Cue Biopharma (CUE) 10-Q 8 May 19 2019 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2019	May 01, 2019
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Trading Symbol	CUE
Entity Registrant Name	Cue Biopharma, Inc.
Entity Central Index Key	0001645460
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Common Stock, Shares Outstanding		20,783,246

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 21,913,000	$ 20,800,000
Marketable securities, short term	8,966,000	18,413,000
Restricted cash, short-term	50,000	50,000
Prepaid expenses and other current assets	1,039,000	1,347,000
Total current assets	31,968,000	40,610,000
Property and equipment, net	2,595,000	2,781,000
Operating lease right-of-use	8,691,000
Deposits	1,013,000	1,013,000
Restricted cash, long term	150,000	150,000
Other long term assets	771,000	809,000
Total assets	45,188,000	45,363,000
Current liabilities:
Accounts payable	2,893,000	2,035,000
Accrued expenses	2,149,000	1,788,000
Research and development contract liability, current portion	1,887,000	2,012,000
Deferred rent		381,000
Operating lease liability, current portion	3,644,000
Total current liabilities	10,573,000	6,216,000
Research and development contract liability, net of current portion	4,930,000	5,175,000
Operating lease liability, net of current portion	4,947,000
Total liabilities	20,450,000	11,391,000
Stockholders’ equity:
Preferred Stock, $0.001 par value; 10,000,000 shares authorized and 0 shares issued and outstanding at March 31, 2019 and December 31, 2018
Common stock, $0.001 par value; 50,000,000 shares authorized; 20,783,246 and 20,697,453 shares issued and outstanding, at March 31, 2019 and December 31, 2018, respectively	21,000	21,000
Additional paid in capital	107,788,000	105,763,000
Accumulated other comprehensive loss	(3,000)	(11,000)
Accumulated deficit	(83,068,000)	(71,801,000)
Total stockholders’ equity	24,738,000	33,972,000
Total liabilities and stockholders’ equity	$ 45,188,000	$ 45,363,000

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) (Unaudited) - $ / shares	Mar. 31, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	20,783,246	20,697,453
Common stock, shares outstanding	20,783,246	20,697,453

Consolidated Statements of Oper

Consolidated Statements of Operations and Other Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Collaboration revenue	$ 370
Operating expenses:
General and administrative	3,444	$ 1,703
Research and development	8,353	5,819
Total operating expenses	11,797	7,522
Loss from operations	(11,427)	(7,522)
Other income (expense):
Interest income	114
Other income (expense), net	46	(1)
Total other income (expense)	160	(1)
Net loss	(11,267)	(7,523)
Unrealized gains (losses) from available-for-sale securities, net of tax of $0	(3)
Comprehensive loss	$ (11,270)	$ (7,523)
Net loss per common share – basic and diluted	$ (0.54)	$ (0.37)
Weighted average common shares outstanding – basic and diluted	20,718,233	20,063,609

Consolidated Statements of Op_2

Consolidated Statements of Operations and Other Comprehensive Loss (Parenthetical) (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Unrealized gains (losses) from available-for-sale securities. tax	$ 0	$ 0

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Common Stock To Be Issued	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Balance at Dec. 31, 2017	$ 61,607	$ 19	$ 1	$ 94,408		$ (32,821)
Balance, Shares at Dec. 31, 2017		19,459,194	671,572
Stock-based compensation	1,158			1,158
License agreements		$ 1	$ (1)
License agreements, Shares		671,572	(671,572)
Net loss	(7,523)					(7,523)
Balance at Mar. 31, 2018	55,242	$ 20		95,566		(40,344)
Balance, Shares at Mar. 31, 2018		20,130,766
Balance at Dec. 31, 2018	33,972	$ 21		105,763	$ (11)	(71,801)
Balance, Shares at Dec. 31, 2018		20,697,453
Stock-based compensation	1,768			1,768
Exercise of stock options	$ 257			257
Exercise of stock options, Shares	85,793	85,793
Other comprehensive income (loss)	$ 8				8
Net loss	(11,267)					(11,267)
Balance at Mar. 31, 2019	$ 24,738	$ 21		$ 107,788	$ (3)	$ (83,068)
Balance, Shares at Mar. 31, 2019		20,783,246

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities
Net loss	$ (11,267,000)	$ (7,523,000)
Adjustments to reconcile net loss to cash used in operating activities:
Depreciation	205,000	167,000
Stock-based compensation	1,768,000	1,158,000
Deferred rent		(27,000)
Operating lease right of use amortization	1,001,000
Operating lease liability	(756,000)
Other non cash charges	(5,000)
Non-cash investment expense	(45,000)
Changes in operating assets and liabilities:
Research and development contract advances		(531,000)
Prepaid expenses and other current assets	(225,000)	(481,000)
Deposits		(1,060,000)
Accounts payable	858,000	(391,000)
Accrued expenses	361,000	(599,000)
Research and development contract liability	(370,000)	(472,000)
Net cash used in operating activities	(8,475,000)	(9,759,000)
Cash flows from investing activities
Purchases of property and equipment	(19,000)	(673,000)
Redemption of short term investments	9,500,000
Net cash provided by (used in) investing activities	9,481,000	(673,000)
Cash flows from financing activities
Proceeds from exercise of stock options	257,000
Net cash provided by financing activities	257,000
Net increase/(decrease) in cash, cash equivalents, and restricted cash	1,263,000	(10,432,000)
Cash, cash equivalents, and restricted cash at beginning of period	20,850,000	63,534,000
Cash, cash equivalents, and restricted cash at end of period	$ 22,113,000	53,102,000
Non-cash investing and financing activities:
Purchases of property and equipment in accounts payable or accrued expenses		$ 227,000

