion of preferred stock to common stock as a result of the Merger, shares				(84,820,880)
Conversion of preferred stock to common stock as a result of the Merger, value		62,071,000					62,071,000
Conversion of preferred stock to common stock as a result of the Merger, value				$ (62,071,000)
Issuance of common stock to Graybug stockholders as a result of Merger and reset to par of $0.0001, Shares					1,571,433
Issuance of common stock to Graybug stockholders as a result of Merger and reset to par of $0.0001		29,218,000					29,218,000
Issuance of common shares from private placement, net, shares					596,363
Issuance of common shares from private placement, net		10,340,000					10,340,000
Conversion of promissory notes into common stock, shares					590,031
Conversion of promissory notes into common stock		3,245,000					3,245,000
Conversion of Series C-2 Warrants into common stock, share					80,254
Conversion of Series C-2 Warrants into common stock		442,000					442,000
Conversion of promissory note warrants into common stock, shares					152,875
Conversion of promissory note warrants into common stock		841,000					841,000
Merger transaction costs		(4,591,000)					(4,591,000)
Restricted stock units net settlement, shares					143,960
Restricted stock units net settlement		(297,000)					(297,000)
Reclassification of warrant liability to equity		216,000					216,000
Net loss		(19,288,000)							(19,288,000)
Ending Balance at Mar. 31, 2023		22,019,000			$ 1,000		153,013,000		(130,995,000)
Ending Balance, Shares at Mar. 31, 2023					5,661,933
Beginning Balance at Dec. 31, 2022		(71,304,000)	[2]		$ 1,000	[3]	40,402,000	[3]	(111,707,000)	[3]
Beginning Balance, Shares at Dec. 31, 2022	[3]				84,165
Temporary equity, Beginning balance at Dec. 31, 2022	[3]			84,820,880
Temporary equity, Beginning balance, shares at Dec. 31, 2022	[3]			$ 62,071,000
Issuance of common stock to Graybug stockholders as a result of Merger and reset to par of $0.0001		29,218,000
Restricted stock units net settlement		(297,000)
Net loss		(25,592,000)
Ending Balance at Jun. 30, 2023		16,221,000	[2]		$ 1,000		153,519,000		(137,299,000)
Ending Balance, Shares at Jun. 30, 2023					5,661,933
Beginning Balance at Mar. 31, 2023		22,019,000			$ 1,000		153,013,000		(130,995,000)
Beginning Balance, Shares at Mar. 31, 2023					5,661,933
Stock-based compensation expense		463,000					463,000
Adjustment to purchase accounting		3,000					3,000
Merger transaction costs		40,000					40,000
Net loss		(6,304,000)							(6,304,000)
Ending Balance at Jun. 30, 2023		$ 16,221,000	[2]		$ 1,000		$ 153,519,000		$ (137,299,000)
Ending Balance, Shares at Jun. 30, 2023					5,661,933
[1] (1) Retroactively restated for the reverse recapitalization as described in Note 2. (1) Retroactively restated for the reverse recapitalization as described in Note 2. (1) Retroactively restated for the reverse recapitalization as described in Note 2.

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) (Unaudited) (Parenthetical) - $ / shares	Jun. 30, 2023	Mar. 31, 2023	Mar. 17, 2023	Dec. 31, 2022
Common stock par value	$ 0.0001			$ 0.0001
Graybug
Common stock par value		$ 0.0001	$ 0.0001

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended		12 Months Ended
	Mar. 31, 2023	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Operating activities:
Net loss		$ (25,592)	$ (6,660)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense		11,589	656
Depreciation and amortization		27	26
Change in the fair value of warrant liability		(1,146)	(1,169)
Change in the fair value of convertible promissory notes		(2,022)
Non-cash interest expense		110
Accretion of discount on short-term investment		(55)
Changes in operating assets and liabilities:
Prepaid expenses and other current and non-current assets		1,548	7
Accounts payable		(20)	701
Accrued expenses and other liabilities		(1,986)	597
Net cash used in operating activities		(17,547)	(5,842)
Investing activities:
Purchases of property and equipment		(78)	(4)
Maturity of investments		14,580
Net cash provided by (used in) investing activities		14,502	(4)
Financing activities:
Proceeds from issuance of common stock, net of issuance costs		10,340
Acquisition of stock of Graybug, net of cash		14,859
Merger transaction costs		(4,546)
Proceeds from issuance of convertible notes			1,290
Proceeds from exercise of stock options			17
Net cash provided by financing activities		20,653	1,307
Net increase (decrease) in cash and cash equivalents		17,608	(4,539)
Cash, cash equivalents and restricted cash at beginning of period	$ 1,476	1,476	4,761	$ 4,761
Cash and cash equivalents at end of period		19,084	$ 222	$ 1,476
Supplemental cash flow information:
Conversion of Series A, B, C-1, C-2 and D convertible preferred stock to common stock		62,071
Issuance of common stock to Graybug stockholders as a result of the Merger	29,218	29,218
Short-term investments assumed in the Merger		9,776
Prepaid expenses and other current assets assumed in the Merger		2,096
Accounts payable and accrued liabilities assumed in the Merger		2,258
Conversion of C-2 warrants to common stock		442
Conversion of convertible promissory notes to common stock		3,245
Conversion of convertible promissory note warrants to common stock		841
Merger transaction costs in accounts payable		1
Merger transaction costs in accrued expenses		4
Restricted stock units net settlement	$ 297	297
Reclassification of warrant liability to equity		$ 216

Nature of Business

Nature of Business	6 Months Ended
	Jun. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business	1. Nature of Business Description of Business CalciMedica, Inc. (“CalciMedica” or the “Company”) (f/k/a Graybug Vision, Inc.) was incorporated in the state of Delaware in February 2015, upon conversion of Graybug, LLC, which was organized in May 2011, and has its principal operations in La Jolla, California. The Company is a clinical-stage biopharmaceutical company focused on developing therapeutics that treat serious illnesses driven by inflammatory processes and direct cellular damage.​ The Company has a wholly owned subsidiary, CalciMedica Subsidiary, Inc., incorporated in Delaware in October 2006, through which it conducts substantially all its operations, which survived the Merger as more fully described below. Reverse Merger Transaction On March 20, 2023, Graybug Vision, Inc. (“Graybug”) completed a reverse merger transaction in accordance with the terms and conditions of the Agreement and Plan of Merger and Reorganization, dated as of November 21, 2022, as amended on February 10, 2023 (the “Merger Agreement”), by and among Graybug, Camaro Merger Sub, Inc., a wholly owned subsidiary of Graybug (“Merger Sub”), and CalciMedica, Inc. (“Private CalciMedica”), pursuant to which Merger Sub merged with and into Private CalciMedica, with Private CalciMedica surviving as wholly owned subsidiary of Graybug (the “Merger”). Additionally, on March 20, 2023, Graybug changed its name from “Graybug Vision, Inc.” to “CalciMedica, Inc.” and Private CalciMedica changed its name from “CalciMedica, Inc.” to “CalciMedica Subsidiary, Inc.” At the completion of the Merger, the prior Private CalciMedica equityholders and the prior Graybug equityholders owned 72 % and 28 %, respectively of the combined company, in each case, on a fully diluted basis using the treasury stock method and excluding out-of-the-money options and warrants. The Merger was accounted for as a reverse recapitalization, with Private CalciMedica being treated as the acquirer for accounting purposes. See discussions of the transactions in connection with the Merger at Note 3 - Merger and Related Transactions. Liquidity and Going Concern The Company has experienced net losses and negative cash flows from operating activities since its inception. The Company has an accumulated deficit of $ 137.3 million as of June 30, 2023, and a net loss of $ 6.3 million and $ 25.6 for the three and six months ended June 30, 2023, respectively. Total operating expenses for the three months ended June 30, 2023 were $ 6.6 million. Total operating expenses for the six months ended June 30, 2023 were $ 28.9 million, which included $ 16.2 million of one-time charges comprised of $ 10.5 million of charges related to the acceleration of vesting of the Graybug stock awards at the date of the Merger and $ 5.7 million of charges related to severance as a result of the Merger. Substantially all of Company’s operating losses resulted from expenses incurred in connection with its research and development programs and from general and administrative costs associated with its operations. The Company expects to incur significant expenses and increasing operating losses for the foreseeable future as the Company initiates and continues the preclinical and clinical development of its product candidates and adds personnel necessary to operate as a company with an advanced clinical pipeline of product candidates. In addition, after completion of the Merger, operating as a U.S. Securities and Exchange Commission (“SEC”) registrant will involve the hiring of additional financial and other personnel, upgrading financial information systems, and incurring costs associated with operating as a public company. The Company expects that its operating losses will fluctuate significantly from quarter-to-quarter and year-to-year due to timing of clinical development programs. From inception to June 30, 2023, the Company has completed financings from the sale of preferred and common stock for total gross proceeds of $ 111.7 million and has issued convertible debt for gross proceeds of $ 8.6 million. In connection with the Merger, the Company received approximately $ 29.4 million of cash, cash equivalents and short-term investments. As of June 30, 2023, the Company had cash and cash equivalents of approximately $ 19.1 million. With these funds, the Company expects to be able to fund its operations beyond 12 months from the date of the issuance of the accompanying condensed consolidated financial statements.

