Kineta (KANT) 10-K 31 Mar 21 2020 FY Annual report Financial data

Cover Page

Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2020	Mar. 19, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity File Number	001-38549
Entity Registrant Name	YUMANITY THERAPEUTICS, INC.
Entity Central Index Key	0001445283
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No
Title of 12(b) Security	Common Stock, par value $0.001
Trading Symbol	YMTX
Security Exchange Name	NASDAQ
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-8436652
Document Annual Report	true
Document Transition Report	false
Entity Address, Address Line One	40 Guest Street
Entity Address, Address Line Two	Suite 4410
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02135
City Area Code	617
Local Phone Number	409-5300
Entity Public Float			$ 60,454,412
Entity Common Stock, Shares Outstanding		10,193,831
Documents Incorporated by Reference	Portions of the registrant’s Proxy Statement for its 2021 Annual Meeting of Stockholders, which the registrant intends to file with the Securities and Exchange Commission not later than 120 days after the registrant’s fiscal year ended December 31, 2020, are incorporated by reference into Part III of this Annual Report on Form 10-K.
ICFR Auditor Attestation Flag	false

Consolidated Balance sheets

Consolidated Balance sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 80,819	$ 14,021
Marketable securities	4,498	1,347
Prepaid expenses and other current assets	2,264	681
Restricted cash		125
Total current assets	87,581	16,174
Property and equipment, net	874	1,017
Operating lease right-of-use assets	23,678	275
Deposits	386	40
Restricted cash	2,066	100
Assets held-for-sale	250
Total assets	114,835	17,606
Current liabilities:
Accounts payable	7,384	1,905
Accrued expenses and other current liabilities	7,851	2,421
Current portion of long-term debt	2,891	0
Operating lease liabilities	4,468	291
Current portion of finance lease obligation	166	343
Deferred revenue	8,104
Total current liabilities	30,864	4,960
Long-term debt, net of discount and current portion	13,237	14,470
Operating lease liabilities, net of current portion	14,479
Finance lease obligation, net of current portion	48	116
Preferred unit warrant liability	0	261
Total liabilities	58,628	19,807
Commitments and contingencies (Note 16)
Stockholders' equity/Members' deficit:
Preferred stock, $0.001 par value; 5,000,000 shares and no shares authorized at December 31, 2020 and 2019, respectively; no shares issued and outstanding as of December 31, 2020 and 2019
Common stock, $0.001 par value; 125,000,000 shares and no shares authorized at December 31, 2020 and 2019, respectively; 10,193,831 shares and no shares issued and outstanding as of December 31, 2020 and 2019, respectively	10
Additional paid-in capital	204,007
Accumulated deficit	(147,810)	(97,020)
Total stockholders' equity/members' deficit	56,207	(91,900)
Total liabilities, preferred units and stockholders' equity/ members' deficit	$ 114,835	17,606
Preferred Units [Member]
Current liabilities:
Preferred units (Class A, B and C), no units and 17,515,738 units authorized at December 31, 2020 and 2019, respectively; no units and 12,391,101 units issued and outstanding at December 31, 2020 and 2019, respectively		89,699
Stockholders' equity/Members' deficit:
Total stockholders' equity/members' deficit		89,699
Common Units [Member]
Stockholders' equity/Members' deficit:
Common units, no units and 15,492,000 units authorized at December 31, 2020 and 2019, respectively; no units and 2,163,099 units issued and outstanding at December 31, 2020 and 2019, respectively		5,120
Total stockholders' equity/members' deficit		$ 5,120

Consolidated Balance sheets (Pa

Consolidated Balance sheets (Parenthetical) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	0
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	125,000,000	0
Common stock, shares issued	10,193,831	0
Common stock, shares outstanding	10,193,831	0
Preferred Units [Member]
Preferred units, Authorized	0	17,515,738
Preferred units, Issued	0	12,391,101
Preferred units, Outstanding	0	12,391,101
Common Units [Member]
Common units, Authorized	0	15,492,000
Common units, Issued	0	2,163,099
Common units, Outstanding	0	2,163,099