Organization and Basis of Prese

Organization and Basis of Presentation	3 Months Ended
	Mar. 31, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization and Basis of Presentation	1. Cue Biopharma, Inc. (the “Company”) was incorporated in the State of Delaware on December 31, 2014 under the name Imagen Biopharma, Inc., and completed its organization, formation, and initial capitalization activities effective as of January 1, 2015. In October 2016, the Company changed its name to Cue Biopharma, Inc. The Company’s corporate office and research facilities are located in Cambridge, Massachusetts. The Company is in the development stage and has incurred recurring losses and negative cash flows from operations. As of March 31, 2019, the Company had cash, cash equivalents and marketable securities of approximately $30,879,000. Management believes that current cash, cash equivalents and marketable securities on hand at March 31, 2019 should be sufficient to fund operations for at least the next twelve months from the date of issuance of these financial statements; however, the future viability of the Company is dependent on its ability to raise additional capital to finance its operations and to fund increased research and development costs in order to seek approval for commercialization of its product candidates. The Company’s failure to raise capital as and when needed would have a negative impact on its financial condition and its ability to pursue its business strategies as this capital is necessary for the Company to perform the research and development activities required to develop the Company’s product candidates in order to generate future revenue streams.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Basis of Presentation The accompanying unaudited consolidated financial statements as of March 31, 2019, and for the three months ended March 31, 2019 and 2018, have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission (the “SEC”) and Generally Accepted Accounting Principles in the United States (“U.S. GAAP”) for financial information, which prescribes elimination of all significant intercompany accounts and transactions in the accounts of the Company and its wholly owned subsidiary Cue Biopharma Securities Corporation, Inc. which was formed in December 2018 and incorporated in the Commonwealth of Massachusetts. In the opinion of management, these financial statements reflect all adjustments which are necessary for a fair statement of the Company’s financial position and results of its operations, as of and for the periods presented Interim results for the three months ended March 31, 2019 are not necessarily indicative of the results that may be expected for the fiscal year ending December 31, 2019, or any future periods. Consolidation The accompanying consolidated financial statements include the Company and its wholly-owed subsidiary, Cue Biopharma Securities Corporation, Inc. The Company has eliminated all intercompany transactions for the three months ended March 31, 2019. Reclassification Certain amounts previously reported in current liabilities for the prior period have been reclassified to the current period presentation to segregate accounts payable and accrued liabilities to conform with current period presentation. Also, certain amounts previously reported in research and development contract advances have been reclassified to the current period presentation to combine research and development contract advances and prepaid expenses. In addition, certain amounts previously reported as reductions to research and development expenses have been reclassified to collaboration revenue to conform with current period presentation. There was no impact to reported net loss. The reclassifications did not have a material impact on previously reported financial statements. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Significant estimates include estimates related to revenue, the accounting for potential liabilities and accrued expenses, the assumptions utilized in valuing stock-based compensation issued for services, the realization of deferred tax assets, and the useful life with respect to long-lived assets and intangibles. Actual results could differ from those estimates. Cash Concentrations The Company maintains its cash balances with a financial institution in Federally-insured accounts and may periodically have cash balances in excess of insurance limits. The Company maintains its accounts with a financial institution with a high credit rating. The Company has not experienced any losses to date and believes that it is not exposed to any significant credit risk on cash. Cash and Cash Equivalents The Company considers all highly liquid investments with a maturity of three months or less at the date of purchase to be cash equivalents. The Company currently invests available cash in money market funds. Marketable Securities Marketable securities consist of investments with original maturities greater than ninety days and less than one year from the balance sheet date. The Company classifies all of its investments as available-for-sale securities. Accordingly, these investments are recorded at fair value, which is based on quoted market prices. Unrealized gains and losses are recognized and determined on a specific identification basis and are included in other comprehensive loss. Realized gains and losses are determined on a specific identification basis and are included in other income (loss) on the income statement. Amortization and accretion of discounts and premiums is recorded in interest income. The Company currently invests available cash in United States Treasury obligations. Restricted Cash The Company purchased a $50,000 certificate of deposit to collateralize a credit card account with a commercial bank that was classified as short-term restricted cash as of March 31, 2019 and December 31, 2018. The Company also had $150,000 in restricted cash with a commercial bank to collateralize a credit card as of March 31, 2019 and December 31, 2018. Property and Equipment Property and equipment is recorded at cost. Major improvements are capitalized, while maintenance and repairs are charged to expense as incurred. Gains and losses from disposition of property and equipment are included in income and expense when realized. Amortization of leasehold improvements is provided using the straight-line method over the shorter of the lease term or the useful life of the underlying assets. Depreciation of property and equipment is provided using the straight-line method over the following estimated useful lives: Laboratory equipment 5 years Computer and office equipment 3 years Furniture and fixtures 3-8 years The Company recognizes depreciation and amortization expense in general and administrative expenses and in research and development expenses in the Company’s statements of operations, depending on how each category of property and equipment is utilized in the Company’s business activities. Trademark Trademark consists of the Company’s right, title and interest to the CUE BIOLOGICS Mark, and any derivative mark incorporating CUE, throughout the world, together with all associated goodwill and common law rights appurtenant thereto, including, but not limited to, any right, title and interest in any corporate name, company name, business, name, trade name, dba, domain name, or other source identifier incorporating CUE. The Company has classified the trademark as a component of other long-term assets, having a useful life of 15 years at March 31, 2019. The Company evaluates the status of this intangible asset for amortization and impairment at each quarter end and year end reporting date. Revenue Recognition The Company adopted Accounting Standards Codification, Topic 606, Revenue from Contracts with Customers (“ASC 606”), during 2018. The Company recognizes collaboration revenue under certain of the Company’s license or collaboration agreements that are within the scope of ASC 606. The Company’s contracts with customers typically include promises related to licenses to intellectual property and research and development services. If the license to the Company’s intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, the Company recognizes revenue from non-refundable, up-front fees allocated to the license when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are bundled with other promises, the Company utilizes judgement to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue from non-refundable, up-front fees. Accordingly, the transaction price is generally comprised of a fixed fee due at contract inception and variable consideration in the form of milestone payments due upon the achievement of specified events and tiered royalties earned when customers recognize net sales of licensed products. The Company measures the transaction price based on the amount of consideration to which it expects to be entitled in exchange for transferring the promised goods and/or services to the customer. The Company utilizes the “most likely amount” method to estimate the amount of variable consideration, to predict the amount of consideration to which it will be entitled for its one open contract. Amounts of variable consideration are included in the transaction price to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved. At the inception of each arrangement that includes development and regulatory milestone payments, the Company evaluates whether the associated event is considered probable of achievement and estimates the amount to be included in the transaction price using the most likely amount method. Currently, the Company has one contract with an option to acquire additional goods and/or services in the form of additional research and development services for additional product candidates. Research and Development Expenses Research and development expenses consist primarily of compensation costs, fees paid to consultants, outside service providers and organizations (including research institutes at universities), facility costs, and development and clinical trial costs with respect to the Company’s product candidates. Research and development expenses incurred under contracts are expensed ratably over the life of the underlying contracts, unless the achievement of milestones, the completion of contracted work, or other information indicates that a different pattern of performance is more appropriate. Other research and development expenses are charged to operations as incurred. Nonrefundable advance payments are recognized as an expense as the related services are performed. The Company evaluates whether it expects the services to be rendered at each quarter end and year end reporting date. If the Company does not expect the services to be rendered, the advance payment is charged to expense. Nonrefundable advance payments for research and development services are included in prepaid and other current assets on the balance sheet. To the extent that a nonrefundable advance payment is for contracted services to be performed within 12 months from the reporting date, such advance is included in current assets; otherwise, such advance is included in non-current assets. The Company evaluates the status of its research and development agreements and contracts, and the carrying amount of the related assets and liabilities, at each quarter end and year end reporting date, and adjusts the carrying amounts and their classification on the balance sheet as appropriate. Patent Expenses The Company is the exclusive worldwide licensee of, and has patent applications pending for, numerous domestic and foreign patents. Due to the significant uncertainty associated with the successful development of one or more commercially viable product candidates based on the Company’s research efforts and any related patent applications, all patent costs, including patent-related legal fees, filing fees and other costs are charged to expense as incurred. For the three months ended March 31, 2019 and 2018, patent expenses were $569,000 and $117,000, respectively. Licensing Fees and Costs Licensing fees and costs consist primarily of costs relating to the acquisition of the Company’s license agreement with the Albert Einstein College of Medicine (“Einstein”), including related royalties, maintenance fees, milestone payments and product development costs. Licensing fees and costs are charged to expense as incurred. Long-Lived Assets The Company reviews long-lived assets, consisting of property and equipment, for impairment at each fiscal year end or when events or changes in circumstances indicate the carrying value of these assets may exceed their current fair values. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to the estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated future cash flows, an impairment charge is recognized for the amount by which the carrying amount of the asset exceeds the fair value of the assets. Assets to be disposed of are separately presented in the balance sheet and reported at the lower of the carrying amount or fair value less costs to sell and are no longer depreciated. The Company has not historically recorded any impairment to its long-lived assets. In the future, if events or market conditions affect the estimated fair value to the extent that a long-lived asset is impaired, the Company will adjust the carrying value of these long-lived assets in the period in which the impairment occurs. During the three months ended March 31, 2019 and 2018, there were no disposals of property and equipment. Right of Use Asset and Operating Lease Liability In February 2016, the FASB issued ASU 2016-02, Leases (ASC 842), which supersedes the existing guidance for lease accounting, Leases (Topic 840). ASU 2016-02 requires a lessee to record a right-of-use asset and a corresponding lease liability, initially measured at the present value of the lease payments, on the balance sheet for all leases with terms longer than 12 months, as well as, the disclosure of key information about leasing arrangements. ASU 2016-02 requires recognition in the statement of operations of a single lease cost, calculated so that the cost of the lease is allocated over the lease term, generally on a straight-line basis. A modified retrospective transition approach is required for lessees for capital and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available. We elected to adopt the package of practical expedients, which among other things, allows us to carry forward the historical lease classification and combine lease and non-lease components as a single component. On January 1, 2019, the Company adopted ASC 842 using the modified retrospective method for all material leases that existed at or commenced after January 1, 2019. See Note 10 for additional details. The Company elected to apply the practical expedients in ASC 842-10-65-1 and therefore: 1. did not reassess its expired lease for its former headquarters at 675 West Kendall Cambridge, MA; 2. its two operating leases remain classified as operating leases; 3. did not re-assess initial direct costs for any existing leases; and 4. will not separate the lease and non-lease components. The adoption of ASC 842 did not have a material net impact on the Company’s Consolidated Statements of Operations as of the effective date of adoption. The following table approximates the impact that the adoption of ASC 842 had to the Company’s March 31, 2019 Consolidated Balance Sheet as impacted by the present value of future cash flows calculation against both the asset and liability: Balance without adoption of ASC 842 Adjustment as of January 1, 2019 As reported balance as of March 31, 2019 Deferred rent ($381,000) $381,000 $- Right of use asset $- $9,691,000 $8,691,000 Operating lease liability $- ($9,346,000) ($8,590,000) Stock-Based Compensation The Company periodically issues stock options to officers, directors, employees, Scientific and Clinical Advisory Board members, non-employees and consultants for services rendered. Such issuances vest and expire according to terms established at the issuance date. Stock-based payments to officers, directors and employees, including grants of employee stock options, are recognized in the financial statements based on their grant date fair values. Stock option grants, which are generally time-vested, are measured at the grant date fair value and charged to operations on a straight-line basis over the service period, which generally approximates the vesting term. The Company also grants performance-based awards to periodically to officers of the Company. The Company recognizes compensation costs related to performance awards over the requisite service period if and when the Company concludes that it is probable that the performance condition will be achieved. Stock options granted to members of the Company’s Scientific and Clinical Advisory Board, non-employees and outside consultants are valued at the grant date fair value and charged to operations on a straight-line basis over the service period, which generally approximates the vesting term. The fair value of stock options is determined utilizing the Black-Scholes option-pricing model, which is affected by several variables, including the risk-free interest rate, the expected dividend yield, the life of the equity award, the exercise price of the stock option as compared to the fair value of the common stock on the grant date, and the estimated volatility of the common stock over the term of the equity award. The risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of grant. Until the Company has established a trading market for its common stock, estimated volatility is based on the average historical volatilities of comparable public companies in a similar industry. The expected dividend yield is based on the current yield at the grant date; the Company has never declared or paid dividends and has no plans to do so for the foreseeable future. As permitted by Staff Accounting Bulletin No. 107, due to the Company’s lack of trading history and option activity, management utilizes the simplified method to estimate the expected term of options at the date of grant. The exercise price is determined based on the fair value of the Company’s common stock at the date of grant. The Company accounts for forfeitures as they occur. The Company recognizes the fair value of stock-based compensation in general and administrative expenses and in research and development expenses in the Company’s statements of operations, depending on the type of services provided by the recipient of the equity award. Comprehensive Income (Loss) Components of comprehensive income or loss, including net income or loss, are reported in the financial statements in the period in which they are recognized. Other comprehensive income or loss is defined as the change in equity during a period from transactions and other and other events and circumstances from non-owner sources. Net income (loss) and other comprehensive income (loss) are reported net of any related tax effect to arrive at comprehensive income (loss). Comprehensive loss includes net loss as well as changes in stockholders’ equity that result from transactions and economic events other than those with stockholders. The Company’s only element of other comprehensive loss in all periods presented was unrealized loss on available-for-sale securities. Earnings (Loss) Per Share The Company’s computation of earnings (loss) per share (“EPS”) for the respective periods includes basic and diluted EPS. Basic EPS is measured as the income (loss) attributable to common stockholders divided by the weighted average number of common shares outstanding for the period. Diluted EPS is similar to basic EPS but presents the dilutive effect on a per share basis of potential common shares that would result from the exercise of outstanding stock options and warrants as if they had been exercised at the beginning of the periods presented, or issuance date, if later. Potential common shares that have an anti-dilutive effect (i.e., those that increase income per share or decrease loss per share) are excluded from the calculation of diluted EPS. Basic and diluted loss per common share is the same for all periods presented because all outstanding stock options and warrants are anti-dilutive. At March 31, 2019 and 2018, the Company excluded the outstanding securities summarized below, which entitle the holders thereof to acquire shares of common stock, from its calculation of earnings per share, as their effect would have been anti-dilutive. March 31, 2019 2018 Common stock warrants 1,252,441 1,252,441 Common stock options 5,214,753 2,757,221 Total 6,467,194 4,009,662 Fair Value of Financial Instruments The authoritative guidance with respect to fair value established a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value into three levels and requires that assets and liabilities carried at fair value be classified and disclosed in one of three categories, as presented below. Level 1. Observable inputs such as quoted prices in active markets for an identical asset or liability that the Company has the ability to access as of the measurement date. Financial assets and liabilities utilizing Level 1 inputs include active-exchange traded securities and exchange-based derivatives. Level 2. Inputs, other than quoted prices included within Level 1, which are directly observable for the asset or liability or indirectly observable through corroboration with observable market data. Financial assets and liabilities utilizing Level 2 inputs include fixed income securities, non-exchange based derivatives, mutual funds, and fair-value hedges. Level 3. Unobservable inputs in which there is little or no market data for the asset or liability which requires the reporting entity to develop its own assumptions. Financial assets and liabilities utilizing Level 3 inputs include infrequently-traded non-exchange-based derivatives and commingled investment funds and are measured using present value pricing models. The Company determines the level in the fair value hierarchy within which each fair value measurement falls in its entirety, based on the lowest level input that is significant to the fair value measurement in its entirety. In determining the appropriate levels, the Company performs an analysis of the assets and liabilities at each reporting period end. The Company had $21,913,385 in cash equivalents and $8,966,250 in short-term marketable securities that were measured and recorded at fair value on the Company’s balance sheet as of March 31, 2019. There were no financial instruments that were measured and recorded at fair value on the Company’s balance sheet as of March 31, 2018. The carrying value of financial instruments (consisting of cash, a certificate of deposit, accounts payable, accrued compensation and accrued expenses) is considered to be representative of their respective fair values due to the short-term nature of those instruments. Recent Accounting Pronouncements and Adopted Standards In February 2016, the FASB issued Accounting Standards Update No. 2016-02, Leases (Topic 842) (“ASU 2016-02”). ASU 2016-02 requires a lessee to record a right-of-use asset and a corresponding lease liability, initially measured at the present value of the lease payments, on the balance sheet for all leases with terms longer than 12 months, as well as the disclosure of key information about leasing arrangements. ASU 2016-02 requires recognition in the statement of operations of a single lease cost, calculated so that the cost of the lease is allocated over the lease term, generally on a straight-line basis. ASU 2016-02 requires classification of all cash payments within operating activities in the statement of cash flows. Disclosures are required to provide the amount, timing and uncertainty of cash flows arising from leases. A modified retrospective transition approach is required for lessees for capital and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available. We elected to adopt the package of practical expedients, which among other things, allows us to carry forward the historical lease classification and combine lease and non-lease components as a single component. ASU 2016-02 is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early application is permitted. The Company adopted the provisions of ASU 2016-02 on January 1, 2019 which resulted in a recognition of a right of use asset of approximately $9,692,000 and lease liability of approximately $9,347,000. There was no cumulative adjustment to retained earnings as a result of this adoption. This adoption resulted in a balance sheet presentation that is not be comparable to the prior period in the first year of adoption. As of March 31, 2019, the Company recorded a right of use asset of approximately $8,691,000 and lease liability of approximately $8,590,000. The change in the right of use asset and lease liability are due to rental payments made during the three months ended March 31, 2019. Management does not believe that any other recently issued, but not yet effective, authoritative guidance, if currently adopted, would have a material impact on the Company’s financial statement presentation or disclosures.