Summary of Significant Accounti

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 Basis of Presentation and Principles of Consolidation The condensed consolidated financial statements have been prepared in conformity with U.S. generally accepted accounting principles (“U.S. GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification (“ASC”), and Accounting Standards Update (“ASU”), of the Financial Accounting Standards Board (“FASB”). The condensed consolidated financial statements include the accounts of the Company and CalciMedica Subsidiary, Inc. for the three and six months ended June 30, 2023 and 2022. All intercompany accounts and transactions have been eliminated in consolidation. Since Private CalciMedica was determined to be the accounting acquirer in connection with the Merger, for periods prior to the Merger, the condensed consolidated financial statements were prepared on a stand-alone basis for Private CalciMedica and did not include the combined entities activity or financial position. Subsequent to the Merger, the condensed consolidated financial statements as of and for the three and six months ended June 30, 2023 include Graybug’s activity from March 21, 2023 through June 30, 2023 , and assets and liabilities at their acquisition date fair value. Historical share and per share figures of Private CalciMedica have been retroactively restated based on the exchange ratio of 0.0288 . Use of Estimates The preparation of the Company’s condensed consolidated financial statements requires management to make estimates and assumptions that impact the reported amounts of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities in the Company’s condensed consolidated financial statements and accompanying notes. The most significant estimates in the Company’s condensed consolidated financial statements relate to accruals for research and development expenses, valuation of warrants, valuation of convertible promissory notes and valuation of equity awards. These estimates and assumptions are based on current facts, historical experience and various other factors 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 and the recording of expenses that are not readily apparent from other sources. Actual results may differ materially and adversely from these estimates. To the extent there are material differences between the estimates and actual results, the Company’s future results of operations will be affected. Concentration of Credit Risk and other Risks and Uncertainties Financial instruments, which potentially subject the Company to concentration of risk, consist principally of cash and cash equivalents. The Company’s cash is deposited with major federally insured U.S. financial institutions. The Company has no off-balance sheet concentrations of credit risk, such as foreign currency exchange contracts, option contracts or other hedging arrangements. The Company is dependent on contract manufacturing organizations (“CMO”) to supply products for research and development of its product candidates, including preclinical and clinical studies, and for commercialization of its product candidates, if approved. The Company’s development programs could be adversely affected by any significant interruption in CMO’s operations or by a significant interruption in the supply of active pharmaceutical ingredients and other components. Products developed by the Company require approval from the U.S. Food and Drug Administration (“FDA”) or other international regulatory agencies prior to commercial sales. There can be no assurance the Company’s product candidates will receive the necessary approvals. If the Company is denied approvals, approvals are delayed, or the Company is unable to maintain approvals received, such events could have a materially adverse impact on the Company. Cash and Cash Equivalents Cash and cash equivalents consist of readily available cash in checking accounts and money market funds. The Company considers all highly liquid investments with an original maturity of three months or less from the date of purchase to be cash equivalents. Short-term Investments The Company invests excess cash in marketable government agency bonds and commercial paper. These investments are included in short-term investments on the balance sheets, classified as available-for-sale and reported at fair value with unrealized gains and losses included in accumulated other comprehensive loss. Realized gains and losses on the sale of these securities are recognized in net loss. As of June 30, 2023, the Company’s short-term investments had converted to cash and cash equivalents. Segment Information The Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions. The financial information is regularly reviewed by the chief operating decision maker (“CODM”), in deciding how to allocate resources. The Company’s CODM is its chief executive officer. The Company’s singular focus is on developing highly selective calcium release-activated calcium channel inhibitors to improve outcomes for patients with acute inflammatory indications. No significant revenue has been generated since inception, and all tangible assets are held in the United States. Fair Value Option As permitted under ASC 825, Financial Instruments , the Company has elected the fair value option to account for its convertible promissory notes due to certain embedded features within the notes. The Company recognizes the convertible promissory notes at fair value with changes in fair value recognized in the condensed consolidated statements of operations located on the change in fair value of financial instruments line item. Changes in fair value as a result of the Company’s own credit risk is reflected in other income (expense) in the condensed consolidated statements of operations. As a result of applying the fair value option, direct costs and fees related to the convertible promissory notes were expensed as incurred and not deferred. Property and Equipment Property and equipment are recorded at cost and depreciated using the straight-line method over the estimated useful lives of the assets (generally three to five years) and consist of manufacturing and lab equipment, furniture, computers and phones. Repairs and maintenance costs are charged to expense as incurred. Leases The Company leases office space with an original lease terms of twelve months . The office lease term has a twelve-month term and does no t have a right-of-use asset or lease liability recorded. The Company's policy is not to record leases with an original term of twelve months or less on the consolidated balance sheets. The Company recognizes lease expense for this short-term lease on a straight-line basis over the term of the lease. The lease is accounted for under ASC 842, Leases , and has been classified as an operating lease. The Company records rent expense on a straight-line basis over the term of the lease. Long-lived Assets Long-lived assets consist primarily of property and equipment. The Company reviews long-lived assets for impairment whenever events or changes in circumstances indicate the carrying amount of an asset is not recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to the future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured as the amount by which the carrying amount of the asset exceeds the fair value of the assets. Fair value would be assessed using discounted cash flows or other appropriate measures of fair value. The Company did not recognize any impairment losses for the three and six months ended June 30, 2023 and 2022 . Research and Development Costs Research and development costs consist primarily of salaries, payroll taxes, employee benefits and stock-based compensation for those individuals involved in ongoing research and development efforts, as well as fees paid to consultants, external research fees, license fees paid to third parties for use of their intellectual property, laboratory supplies and development of compound materials, associated overhead expenses and facilities and depreciation costs. Nonrefundable advance payments for goods and services that will be used in future research and development activities are expensed when the activity has been performed or when the goods have been received rather than when the payment is made. All research and development costs are expensed as incurred. The Company estimates preclinical studies and clinical trial expenses based on the services performed pursuant to contracts with research institutions and clinical research organizations that conduct and manage preclinical studies and clinical trials on the Company’s behalf. In accruing service fees, the Company estimates the time period over which services will be performed and the level of effort to be expended in each period. These estimates are based on communications with the third-party service providers, the Company’s estimates of accrued expenses and on information available at each balance sheet date. If the actual timing of the performance of services or the level of effort varies from the estimate, the Company will adjust the accrual accordingly. The estimates are trued up to reflect the best information available at the time of the financial statement issuance. Although the Company does not expect its estimates to be materially different from amounts actually incurred, the Company’s estimate of the status and timing of services performed relative to the actual status and timing of services performed may vary. General and Administrative Costs General and administrative expenses consist primarily of salaries and related benefits, including stock-based compensation, related to our executive, finance, business development, legal, human resources and support functions, including professional fees for auditing, tax, consulting and patent-related services, rent and utilities and insurance. Patent Costs Costs related to filing and pursuing patent applications are expensed as incurred since recoverability of such expenditures is uncertain. Deferred Offering Costs The Company capitalizes costs that are directly associated with equity financings until such financings are consummated at which time such costs are recorded against the gross proceeds of the offering. Should an in-process equity financing be abandoned, the deferred offering costs will be expensed immediately as a charge to operating expenses in the statements of operations and comprehensive loss. Private CalciMedica had deferred offering costs capitalized as of December 31, 2022 for the Merger of $ 1.4 million and $ 1.1 million for a proposed initial public offering (“IPO”) as of December 31, 2021. In September 2022, Private CalciMedica terminated its plan for an IPO and expensed $ 1.5 million to general and administrative expense. Warrant Liability Private CalciMedica has issued various freestanding warrants to purchase shares of its convertible preferred stock. Prior to the Merger, Private CalciMedica adjusted the carrying value of such convertible preferred stock warrants to the estimated fair value at each reporting date, with any related increases or decreases in the fair value being recorded within other income (expense) in the condensed consolidated statements of operations and comprehensive loss. Pursuant to the Merger Agreement, the Series C convertible preferred stock warrants became warrants to purchase shares of the combined company's common stock. As a result of the Merger, the warrants no longer meet the requirements for liability accounting and, as such, Private CalciMedica adjusted the value of the warrants to the estimated fair value as of the Merger date and reclassified them to stockholders' equity (deficit). Stock-Based Compensation Stock-based compensation expense represents the cost of the grant date fair value of employee stock options recognized over the requisite service period of the awards (usually the vesting period) on a straight-line basis. Private CalciMedica estimates the fair value of stock option grants using the Black-Scholes option pricing model (“Black-Scholes”). Forfeitures are recognized as a reduction of stock-based compensation expense as they occur. Equity-based compensation expense is classified in the statements of operations in the same manner in which the award recipients’ payroll costs are classified or in which the award recipients’ service payments are classified. The fair value of each stock option grant is estimated on the date of grant using Black Scholes. The following summarizes the inputs used: Fair Value of Common Stock Prior to the Merger, there was no public market for Private CalciMedica’s common stock. The fair value of the shares of common stock underlying Private CalciMedica ’s share-based awards was estimated on each grant date by Private CalciMedica’s board of directors. To determine the fair value of Private CalciMedica’s common stock underlying option grants, the board of directors considered, among other things, input from management and valuations of Private CalciMedica's common stock prepared by third-party valuation firms. Post Merger, CalciMedica will use the closing stock price the day prior to the grant date for the fair value. Risk-Free Interest Rate The risk-free interest ra te is based on the U.S. Treasury yield in effect at the time of grant for zero coupon U.S. Treasury notes with maturities similar to the expected term of the awards. Expected Volatility Since Private CalciMedica did not have publicly traded equity securities, the volatility of the options has been estimated using peer group volatility information. Post Merger, CalciMedica will use an average volatility for comparable publicly-traded biopharmaceutical companies over a period equal to the expected term of the stock award grant as CalciMedica does not yet have sufficient historical trading history for its own stock. CalciMedica will continue to apply this method until a sufficient amount of historical information over a period equal to the expected term of the stock-based awards becomes available. Expected Term CalciMedica used the simplified method to calc ulate the expected term for all grants during all periods, which is based on the midpoint between the vesting date and the end of the contractual term. Expected Dividend Yield CalciMedica has never paid and has no present intention to pay cash dividends. Income Taxes The Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, deferred tax assets and liabilities are determined on the basis of the differences between the financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. The Company recognizes net deferred tax assets to the extent that the Company believes these assets are more likely than not to be realized. In making such a determination, management considers all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning strategies, and results of recent operations. If management determines that the Company would be able to realize its deferred tax assets in the future in excess of their net recorded amount, management would make an adjustment to the deferred tax asset valuation allowance, which would reduce the provision for income taxes. The Company records uncertain tax positions on the basis of a two-step process whereby (1) management determines whether it is more likely than not that the tax positions will be sustained on the basis of the technical merits of the position and (2) for those tax positions that meet the more-likely-than-not recognition threshold, management recognizes the largest amount of tax benefit that is more than 50 % likely to be realized upon ultimate settlement with the related tax authority. The Company recognizes interest and penalties related to unrecognized tax benefits within income tax expense. Any accrued interest and penalties are included within the related tax liability. Comprehensive Loss Comprehensive loss is defined as a change in equity during a period from transactions and other events and circumstances from non-owner sources. The Company’s comprehensive loss was the same as its reported net loss for all periods presented. Related Party Transactions The Company’s board of directors reviews and approves transactions with directors, officers and holders of 5 % or more of its voting securities and their affiliates, each a related party. The material facts as to the related party’s relationship or interest in the transaction are disclosed to its board of directors prior to their consideration of such transaction, and the transaction is not considered approved by its board of directors unless a majority of the directors who are not interested in the transaction approve the transaction. Beginning in November 2020, Private CalciMedica has paid consulting fees monthly to a consulting firm affiliated with the Company’s interim chief financial officer in connection with its consulting agreement. Private CalciMedica recorded expense of $ 227,000 a nd $ 58,000 during the three months ended June 30, 2023 and 2022 , respectively, and $ 346,000 and $ 100,000 during the six months ended June 30, 2023 and 2022 , respectively. Net Loss Per Share Net loss is equivalent to net loss attributable to common stockholders for all periods presented. Basic net loss per share is computed using the weighted average number of shares of common stock outstanding during the period. The Company calculates diluted net loss per share using the more dilutive of the (1) treasury stock method, if-converted method, or contingently issuable share method, as applicable, or (2) the two-class method. For warrants, the calculation of diluted net loss per share requires that, to the extent the average fair value of the underlying shares for the reporting period exceeds the exercise price of the warrants and the presumed exercise of such securities are dilutive to net loss per share for the period, adjustments to net loss used in the calculation are required to remove the change in fair value of the warrants for the period. In all periods presented, the Company’s outstanding preferred stock, stock options, preferred, common and convertible promissory note warrants, and outstanding convertible promissory notes were excluded from the calculation of loss per share because the effect would be antidilutive. Accordingly, in periods in which the Company reports a net loss, diluted net loss per share is the same as basic net loss per share. Recently Issued Accounting Pronouncements In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments , which changes the accounting for recognizing impairments of financial assets. Under the new guidance, credit losses for certain types of financial instruments will be estimated based on expected losses. The new guidance also modifies the impairment models for available-for-sale debt securities and for purchased financial assets with credit deterioration since their origination. This update is effective for the Company beginning January 1, 2023. The Company adopted this ASU as of January 1, 2023, which did not have an impact on its condensed consolidated financial statements and related disclosures. In August 2020, the FASB issued ASU 2020-06, Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40) . The ASU provides guidance that simplified the accounting for certain financial instruments with characteristics of liabilities and equity. The new guidance reduced the number of accounting models for convertible debt and convertible preferred stock instruments and made certain disclosure amendments intended to improve the information provided to users. The guidance also amended the derivative guidance for the “own stock” scope exception, which exempts qualifying instruments from being accounted for as derivatives if certain criteria are met. Finally, the standard changed the way certain convertible instruments are treated when calculating earnings per share. This guidance is effective for fiscal years beginning after December 15, 2023, including interim periods within those fiscal years, with early adoption permitted. The Company is currently assessing the impact that this guidance will have on its condensed consolidated financial statements.