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Statement [Abstract]
Collaboration revenue	$ 6,896
Operating expenses:
Research and development	22,310	$ 22,969
General and administrative	11,881	7,062
In-process research and development assets acquired	28,336
Total operating expenses	62,527	30,031
Loss from operations	(55,631)	(30,031)
Other income (expense):
Change in fair value of preferred unit warrant liability	72	12
Interest Expense	(1,900)	(1,209)
Interest income and other income (expense), net	(28)	530
Loss on debt extinguishment		(511)
Total other expense, net	(1,856)	(1,178)
Net loss	(57,487)	(31,209)
Gain on extinguishment of Class B preferred units	6,697
Net loss applicable to common shareholders	$ (50,790)	$ (31,209)
Net loss per share/unit, basic and diluted	$ (21.57)	$ (14.71)
Weighted average common shares/units outstanding, basic and diluted	2,354,143	2,121,843

Consolidated Statement of Compr

Consolidated Statement of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (57,487)	$ (31,209)
Other comprehensive income:
Unrealized gains on marketable securities, net of tax of $0	0	8
Comprehensive loss	$ (57,487)	$ (31,201)

Consolidated Statement of Com_2

Consolidated Statement of Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Unrealized gain on marketable securities, net of tax	$ 0	$ 0

Consolidated Statements of Pref

Consolidated Statements of Preferred Units and Stockholders' Equity/Members' Deficit - USD ($) $ in Thousands	Total	Merger [Member]	Preferred Units [Member]	Common Units [Member]	Common Stock [Member]	Common Stock [Member]Merger [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member]Merger [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated Deficit [Member]	Yumanity Holdings LLC [Member]	Yumanity Holdings LLC [Member]Preferred Units [Member]	Yumanity Holdings LLC [Member]Common Units [Member]	Yumanity Holdings LLC [Member]Defaulting Class B Preferred Units [Member]	Yumanity Holdings LLC [Member]Common Stock [Member]	Yumanity Holdings LLC [Member]Additional Paid-in Capital [Member]	Class C Preferred Units [Member]Preferred Units [Member]	Class B Preferred Units [Member]	Class B Preferred Units [Member]Preferred Units [Member]	Class B Preferred Units [Member]Defaulting Class B Preferred Units [Member]	Class B Preferred Units [Member]Accumulated Deficit [Member]
Beginning balance at Dec. 31, 2018	$ (62,244)		$ 89,699	$ 3,575					$ (8)	$ (65,811)
Beginning balance, shares at Dec. 31, 2018			12,391,101	2,167,179
Forfeiture of unvested incentive units, shares				(4,080)
Stock/equity-based compensation expense	1,545			$ 1,545
Unrealized gains on marketable securities	8								$ 8
Gain on extinguishment of Ordinary Class B preferred units																		$ 0
Net loss	(31,209)									(31,209)
Ending balance at Dec. 31, 2019	(91,900)		$ 89,699	$ 5,120						(97,020)
Ending balance, shares at Dec. 31, 2019			12,391,101	2,163,099
Forfeiture of unvested incentive units, shares				(790)
Stock/equity-based compensation expense	2,266			$ 2,266
Gain on extinguishment of Ordinary Class B preferred units																		6,697	$ (6,697)		$ 6,697
Exchange of common stock in connection with the Merger		$ 60,130				$ 3		$ 60,127
Exchange of common stock in connection with the Merger, shares						2,708,537
Fair value of replacement equity	471						$ 471
Reclassification of warrant liability to permanent equity	189						189
Issuance of common stock, net of issuance costs																	$ 21,235
Issuance of common stock, net of issuance costs, shares																	5,404,588
Exchange of Units, Value											$ 103,949				$ 4	$ 104,233
Exchange of Units, Number															3,745,983
Exchange of Units, Value												$ (103,949)		$ (288)
Exchange of Units, Number												(16,959,370)		(836,319)
Exchange of Units, Number													(2,162,309)		2,278,450				(836,319)	836,319
Exchange of Units, Value													$ (7,386)		$ 2	$ 7,384		$ 288	$ (288)	$ 288
Private placement of common stock for payment of consulting services	31,604				$ 1		31,603
Private placement of common stock for payment of consulting services, shares					1,460,861
Net loss	(57,487)									(57,487)
Ending balance at Dec. 31, 2020	$ 56,207				$ 10		$ 204,007			$ (147,810)
Ending balance, shares at Dec. 31, 2020					10,193,831