Fair Value

Fair Value	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value	3. The Company accounts for its financial assets and liabilities using fair value measurements. The authoritative accounting guidance defines fair value, establishes a framework for measuring fair value under generally accepted accounting principles and enhances disclosures about fair value measurements. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The following table presents information about the Company’s assets that are measured at fair value on a recurring basis as of March 31, 2019 and indicate the level of the fair value hierarchy utilized to determine such fair value: Fair Value Measurements as of March 31, 2019 (in thousands) Level 1 Level 2 Level 3 Fair Value Cash equivalents $ 16,176 $ — $ — $ 16,176 Marketable securities — 8,966 — 8,966 Total $ 16,176 $ 8,966 $ — $ 25,142 Fair Value Measurements as of December 31, 2018 (in thousands) Level 1 Level 2 Level 3 Fair Value Cash equivalents $ 10,548 $ — $ — $ 10,548 Marketable securities — 18,412 — 18,412 Total $ 10,548 $ 18,412 $ — $ 28,960 As of March 31, 2019, the Company’s cash equivalents that are invested in money market funds valued using Level 1 inputs for identical securities. The Company measures the fair value of marketable securities that are invested in United States Treasury securities using Level 2 inputs and primarily relies on quoted prices in active markets for similar marketable securities. During the three months ended March 31, 2019, there were no transfers between Level 2 and Level 3. As of December 31, 2018, the Company reported approximately $28,960,000 of cash equivalents and marketable securities. During the year ended December 31, 2018, there were no transfers between Level 2 and Level 3. The carrying values of accounts receivable, prepaid expenses, other current assets, accounts payable and accrued expenses approximate their fair value due to the short-term nature of these balances.

Marketable Securities

Marketable Securities	3 Months Ended
	Mar. 31, 2019
Investments Debt And Equity Securities [Abstract]
Marketable Securities	4. Marketable Securities As of March 31, 2019, the fair value of available-for-sale marketable securities by type of security was as follows: March 31, 2019 (In thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury Securities $ 8,969 $ — $ (3 ) $ 8,966 $ 8,969 $ — $ (3 ) $ 8,966 December 31, 2018 (In thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury Securities $ 18,424 $ — $ (11 ) $ 18,413 $ 18,424 $ — $ (11 ) $ 18,413 At March 31, 2019, marketable securities consisted of approximately $8,966,000 of investments that mature within twelve months. At December 31, 2018, marketable securities consisted of approximately $18,413,000 of investments that mature within twelve months.

Property and Equipment

Property and Equipment	3 Months Ended
	Mar. 31, 2019
Property Plant And Equipment [Abstract]
Property and Equipment	5 . Property and equipment as of March 31, 2019 and December 31, 2018 consisted of the following: March 31, 2019 December 31, 2018 (in thousands) Computer equipment $ 192 $ 182 Laboratory equipment 3,881 3,872 Furniture and fixtures 93 93 4,166 4,147 Less: Accumulated depreciation $ (1,571 ) $ (1,366 ) Total property and equipment, net $ 2,595 $ 2,781 Depreciation expense for the three months ended March 31, 2019 and 2018 was approximately $205,000 and $167,000, respectively.

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	6 . For stock options requiring an assessment of value during the three months ended March 31, 2019, the fair value of each stock option award was estimated using the Black-Scholes option-pricing model utilizing the following assumptions: March 31, 2019 Risk-free interest rate 2.49 to 2.59% Expected dividend yield 0% Expected volatility 82.0-90.2% Expected life 4.0 to 6.25 years A summary of stock option activity for the three months ended March 31, 2019 is as follows: Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in Years) Stock options outstanding at December 31, 2018 4,540,321 $ 4.07 5.76 Granted 774,600 6.33 Exercised (85,793 ) — Cancelled (14,375 ) — Stock options outstanding at March 31, 2019 5,214,753 7.03 5.88 Stock options exercisable at March 31, 2019 1,912,524 $ 5.62 4.78 As of March 31, 2019, total unrecognized stock-based compensation was approximately $16,123,087, which is expected to be recognized as an operating expense in the Company’s statement of operations through July 2022. The intrinsic value of exercisable but unexercised in-the-money stock options at March 31, 2019 was approximately $398,642, based on a fair value of $7.73 per share on March 29, 2019. Stock-based compensation for the three months ended March 31, 2019 and 2018 was included in the statement of operations as follows: Three Months Ended March 31, (in thousands) 2019 2018 General and administrative $ 560 $ 380 Research and development 1,208 778 Total $ 1,768 $ 1,158

Warrants

Warrants	3 Months Ended
	Mar. 31, 2019
Warrants And Rights Note Disclosure [Abstract]
Warrants	7 . Warrants The Company had two tranches of common stock warrants outstanding at March 31, 2019. The first tranche is exercisable for 370,370 shares of common stock issued on June 15, 2015 with an exercise price of $2.70 per share. These warrants were issued with a 7 year life and expire on June 15, 2022. The second tranche is exercisable for 882,071 shares of common stock was issued on December 27, 2017 with an exercise price of $9.38 per share. These warrants were issued with a 5 year life and expire on December 26, 2022. The intrinsic value of exercisable but unexercised in-the-money common stock warrants at March 31, 2019 was approximately $1,863,000 based on a fair value of $7.73 per share on March 29, 2019. Each tranche of warrants was evaluated under ASC 480, Distinguishing Liabilities from Equity, and ASC 815, Derivatives and Hedging , and the Company determined that equity classification was appropriate.