Merger and Related Transactions

Merger and Related Transactions	6 Months Ended
	Jun. 30, 2023
Business Combinations [Abstract]
Merger and Related Transactions	3. Merger and Related Transactions As described in Note 1 - Nature of Business, Private CalciMedica merged with a wholly owned subsidiary of Graybug on March 20, 2023. The Merger was accounted for as a reverse recapitalization under U.S. GAAP. Private CalciMedica was considered the accounting acquirer for financial reporting purposes. This determination is based on the facts that, immediately following the Merger: (i) former Private CalciMedica stockholders owned a substantial majority of the voting rights of the combined company; Private CalciMedica designated a majority (five of seven) of the initial members of the board of directors of the combined company; and former Private CalciMedica's senior management held all key positions in senior management of the combined company. The transaction is accounted for as a reverse recapitalization of Graybug by Private CalciMedica similar to the issuance of equity for the net assets of Graybug, which are primarily cash, short-term investments and other non-operating assets. It was concluded that any in-process research and development assets that remained as of the Merger would be de minimis when compared to the cash and investments obtained through the Merger. Under reverse recapitalization accounting, the assets and liabilities of Graybug were recorded at their fair value, which approximated book value due to the short-term nature of the instruments. The Company's condensed consolidated financial statements reflect the issuance of 1,571,433 shares to the former stockholders of Graybug. Under the terms of the Merger Agreement, immediately prior to the effective time of the Merger, each outstanding share of Private CalciMedica capital stock (after giving effect to the automatic conversion of all shares of Private CalciMedica preferred stock into shares of Private CalciMedica common stock, the automatic exercise of certain Private CalciMedica warrants to purchase shares of Private CalciMedica common stock in accordance with their terms (the “Private CalciMedica warrant exercises”), the conversion of Private CalciMedica convertible promissory notes into Private CalciMedica common stock and the closing of the private placement (as discussed in Note 6 - Convertible Preferred Stock, Common Stock, and Stockholders' Deficit)), was converted into the right to receive 0.0288 shares of Graybug common stock, which resulted in the issuance by Graybug of an aggregate of 3,946,540 shares of Graybug common stock to the stockholders of Private CalciMedica in a transaction exempt from registration under the Securities Act of 1933, as amended (the “Securities Act”), in reliance on Section 4(a)(2) of the Securities Act and the rules promulgated thereunder. In addition, Graybug assumed the Private CalciMedica 2006 Stock Plan (See Note 7 - Stock-Based Compensation), and each outstanding and unexercised option to purchase Private CalciMedica common stock and each outstanding and unexercised warrant to purchase Private CalciMedica common stock (excluding the warrants which were automatically exercised pursuant to the Private CalciMedica warrant exercises) became options and warrants, respectively, to purchase shares of Graybug common stock. Immediately following the consummation of the Merger prior Private CalciMedica and Graybug stockholders collectively own approximately 72 % and 28 % of the Company, respectively, on a fully diluted basis. As part of the reverse recapitalization, Private CalciMedica received $ 29.4 million of cash, cash equivalents and short-term investments, net of transaction costs. Private CalciMedica also obtained prepaid and other current assets of approximately $ 2.1 million and assumed payables and accrued expenses of approximately $ 2.3 million. Private CalciMedica also incurred transaction costs of approximately $ 4.6 million, which is recorded as a reduction to additional paid-in capital in the accompanying condensed consolidated statement of convertible preferred stock and stockholders' equity (deficit). The Company also recorded one-time charges of $ 10.5 million for the acceleration of the Graybug stock awards and $ 5.7 million in severance charges that are recorded in the condensed consolidated statements of operations and comprehensive loss for the six months ended June 30, 2023. On March 17, 2023, in connection with the transactions contemplated by the Merger Agreement and following a special meeting of Graybug’s stockholders, Graybug filed an Amended and Restated Certificate of Incorporation effecting a reverse stock split of Graybug’s common stock, par value $ 0.0001 per share, at a ratio of 14 :1 (“Reverse Stock Split”).

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurements	4. Fair Value Measurements The Company's assets and liabilities which are measured at fair value include warrants for preferred stock (“Preferred Warrants”), warrants for common stock related to the convertible promissory notes (“Convertible Promissory Note Warrants”), presented together on the balance sheets as “Warrant Liability” and convertible promissory notes. All assets and liabilities recorded at fair value are revalued at each measurement period. Private CalciMedica elected the fair value option for the convertible promissory notes and estimated the fair value based on a discounted cash flow analysis, a form of the Income Approach. Several different settlement scenarios were considered, and probability weighted to arrive at the final valuation. Increases or decreases in the fair value of the convertible promissory notes can result from updates to assumptions such as the expected timing or probability of the different settlement scenarios, or changes in discount rates. Judgment is used in determining these assumptions as of the initial valuation date and at each subsequent reporting period. Updates to assumptions could have a significant impact on our results of operations in any given period. The Preferred Warrants are valued using the Hybrid Method (“Hybrid Method”). This method incorporates Private CalciMedica’s near-term liquidity event prospects utilized in conjunction with the Option Pricing Method (“OPM”) framework, representing an alternative exit, to calculate an implied overall value of Private CalciMedica. This value is, in turn, allocated to Private CalciMedica’s various equity classes. The Convertible Promissory Note Warrants are valued using a series of Monte Carlo simulations and Black-Scholes to determine the fair value, probability weighted for difference scenarios. The Monte Carlo simulations determined the liquidity event price. Black-Scholes is used with the remaining contractual term of the warrants after the respective event date. The warrant value is discounted from the respective event date using the risk-free rate for the period ending December 31, 2022. As of March 31, 2023, the Convertible Promissory Note Warrants were valued using the common stock price on day of conversion. See further discussion in Note 5 - Convertible Promissory Notes and Convertible Promissory Note Warrants. The Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible. The Company determines fair value based on assumptions that market participants would use in pricing an asset or liability in the principal or most advantageous market. When considering market participant assumptions in fair value measurements, the following fair value hierarchy distinguishes between observable and unobservable inputs, which are categorized in one of the following three levels: • Level 1: Observable inputs such as unadjusted quoted prices in active markets for identical assets or liabilities at the measurement date. • Level 2: Inputs (other than quoted prices included in Level 1) that are either directly or indirectly observable for the asset or liability. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active. • Level 3: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. The following tables present information about the Company’s financial assets measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): June 30, 2023 Level 1 Level 2 Level 3 Total Current assets: Cash equivalents: Money market funds $ 18,699 $ — $ — $ 18,699 Total cash equivalents 18,699 — — 18,699 Total assets measured at fair value $ 18,699 $ — $ — $ 18,699 No fair value liabilities exist as of June 30, 2023. December 31, 2022 Level 1 Level 2 Level 3 Total Liabilities: Convertible promissory notes $ — $ — $ 5,157 $ 5,157 Preferred Warrants liability — — 1,453 1,453 Convertible Promissory Note Warrants liability — — 1,192 1,192 Total liabilities measured at fair value $ — $ — $ 7,802 $ 7,802 The following provides a reconciliation for all liabilities measured at fair value using Level 3 inputs for the six months ended June 30, 2023 (in thousands): Convertible Promissory Note liability Balance at December 31, 2022 $ 5,157 Change in Fair Value of Convertible Promissory Notes ( 2,022 ) Accrued Interest 110 Conversion of Convertible Promissory Notes to equity ( 3,245 ) Balance at June 30, 2023 $ — Preferred Warrant liability Balance at December 31, 2022 $ 1,453 Change in Fair Value of Preferred Warrants ( 795 ) Conversion of warrant liability to equity ( 658 ) Balance at Jane 30, 2023 $ — Convertible Promissory Note Warrants liability Balance at December 31, 2022 $ 1,192 Change in Fair Value of Convertible Promissory Note Warrants ( 351 ) Conversion of Convertible Promissory Note Warrants liability to equity ( 841 ) Balance at June 30, 2023 $ — Money market funds are highly liquid investments which are actively traded. The pricing information on the Company’s money market funds are based on quoted prices in active markets for identical securities. This approach results in the classification of these securities as Level 1 of the fair value hierarchy. As of December 31, 2022 , there were no cash equivalents.

Convertible Promissory Notes an

Convertible Promissory Notes and Convertible Promissory Note Warrants	6 Months Ended
	Jun. 30, 2023
Debt Disclosure [Abstract]
Convertible Promissory Notes and Convertible Promissory Note Warrants	5. Convertible Promissory Notes and Convertible Promissory Note Warrants In April 2022, the Private CalciMedica board of directors approved a convertible promissory note financing pursuant to which it could issue and sell up to $ 5.0 million of notes convertible into shares of common stock (the “convertible promissory notes”) and Convertible Promissory Note Warrants. The funding and issuance of the convertible promissory notes for gross proceeds of $ 3.5 million and Convertible Promissory Note Warrants to purchase shares of the Private CalciMedica’s common stock at an exercise price of $ 0.01 per share took place in multiple closings through October 2022. In November 2022, the Private CalciMedica board of directors amended the convertible promissory notes and Convertible Promissory Note Warrants to issue up to an additional $ 3.5 million (for a total of up to $ 8.5 million) and added the automatic conversion for a “de-SPAC” business combination or reverse merger transaction. In November 2022, Private CalciMedica issued additional convertible promissory notes for gross proceeds of $ 5.0 million and Convertible Promissory Note Warrants to purchase shares of Private CalciMedica’s common stock at an exercise price of $ 0.01 per share. The convertible promissory notes accrued interest at a rate of 6 % per annum and had a maturity date of December 31, 2023. Immediately prior to the effective time of the Merger, all outstanding convertible promissory notes and unpaid and accrued interest automatically converted into 20,487,104 shares of Private CalciMedica’s common stock at a conversion price based on the equivalent valuation of the cash price paid per share by the private placement investors purchasing shares of common stock in the private placement multiplied by 0.85 . Such shares of common stock were then converted into 590,031 shares of Graybug common stock at the effective time of the Merger in accordance with the Merger Agreement. In connection with each purchase of a convertible promissory note, Private CalciMedica issued to each holder of such convertible promissory note Convertible Promissory Note Warrant to purchase shares of the Private CalciMedica’s common stock at an exercise price of $ 0.01 per share. Each holder of the Convertible Promissory Note Warrants had the right to purchase up to a number of shares of Private CalciMedica’s common stock equal to (i) 15 % (“Warrant Coverage”) of the principal amount of the convertible promissory note purchased by such holder concurrently therewith, divided by (ii) the cash price paid per share by the investors in the qualified financing or an initial public offering, as applicable, or in the case of a “de-SPAC” business combination or a reverse merger transaction between Private CalciMedica and a publicly traded company (a “Public Combination”), the equivalent valuation of the lower of the cash price per share by the investors purchasing shares in the publicly traded company in connection with such Public Combination or the cash price per shares by the investors purchasing shares of Private CalciMedica’s common stock in connection with such Public Combination, in each case, rounding down to the nearest whole share and subject to the terms of the convertible promissory notes; provided, however, that any holder that purchased convertible promissory notes in excess of the holder’s pro rata commitment (as defined in the convertible promissory notes) received a 40 % Warrant Coverage on the principal amount of the convertible promissory notes that is in excess of its pro rata commitment. The Convertible Promissory Note Warrants had a five-year term. In connection with the Merger, the Convertible Promissory Note Warrants were automatically net exercised in accordance with the terms of the Convertible Promissory Note Warrants. Immediately prior to the effective time of the Merger, 5,308,047 Convertible Promissory Note Warrants were converted into 5,308,047 shares of Private CalciMedica's common stock, which were converted into 152,875 shares of Graybug's common stock, based on the principal amount of the convertible promissory note. Prior to the Merger, the Convertible Promissory Note Warrants were not deemed equity and were classified as a liability in Private CalciMedica’s balance sheets. The Convertible Promissory Note Warrants were valued using a series of Monte Carlo simulations and Black-Scholes to determine the fair value, probability weighted for difference scenarios. The Monte Carlo simulations determined the liquidity event price. The Black-Scholes warrant value is discounted from the respective event date using the risk-free rate. The Black-Scholes valuation included standard assumptions such as exercise price, expected term, risk-free rate, volatility, and a dividend yield of zero. Private CalciMedica estimated the initial fair value of the Convertible Promissory Note Warrants utilizing the following range of assumptions for the difference scenarios: exercise price ($ 0.01 ), risk-free rate ( 3.02 % - 4.20 %), volatility ( 63 % - 67 %), and expected term ( 4.1 - 4.6 years). As of the date of the Merger, Private CalciMedica revalued the Convertible Promissory Note Warrants which were converted into 152,871 shares of common stock, using the price of the common stock of Graybug of $ 5.50 .