Consolidated Statements of Pr_2

Consolidated Statements of Preferred Units and Stockholders' Equity/Members' Deficit (Parenthetical) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Class C Preferred Units [Member]
Stock Issuance Costs	$ 388
Common Stock [Member]
Stock Issuance Costs	$ 1,996

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net loss	$ (57,487)	$ (31,209)
Adjustments to reconcile net loss to net cash used in operating activities:
Non-cash expense for in-process research and development acquired	28,336
Depreciation and amortization expense	770	1,057
Non-cash lease expense	2,501	1,049
Stock/equity-based compensation expense	2,266	1,545
Accretion of discounts on marketable securities	(6)	(316)
Non-cash interest expense	535	318
Loss on debt extinguishment		511
Change in fair value of preferred unit warrant liability	(72)	(12)
Gain on sale of property and equipment	(2)
Loss on disposal of property and equipment		3
Changes in operating assets and liabilities, excluding the effect of acquisition:
Prepaid expenses and other current assets	(1,497)	(418)
Deposits	(346)	75
Operating lease liabilities	(1,688)	(986)
Accounts payable	2,802	533
Accrued expenses and other current liabilities	(2,154)	642
Deferred revenue	8,104
Net cash used in operating activities	(17,938)	(27,208)
Cash flows from investing activities:
Purchases of marketable securities	(4,495)	(19,347)
Proceeds from sales and maturities of marketable securities	1,350	53,235
Purchases of property and equipment	(246)	(638)
Proceeds from sale of property and equipment	13
Cash, cash equivalents, and restricted cash acquired in connection with the Merger	35,939
Merger transaction costs	(1,520)
Net cash provided by investing activities	31,041	33,250
Cash flows from financing activities:
Proceeds from private placement of common stock, net of issuance costs	33,597
Proceeds from Paycheck Protection Program loan	1,123
Proceeds from issuance of long-term debt, net of issuance costs		14,750
Repayments of long-term debt		(10,767)
Payments of prior-year issuance costs related to long-term debt	(72)
Payments of finance lease obligations	(347)	(958)
Net cash provided by financing activities	55,536	3,025
Net increase in cash, cash equivalents and restricted cash	68,639	9,067
Cash, cash equivalents and restricted cash at beginning of period	14,246	5,179
Cash, cash equivalents and restricted cash at end of period	82,885	14,246
Supplemental cash flow information:
Cash paid for interest	1,287	910
Supplemental disclosure of noncash investing and financing activities:
Additions to property and equipment under finance lease	102
Issuance of preferred unit warrant in connection with loan		223
Deferred financing costs included in accounts payable		72
Merger transaction costs included in accounts payable and accrued expenses	1,169
Offering costs included in accounts payable	1,993
Operating lease liabilities arising from obtaining right-of-use assets	10,219	$ 469
Fair value of net assets acquired in the Merger, excluding cash, cash equivalents and restricted cash acquired	24,662
Conversion of preferred units to common stock	104,237
Conversion of preferred unit warrants into common stock warrants	189
Class C Preferred Units [Member]
Cash flows from financing activities:
Proceeds from issuance of Class C preferred units, net of offering costs paid	$ 21,235