Revenue Recognition

Revenue Recognition	3 Months Ended
	Mar. 31, 2019
Revenue From Contract With Customer [Abstract]
Revenue Recognition	8 . Revenue Recognition The Company recognizes collaboration revenue under certain of the Company’s license or collaboration agreements that are within the scope of ASC 606. The Company’s contracts with customers typically include promises related to licenses to intellectual property and research and development services. If the license to the Company’s intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, the Company recognizes revenue from non-refundable, up-front fees allocated to the license when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are bundled with other promises, the Company utilizes judgement to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue from non-refundable, up-front fees. The Company’s contracts may include options to acquire additional goods and/or services. The terms of the Company’s arrangements with customers typically include the payment of one or more of the following: (i) Non-refundable, up-front payment, (ii) Development, regulatory and commercial milestone payments, (iii) Future options and (iv) Royalties on net sales of licensed products. Accordingly, the transaction price is generally comprised of a fixed fee due at contract inception and variable consideration in the form of milestone payments due upon the achievement of specified events and tiered royalties earned when customers recognize net sales of licensed products. The Company measures the transaction price based on the amount of consideration to which it expects to be entitled in exchange for transferring the promised goods and/or services to the customer. The Company utilizes the “most likely amount” method to estimate the amount of variable consideration, to predict the amount of consideration to which it will be entitled for its one open contract. Amounts of variable consideration are included in the transaction price to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved. Milestone payments that are not within the control of the Company or the licensee, such as those dependent upon receipt of regulatory approval, are not considered to be probable of achievement until the triggering event occurs. At the end of each reporting period, the Company reevaluates the probability of achievement of each milestone and any related constraint, and if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenue and net loss in the period of adjustment. For arrangements that include sales-based royalties, including milestone payments based upon the achievement of a certain level of product sales, the Company recognizes revenue upon the later of: (i) When the related sales occur or (ii) When the performance obligation to which some or all of the payment has been allocated has been satisfied (or partially satisfied). To date, the Company has not recognized any development, regulatory or commercial milestones or royalty revenue resulting from any of its collaboration arrangements. Consideration that would be received for optional goods and/or services is excluded from the transaction price at contract inception. The Company allocates the transaction price to each performance obligation identified in the contract on a relative standalone selling price basis, when applicable. However, certain components of variable consideration are allocated specifically to one or more particular performance obligations in a contact to the extent both of the following criteria are met: (i) The terms of the payment relate specifically to the efforts to satisfy the performance obligation or transfer the distinct good or service and (ii) Allocating the variable amount of consideration entirely to the performance obligation or the distinct good or service is consistent with the allocation objective of the standard whereby the amount allocated depicts the amount of consideration to which the entity expects to be entitled in exchange for transferring the promised goods or services. The Company develops assumptions that require judgement to determine the standalone selling price for each performance obligation identified in each contract. The key assumptions utilized in determining the standalone selling price for each performance obligation may include forecasted revenues, development timelines, estimated research and development costs, discount rates, likelihood of exercise and probabilities of technical and regulatory success. Revenue is recognized based on the amount of the transaction price that is allocated to each respective performance obligation when or as the performance obligation is satisfied by transferring a promised good and/or service to the customer. For performance obligations that are satisfied over time, the Company recognizes revenue by measuring the progress toward complete satisfaction of the performance obligation using a single method of measuring progress which depicts the performance in transferring control of the associated goods and/or services to the customer. The Company uses input methods to measure the progress toward the complete satisfaction of performance obligations satisfied over time. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenue and net loss in the period of adjustment. As it relates to the Merck The Company does not believe that any variable consideration should be included in the transaction price at March 31, 2019. Such assessment considered the application of the constraint to ensure that estimates of variable consideration would be included in the transaction price only to the extent the Company had a high degree of confidence that revenue would not be reversed in a subsequent reporting period. The Company will re-evaluate the transaction price, including the estimated variable consideration included in the transaction price and all constrained amounts, in each reporting period and as other changes in circumstances occur. For the three months ended March 31, 2019, the Company recognized $370,000 in collaboration revenue related to this agreement and recorded short and long-term research and development liabilities on its balance sheet dated March 31, 2019 of $893,157 and $94,160, respectively. On November 6, 2018, the Company entered into a Collaboration Agreement with LG Chem related to the development of the Company’s Immuno-STATs focused in the field of oncology. Pursuant to the Collaboration Agreement the Company granted LG Chem an exclusive license to develop, manufacture and commercialize the Company’s lead product, CUE-101, as well as Immuno-STATs that target T-cells against two additional cancer antigens, in certain Asian countries (collectively, the “LG Chem Territory”). LG Chem has the option to elect one additional Immuno-STAT for an oncology target within two years of the agreement for a worldwide development and commercialization license, and Cue Biopharma will retain an option to co-develop and co-commercialize the additional program worldwide. Cue Biopharma retains rights to develop and commercialize all assets included in the agreement in the United States and in global markets outside of Asia. In exchange for the licenses and other rights granted to LG Chem under the Collaboration Agreement, LG Chem will make a $5.0 million equity investment in common stock of Cue Biopharma, Inc. and a $5.0 million nonrefundable upfront cash payment. Cue Biopharma is also be eligible to receive up to an additional $400 million in research, development, regulatory and sales milestones. In addition, the Collaboration Agreement also provides that LG Chem will pay the Company tiered single-digit royalties on net sales of commercialized product candidates in the LG Chem Territory. As it relates to the LG Chem The Company does not believe that any variable consideration should be included in the transaction price as of March 31, 2019. Such assessment considered the application of the constraint to ensure that estimates of variable consideration would be included in the transaction price only to the extent the Company had a high degree of confidence that revenue would not be reversed in a subsequent reporting period. The Company will re-evaluate the transaction price, including the estimated variable consideration included in the transaction price and all constrained amounts, in each reporting period and as other changes in circumstances occur. For the three months ended March 31, 2019, the Company did not recognized revenue related to this agreement. The Company considered the capitalization of contract costs under the guidance in ASC 340-40, Other Assets and Deferred Costs: Contracts with Customers

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2019
Related Party Transactions [Abstract]
Related Party Transactions	9 . R The former interim Chief Financial Officer of the Company, who is also the Chief Financial Officer of MDB, a related party, was compensated at a rate of $6,000 per month, reflecting an aggregate charge to operations for the three months ended March 31, 2019 and 2018 of $0 and $18,000, respectively.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	10 . Einstein License and Service Agreement In 2015, the Company entered into the Einstein License with Einstein for certain patent rights relating to the Company’s core technology platform for the engineering of biologics to control T-cell activity, precision, immune-modulatory drug candidates, and two supporting technologies that enable the discovery of costimulatory signaling molecules (ligands) and T-cell targeting peptides. On July 31, 2017, the Company entered into an amended and restated license agreement which modified certain obligations of the parties under the Einstein License. For the three months ended March 31, 2019 and 2018, the Company incurred approximately $12,500 and $10,000, respectively, in fees and expenses to Einstein in relation to this license. The Company’s remaining commitments with respect to the Einstein License are based on the attainment of future milestones. The aggregate amount of milestone payments made under the Einstein License may equal up to $1.85 million for each product, process or service that use the patents covered by the Einstein License, including certain technology received from Einstein relating thereto (“Licensed Products”), and up to $1.85 million for each new indication of a Licensed Product. Additionally, the aggregate amount of one-time milestone payments based on cumulative sales of all Licensed Products may equal up to $5.75 million. The Company is also party to a service agreement with Einstein to support the Company’s ongoing research and development activities. Agreements with Catalent On March 7, 2017, the Company entered into an agreement with Catalent Pharma Solutions, LLC (“Catalent”) for Catalent to provide services on a sequential milestone basis with respect to the development and manufacture of the Company’s lead drug candidate, CUE-101. The services under the agreement are designed to support the preparation and filing of an Investigational New Drug Application with the United States Food and Drug Administration to allow for the commencement of a Phase 1 clinical trial of CUE-101 in the United States. The Company incurred total direct costs under this agreement aggregating $0.6 million during the three months ended March 31, 2019 and currently estimates that it will incur an additional $0.2 million of such costs for the year ended December 31, 2019. Certain of these agreements contain nonrefundable advance payments for which the Company anticipates receiving the contracted services within 12 months from the date of payment. Management periodically reviews and updates the project’s estimated budget and timeline. Collaboration Agreement with Merck On November 14, 2017, the Company entered into the Collaboration Agreement with Merck for a partnership to research and develop certain of the Company’s proprietary biologics that target certain autoimmune disease indications (the “Initial Indications”). We view this Collaboration Agreement as a component of our development strategy since it will allow us to advance our autoimmune programs in partnership with a world class pharmaceutical company, while also continuing our focus on our more advanced cancer programs. The research program outlined in the Collaboration Agreement entails (1) our research, discovery and development of certain Immuno-STAT™ drug candidates up to the point of demonstration of certain biologically relevant effects (“Proof of Mechanism”) and (2) the further development by Merck of the Immuno-STAT™ drug candidates that have demonstrated Proof of Mechanism (the “Proposed Product Candidates”) up to the point of demonstration of all or substantially all of the properties outlined in such Proposed Product Candidates’ profiles as described in the Collaboration Agreement. In exchange for the licenses and other rights granted to Merck under the Collaboration Agreement, Merck paid to the Company a $2.5 million nonrefundable up-front payment. Additionally, the Company may be eligible to receive funding in developmental milestone payments, as well as tiered royalties, if all research, development, regulatory and commercial milestones agreed upon by both parties are successfully achieved. Excluding the up-front payment described above, the Company is eligible to earn up to $101 million for the achievement of certain research and development milestones, $120 million for the achievement of certain regulatory milestones and $150 million for the achievement of certain commercial milestones, in addition to tiered royalties on sales, if all pre-specified milestones associated with multiple products across the primary disease indication areas are achieved. The Collaboration Agreement requires the Company to use the first $2.5 million of milestone payments we receive under the agreement to fund contract research. The amount of the royalty payments is a percentage of product sales ranging in the single digits based on the amount of such sales. For the three months ended March 31, 2019 and 2018, the Company recorded approximately $370,000 and $0 in collaboration revenue related to this agreement. Collaboration Agreement with LG Chem Life Sciences On November 6, 2018, the Company entered into a Collaboration Agreement with LG Chem Life Sciences. related to the development of the Company’s Immuno-STATs focused in the field of oncology. Pursuant to the Collaboration Agreement the Company granted LG Chem an exclusive license to develop, manufacture and commercialize the Company’s lead product, CUE-101, as well as Immuno-STATs that target T-cells against two additional cancer antigens, in certain Asian countries (collectively, the “LG Chem Territory”). LG Chem has the option to elect one additional Immuno-STAT for an oncology target within two years of the agreement for a worldwide development and commercialization license, and Cue Biopharma will retain an option to co-develop and co-commercialize the additional program worldwide. Cue Biopharma retains rights to develop and commercialize all assets included in the agreement in the United States and in global markets outside of Asia. In exchange for the licenses and other rights granted to LG Chem under the Collaboration Agreement, LG Chem will make a $5.0 million equity investment in common stock of Cue Biopharma, Inc. and a $5.0 million nonrefundable upfront cash payment. Cue Biopharma is also be eligible to receive up to an additional $400 million in research, development, regulatory and sales milestones. In addition, the Collaboration Agreement also provides that LG Chem will pay the Company tiered single-digit royalties on net sales of commercialized product candidates in the LG Chem Territory. There was no revenue recognized for the three months ended March 31, 2019 related to this agreement. Leased Facilities On July 29, 2015, the Company entered into an operating lease agreement for its laboratory space for the period from August 1, 2015 through April 30, 2018. The lease contains escalating payments during the lease period. The Company records monthly rent expense on the straight-line basis, equal to the total of the lease payments over the lease term divided by the number of months of the lease term. On November 14, 2016, June 28, 2017, and January 16, 2018, the Company entered into amendments to the operating lease agreement that each provided the Company with additional laboratory space. These amendments were effective beginning December 1, 2016 and July 1, 2017, and January 16, 2018, respectively, and continue through the expiration of the lease on April 30, 2018. On January 18, 2018, the Company entered into an operating lease agreement for laboratory space to commence following the expiration of is current lease agreement described above with a term continuing until April 30, 2021. The monthly rental rate under the lease agreement is $297,500 for the first 18 months and $330,500 for the remainder of the term. Pursuant to the terms of the lease agreement, the Company prepaid three months’ of rent payments upon entering into the lease agreement. On June 18, 2018, the Company entered into an amended lease agreement that provided the Company with a reduction in rental fees for its office and laboratory space in exchange for prepayment of a portion of the fees. This amendment was effective beginning on May 15, 2018 and expires on April 14, 2021. On September 20, 2018, the Company entered into an operating lease for additional laboratory space in Cambridge, Massachusetts for the period from October 15, 2018 through April 14, 2021. The lease contains escalating payments during the lease period. The monthly rental rate under the lease agreement is $72,600 for the first 12 months and $78,600 for the remainder of the term. Upon execution of this lease agreement the Company prepaid three months of rent which will be held in escrow and credited against future rent payments. The Company also prepaid twelve months rent pursuant to the lease agreement executed on September 20, 2018. Approximately $236,000 and $727,000 were recorded to deposits and right of use asset, respectively, for the three months ended March 31, 2019. Future minimum lease payments under these leases at March 31, 2019 are as follows: Year (in thousands) 2019 $ 2,842 2020 4,910 2021 1,432 Total lease payment $ 9,184 Less: present value discount (594 ) Total $ 8,590 Total rent expense of approximately $1,137,000 and $670,000 was included in the statement of operations for the three months ended March 31, 2019 and 2018, respectively. Contingencies The Company accrues for contingent liabilities to the extent that the liability is probable and estimable. There are no accruals for contingent liabilities in these consolidated financial statements. The Company may be subject to various legal proceedings from time to time as part of its business. As of March 31, 2019, the Company was not a party to any legal proceedings or threatened legal proceedings, the adverse outcome of which, individually or in the aggregate, would have a material adverse effect on its business, financial condition or results of operations.