Convertible Preferred Stock, Co

Convertible Preferred Stock, Common Stock and Stockholders' Deficit	6 Months Ended
	Jun. 30, 2023
Temporary Equity Disclosure [Abstract]
Convertible Preferred Stock, Common Stock and Stockholders' Deficit	6. Convertible Preferred Stock, Common Stock and Stockholders' Deficit Authorized Shares The Company's current Amended and Restated Certificate of Incorporation authorizes 500,000,000 shares of common stock, par value $ 0.0001 per share, and 10,000,000 shares of preferred stock, par value $ 0.0001 per share. Convertible Preferred Stock Private CalciMedica's convertible preferred stock consisted of Series A preferred stock (“Series A preferred”), Series B preferred stock (“Series B preferred”), Series C-1 preferred stock (“Series C-1 preferred”), Series C-2 preferred stock (“Series C-2 preferred”) and Series D preferred stock (“Series D preferred”). In February 2021, Private CalciMedica completed closings of an aggregate of 8,152,834 shares of its Series D preferred at a purchase price of $ 0.8045 per share for aggregate gross proceeds of approximately $ 6.6 million. From March 2021 to July 2021, Private CalciMedica completed subsequent closings as follows: (i) an aggregate of 5,069,660 additional shares of its Series D preferred were sold in March 2021 at a purchase price of $ 0.8045 per share for aggregate gross proceeds of approximately $ 4.1 million, (ii) an aggregate of 12,911,742 additional shares of its Series D preferred were sold in June 2021 at a purchase price of $ 0.8045 per share for aggregate gross proceeds of approximately $ 10.4 million and (iii) an aggregate of 745,804 additional shares of its Series D preferred were sold in July 2021 at a purchase price of $ 0.8045 per share for aggregate gross proceeds of approximately $ 0.6 million. In connection with the closing of the Series D preferred, Private CalciMedica issued warrants (“Series D Warrant”) to purchase Series D preferred at an exercise price of $ 0.8045 per share. The Series D Warrant was recorded as a warrant liability in Private CalciMedica’s balance sheet. The proceeds from the Series D preferred issuance were reduced by the fair value of the Series D Warrant. The fair value of the Series D Warrant was determined to be $ 1.8 million using the Hybrid Method, which allocates the various series of preferred and common stock based on their respective seniority, liquidation preferences or conversion rates, whichever is greatest. Immediately prior to the effective time of the Merger, the 84,820,880 shares of Private CalciMedica preferred stock were converted into 84,820,880 outstanding shares of Private CalciMedica's common stock to be exchanged for 2,442,852 shares of Graybug's common stock. Classification of Convertible Preferred Stock Private CalciMedica's convertible preferred stock as of December 31, 2022, was classified outside of stockholders’ equity (deficit) on the accompanying balance sheets because such shares have liquidation rights in the event of a deemed liquidation that, in certain situations, are not solely within the control of Private CalciMedica and would require the redemption of the then outstanding shares of convertible preferred stock. Convertible preferred stock was not redeemable, except in the event of a deemed liquidation. Because the occurrence of a deemed liquidation event was not probable, the carrying values of the convertible preferred stock were not being accreted to their redemption values. Subsequent adjustments to the carrying values of the convertible preferred stock would be made only when a deemed liquidation event became probable. Common Stock Upon completion of the Merger on March 20, 2023, as the accounting acquirer, Private CalciMedica is deemed to have issued 1,571,433 shares of its common stock to Graybug shareholders. Private Placement of Common Stock Immediately prior to the consummation of the Merger, Private CalciMedica completed a private placement financing pursuant to which certain investors purchased approximately 20.7 million shares of Private CalciMedica’s common stock (the “private placement”) for gross proceeds of approximately $ 10.3 million. In conjunction with the Merger, immediately prior to the effective time of the Merger, 20,706,997 shares of Private CalciMedica common stock were converted into 596,363 shares of Graybug’s common stock. Preferred and Common Stock Warrants In connection with the issuance of convertible notes in 2016, 568,181 warrants to purchase Series B preferred were issued at an exercise price of $ 0.77 per share (the “Series B Warrants”). The Series B Warrants were exercisable at any time after February 28, 2017, through the earliest to occur of ten years after the issue date or prior to the date of sale of common stock in an initial public offering or a deemed liquidation event. Until the Merger, these Series B Warrants were accounted for as a liability and had a fair value of $ 45,000 at December 31, 2022 . Prior to the Merger, the Series B Warrants converted into 568,181 common share warrants of Private CalciMedica. In conjunction with the Merger, the common warrants converted into 16,366 common share warrants of CalciMedica with an exercise price of $ 26.74 and have been reclassified to stockholders' equity (deficit) at its fair value of $ 21,000 . In connection with the issuance of Series C-2 preferred in May 2020, Private CalciMedica issued a warrant (“Series C-2 Warrant”), which was exercisable for 2,786,567 shares of Series C-2 preferred at an exercise price of $ 0.77 per share. The Series C-2 Warrant was exercisable at any time after May 20, 2020, through the earliest to occur of ten years after the issue date or prior to the date of a deemed liquidation, public combination or an initial public offering. In the event of a deemed liquidation, public combination or an initial public offering, the entire 2,786,567 shares of Series C-2 preferred would automatically be issued by Private CalciMedica in exchange for the cancellation of the Series C-2 Warrant, for no additional consideration. The Series C-2 Warrants converted into 80,254 shares of common stock in connection with the Merger at a fair value of $ 0.4 million. The Series C-2 Warrant was accounted for as a liability and had a fair value of $ 0.9 million at December 31, 2022. In connection with the issuance of Series D preferred in 2021, Private CalciMedica issued warrants (“Series D Warrants”) to purchase 8,063,998 shares of Series D preferred with an exercise price of $ 0.8045 per share. The Series D Warrants were exercisable at any time after the date of issuance through the earliest to occur of five years after the issue date or prior to the date of sale of common stock in an initial public offering or a deemed liquidation. Prior to the Merger, the Series D Warrants converted into 8,063,998 common share warrants of Private CalciMedica. In conjunction with the Merger, the common share warrants were converted into 232,256 common share warrants of CalciMedica with an exercise price of $ 27.94 and have been reclassified to stockholders' equity (deficit) at a fair value of $ 0.2 million. Up until the Merger, the Series D Warrants were accounted for as a liability and had a fair value of $ 0.6 million at December 31, 2022. The Company recognized a total change in fair value of the preferred stock warrants $ 0 and $ 588,000 for the three months ended June 30, 2023 and 2022 , respectively and $ 796,000 and $ 1.2 million for the six months ended June 30, 2023 and 2022, respectively. In November 2020, Private CalciMedica granted a warrant to purchase 400,000 shares of common stock to a consulting firm affiliated with its interim chief financial officer in connection with its consulting agreement. The warrant has a 10 -year term, an exercise price of $ 0.19 , and vests ratably over 24 months commencing on the effective date. At the date of issuance, the fair value of the warrant was determined to be $ 120,000 , utilizing Black-Scholes with the following assumptions: expected term of ten years , risk-free rate of 0.96 %, volatility of 80.0 % and a dividend yield of zero , which has been recognized as general and administrative expense over the vesting period. In conjunction with the Merger, the warrant converted to 11,520 warrants of CalciMedica at an exercise price of $ 6.60 . The warrant is classified as equity and the Company expensed $ 13,000 and $ 15,000 to general and administrative expense related to this warrant for the three months ended June 30, 2023 and 2022 , respectively, and $ 25,000 and $ 30,000 for the six months ended June 30, 2023 and 2022, respectively. In October 2022, Private CalciMedica granted warrants to certain officers and directors to purchase 496,970 shares of common stock. The warrants have a 10 -year term, an exercise price of $ 10.42 , and vest ratably over 12 and 48 months. At the date of issuance, the fair value of the warrants collectively was $ 125,000 and was determined utilizing Black-Scholes and will be recognized as general and administrative expense over the vesting periods. Assumptions used in the valuation were as follows: expected term of ten years , risk free rate of 4.10 %, volatility of 82 % and a dividend yield of zero . In conjunction with the Merger, the warrants converted to 14,313 warrants of CalciMedica at an exercise price of $ 10.42 . The warrants are classified as equity, and the Company expensed $ 14,000 and $ 28,000 , to general and administrative expense in the three and six months ended June 30, 2023 , respectively.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2023
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation	7. Stock-Based Compensation 2006 Equity Incentive Plan and Amendment to 2006 Plan Private CalciMedica adopted an equity incentive plan in 2006 (“2006 Plan”) that provides for the issuance of common stock to employees, non-employee directors and consultants. Recipients of incentive stock options are eligible to purchase common stock at an exercise price equal to no less than the estimated fair market value of such stock on the date of grant. The 2006 Plan provides for the grant of incentive stock options, non-statutory stock options and stock purchase rights. The maximum contractual term of options granted under the 2006 Plan is ten years . The options generally vest 25 % on the first anniversary of the grant date, with the balance vesting ratably over the following 36 months. Pursuant to the Merger Agreement, Graybug assumed the 2006 Plan and all stock options issued and outstanding under the 2006 Plan. On December 6, 2022, the Private CalciMedica board of directors approved an amendment to the 2006 Plan to increase the cumulative number of shares of common stock reserved for issuance thereunder by 180,245 shares. 2023 Equity Incentive Plan The Company adopted 2023 Equity Incentive Plan (the “2023 Plan”), which became effective at the closing of the Merger. As of the effective time of the Merger, there were 1,000,000 shares of the Company’s common stock available for grant under the 2023 Plan. In addition, the share reserve is subject to annual increases each January 1 for the first ten years following approval of the 2023 Plan of up to 5 % of shares of the Company’s common stock outstanding (or a lesser number determined by the Company’s board of directors). As of June 30, 2023 , 394,309 shares were available for grant under the 2023 Plan. 2023 Employee Stock Purchase Plan The Company adopted the 2023 Employee Stock Purchase Plan (the “2023 ESPP”) which became effective at the closing of the Merger. As of the effective time of the Merger, there were 65,000 shares of the Company’s common stock reserved for issuance under the 2023 ESPP. In addition, the share reserve is subject to annual increases each January 1 for the first ten years following approval of the 2023 ESPP of the lesser of (1) 1 % of the total number of shares of the Company’s common stock outstanding on December 31 of the preceding calendar year, (2) 195,000 shares of the Company’s common stock, or (3) such lesser number of shares of the Company’s common stock as determined by the Company’s board of directors. As of June 30, 2023 , no shares have been issued under the 2023 ESPP. The following table summarizes the stock option transactions for the 2006 and 2023 Plan: Total Options Weighted Average Exercise Price Weighted Average Remaining Contractual Term (years) Aggregate Intrinsic Value (in thousands) Outstanding at December 31, 2022 739,511 $ 6.94 7.36 $ 8,903 Assumed in the Merger 310,431 76.72 Granted 785,922 6.48 Forfeited ( 96,117 ) 70.79 Outstanding at June 30, 2023 1,739,747 $ 15.71 7.50 $ 624 Vested and exercisable at June 30, 2023 811,701 $ 6.01 6.70 $ 231 There were no options exercised during the six months ended June 30, 2023. The weighted-average fair value of options granted during the six months ended June 30, 2023 and 2022 was $ 4.47 and $ 14.24 per share, respectively. The total fair value of shares vested was $ 11.6 million (includes $ 10.5 million related to the acceleration of vesting of the Graybug stock awards at the date of the Merger) for the six months ended June 30, 2023 and $ 0.5 million for six months ended June 30, 2022. As of June 30, 2023 , stock-based compensation not yet recognized is $ 4.4 million, which the Company expects to recognize over an estimated weighted-average term of 2.9 years. The following is the range of underlying assumptions in Black-Scholes to determine the fair value of the stock option grants for the six months ended June 30, 2023 and 2022: Six Months Ended June 30, 2023 2022 Risk free interest rate 3.50 %- 3.56 % 2.80 % Expected volatility 75 %- 76 % 82 % Expected term (years) 6.25 6.25 Expected dividend yield 0 % 0 % Stock-based Compensation Expense Stock-based compensation expense recognized for options and restricted stock units granted was as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2023 2022 2023 2022 Research and development $ 161 $ 105 $ 2,242 $ 216 General and administrative 302 216 9,347 440 Total stock-based compensation expense $ 463 $ 321 $ 11,589 $ 656 The stock-based compensation expense includes one-time charges for the acceleration of vesting of the Graybug stock options at the date of the Merger of $ 1.9 million and $ 8.6 million in research and development and general and administrative expenses, respectively. Common Stock Reserved for Future Issuance Common stock reserved for future issuance consists of the following at June 30, 2023: June 30, 2023 Common stock warrants 276,437 Stock options issued and outstanding 1,739,747 Shares available for issuance under the 2023 Plan 394,309 Shares available under the 2023 ESPP 65,000 Total 2,475,493