Nature of Business and Basis of

Nature of Business and Basis of Presentation	12 Months Ended
	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business and Basis of Presentation	1. Nature of Business and Basis of Presentation Yumanity Therapeutics, Inc. (formerly Proteostasis Therapeutics, Inc., and together with its wholly owned subsidiary, the “Company” or “Yumanity”) is a clinical stage biopharmaceutical company engaged in the research and development of treatments for neurodegenerative diseases caused by protein misfolding. The Company is subject to risks similar to those of other early clinical stage companies in the biopharmaceutical industry, including dependence on key individuals, the need to develop commercially viable products, competition from other companies, many of whom are larger and better capitalized, the impact of the COVID-19 Merger with Proteostasis Therapeutics, Inc. On December 22, 2020, Proteostasis Therapeutics, Inc. (“Proteostasis” or “PTI”) completed its previously announced merger transaction with Yumanity, Inc. (formerly Yumanity Therapeutics, Inc.) in accordance with the terms of the Agreement and Plan of Merger and Reorganization, dated as of August 22, 2020, as amended on November 6, 2020 (the “Merger Agreement”), by and among Pangolin Merger Sub, Inc., a wholly-owned subsidiary of Proteostasis (“Merger Sub”), Yumanity Holdings, LLC (“Holdings”) and Yumanity, Inc., pursuant to which Merger Sub merged with and into Yumanity, Inc., with Yumanity, Inc. surviving as a wholly owned subsidiary of Proteostasis (the “Merger”). Immediately prior to the effective time of the Merger, Holdings merged with and into Yumanity, Inc. and Yumanity, Inc. continued to exist as the surviving corporation. On December 22, 2020, in connection with, and prior to the completion of, the Merger, Proteostasis effected a 1-for-20 At the effective time of the Merger (the “Effective Time”), each share of Yumanity Inc.’s common stock, par value $0.01 (the “Yumanity Common Stock”), outstanding immediately prior to the Effective Time was converted into the right to receive shares of PTI based on an exchange ratio set forth in the Merger Agreement. At the Effective Time following the Reverse Stock Split, the exchange ratio was determined to be 0.2108 shares of PTI Common Stock for each share of Yumanity Common Stock (the “Exchange Ratio”). At the closing of the Merger on December 22, 2020, PTI issued an aggregate of 6,024,433 shares of its common stock to Yumanity, based on the Exchange Ratio. In addition, all options and warrants exercisable for shares of common stock of Yumanity, Inc. became options and warrants exercisable for shares of common stock of PTI equal to the Exchange Ratio multiplied by the number of shares of Yumanity Inc.’s common stock previously represented by such stock options and warrants, as applicable, with a proportionate adjustment in exercise price. No fractional shares were issued in connection with the Exchange Ratio. The transaction was accounted for as a reverse merger and as an asset acquisition in accordance with GAAP. Under this method of accounting, Yumanity was deemed to be the accounting acquirer for financial reporting purposes. This determination was primarily based on the fact that, immediately following the Merger: (i) Yumanity’s equityholders own a majority of the voting rights in the combined organization, (ii) Yumanity designated a majority of the members (7 of 9) of the initial board of directors of the combined organization and (iii) Yumanity’s senior management hold all key positions in the senior management of the combined organization. Accordingly, for accounting purposes, (i) the Merger was treated as the equivalent of the Yumanity issuing stock to acquire the net assets of PTI, (ii) the net assets of PTI were allocated a portion of the transaction price and recorded based upon their relative fair values in the financial statements at the time of closing, (iii) the reported historical operating results of the combined organization prior to the Merger will be those of Yumanity and (iv) for periods prior to the transaction, shareholders’ equity of the combined organization is presented based on the historical equity structure of Yumanity. As a result, as of the closing date of the