Subsequent Event

Subsequent Event	3 Months Ended
	Mar. 31, 2019
Subsequent Events [Abstract]
Subsequent Events	11. Subsequent Event The Company has evaluated subsequent events through the date on which the consolidated financial statements were issued, to ensure that this submission includes appropriate disclosure of events both recognized in the consolidated financial statements and events which occurred subsequently but were not recognized in the consolidated financial statements.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited consolidated financial statements as of March 31, 2019, and for the three months ended March 31, 2019 and 2018, have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission (the “SEC”) and Generally Accepted Accounting Principles in the United States (“U.S. GAAP”) for financial information, which prescribes elimination of all significant intercompany accounts and transactions in the accounts of the Company and its wholly owned subsidiary Cue Biopharma Securities Corporation, Inc. which was formed in December 2018 and incorporated in the Commonwealth of Massachusetts. In the opinion of management, these financial statements reflect all adjustments which are necessary for a fair statement of the Company’s financial position and results of its operations, as of and for the periods presented Interim results for the three months ended March 31, 2019 are not necessarily indicative of the results that may be expected for the fiscal year ending December 31, 2019, or any future periods.
Consolidation	Consolidation The accompanying consolidated financial statements include the Company and its wholly-owed subsidiary, Cue Biopharma Securities Corporation, Inc. The Company has eliminated all intercompany transactions for the three months ended March 31, 2019.
Reclassification	Reclassification Certain amounts previously reported in current liabilities for the prior period have been reclassified to the current period presentation to segregate accounts payable and accrued liabilities to conform with current period presentation. Also, certain amounts previously reported in research and development contract advances have been reclassified to the current period presentation to combine research and development contract advances and prepaid expenses. In addition, certain amounts previously reported as reductions to research and development expenses have been reclassified to collaboration revenue to conform with current period presentation. There was no impact to reported net loss. The reclassifications did not have a material impact on previously reported financial statements.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Significant estimates include estimates related to revenue, the accounting for potential liabilities and accrued expenses, the assumptions utilized in valuing stock-based compensation issued for services, the realization of deferred tax assets, and the useful life with respect to long-lived assets and intangibles. Actual results could differ from those estimates.
Cash Concentrations	Cash Concentrations The Company maintains its cash balances with a financial institution in Federally-insured accounts and may periodically have cash balances in excess of insurance limits. The Company maintains its accounts with a financial institution with a high credit rating. The Company has not experienced any losses to date and believes that it is not exposed to any significant credit risk on cash.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with a maturity of three months or less at the date of purchase to be cash equivalents. The Company currently invests available cash in money market funds.
Marketable Securities	Marketable Securities Marketable securities consist of investments with original maturities greater than ninety days and less than one year from the balance sheet date. The Company classifies all of its investments as available-for-sale securities. Accordingly, these investments are recorded at fair value, which is based on quoted market prices. Unrealized gains and losses are recognized and determined on a specific identification basis and are included in other comprehensive loss. Realized gains and losses are determined on a specific identification basis and are included in other income (loss) on the income statement. Amortization and accretion of discounts and premiums is recorded in interest income. The Company currently invests available cash in United States Treasury obligations.
Restricted Cash	Restricted Cash The Company purchased a $50,000 certificate of deposit to collateralize a credit card account with a commercial bank that was classified as short-term restricted cash as of March 31, 2019 and December 31, 2018. The Company also had $150,000 in restricted cash with a commercial bank to collateralize a credit card as of March 31, 2019 and December 31, 2018.
Property and Equipment	Property and Equipment Property and equipment is recorded at cost. Major improvements are capitalized, while maintenance and repairs are charged to expense as incurred. Gains and losses from disposition of property and equipment are included in income and expense when realized. Amortization of leasehold improvements is provided using the straight-line method over the shorter of the lease term or the useful life of the underlying assets. Depreciation of property and equipment is provided using the straight-line method over the following estimated useful lives: Laboratory equipment 5 years Computer and office equipment 3 years Furniture and fixtures 3-8 years The Company recognizes depreciation and amortization expense in general and administrative expenses and in research and development expenses in the Company’s statements of operations, depending on how each category of property and equipment is utilized in the Company’s business activities.
Trademark	Trademark Trademark consists of the Company’s right, title and interest to the CUE BIOLOGICS Mark, and any derivative mark incorporating CUE, throughout the world, together with all associated goodwill and common law rights appurtenant thereto, including, but not limited to, any right, title and interest in any corporate name, company name, business, name, trade name, dba, domain name, or other source identifier incorporating CUE. The Company has classified the trademark as a component of other long-term assets, having a useful life of 15 years at March 31, 2019. The Company evaluates the status of this intangible asset for amortization and impairment at each quarter end and year end reporting date.
Revenue Recognition	Revenue Recognition The Company adopted Accounting Standards Codification, Topic 606, Revenue from Contracts with Customers (“ASC 606”), during 2018. The Company recognizes collaboration revenue under certain of the Company’s license or collaboration agreements that are within the scope of ASC 606. The Company’s contracts with customers typically include promises related to licenses to intellectual property and research and development services. If the license to the Company’s intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, the Company recognizes revenue from non-refundable, up-front fees allocated to the license when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are bundled with other promises, the Company utilizes judgement to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue from non-refundable, up-front fees. Accordingly, the transaction price is generally comprised of a fixed fee due at contract inception and variable consideration in the form of milestone payments due upon the achievement of specified events and tiered royalties earned when customers recognize net sales of licensed products. The Company measures the transaction price based on the amount of consideration to which it expects to be entitled in exchange for transferring the promised goods and/or services to the customer. The Company utilizes the “most likely amount” method to estimate the amount of variable consideration, to predict the amount of consideration to which it will be entitled for its one open contract. Amounts of variable consideration are included in the transaction price to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved. At the inception of each arrangement that includes development and regulatory milestone payments, the Company evaluates whether the associated event is considered probable of achievement and estimates the amount to be included in the transaction price using the most likely amount method. Currently, the Company has one contract with an option to acquire additional goods and/or services in the form of additional research and development services for additional product candidates.
Research and Development Expenses	Research and Development Expenses Research and development expenses consist primarily of compensation costs, fees paid to consultants, outside service providers and organizations (including research institutes at universities), facility costs, and development and clinical trial costs with respect to the Company’s product candidates. Research and development expenses incurred under contracts are expensed ratably over the life of the underlying contracts, unless the achievement of milestones, the completion of contracted work, or other information indicates that a different pattern of performance is more appropriate. Other research and development expenses are charged to operations as incurred. Nonrefundable advance payments are recognized as an expense as the related services are performed. The Company evaluates whether it expects the services to be rendered at each quarter end and year end reporting date. If the Company does not expect the services to be rendered, the advance payment is charged to expense. Nonrefundable advance payments for research and development services are included in prepaid and other current assets on the balance sheet. To the extent that a nonrefundable advance payment is for contracted services to be performed within 12 months from the reporting date, such advance is included in current assets; otherwise, such advance is included in non-current assets. The Company evaluates the status of its research and development agreements and contracts, and the carrying amount of the related assets and liabilities, at each quarter end and year end reporting date, and adjusts the carrying amounts and their classification on the balance sheet as appropriate.
Patent Expenses	Patent Expenses The Company is the exclusive worldwide licensee of, and has patent applications pending for, numerous domestic and foreign patents. Due to the significant uncertainty associated with the successful development of one or more commercially viable product candidates based on the Company’s research efforts and any related patent applications, all patent costs, including patent-related legal fees, filing fees and other costs are charged to expense as incurred. For the three months ended March 31, 2019 and 2018, patent expenses were $569,000 and $117,000, respectively.
Licensing Fees and Costs	Licensing Fees and Costs Licensing fees and costs consist primarily of costs relating to the acquisition of the Company’s license agreement with the Albert Einstein College of Medicine (“Einstein”), including related royalties, maintenance fees, milestone payments and product development costs. Licensing fees and costs are charged to expense as incurred.
Long-Lived Assets	Long-Lived Assets The Company reviews long-lived assets, consisting of property and equipment, for impairment at each fiscal year end or when events or changes in circumstances indicate the carrying value of these assets may exceed their current fair values. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to the estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated future cash flows, an impairment charge is recognized for the amount by which the carrying amount of the asset exceeds the fair value of the assets. Assets to be disposed of are separately presented in the balance sheet and reported at the lower of the carrying amount or fair value less costs to sell and are no longer depreciated. The Company has not historically recorded any impairment to its long-lived assets. In the future, if events or market conditions affect the estimated fair value to the extent that a long-lived asset is impaired, the Company will adjust the carrying value of these long-lived assets in the period in which the impairment occurs. During the three months ended March 31, 2019 and 2018, there were no disposals of property and equipment.