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	8. Commitments and Contingencies From time to time, the Company may have certain contingent liabilities that arise in the ordinary course of its business activities. The Company accrues liabilities for such matters when future expenditures are probable and such expenditures can be reasonably estimated. The Company has historically entered into contracts in the normal course of business with contract development and manufacturing organizations, for the manufacturing process development and the preclinical/clinical supply manufacturing, and our vendors for preclinical research studies and other services or products for operating purposes. These contracts generally provide for termination on notice of 60 to 90 days. As of June 30, 2023 , there was one such contract, with approximately $ 1.2 million of associated costs, still in effect for future services, and there were no unpaid cancellation or other related costs. Four lawsuits were filed in federal courts against Graybug and its directors related to the Merger: Bushansky v. Graybug Vision, Inc. , et al., 3:22-cv-09131 (N.D. Cal.), Connelly v. Graybug Vision, Inc., et al. , 3:23-cv-00028 (N.D. Cal.), Plumly v. Graybug Vision, Inc. , et al., 1:23-cv-00169 (D. Del.), and Franchi v. Graybug Vision, Inc. , et al., 1:23-cv-1390 (S.D.N.Y) (collectively, the “Stockholder Litigation”). The complaints named Graybug and its board of directors as defendants. Private CalciMedica and its officers and directors were not named as defendants in the complaints. The complaints asserted claims under Section 14(a) and Section 20(a) of the Exchange Act and Rule 14a-19 promulgated thereunder, and generally allege that the proxy statement misrepresents and/or omits certain purportedly material information relating to the Merger. The complaints sought a variety of equitable and injunctive relief including, among other things, an injunction enjoining the consummation of the merger, rescission of the merger if it is consummated, rescissory damages and costs and attorneys’ fees. During the same period, nine purported stockholders of Graybug sent demand letters regarding the proxy statement (the “Demand Letters”). Based on the same core allegations as the Stockholder Litigation, the Demand Letters requested that Graybug disseminate corrective disclosures in an amendment or supplement to the proxy statement. On March 3, 2023, Graybug filed a Form 8-K to update and supplement the proxy statement with additional disclosures relating to the merger (the “Supplemental Disclosures”). Thereafter, plaintiffs in the Stockholder Litigation voluntarily dismissed their complaints, and opposing counsel (for the stockholders in the Stockholder Litigation and Demand Letters) requested a mootness fee in connection with the Supplemental Disclosures (the “Mootness Fee Demand”). On May 3, 2023, the parties executed a settlement agreement and release resolving the Mootness Fee Demand. The ultimate outcome of any litigation is uncertain and unfavorable outcomes could have a negative impact on the Company’s results of operations and financial condition. Regardless of outcome, litigation can have an adverse impact on the Company due to defense and settlement costs, diversion of management resources, negative publicity and reputational harm, and other factors. We may also, from time to time, become party or subject to various other legal proceedings and claims, either asserted or unasserted, which arise in the ordinary course of business. Some of these proceedings have involved, and may involve in the future, claims that are subject to substantial uncertainties and unascertainable damages. Operating Lease Agreements The Company has an operating lease for office space in La Jolla, California. In January 2023 , an amendment was executed for twelve month term and therefore qualifies for the short-term lease exception. Base rent for this lease is approximately $ 9,000 monthly. As a result of the Merger, the Company leases a facility in Baltimore, Maryland under an operating lease with a term through June 2023 and is accounted for under ASC 842. The facility has been abandoned and the asset was fully impaired in 2022 and was reflected in Graybug’s financial statements in 2022 and there is no impact to the during the six months ended June 30, 2023. The lease expired in June 2023 . Rent expense for the three months ended June 30, 2023 and 2022 was $ 154,000 and $ 65,000 , respectively, and $ 219,000 and $ 130,000 for the six months ended June 30, 2023 and 2022, respectively, which is included in operating expenses. The lease obligation was included in other current liabilities in the condensed consolidated balance sheets.

Employee Benefits

Employee Benefits	6 Months Ended
	Jun. 30, 2023
Retirement Benefits [Abstract]
Employee Benefits	9. Employee Benefits In January 2007, Private CalciMedica adopted a defined contribution 401(k) plan for substantially all employees. Contributions made by Private CalciMedica to the 401(k) plan were immaterial for the three and six months ended June 30, 2023 and 2022 , respectively.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2023
Income Tax Disclosure [Abstract]
Income Taxes	10. Income Taxes The Company did no t record a provision or benefit for income taxes during the three and six months ended June 30, 2023 and 2022. As of both June 30, 2023 and December 31, 2022 , the Company continues to maintain a full valuation allowance against all of its deferred tax assets in light of its history of cumulative net losses.

Net Loss Per Share

Net Loss Per Share	6 Months Ended
	Jun. 30, 2023
Earnings Per Share [Abstract]
Net Loss Per Share	11. Net Loss Per Share The following table sets forth the computation of basic and diluted net loss per share (in thousands, except per share amounts): Three Months Ended June 30, Six Months Ended June 30, 2023 2022 2023 2022 Numerator: Net loss and comprehensive loss $ ( 6,304 ) $ ( 3,030 ) $ ( 25,592 ) $ ( 6,660 ) Denominator Weighted average common stock outstanding, basic and diluted 5,661,933 82,923 3,255,868 80,812 Net loss per share, basic and diluted $ ( 1.11 ) $ ( 36.55 ) $ ( 7.86 ) $ ( 82.42 ) The following outstanding potentially dilutive shares have been excluded from the calculation of diluted net loss per share due to their anti-dilutive effect: As of June 30, 2023 2022 Convertible preferred stock — 2,442,852 Warrants to purchase convertible preferred stock — 328,859 Stock options to purchase common stock 1,739,747 703,437 Warrants to purchase common stock 276,437 11,520 2,016,184 3,486,668