Merger, the net assets of PTI were recorded at their acquisition-date fair values in the financial statements of Yumanity and the reported operating results prior to the Merger will be those of Yumanity. As used herein, the words “the Company” refer to, for periods following the Merger, Yumanity Therapeutics, Inc., together with its wholly owned subsidiary, and for periods prior to the Merger, Holdings, and its wholly owned subsidiary, as applicable. The Yumanity Reorganization On December 22, 2020, immediately prior to the closing of the Merger, pursuant to the terms of the Merger Agreement, the Company completed the Yumanity Reorganization whereby Holdings, the sole stockholder and holding company parent of Yumanity, Inc., merged with and into Yumanity, Inc., with Yumanity, Inc. as the surviving corporation. In connection with the Yumanity Reorganization, each outstanding common unit of Holdings was exchanged for shares of common stock of Yumanity, Inc. based upon a ratio associated with the terms of each common unit, each outstanding preferred unit of Holdings was converted into shares of common stock of Yumanity, Inc. based upon the ratio associated with each individual series of preferred units, each outstanding option to purchase shares of common units of Holdings was converted into an outstanding option to purchase shares of common stock of Yumanity, Inc. on a 1-for-1 1-for-1 Basis of presentation The Company’s consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”). The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiary. All intercompany accounts and transactions have been eliminated in consolidation. Unless otherwise noted, all references to common stock/unit share and per share amounts have also been adjusted to reflect the Exchange Ratio. Reverse Stock Split/Exchange Ratio All common shares/units and per common share/unit amounts for all periods presented in the accompanying consolidated financial statements and notes thereto have been adjusted retroactively, where applicable, to reflect the Exchange Ratio (0.2108). All PTI common stock amounts have been adjusted retroactively, where applicable, to reflect the 1-for-20 reverse stock split (“Reverse Stock Split”). Going concern The Company has evaluated whether there are certain conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the original issuance date of the consolidated financial statements. Since its inception, the Company has funded its operations primarily with proceeds from sales of preferred units and debt financings. In December 2020, the Company completed the Merger and a concurrent private placement of an aggregate of 1,460,861 shares of its common stock. The Company has incurred recurring losses and negative cash flows from operations since inception, including net losses of $57.5 million and $31.2 million for the years ended December 31, 2020 and 2019, respectively. In addition, as of December 31, 2020, the Company had an accumulated deficit of $147.8 million. The Company expects to continue to generate operating losses for the foreseeable future. As of March 31, 2021, the original issuance date of the consolidated financial statements for the year ended December 31, 2020, the Company expects that its cash, cash equivalents and marketable securities will fund its operating expenses, capital expenditure requirements and debt service payments into the third quarter of 2022. The Company will require additional financing to fund operations and plans to obtain additional funding through private or public equity financings, debt financings, or other capital sources, including collaborations with other companies or other strategic transactions. There is no assurance that the Company will be successful in obtaining sufficient funding on terms acceptable to the Company to fund continuing operations, if at all. If the Company is unable to obtain additional funding, the Company will be forced to delay, reduce or eliminate some or all of its research and development programs, product portfolio expansion or commercialization efforts, which could adversely affect its business prospects, or the Company may be unable to continue operations. Impact of the COVID-19 The COVID-19 COVID-19 The Company is monitoring the potential impact of the COVID-19 COVID-19 COVID-19,