Right of Use Asset and Operating Lease Liability	Right of Use Asset and Operating Lease Liability In February 2016, the FASB issued ASU 2016-02, Leases (ASC 842), which supersedes the existing guidance for lease accounting, Leases (Topic 840). ASU 2016-02 requires a lessee to record a right-of-use asset and a corresponding lease liability, initially measured at the present value of the lease payments, on the balance sheet for all leases with terms longer than 12 months, as well as, the disclosure of key information about leasing arrangements. ASU 2016-02 requires recognition in the statement of operations of a single lease cost, calculated so that the cost of the lease is allocated over the lease term, generally on a straight-line basis. A modified retrospective transition approach is required for lessees for capital and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available. We elected to adopt the package of practical expedients, which among other things, allows us to carry forward the historical lease classification and combine lease and non-lease components as a single component. On January 1, 2019, the Company adopted ASC 842 using the modified retrospective method for all material leases that existed at or commenced after January 1, 2019. See Note 10 for additional details. The Company elected to apply the practical expedients in ASC 842-10-65-1 and therefore: 1. did not reassess its expired lease for its former headquarters at 675 West Kendall Cambridge, MA; 2. its two operating leases remain classified as operating leases; 3. did not re-assess initial direct costs for any existing leases; and 4. will not separate the lease and non-lease components. The adoption of ASC 842 did not have a material net impact on the Company’s Consolidated Statements of Operations as of the effective date of adoption. The following table approximates the impact that the adoption of ASC 842 had to the Company’s March 31, 2019 Consolidated Balance Sheet as impacted by the present value of future cash flows calculation against both the asset and liability: Balance without adoption of ASC 842 Adjustment as of January 1, 2019 As reported balance as of March 31, 2019 Deferred rent ($381,000) $381,000 $- Right of use asset $- $9,691,000 $8,691,000 Operating lease liability $- ($9,346,000) ($8,590,000)
Stock-Based Compensation	Stock-Based Compensation The Company periodically issues stock options to officers, directors, employees, Scientific and Clinical Advisory Board members, non-employees and consultants for services rendered. Such issuances vest and expire according to terms established at the issuance date. Stock-based payments to officers, directors and employees, including grants of employee stock options, are recognized in the financial statements based on their grant date fair values. Stock option grants, which are generally time-vested, are measured at the grant date fair value and charged to operations on a straight-line basis over the service period, which generally approximates the vesting term. The Company also grants performance-based awards to periodically to officers of the Company. The Company recognizes compensation costs related to performance awards over the requisite service period if and when the Company concludes that it is probable that the performance condition will be achieved. Stock options granted to members of the Company’s Scientific and Clinical Advisory Board, non-employees and outside consultants are valued at the grant date fair value and charged to operations on a straight-line basis over the service period, which generally approximates the vesting term. The fair value of stock options is determined utilizing the Black-Scholes option-pricing model, which is affected by several variables, including the risk-free interest rate, the expected dividend yield, the life of the equity award, the exercise price of the stock option as compared to the fair value of the common stock on the grant date, and the estimated volatility of the common stock over the term of the equity award. The risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of grant. Until the Company has established a trading market for its common stock, estimated volatility is based on the average historical volatilities of comparable public companies in a similar industry. The expected dividend yield is based on the current yield at the grant date; the Company has never declared or paid dividends and has no plans to do so for the foreseeable future. As permitted by Staff Accounting Bulletin No. 107, due to the Company’s lack of trading history and option activity, management utilizes the simplified method to estimate the expected term of options at the date of grant. The exercise price is determined based on the fair value of the Company’s common stock at the date of grant. The Company accounts for forfeitures as they occur. The Company recognizes the fair value of stock-based compensation in general and administrative expenses and in research and development expenses in the Company’s statements of operations, depending on the type of services provided by the recipient of the equity award.
Comprehensive Income (Loss)	Comprehensive Income (Loss) Components of comprehensive income or loss, including net income or loss, are reported in the financial statements in the period in which they are recognized. Other comprehensive income or loss is defined as the change in equity during a period from transactions and other and other events and circumstances from non-owner sources. Net income (loss) and other comprehensive income (loss) are reported net of any related tax effect to arrive at comprehensive income (loss). Comprehensive loss includes net loss as well as changes in stockholders’ equity that result from transactions and economic events other than those with stockholders. The Company’s only element of other comprehensive loss in all periods presented was unrealized loss on available-for-sale securities.
Earnings (Loss) Per Share	Earnings (Loss) Per Share The Company’s computation of earnings (loss) per share (“EPS”) for the respective periods includes basic and diluted EPS. Basic EPS is measured as the income (loss) attributable to common stockholders divided by the weighted average number of common shares outstanding for the period. Diluted EPS is similar to basic EPS but presents the dilutive effect on a per share basis of potential common shares that would result from the exercise of outstanding stock options and warrants as if they had been exercised at the beginning of the periods presented, or issuance date, if later. Potential common shares that have an anti-dilutive effect (i.e., those that increase income per share or decrease loss per share) are excluded from the calculation of diluted EPS. Basic and diluted loss per common share is the same for all periods presented because all outstanding stock options and warrants are anti-dilutive. At March 31, 2019 and 2018, the Company excluded the outstanding securities summarized below, which entitle the holders thereof to acquire shares of common stock, from its calculation of earnings per share, as their effect would have been anti-dilutive. March 31, 2019 2018 Common stock warrants 1,252,441 1,252,441 Common stock options 5,214,753 2,757,221 Total 6,467,194 4,009,662
Fair Value of Financial Instruments	Fair Value of Financial Instruments The authoritative guidance with respect to fair value established a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value into three levels and requires that assets and liabilities carried at fair value be classified and disclosed in one of three categories, as presented below. Level 1. Observable inputs such as quoted prices in active markets for an identical asset or liability that the Company has the ability to access as of the measurement date. Financial assets and liabilities utilizing Level 1 inputs include active-exchange traded securities and exchange-based derivatives. Level 2. Inputs, other than quoted prices included within Level 1, which are directly observable for the asset or liability or indirectly observable through corroboration with observable market data. Financial assets and liabilities utilizing Level 2 inputs include fixed income securities, non-exchange based derivatives, mutual funds, and fair-value hedges. Level 3. Unobservable inputs in which there is little or no market data for the asset or liability which requires the reporting entity to develop its own assumptions. Financial assets and liabilities utilizing Level 3 inputs include infrequently-traded non-exchange-based derivatives and commingled investment funds and are measured using present value pricing models. The Company determines the level in the fair value hierarchy within which each fair value measurement falls in its entirety, based on the lowest level input that is significant to the fair value measurement in its entirety. In determining the appropriate levels, the Company performs an analysis of the assets and liabilities at each reporting period end. The Company had $21,913,385 in cash equivalents and $8,966,250 in short-term marketable securities that were measured and recorded at fair value on the Company’s balance sheet as of March 31, 2019. There were no financial instruments that were measured and recorded at fair value on the Company’s balance sheet as of March 31, 2018. The carrying value of financial instruments (consisting of cash, a certificate of deposit, accounts payable, accrued compensation and accrued expenses) is considered to be representative of their respective fair values due to the short-term nature of those instruments.
Recent Accounting Pronouncements and Adopted Standards	Recent Accounting Pronouncements and Adopted Standards In February 2016, the FASB issued Accounting Standards Update No. 2016-02, Leases (Topic 842) (“ASU 2016-02”). ASU 2016-02 requires a lessee to record a right-of-use asset and a corresponding lease liability, initially measured at the present value of the lease payments, on the balance sheet for all leases with terms longer than 12 months, as well as the disclosure of key information about leasing arrangements. ASU 2016-02 requires recognition in the statement of operations of a single lease cost, calculated so that the cost of the lease is allocated over the lease term, generally on a straight-line basis. ASU 2016-02 requires classification of all cash payments within operating activities in the statement of cash flows. Disclosures are required to provide the amount, timing and uncertainty of cash flows arising from leases. A modified retrospective transition approach is required for lessees for capital and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available. We elected to adopt the package of practical expedients, which among other things, allows us to carry forward the historical lease classification and combine lease and non-lease components as a single component. ASU 2016-02 is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early application is permitted. The Company adopted the provisions of ASU 2016-02 on January 1, 2019 which resulted in a recognition of a right of use asset of approximately $9,692,000 and lease liability of approximately $9,347,000. There was no cumulative adjustment to retained earnings as a result of this adoption. This adoption resulted in a balance sheet presentation that is not be comparable to the prior period in the first year of adoption. As of March 31, 2019, the Company recorded a right of use asset of approximately $8,691,000 and lease liability of approximately $8,590,000. The change in the right of use asset and lease liability are due to rental payments made during the three months ended March 31, 2019. Management does not believe that any other recently issued, but not yet effective, authoritative guidance, if currently adopted, would have a material impact on the Company’s financial statement presentation or disclosures.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Summary of Estimated Useful Lives of Assets	Depreciation of property and equipment is provided using the straight-line method over the following estimated useful lives: Laboratory equipment 5 years Computer and office equipment 3 years Furniture and fixtures 3-8 years
Schedule of Consolidated Balance Sheet as Impacted by the Present Value of Future Cash Flows Calculation Against Both Asset and Liability	The following table approximates the impact that the adoption of ASC 842 had to the Company’s March 31, 2019 Consolidated Balance Sheet as impacted by the present value of future cash flows calculation against both the asset and liability Balance without adoption of ASC 842 Adjustment as of January 1, 2019 As reported balance as of March 31, 2019 Deferred rent ($381,000) $381,000 $- Right of use asset $- $9,691,000 $8,691,000 Operating lease liability $- ($9,346,000) ($8,590,000)
Schedule of Anti-dilutive Securities Excluded from Computation of Earnings Per Share	At March 31, 2019 and 2018, the Company excluded the outstanding securities summarized below, which entitle the holders thereof to acquire shares of common stock, from its calculation of earnings per share, as their effect would have been anti-dilutive. March 31, 2019 2018 Common stock warrants 1,252,441 1,252,441 Common stock options 5,214,753 2,757,221 Total 6,467,194 4,009,662