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2023
Subsequent Events [Abstract]
Subsequent Events	12. Subsequent Events The Company has evaluated subsequent events through August 11, 2023, the date on which the accompanying financial statements were issued. During this period, the Company has concluded that no material subsequent events have occurred.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2023
Accounting Policies [Abstract]
Basis of Presentation and Principles of Consolidation	Basis of Presentation and Principles of Consolidation The condensed consolidated financial statements have been prepared in conformity with U.S. generally accepted accounting principles (“U.S. GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification (“ASC”), and Accounting Standards Update (“ASU”), of the Financial Accounting Standards Board (“FASB”). The condensed consolidated financial statements include the accounts of the Company and CalciMedica Subsidiary, Inc. for the three and six months ended June 30, 2023 and 2022. All intercompany accounts and transactions have been eliminated in consolidation. Since Private CalciMedica was determined to be the accounting acquirer in connection with the Merger, for periods prior to the Merger, the condensed consolidated financial statements were prepared on a stand-alone basis for Private CalciMedica and did not include the combined entities activity or financial position. Subsequent to the Merger, the condensed consolidated financial statements as of and for the three and six months ended June 30, 2023 include Graybug’s activity from March 21, 2023 through June 30, 2023 , and assets and liabilities at their acquisition date fair value. Historical share and per share figures of Private CalciMedica have been retroactively restated based on the exchange ratio of 0.0288 .
Use of Estimates	Use of Estimates The preparation of the Company’s condensed consolidated financial statements requires management to make estimates and assumptions that impact the reported amounts of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities in the Company’s condensed consolidated financial statements and accompanying notes. The most significant estimates in the Company’s condensed consolidated financial statements relate to accruals for research and development expenses, valuation of warrants, valuation of convertible promissory notes and valuation of equity awards. These estimates and assumptions are based on current facts, historical experience and various other factors 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 and the recording of expenses that are not readily apparent from other sources. Actual results may differ materially and adversely from these estimates. To the extent there are material differences between the estimates and actual results, the Company’s future results of operations will be affected.
Concentration of Credit Risk and other Risks and Uncertainties	Concentration of Credit Risk and other Risks and Uncertainties Financial instruments, which potentially subject the Company to concentration of risk, consist principally of cash and cash equivalents. The Company’s cash is deposited with major federally insured U.S. financial institutions. The Company has no off-balance sheet concentrations of credit risk, such as foreign currency exchange contracts, option contracts or other hedging arrangements. The Company is dependent on contract manufacturing organizations (“CMO”) to supply products for research and development of its product candidates, including preclinical and clinical studies, and for commercialization of its product candidates, if approved. The Company’s development programs could be adversely affected by any significant interruption in CMO’s operations or by a significant interruption in the supply of active pharmaceutical ingredients and other components. Products developed by the Company require approval from the U.S. Food and Drug Administration (“FDA”) or other international regulatory agencies prior to commercial sales. There can be no assurance the Company’s product candidates will receive the necessary approvals. If the Company is denied approvals, approvals are delayed, or the Company is unable to maintain approvals received, such events could have a materially adverse impact on the Company.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents consist of readily available cash in checking accounts and money market funds. The Company considers all highly liquid investments with an original maturity of three months or less from the date of purchase to be cash equivalents.
Short-term Investments	Short-term Investments The Company invests excess cash in marketable government agency bonds and commercial paper. These investments are included in short-term investments on the balance sheets, classified as available-for-sale and reported at fair value with unrealized gains and losses included in accumulated other comprehensive loss. Realized gains and losses on the sale of these securities are recognized in net loss. As of June 30, 2023, the Company’s short-term investments had converted to cash and cash equivalents.
Segment Information	Segment Information The Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions. The financial information is regularly reviewed by the chief operating decision maker (“CODM”), in deciding how to allocate resources. The Company’s CODM is its chief executive officer. The Company’s singular focus is on developing highly selective calcium release-activated calcium channel inhibitors to improve outcomes for patients with acute inflammatory indications. No significant revenue has been generated since inception, and all tangible assets are held in the United States.
Fair Value Option	Fair Value Option As permitted under ASC 825, Financial Instruments , the Company has elected the fair value option to account for its convertible promissory notes due to certain embedded features within the notes. The Company recognizes the convertible promissory notes at fair value with changes in fair value recognized in the condensed consolidated statements of operations located on the change in fair value of financial instruments line item. Changes in fair value as a result of the Company’s own credit risk is reflected in other income (expense) in the condensed consolidated statements of operations. As a result of applying the fair value option, direct costs and fees related to the convertible promissory notes were expensed as incurred and not deferred.
Property and Equipment	Property and Equipment Property and equipment are recorded at cost and depreciated using the straight-line method over the estimated useful lives of the assets (generally three to five years) and consist of manufacturing and lab equipment, furniture, computers and phones. Repairs and maintenance costs are charged to expense as incurred.
Leases	Leases The Company leases office space with an original lease terms of twelve months . The office lease term has a twelve-month term and does no t have a right-of-use asset or lease liability recorded. The Company's policy is not to record leases with an original term of twelve months or less on the consolidated balance sheets. The Company recognizes lease expense for this short-term lease on a straight-line basis over the term of the lease. The lease is accounted for under ASC 842, Leases , and has been classified as an operating lease. The Company records rent expense on a straight-line basis over the term of the lease.
Long-lived assets	Long-lived Assets Long-lived assets consist primarily of property and equipment. The Company reviews long-lived assets for impairment whenever events or changes in circumstances indicate the carrying amount of an asset is not recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to the future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured as the amount by which the carrying amount of the asset exceeds the fair value of the assets. Fair value would be assessed using discounted cash flows or other appropriate measures of fair value. The Company did not recognize any impairment losses for the three and six months ended June 30, 2023 and 2022 .
Research and Development Costs	Research and Development Costs Research and development costs consist primarily of salaries, payroll taxes, employee benefits and stock-based compensation for those individuals involved in ongoing research and development efforts, as well as fees paid to consultants, external research fees, license fees paid to third parties for use of their intellectual property, laboratory supplies and development of compound materials, associated overhead expenses and facilities and depreciation costs. Nonrefundable advance payments for goods and services that will be used in future research and development activities are expensed when the activity has been performed or when the goods have been received rather than when the payment is made. All research and development costs are expensed as incurred. The Company estimates preclinical studies and clinical trial expenses based on the services performed pursuant to contracts with research institutions and clinical research organizations that conduct and manage preclinical studies and clinical trials on the Company’s behalf. In accruing service fees, the Company estimates the time period over which services will be performed and the level of effort to be expended in each period. These estimates are based on communications with the third-party service providers, the Company’s estimates of accrued expenses and on information available at each balance sheet date. If the actual timing of the performance of services or the level of effort varies from the estimate, the Company will adjust the accrual accordingly. The estimates are trued up to reflect the best information available at the time of the financial statement issuance. Although the Company does not expect its estimates to be materially different from amounts actually incurred, the Company’s estimate of the status and timing of services performed relative to the actual status and timing of services performed may vary.
General and Administrative Costs	General and Administrative Costs General and administrative expenses consist primarily of salaries and related benefits, including stock-based compensation, related to our executive, finance, business development, legal, human resources and support functions, including professional fees for auditing, tax, consulting and patent-related services, rent and utilities and insurance.
Patent Costs	Patent Costs Costs related to filing and pursuing patent applications are expensed as incurred since recoverability of such expenditures is uncertain.
Deferred Offering Costs	Deferred Offering Costs The Company capitalizes costs that are directly associated with equity financings until such financings are consummated at which time such costs are recorded against the gross proceeds of the offering. Should an in-process equity financing be abandoned, the deferred offering costs will be expensed immediately as a charge to operating expenses in the statements of operations and comprehensive loss. Private CalciMedica had deferred offering costs capitalized as of December 31, 2022 for the Merger of $ 1.4 million and $ 1.1 million for a proposed initial public offering (“IPO”) as of December 31, 2021. In September 2022, Private CalciMedica terminated its plan for an IPO and expensed $ 1.5 million to general and administrative expense.
Warrant Liability	Warrant Liability Private CalciMedica has issued various freestanding warrants to purchase shares of its convertible preferred stock. Prior to the Merger, Private CalciMedica adjusted the carrying value of such convertible preferred stock warrants to the estimated fair value at each reporting date, with any related increases or decreases in the fair value being recorded within other income (expense) in the condensed consolidated statements of operations and comprehensive loss. Pursuant to the Merger Agreement, the Series C convertible preferred stock warrants became warrants to purchase shares of the combined company's common stock. As a result of the Merger, the warrants no longer meet the requirements for liability accounting and, as such, Private CalciMedica adjusted the value of the warrants to the estimated fair value as of the Merger date and reclassified them to stockholders' equity (deficit).
Stock-based Compensation	Stock-Based Compensation Stock-based compensation expense represents the cost of the grant date fair value of employee stock options recognized over the requisite service period of the awards (usually the vesting period) on a straight-line basis. Private CalciMedica estimates the fair value of stock option grants using the Black-Scholes option pricing model (“Black-Scholes”). Forfeitures are recognized as a reduction of stock-based compensation expense as they occur. Equity-based compensation expense is classified in the statements of operations in the same manner in which the award recipients’ payroll costs are classified or in which the award recipients’ service payments are classified. The fair value of each stock option grant is estimated on the date of grant using Black Scholes. The following summarizes the inputs used: Fair Value of Common Stock Prior to the Merger, there was no public market for Private CalciMedica’s common stock. The fair value of the shares of common stock underlying Private CalciMedica ’s share-based awards was estimated on each grant date by Private CalciMedica’s board of directors. To determine the fair value of Private CalciMedica’s common stock underlying option grants, the board of directors considered, among other things, input from management and valuations of Private CalciMedica's common stock prepared by third-party valuation firms. Post Merger, CalciMedica will use the closing stock price the day prior to the grant date for the fair value. Risk-Free Interest Rate The risk-free interest ra te is based on the U.S. Treasury yield in effect at the time of grant for zero coupon U.S. Treasury notes with maturities similar to the expected term of the awards. Expected Volatility Since Private CalciMedica did not have publicly traded equity securities, the volatility of the options has been estimated using peer group volatility information. Post Merger, CalciMedica will use an average volatility for comparable publicly-traded biopharmaceutical companies over a period equal to the expected term of the stock award grant as CalciMedica does not yet have sufficient historical trading history for its own stock. CalciMedica will continue to apply this method until a sufficient amount of historical information over a period equal to the expected term of the stock-based awards becomes available. Expected Term CalciMedica used the simplified method to calc ulate the expected term for all grants during all periods, which is based on the midpoint between the vesting date and the end of the contractual term. Expected Dividend Yield CalciMedica has never paid and has no present intention to pay cash dividends.
Income Taxes	Income Taxes The Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, deferred tax assets and liabilities are determined on the basis of the differences between the financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. The Company recognizes net deferred tax assets to the extent that the Company believes these assets are more likely than not to be realized. In making such a determination, management considers all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning strategies, and results of recent operations. If management determines that the Company would be able to realize its deferred tax assets in the future in excess of their net recorded amount, management would make an adjustment to the deferred tax asset valuation allowance, which would reduce the provision for income taxes. The Company records uncertain tax positions on the basis of a two-step process whereby (1) management determines whether it is more likely than not that the tax positions will be sustained on the basis of the technical merits of the position and (2) for those tax positions that meet the more-likely-than-not recognition threshold, management recognizes the largest amount of tax benefit that is more than 50 % likely to be realized upon ultimate settlement with the related tax authority. The Company recognizes interest and penalties related to unrecognized tax benefits within income tax expense. Any accrued interest and penalties are included within the related tax liability.
Comprehensive Loss	Comprehensive Loss Comprehensive loss is defined as a change in equity during a period from transactions and other events and circumstances from non-owner sources. The Company’s comprehensive loss was the same as its reported net loss for all periods presented.
Related party transactions	Related Party Transactions The Company’s board of directors reviews and approves transactions with directors, officers and holders of 5 % or more of its voting securities and their affiliates, each a related party. The material facts as to the related party’s relationship or interest in the transaction are disclosed to its board of directors prior to their consideration of such transaction, and the transaction is not considered approved by its board of directors unless a majority of the directors who are not interested in the transaction approve the transaction. Beginning in November 2020, Private CalciMedica has paid consulting fees monthly to a consulting firm affiliated with the Company’s interim chief financial officer in connection with its consulting agreement. Private CalciMedica recorded expense of $ 227,000 a nd $ 58,000 during the three months ended June 30, 2023 and 2022 , respectively, and $ 346,000 and $ 100,000 during the six months ended June 30, 2023 and 2022 , respectively.
Net Loss Per Share	Net Loss Per Share Net loss is equivalent to net loss attributable to common stockholders for all periods presented. Basic net loss per share is computed using the weighted average number of shares of common stock outstanding during the period. The Company calculates diluted net loss per share using the more dilutive of the (1) treasury stock method, if-converted method, or contingently issuable share method, as applicable, or (2) the two-class method. For warrants, the calculation of diluted net loss per share requires that, to the extent the average fair value of the underlying shares for the reporting period exceeds the exercise price of the warrants and the presumed exercise of such securities are dilutive to net loss per share for the period, adjustments to net loss used in the calculation are required to remove the change in fair value of the warrants for the period. In all periods presented, the Company’s outstanding preferred stock, stock options, preferred, common and convertible promissory note warrants, and outstanding convertible promissory notes were excluded from the calculation of loss per share because the effect would be antidilutive. Accordingly, in periods in which the Company reports a net loss, diluted net loss per share is the same as basic net loss per share.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments , which changes the accounting for recognizing impairments of financial assets. Under the new guidance, credit losses for certain types of financial instruments will be estimated based on expected losses. The new guidance also modifies the impairment models for available-for-sale debt securities and for purchased financial assets with credit deterioration since their origination. This update is effective for the Company beginning January 1, 2023. The Company adopted this ASU as of January 1, 2023, which did not have an impact on its condensed consolidated financial statements and related disclosures. In August 2020, the FASB issued ASU 2020-06, Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40) . The ASU provides guidance that simplified the accounting for certain financial instruments with characteristics of liabilities and equity. The new guidance reduced the number of accounting models for convertible debt and convertible preferred stock instruments and made certain disclosure amendments intended to improve the information provided to users. The guidance also amended the derivative guidance for the “own stock” scope exception, which exempts qualifying instruments from being accounted for as derivatives if certain criteria are met. Finally, the standard changed the way certain convertible instruments are treated when calculating earnings per share. This guidance is effective for fiscal years beginning after December 15, 2023, including interim periods within those fiscal years, with early adoption permitted. The Company is currently assessing the impact that this guidance will have on its condensed consolidated financial statements.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2023
Fair Value Disclosures [Abstract]
Schedule of Assets Measured at Fair Value on Recurring Basis	The following tables present information about the Company’s financial assets measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): June 30, 2023 Level 1 Level 2 Level 3 Total Current assets: Cash equivalents: Money market funds $ 18,699 $ — $ — $ 18,699 Total cash equivalents 18,699 — — 18,699 Total assets measured at fair value $ 18,699 $ — $ — $ 18,699 December 31, 2022 Level 1 Level 2 Level 3 Total Liabilities: Convertible promissory notes $ — $ — $ 5,157 $ 5,157 Preferred Warrants liability — — 1,453 1,453 Convertible Promissory Note Warrants liability — — 1,192 1,192 Total liabilities measured at fair value $ — $ — $ 7,802 $ 7,802
Reconciliation of Liabilities Measured at Fair Value Using Level 3 Inputs	The following provides a reconciliation for all liabilities measured at fair value using Level 3 inputs for the six months ended June 30, 2023 (in thousands): Convertible Promissory Note liability Balance at December 31, 2022 $ 5,157 Change in Fair Value of Convertible Promissory Notes ( 2,022 ) Accrued Interest 110 Conversion of Convertible Promissory Notes to equity ( 3,245 ) Balance at June 30, 2023 $ — Preferred Warrant liability Balance at December 31, 2022 $ 1,453 Change in Fair Value of Preferred Warrants ( 795 ) Conversion of warrant liability to equity ( 658 ) Balance at Jane 30, 2023 $ — Convertible Promissory Note Warrants liability Balance at December 31, 2022 $ 1,192 Change in Fair Value of Convertible Promissory Note Warrants ( 351 ) Conversion of Convertible Promissory Note Warrants liability to equity ( 841 ) Balance at June 30, 2023 $ —