Fair Value (Tables)

Fair Value (Tables)	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Schedule of Fair Value Assets Measured on Recurring Basis	The following table presents information about the Company’s assets that are measured at fair value on a recurring basis as of March 31, 2019 and indicate the level of the fair value hierarchy utilized to determine such fair value: Fair Value Measurements as of March 31, 2019 (in thousands) Level 1 Level 2 Level 3 Fair Value Cash equivalents $ 16,176 $ — $ — $ 16,176 Marketable securities — 8,966 — 8,966 Total $ 16,176 $ 8,966 $ — $ 25,142 Fair Value Measurements as of December 31, 2018 (in thousands) Level 1 Level 2 Level 3 Fair Value Cash equivalents $ 10,548 $ — $ — $ 10,548 Marketable securities — 18,412 — 18,412 Total $ 10,548 $ 18,412 $ — $ 28,960

Marketable Securities (Tables)

Marketable Securities (Tables)	3 Months Ended
	Mar. 31, 2019
Investments Debt And Equity Securities [Abstract]
Schedule of Fair Value of Available-for-Sale Marketable Securities	As of March 31, 2019, the fair value of available-for-sale marketable securities by type of security was as follows: March 31, 2019 (In thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury Securities $ 8,969 $ — $ (3 ) $ 8,966 $ 8,969 $ — $ (3 ) $ 8,966 December 31, 2018 (In thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury Securities $ 18,424 $ — $ (11 ) $ 18,413 $ 18,424 $ — $ (11 ) $ 18,413

Property and Equipment (Tables)

Property and Equipment (Tables)	3 Months Ended
	Mar. 31, 2019
Property Plant And Equipment [Abstract]
Summary of Property and Equipment	Property and equipment as of March 31, 2019 and December 31, 2018 consisted of the following: March 31, 2019 December 31, 2018 (in thousands) Computer equipment $ 192 $ 182 Laboratory equipment 3,881 3,872 Furniture and fixtures 93 93 4,166 4,147 Less: Accumulated depreciation $ (1,571 ) $ (1,366 ) Total property and equipment, net $ 2,595 $ 2,781

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Schedule of Estimated Fair Value of Each Stock Option Award	For stock options requiring an assessment of value during the three months ended March 31, 2019, the fair value of each stock option award was estimated using the Black-Scholes option-pricing model utilizing the following assumptions: March 31, 2019 Risk-free interest rate 2.49 to 2.59% Expected dividend yield 0% Expected volatility 82.0-90.2% Expected life 4.0 to 6.25 years
Summary of Stock Option Activity	A summary of stock option activity for the three months ended March 31, 2019 is as follows: Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in Years) Stock options outstanding at December 31, 2018 4,540,321 $ 4.07 5.76 Granted 774,600 6.33 Exercised (85,793 ) — Cancelled (14,375 ) — Stock options outstanding at March 31, 2019 5,214,753 7.03 5.88 Stock options exercisable at March 31, 2019 1,912,524 $ 5.62 4.78
Schedule of Stock-Based Compensation Included in Statement of Operations	Stock-based compensation for the three months ended March 31, 2019 and 2018 was included in the statement of operations as follows: Three Months Ended March 31, (in thousands) 2019 2018 General and administrative $ 560 $ 380 Research and development 1,208 778 Total $ 1,768 $ 1,158

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
Schedule of Future Minimum Lease Payments for Operating Lease	Future minimum lease payments under these leases at March 31, 2019 are as follows: Year (in thousands) 2019 $ 2,842 2020 4,910 2021 1,432 Total lease payment $ 9,184 Less: present value discount (594 ) Total $ 8,590

Organization and Basis of Pre_2

Organization and Basis of Presentation - Additional Information (Details)	3 Months Ended
	Mar. 31, 2019USD ($)
Organization Consolidation And Presentation Of Financial Statements [Abstract]
State of incorporation	Delaware
Date of incorporation	Dec. 31, 2014
Cash, cash equivalents and marketable securities	$ 30,879,000

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Jan. 01, 2019	Dec. 31, 2018
Summary Of Significant Accounting Policies [Line Items]
Restricted cash used to collateralize a credit card	$ 150,000			$ 150,000
Acquired intangible asset, useful life	15 years
Disposals of property and equipment	$ 0	$ 0
Cash equivalents	21,913,385
Short-term marketable securities	8,966,250			18,413,000
Operating lease, right-of-use asset	8,691,000
Operating lease, liability	8,590,000
ASU 2016-02
Summary Of Significant Accounting Policies [Line Items]
Operating lease, right-of-use asset	8,691,000		$ 9,692,000
Operating lease, liability	8,590,000		$ 9,347,000
General and Administrative Expense
Summary Of Significant Accounting Policies [Line Items]
Patent expenses	$ 569,000	$ 117,000
Type of Cost, Good or Service [Extensible List]	us-gaap:LicenseMember	us-gaap:LicenseMember
Certificate of Deposit
Summary Of Significant Accounting Policies [Line Items]
Short-term restricted cash	$ 50,000			$ 50,000

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of Estimated Useful Lives of Assets (Details)	3 Months Ended
	Mar. 31, 2019
Laboratory Equipment
Property Plant And Equipment [Line Items]
Estimated useful lives	5 years
Computer and Office Equipment
Property Plant And Equipment [Line Items]
Estimated useful lives	3 years
Furniture and Fixtures | Minimum
Property Plant And Equipment [Line Items]
Estimated useful lives	3 years
Furniture and Fixtures | Maximum
Property Plant And Equipment [Line Items]
Estimated useful lives	8 years

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Schedule of Consolidated Balance Sheet as Impacted by the Present Value of Future Cash Flows Calculation Against Both Asset and Liability (Details) - USD ($)	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Operating Leased Assets [Line Items]
Deferred rent			$ (381,000)
Operating lease right-of-use	$ 8,691,000
Operating lease liability	(8,590,000)
ASU 2016-02
Operating Leased Assets [Line Items]
Operating lease right-of-use	8,691,000	$ 9,692,000
Operating lease liability	$ (8,590,000)	(9,347,000)
ASU 2016-02 | Adjustment
Operating Leased Assets [Line Items]
Deferred rent		381,000
Operating lease right-of-use		9,691,000
Operating lease liability		$ (9,346,000)

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Schedule of Anti-dilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	6,467,194	4,009,662
Common Stock Warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	1,252,441	1,252,441
Common Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	5,214,753	2,757,221

Fair Value - Schedule of Fair V

Fair Value - Schedule of Fair Value Assets Measured on Recurring Basis (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	$ 21,913,385
Marketable securities	8,966,250	$ 18,413,000
Total		28,960,000
Fair Value Measurements, Recurring Basis
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	16,176,000	10,548,000
Marketable securities	8,966,000	18,412,000
Total	25,142,000	28,960,000
Fair Value Measurements, Recurring Basis | Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	16,176,000	10,548,000
Total	16,176,000	10,548,000
Fair Value Measurements, Recurring Basis | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Marketable securities	8,966,000	18,412,000
Total	$ 8,966,000	$ 18,412,000

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair value assets transfers between Level 2 and Level 3	$ 0	$ 0
Cash equivalents and marketable securities		$ 28,960,000

Marketable Securities - Schedul

Marketable Securities - Schedule of Fair Value of Available-for-Sale Marketable Securities (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 8,969,000	$ 18,424,000
Gross Unrealized Losses	(3,000)	(11,000)
Fair Value	8,966,250	18,413,000
U.S. Treasury Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	8,969,000	18,424,000
Gross Unrealized Losses	(3,000)	(11,000)
Fair Value	$ 8,966,000	$ 18,413,000

Marketable Securities - Additio

Marketable Securities - Additional Information (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Investments Debt And Equity Securities [Abstract]
Marketable securities	$ 8,966,000	$ 18,413,000

Property and Equipment - Summar

Property and Equipment - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 4,166	$ 4,147
Less: Accumulated depreciation	(1,571)	(1,366)
Total property and equipment, net	2,595	2,781
Computer Equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	192	182
Laboratory Equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	3,881	3,872
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 93	$ 93

Property and Equipment - Additi

Property and Equipment - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Property Plant And Equipment [Abstract]
Depreciation expense	$ 205,000	$ 167,000
Disposals of property and equipment	$ 0	$ 0

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Estimated Fair Value of Each Stock Option Award (Details)	3 Months Ended
	Mar. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate, minimum	2.49%
Risk-free interest rate, maximum	2.59%
Expected dividend yield	0.00%
Expected volatility, minimum	82.00%
Expected volatility, maximum	90.20%
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected life	4 years
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected life	6 years 3 months

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity (Details) - $ / shares	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Roll Forward
Number of Shares, Outstanding Beginning Balance	4,540,321
Number of Shares, Granted	774,600
Number of Shares, Exercised	(85,793)
Number of Shares, Cancelled	(14,375)
Number of Shares, Outstanding Ending Balance	5,214,753	4,540,321
Number of Shares, Exercisable	1,912,524
Weighted Average Exercise Price, Outstanding Beginning Balance	$ 4.07
Weighted Average Exercise Price, Granted	6.33
Weighted Average Exercise Price, Outstanding Ending Balance	7.03	$ 4.07
Weighed Average Exercise Price, Exercisable	$ 5.62
Weighted Average Remaining Contractual Life (in Years)	5 years 10 months 17 days	5 years 9 months 3 days
Weighted Average Remaining Contractual Life (in Years), Exercisable	4 years 9 months 10 days

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) - USD ($)	Mar. 31, 2019	Mar. 29, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Unrecognized stock-based compensation	$ 16,123,087
Intrinsic value of exercisable stock options	$ 398,642
Intrinsic value of exercisable fair value per share		$ 7.73

Stock-Based Compensation - Sc_2

Stock-Based Compensation - Schedule of Stock-Based Compensation Included in Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	$ 1,768	$ 1,158
General and Administrative Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	560	380
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	$ 1,208	$ 778

Warrants - Additional Informati

Warrants - Additional Information (Details)	Mar. 29, 2019$ / shares	Mar. 31, 2019USD ($)Tranche$ / sharesshares	Jun. 15, 2015$ / shares
Class Of Warrant Or Right [Line Items]
Number of tranches | Tranche		2
First tranche
Class Of Warrant Or Right [Line Items]
Common stock warrants outstanding | shares		370,370
Exercise price of common stock warrants			$ 2.70
Common stock warrants life			7 years
Common stock warrants expiration date		Jun. 15, 2022
Warrant
Class Of Warrant Or Right [Line Items]
Intrinsic value of common stock warrants | $		$ 1,863,000
Fair value of common stock	$ 7.73
Second tranche
Class Of Warrant Or Right [Line Items]
Common stock warrants outstanding | shares		882,071
Exercise price of common stock warrants		$ 9.38
Common stock warrants life		5 years
Common stock warrants expiration date		Dec. 26, 2022

Revenue Recognition - Additiona

Revenue Recognition - Additional Information (Details1) - Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2019-04-01	Mar. 31, 2019
Current Liabilities | Maximum
Disaggregation Of Revenue [Line Items]
Revenue expected to be recognized	12 months
Current Liabilities | Maximum | Einstein | Einstein License And Service Agreement
Disaggregation Of Revenue [Line Items]
Revenue expected to be recognized	12 months
Contract Liabilities | Minimum
Disaggregation Of Revenue [Line Items]
Revenue expected to be recognized	12 months
Contract Liabilities | Minimum | Einstein | Einstein License And Service Agreement
Disaggregation Of Revenue [Line Items]
Revenue expected to be recognized	12 months

Revenue Recognition - Additio_2

Revenue Recognition - Additional Information (Details) - USD ($)	Nov. 06, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Disaggregation Of Revenue [Line Items]
Transaction price recorded in liabilities		$ 2,500,000
Collaboration revenue		370,000
Short-term research and development contract liability		1,887,000		$ 2,012,000
Long-term research and development contract liability		4,930,000		5,175,000
Prepaid expenses and other short-term assets		1,039,000		1,347,000
Other long-term assets		771,000		809,000
Merck | Collaboration Agreement with Merck
Disaggregation Of Revenue [Line Items]
Collaboration revenue		370,000	$ 0
Short-term research and development contract liability		893,157
Long-term research and development contract liability		94,160
LG Chem Life Sciences | Collaboration Agreement with LG Chem Life Sciences
Disaggregation Of Revenue [Line Items]
Collaboration revenue		0
Equity investment nonrefundable upfront cash payment	$ 5,000,000
Equity investment for research collaboration agreement	5,000,000
Additional amount receivable research development regulatory and sales milestones	400,000,000
Upfront payment associated with contract liability	5,000,000
Income tax expense	825,000
Premium paid for stock purchased	829,000
LG Chem Life Sciences | Collaboration Agreement with LG Chem Life Sciences | Maximum
Disaggregation Of Revenue [Line Items]
Additional amount receivable research development regulatory and sales milestones	$ 400,000,000
Einstein | Einstein License And Service Agreement
Disaggregation Of Revenue [Line Items]
Transaction price recorded in liabilities		5,800,000
Collaboration revenue		0
Short-term research and development contract liability		993,396
Long-term research and development contract liability		4,835,958
License expenses		36,494		$ 438,000
Prepaid expenses and other short-term assets		54,200
Other long-term assets		$ 347,235

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Details) - Chief Financial Officer - MDB - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Related Party Transaction [Line Items]
Monthly compensation payable to officer	$ 6,000
Aggregate compensation payable to officer	$ 0	$ 18,000

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details)

Sep. 20, 2018USD ($)

Jun. 18, 2018

Jan. 18, 2018USD ($)

Jan. 16, 2018

Nov. 14, 2017USD ($)

Jul. 01, 2017

Dec. 01, 2016

Mar. 31, 2019USD ($)

Mar. 31, 2018USD ($)

Dec. 31, 2019USD ($)

Nov. 06, 2018USD ($)

Dec. 31, 2015SupportingTechnology

Commitments And Contingencies [Line Items]

Collaboration revenue

$ 370,000

Operating lease right-of-use

8,691,000

Rent expense

1,137,000

$ 670,000

Amended Lease Agreement

Commitments And Contingencies [Line Items]

Lease agreement effective date

May 15, 2018

Jan. 16, 2018

Jul. 1, 2017

Dec. 1, 2016

Lease expiration date

Apr. 14, 2021

Apr. 30, 2018

Operating Lease Agreement

Commitments And Contingencies [Line Items]

Lease agreement effective date

Oct. 15, 2018

Lease expiration date

Apr. 14, 2021

Apr. 30, 2021

Lessee operating lease monthly rental rate for first eighteen months

$ 297,500

Lessee operating lease monthly rental payments for remaining term

$ 78,600

$ 330,500

Lessee operating lease monthly rental payments for first twelve months

$ 72,600

Operating lease deposit amount

236,000

Operating lease right-of-use

727,000

Albert Einstein College Of Medicine | Einstein License And Service Agreement

Commitments And Contingencies [Line Items]

Milestone payments for each product, process or service

1,850,000

Milestone payments for each new indication of licensed product

1,850,000

Aggregate amount of additional milestone payments

5,750,000

Catalent | Agreements with Catalent | Services on Development and Manufacture of Lead Drug Candidate

Commitments And Contingencies [Line Items]

Total direct costs under agreement

$ 600,000

Estimated additional direct costs under agreement

$ 200,000

Anticipated contracted services to be received, period from date of payment

12 months

Merck | Collaboration Agreement with Merck

Commitments And Contingencies [Line Items]

Up front non refundable payment

$ 2,500,000

Achievement of certain research and development milestones

120,000,000

Achievement of certain commercial milestones

150,000,000

Milestone payments received

2,500,000

Collaboration revenue

$ 370,000

0

Merck | Collaboration Agreement with Merck | Maximum

Commitments And Contingencies [Line Items]

Eligible to earn achievement of certain research and development milestones

$ 101,000,000

LG Chem Life Sciences | Collaboration Agreement with LG Chem Life Sciences

Commitments And Contingencies [Line Items]

Collaboration revenue

0

Equity investment nonrefundable upfront cash payment

$ 5,000,000

Equity investment for research collaboration agreement

5,000,000

Additional amount receivable research development regulatory and sales milestones

400,000,000

LG Chem Life Sciences | Collaboration Agreement with LG Chem Life Sciences | Maximum

Commitments And Contingencies [Line Items]

Additional amount receivable research development regulatory and sales milestones

$ 400,000,000

Einstein License

Commitments And Contingencies [Line Items]

Number of supporting technologies | SupportingTechnology

2

Patent expenses

$ 12,500

$ 10,000

Type of Cost, Good or Service [Extensible List]

us-gaap:LicenseMember

us-gaap:LicenseMember

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Future Minimum Lease Payments on Operating Leases (Details) $ in Thousands	Mar. 31, 2019USD ($)
Commitments And Contingencies Disclosure [Abstract]
2019	$ 2,842
2020	4,910
2021	1,432
Total lease payment	9,184
Less: present value discount	(594)
Total	$ 8,590