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2023
Share-Based Payment Arrangement [Abstract]
Summary of Stock Option Transations	The following table summarizes the stock option transactions for the 2006 and 2023 Plan: Total Options Weighted Average Exercise Price Weighted Average Remaining Contractual Term (years) Aggregate Intrinsic Value (in thousands) Outstanding at December 31, 2022 739,511 $ 6.94 7.36 $ 8,903 Assumed in the Merger 310,431 76.72 Granted 785,922 6.48 Forfeited ( 96,117 ) 70.79 Outstanding at June 30, 2023 1,739,747 $ 15.71 7.50 $ 624 Vested and exercisable at June 30, 2023 811,701 $ 6.01 6.70 $ 231
Schedule of Assumptions Using Black-Scholes to Estimate Fair Value of the stock option grants	The following is the range of underlying assumptions in Black-Scholes to determine the fair value of the stock option grants for the six months ended June 30, 2023 and 2022: Six Months Ended June 30, 2023 2022 Risk free interest rate 3.50 %- 3.56 % 2.80 % Expected volatility 75 %- 76 % 82 % Expected term (years) 6.25 6.25 Expected dividend yield 0 % 0 %
Summary of Stock-Based Compensation Expense Recognized for Options and RSUs Granted	Stock-based compensation expense recognized for options and restricted stock units granted was as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2023 2022 2023 2022 Research and development $ 161 $ 105 $ 2,242 $ 216 General and administrative 302 216 9,347 440 Total stock-based compensation expense $ 463 $ 321 $ 11,589 $ 656 The stock-based compensation expense includes one-time charges for the acceleration of vesting of the Graybug stock options at the date of the Merger of $ 1.9 million and $ 8.6 million in research and development and general and administrative expenses, respectively.
Schedule of Common Stock Reserved for Future issuance	Common stock reserved for future issuance consists of the following at June 30, 2023: June 30, 2023 Common stock warrants 276,437 Stock options issued and outstanding 1,739,747 Shares available for issuance under the 2023 Plan 394,309 Shares available under the 2023 ESPP 65,000 Total 2,475,493

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	6 Months Ended
	Jun. 30, 2023
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Net Loss Per Share	The following table sets forth the computation of basic and diluted net loss per share (in thousands, except per share amounts): Three Months Ended June 30, Six Months Ended June 30, 2023 2022 2023 2022 Numerator: Net loss and comprehensive loss $ ( 6,304 ) $ ( 3,030 ) $ ( 25,592 ) $ ( 6,660 ) Denominator Weighted average common stock outstanding, basic and diluted 5,661,933 82,923 3,255,868 80,812 Net loss per share, basic and diluted $ ( 1.11 ) $ ( 36.55 ) $ ( 7.86 ) $ ( 82.42 )
Schedule of Anti-dilutive Securities Excluded from Calculation of Diluted Net Loss Per Share	The following outstanding potentially dilutive shares have been excluded from the calculation of diluted net loss per share due to their anti-dilutive effect: As of June 30, 2023 2022 Convertible preferred stock — 2,442,852 Warrants to purchase convertible preferred stock — 328,859 Stock options to purchase common stock 1,739,747 703,437 Warrants to purchase common stock 276,437 11,520 2,016,184 3,486,668

Nature of Business - Additional

Nature of Business - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended					6 Months Ended
		Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	[1]	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Net loss		$ (6,304)	$ (19,288)	$ (3,030)	$ (3,630)		$ (25,592)	$ (6,660)
Accumulated deficit	[2]	(137,299)					(137,299)		$ (111,707)
Acceleration of stock awards							10,500
Severance and termination benefit expense							5,700
Consideration Transferred							29,400
Total operating expenses		6,583		$ 3,589			28,923	$ 7,800
Cash and cash equivalents		$ 19,084					$ 19,084		$ 1,327
CalciMedica
Percentage of ownership of common stock		72%					72%
Graybug
Severance and termination benefit expense							$ 16,200
Percentage of ownership of common stock		28%					28%
Convertible Debt [Member]
Proceeds from issuance of convertible notes							$ 8,600
Preferred and Common stock [Member]
Total Gross Proceeds							$ 111,700
[1] (1) Retroactively restated for the reverse recapitalization as described in Note 2. (1) Retroactively restated for the reverse recapitalization as described in Note 2.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Details)	1 Months Ended	3 Months Ended		6 Months Ended
	Sep. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Stockholders equity note stock split exchange ratio				0.0288
Lease term		12 months		12 months
Right-of-use asset or lease liability		$ 0		$ 0
General and administrative		2,769,000	$ 1,330,000	$ 18,618,000	$ 2,616,000
Tax postion, Minimum percentage of tax benefit				50%
Variable interest entity ownership percentage				5%
Private CalciMedica
Summary Of Significant Accounting Policies [Line Items]
Deferred Offering Costs						$ 1,400,000
Costs and expenses related party		$ 227,000	$ 58,000	$ 346,000	$ 100,000
IPO [Member] | Private CalciMedica
Summary Of Significant Accounting Policies [Line Items]
Deferred Offering Costs							$ 1,100,000
General and administrative	$ 1,500,000

Merger and Related Transactio_2

Merger and Related Transactions - Additional Information (Details) $ / shares in Units, $ in Millions		6 Months Ended
	Mar. 17, 2023 $ / shares	Jun. 30, 2023 USD ($) $ / shares shares	Mar. 31, 2023 $ / shares	Dec. 31, 2022 $ / shares
Business Acquisition [Line Items]
Number of shares of stock issued | shares		310,431
Stock issued during period private placement | shares		0.0288
Consideration Transferred		$ 29.4
Prepaid and other current assets obtained		2.1
Payables and accruals incurred		2.3
Transaction costs		$ 4.6
Common stock par value | $ / shares		$ 0.0001		$ 0.0001
Severance and termination benefit expense		$ 5.7
Acceleration of stock awards		$ 10.5
Common Stock
Business Acquisition [Line Items]
Shares issued during period upon conversion of units | shares		3,946,540
CalciMedica
Business Acquisition [Line Items]
Percentage of ownership of common stock		72%
Graybug
Business Acquisition [Line Items]
Percentage of ownership of common stock		28%
Severance and termination benefit expense		$ 16.2
Graybug
Business Acquisition [Line Items]
Number of shares of stock issued | shares		1,571,433
Common stock par value | $ / shares	$ 0.0001		$ 0.0001
Reverse Stock Split	14
Acceleration of stock awards		$ 10.5

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Assets Measured at Fair Value on Recurring Basis (Details) - USD ($)	Jun. 30, 2023	Dec. 31, 2022
Liabilities:
Total liabilities measured at fair value	$ 0
Fair Value, Recurring
Current assets:
Cash equivalents	18,699,000
Assets measured at fair value	18,699,000
Liabilities:
Total liabilities measured at fair value		$ 7,802,000
Fair Value, Recurring | Money Market Funds
Current assets:
Cash equivalents	18,699,000
Fair Value, Recurring | Convertible promissory notes
Liabilities:
Total liabilities measured at fair value		5,157,000
Fair Value, Recurring | Preferred warrants liability
Liabilities:
Total liabilities measured at fair value		1,453,000
Fair Value, Recurring | Convertible Promissory Note Warrants Liability [Member]
Liabilities:
Total liabilities measured at fair value		1,192,000
Fair Value, Recurring | Level 1
Current assets:
Cash equivalents	18,699,000
Assets measured at fair value	18,699,000
Fair Value, Recurring | Level 1 | Money Market Funds
Current assets:
Cash equivalents	$ 18,699,000
Fair Value, Recurring | Level 3
Liabilities:
Total liabilities measured at fair value		7,802,000
Fair Value, Recurring | Level 3 | Convertible promissory notes
Liabilities:
Total liabilities measured at fair value		5,157,000
Fair Value, Recurring | Level 3 | Preferred warrants liability
Liabilities:
Total liabilities measured at fair value		1,453,000
Fair Value, Recurring | Level 3 | Convertible Promissory Note Warrants Liability [Member]
Liabilities:
Total liabilities measured at fair value		$ 1,192,000

Fair Value Measurements - Recon

Fair Value Measurements - Reconciliation of Liabilities Measured at Fair Value Using Level 3 Inputs (Details) - Fair Value, Recurring - Fair Value, Inputs, Level 3 [Member] $ in Thousands	6 Months Ended
	Jun. 30, 2023 USD ($)
Preferred Warrants [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at June 30, 2023	$ 0
Preferred Warrant [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at December 31, 2022	1,453
Change in Fair Value	(795)
Conversion	(658)
Balance at June 30, 2023	0
Convertible Promissory Note Warrants [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at December 31, 2022	1,192
Change in Fair Value	(351)
Conversion	(841)
Convertible Promissory Note [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at December 31, 2022	5,157
Change in Fair Value	(2,022)
Accrued Interest	110
Conversion	(3,245)
Balance at June 30, 2023	$ 0

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($)	Jun. 30, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents		$ 0
Fair value liabilities	$ 0
Fair Value, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value liabilities		$ 7,802,000

Convertible Promissory Notes _2

Convertible Promissory Notes and Convertible Promissory Note Warrants - Additional Information (Details) - USD ($)	1 Months Ended		6 Months Ended
	Nov. 30, 2022	Apr. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Mar. 20, 2023	Nov. 20, 2022
Debt Instrument [Line Items]
Public combination multiplied cash price paid per share	$ 0.85
Percentage of warrant coverage	40%
Risk free interest rate				2.80%
Expected volatility				82%
Expected term (years)			6 years 3 months	6 years 3 months
Minimum
Debt Instrument [Line Items]
Risk free interest rate			3.50%
Expected volatility			75%
Maximum
Debt Instrument [Line Items]
Risk free interest rate			3.56%
Expected volatility			76%
Common Stock
Debt Instrument [Line Items]
Percentage of warrant coverage						15%
Common Stock | Private CalciMedica
Debt Instrument [Line Items]
Number of convertible promissory note converted into common stock	20,487,104
Common Stock | Graybug
Debt Instrument [Line Items]
Number of convertible promissory note converted into common stock	590,031
Convertible promissory notes
Debt Instrument [Line Items]
Issuance or Sale of Convertible Promissory Notes		$ 5,000,000
Gross proceeds of Convertible Promissory Notes	$ 5	$ 3,500,000
Debt Instrument, Interest Rate During Period	6%
Convertible promissory notes | Common Stock
Debt Instrument [Line Items]
Exercise price of warrants per share		$ 0.01
Convertible Promissory Note Warrants
Debt Instrument [Line Items]
Issuance or Sale of Convertible Promissory Notes	$ 8,500,000
Exercise price of warrants per share	$ 0.01
Addiitional convertible promissory notes and Convertible Promissory Note Warrants	$ 3,500,000
Convertible promissory note warrants convertible	5,308,047
Convertible promissory note warrants common stock converted	5,308,047				152,871
Exchange of stock for stock	152,875
Expected Per Share					$ 5.5
Convertible Promissory Note Warrants | Minimum
Debt Instrument [Line Items]
Risk free interest rate	3.02%
Expected volatility	63%
Expected term (years)	4 years 1 month 6 days
Convertible Promissory Note Warrants | Maximum
Debt Instrument [Line Items]
Risk free interest rate	4.20%
Expected volatility	67%
Expected term (years)	4 years 7 months 6 days
Convertible Promissory Note Warrants | Common Stock
Debt Instrument [Line Items]
Exercise price of warrants per share	$ 0.01

Convertible Preferred Stock, _2

Convertible Preferred Stock, Common Stock and Stockholders' Deficit - Additional Information (Details) - USD ($)		1 Months Ended						3 Months Ended			6 Months Ended		12 Months Ended
	Mar. 20, 2023	Oct. 31, 2022	Jul. 31, 2021	Jun. 30, 2021	Mar. 31, 2021	Feb. 28, 2021	Nov. 30, 2020	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	Mar. 17, 2023
Temporary Equity [Line Items]
Common stock, shares authorized								500,000,000			500,000,000		5,694,626
Preferred stock, shares authorized								10,000,000			10,000,000		0
Common stock, shares issued								5,661,933			5,661,933		84,165
Fair value of warrant liability											$ (1,146,000)	$ (1,169,000)
Common stock par value								$ 0.0001			$ 0.0001		$ 0.0001
Fair value of warrants								$ 796,000		$ 1,200,000	$ 796,000	$ 1,200,000
Expected term (years)											6 years 3 months	6 years 3 months
Risk free interest rate												2.80%
Expected volatility												82%
Expected dividend yield											0%	0%
General and administrative								$ 2,769,000		1,330,000	$ 18,618,000	$ 2,616,000
Preferred stock, par value								$ 0.0001			$ 0.0001		$ 0.0001
Private Placement
Temporary Equity [Line Items]
Stock issued											20,700,000
Proceeds from private placement											$ 10,300,000
Amended and Restated Certificate of Incorporation
Temporary Equity [Line Items]
Common stock, shares authorized								500,000,000			500,000,000
Preferred stock, shares authorized								10,000,000			10,000,000
Common stock par value								$ 0.0001			$ 0.0001
Preferred stock, par value								$ 0.0001			$ 0.0001
Chief Financial Officer
Temporary Equity [Line Items]
Exercise price of warrants per share							$ 0.19
Stock and warrants issued during period shares common stock and warrants							400,000
Warrant liability fair value							$ 120,000
Expected term (years)							10 years
Risk free interest rate							0.96%
Expected volatility							80%
Expected dividend yield							0%
General and administrative								$ 13,000		15,000	$ 25,000	30,000
Vesting period							24 months
Warrant term							10 years
Officers and Directors
Temporary Equity [Line Items]
Exercise price of warrants per share		$ 10.42
Stock and warrants issued during period shares common stock and warrants		496,970
Warrant liability fair value		$ 125,000
Expected term (years)		10 years
Risk free interest rate		4.10%
Expected volatility		82%
Expected dividend yield		0%
General and administrative								14,000			$ 28,000
Warrant term		10 years
Graybug
Temporary Equity [Line Items]
Common stock par value									$ 0.0001					$ 0.0001
Maximum
Temporary Equity [Line Items]
Risk free interest rate											3.56%
Expected volatility											76%
Maximum | Officers and Directors
Temporary Equity [Line Items]
Vesting period		48 months
Minimum
Temporary Equity [Line Items]
Risk free interest rate											3.50%
Expected volatility											75%
Minimum | Officers and Directors
Temporary Equity [Line Items]
Vesting period		12 months
Common Stock
Temporary Equity [Line Items]
Common stock, shares issued	1,571,433
Conversion of preferred stock to common stock as a result of the Merger, shares									2,442,852
Preferred Stock
Temporary Equity [Line Items]
Fair value of warrants								$ 0		$ 588,000	$ 0	$ 588,000
Series C-2 Preferred
Temporary Equity [Line Items]
Exercise price of warrants per share								$ 0.77			$ 0.77
Series C-2 Preferred | IPO [Member]
Temporary Equity [Line Items]
Stock issued											2,786,567
Series D Convertible Preferred Stock
Temporary Equity [Line Items]
Preferred stock, shares authorized								0			0		88,875,077
Convertible preferred stock, shares issued			745,804	12,911,742	5,069,660
Convertible preferred stock, price per share			$ 0.8045	$ 0.8045	$ 0.8045	$ 0.8045
Gross proceeds from issue of convertible preferred stock			$ 600,000	$ 10,400,000	$ 4,100,000	$ 6,600,000
Preferred stock, par value								$ 0.001			$ 0.001		$ 0.001
Series D Convertible Preferred Stock | Maximum
Temporary Equity [Line Items]
Convertible preferred stock, shares issued						8,152,834
Calcimedica Preferred Stock
Temporary Equity [Line Items]
Conversion of stock, shares converted	84,820,880
Calcimedica Common Stock
Temporary Equity [Line Items]
Conversion of preferred stock to common stock as a result of the Merger, shares	2,442,852
Series B Warrants
Temporary Equity [Line Items]
Exercise price of warrants per share								$ 0.77			$ 0.77
Warrants issued											568,181
Fair value of warrant liability											$ 21,000
Warrant liability fair value													$ 45,000
Warrant term								10 years			10 years
Series C-2 Warrants
Temporary Equity [Line Items]
Number of warrants converted to common stock								80,254			80,254
Fair value of warrant liability											$ 400,000		900,000
Warrants exercisable											2,786,567
Warrant term								10 years			10 years
Series D Warrants
Temporary Equity [Line Items]
Exercise price of warrants per share						$ 0.8045		$ 0.8045			$ 0.8045
Warrants issued											8,063,998
Fair value of warrant liability													$ 600,000
Fair value of warrants						$ 1,800,000
Warrant term								5 years			5 years
Pre Merger CalciMedica | Private Placement
Temporary Equity [Line Items]
Conversion of stock, shares converted	20,706,997
Post Merger CalciMedica | Private Placement
Temporary Equity [Line Items]
Conversion of Stock, Shares Issued	596,363
Prior to Merger Transaction | Series B Warrants
Temporary Equity [Line Items]
Number of warrants converted to common stock								568,181			568,181
Prior to Merger Transaction | Series D Warrants
Temporary Equity [Line Items]
Number of warrants converted to common stock								8,063,998			8,063,998
Post Merger Transaction | Chief Financial Officer
Temporary Equity [Line Items]
Exercise price of warrants per share								$ 6.6			$ 6.6
Number of warrants converted to common stock							11,520
Post Merger Transaction | Officers and Directors
Temporary Equity [Line Items]
Exercise price of warrants per share		$ 10.42
Number of warrants converted to common stock		14,313
Post Merger Transaction | Series B Warrants
Temporary Equity [Line Items]
Exercise price of warrants per share								$ 26.74			$ 26.74
Number of warrants converted to common stock								16,366			16,366
Post Merger Transaction | Series D Warrants
Temporary Equity [Line Items]
Exercise price of warrants per share								$ 27.94			$ 27.94
Number of warrants converted to common stock								232,256			232,256
Fair value of warrant liability											$ 200,000

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Mar. 20, 2023	Dec. 31, 2022	Dec. 06, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares reserved for future issuance	2,475,493		2,475,493
Number of options, granted			785,922
Weighted average exercise price, granted			$ 6.48
Common stock, shares issued	5,661,933		5,661,933			84,165
Stock-based compensation expense	$ 463	$ 321	$ 11,589	$ 656
Acceleration of stock awards			10,500
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	161	105	2,242	216
General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 302	$ 216	9,347	$ 440
Graybug
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Acceleration of stock awards			10,500
Graybug | Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			1,900
Graybug | General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			$ 8,600
2006 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period			10 years
Award vesting rights, percentage			25%
Award vesting period			1 year
Vesting period			36 months
Amendment to 2006 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares reserved for future issuance							180,245
2023 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares reserved for future issuance	394,309		394,309		1,000,000
Percentage of aggregate number of shares of common stock outstanding on last day of preceding year added to plan			5%
Shares available for grant (shares)	394,309		394,309
2023 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares reserved for future issuance	65,000		65,000
Weighted averagefair value options, granted			$ 4.47	$ 14.24
Total fair value of shares vested			$ 11,600	$ 500
Common stock, shares issued	195,000		195,000
Stock issued on exercise of stock options, Shares			0
Percentage of aggregate number of shares of common stock outstanding on last day of preceding year added to plan			1%
Stock Issued			0
Total unrecognized stock-based compensation expenses related to outstanding unvested stock awards	$ 4,400		$ 4,400
Total unrecognized stock-based compensation expenses related to outstanding unvested stock awards weighted-average term of recognition			2 years 10 months 24 days

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Share-Based Payment Arrangement [Abstract]
Number of options, outstanding	739,511
Number of options, Assumed in the Merger	310,431
Number of options, granted	785,922
Number of options, forfeited	(96,117)
Number of options, outstanding	1,739,747	739,511
Number of options, vested and exercisable	811,701
Weighted average exercise price, outstanding	$ 6.94
Weighted Average Exercise Price, Assumed in the Merger	76.72
Weighted average exercise price, granted	6.48
Weighted average exercise price, forfeited	70.79
Weighted average exercise price, outstanding	15.71	$ 6.94
Weighted average exercise price, options vested and exercisable	$ 6.01
Weighted average remaining contractual term, outstanding	7 years 6 months	7 years 4 months 9 days
Weighted average remaining contractual term, options vested and exercisable	6 years 8 months 12 days
Aggregate intrinsic value, outstanding	$ 624	$ 8,903
Agrgregate intrinsic value, vested and exercisable	$ 231

Stock Based Compensation - Sche

Stock Based Compensation - Schedule of Assumptions Using Black- Scholes to Estimated Fair value of Each Awards (Details)	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk free interest rate		2.80%
Expected volatility		82%
Expected term (years)	6 years 3 months	6 years 3 months
Expected dividend yield	0%	0%
Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk free interest rate	3.56%
Expected volatility	76%
Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk free interest rate	3.50%
Expected volatility	75%

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Stock-Based Compensation Expense Recognized for Options and RSUs Granted (Details) - 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]
Total stock-based compensation expense	$ 463	$ 321	$ 11,589	$ 656
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	161	105	2,242	216
General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	$ 302	$ 216	$ 9,347	$ 440

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Common Stock Reserved for Future issuance (Details) - shares	Jun. 30, 2023	Mar. 20, 2023	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common stock warrants	276,437
Stock options issued and outstanding	1,739,747		739,511
Common stock shares reserved for future issuance	2,475,493
2023 Equity Incentive Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common stock shares reserved for future issuance	394,309	1,000,000
2023 Employee Stock Purchase Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common stock shares reserved for future issuance	65,000

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2023 USD ($) Contract	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) Contract	Jun. 30, 2022 USD ($)
Loss Contingencies [Line Items]
Rent expense	$ 154,000	$ 65,000	$ 219,000	$ 130,000
Lease Amendment Date			2023-01
Number of contract currently in effect | Contract	1		1
Contractual obligation of contract in effect	$ 1,200,000		$ 1,200,000
Unpaid cancellation and other related costs			0
Base rent			$ 9,000
Short term operating lease expiration date			Jun. 30, 2023
Baltimore, Maryland
Loss Contingencies [Line Items]
Operating lease, term			2023-06

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Income Tax Disclosure [Abstract]
Provision or benefit for income taxes	$ 0	$ 0	$ 0	$ 0

Net Loss Per Share - Schedule o

Net Loss Per Share - Schedule of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended					6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	[1]	Jun. 30, 2023	Jun. 30, 2022
Earnings Per Share [Abstract]
Net loss and comprehensive loss	$ (6,304)	$ (19,288)	$ (3,030)	$ (3,630)		$ (25,592)	$ (6,660)
Weighted average common stock outstanding, basic	5,661,933		82,923			3,255,868	80,812
Weighted average common stock outstanding, diluted	5,661,933		82,923			3,255,868	80,812
Net loss per share—basic	$ (1.11)		$ (36.55)			$ (7.86)	$ (82.42)
Net loss per share—diluted	$ (1.11)		$ (36.55)			$ (7.86)	$ (82.42)
[1] (1) Retroactively restated for the reverse recapitalization as described in Note 2.

Net Loss Per Share - Schedule_2

Net Loss Per Share - Schedule of Anti-dilutive Securities Excluded from Calculation of Diluted Net Loss Per Share (Details) - shares	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from calculation of diluted net loss per share	2,016,184	3,486,668
Convertible Preferred Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from calculation of diluted net loss per share	0	2,442,852
Warrants to Purchase Convertible Preferred Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from calculation of diluted net loss per share	0	328,859
Stock Options to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from calculation of diluted net loss per share	1,739,747	703,437
Warrants to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from calculation of diluted net loss per share	276,437	11,520