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Use of estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting periods. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, revenue recognition, the accrual of research and development expenses, the valuation of common units prior to the Merger and the valuation of stock/unit-based awards. The Company bases its estimates on historical experience, known trends and other market-specific or other relevant factors that it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates as there are changes in circumstances, facts, and experience. Actual results may differ from those estimates or assumptions. Segment information The Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions. All of the Company’s tangible assets are held in the United States. Concentrations of credit risk and of significant suppliers Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents and marketable securities. At times the Company may maintain cash and investment balances in excess of federally insured limits. The Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. The Company relies, and expects to continue to rely, on a small number of vendors to provide services, supplies and materials related to its discovery programs. These programs could be adversely affected by a significant interruption in these services or the availability of materials. Deferred financing costs The Company capitalizes certain legal and other third-party fees that are directly associated with obtaining access to capital under credit facilities. Deferred financing costs incurred in connection with obtaining access to capital are recorded in prepaid expenses and other current assets and are amortized over the term of the credit facility. Deferred financing costs related to a recognized debt liability are recorded as a reduction of the carrying amount of the debt liability and amortized to interest expense using the effective interest method over the repayment term. Cash equivalents The Company considers all highly liquid investments with original maturities of three months or less at the date of purchase to be cash equivalents. Restricted cash Amounts included in restricted cash represent amounts pledged as collateral for letters of credit required for a security deposit on the Company’s leased facilities, which was returned to the Company in August 2020, as well as amounts pledged as collateral for Company credit cards as part of the terms of the “New Loan” (see Note 8). These amounts are classified as restricted cash (current) and restricted cash (non-current), respectively, (non-current) Property and equipment Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation and amortization expense is recognized using the straight-line method over the estimated useful life of each asset as follows: Estimated Useful Life Laboratory equipment 2 - 3 years Office equipment, computers and software 2 - 5 years Furniture and fixtures 2 - 7 years Leasehold improvements Shorter of remaining term of lease or useful life Costs for capital assets not yet placed into service are capitalized as construction-in-progress and Assets held-for-sale The Company classifies assets as held-for-sale held-for-sale held-for-sale. Impairment of long-lived assets The Company evaluates its long-lived assets, which consist primarily of property and equipment and right-of-use Acquisitions Acquisitions of assets or a group of assets that do not meet the definition of a business are accounted for as asset acquisitions using the cost accumulation method, whereby the cost of the acquisition, including certain transaction costs, is allocated to the assets acquired on the basis of relative fair values. No goodwill is recognized in an asset acquisition. Intangible assets that are acquired in an asset acquisition for use in research and development activities which have an alternative future use are capitalized as in-process Fair value measurements Certain assets and liabilities are carried at fair value under GAAP. 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. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: • Level 1 — Quoted prices in active markets for identical assets or liabilities. • Level 2 — Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. • Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques. The Company’s cash equivalents and marketable securities are carried at fair value, determined according to the fair value hierarchy described above (see Note 4). The carrying values of the Company’s accounts payable and accrued expenses approximate their fair values due to the short-term nature of these liabilities. The carrying value of the Company’s long-term debt under its loan and security agreement approximates its fair value due to its variable interest rate. Marketable securities The Company’s marketable securities, which consist of debt securities, are classified as available-for-sale and The Company conducts periodic reviews to identify and evaluate each investment in the Company’s portfolio that has an unrealized loss to determine whether a credit loss exists. An unrealized loss exists when the current fair value of an individual security is less than its amortized cost basis. A credit loss is estimated by considering available information relevant to the collectability of the security and information about past events, current conditions, and reasonable and supportable forecasts. Any credit loss is recorded as a charge to other income (expense), net, not to exceed the amount of the unrealized loss. Unrealized losses other than the credit loss are recognized in accumulated other comprehensive income (loss). When determining whether a credit loss exists, the Company considers several factors, including whether the Company has the intent to sell the security or whether it is more likely than not that the Company will be required to sell the security prior to recovery of its amortized cost basis. If the Company has an intent to sell, or if it is more likely than not that the Company will be required to sell a debt security in an unrealized loss position before recovery of its amortized cost basis, the Company will write down the security to its fair value and record the corresponding charge as a component of other income (expense), net. No declines in value were deemed to be credit losses or other than temporary during the year ended December 31, 2020. Revenue recognition The Company accounts for its one collaboration arrangement, entered into in June 2020, under ASC Topic 606, Revenue From Contracts With Customers (ASC 606). For additional information on the Company’s collaboration agreement, see Note 6, Collaboration Agreement, to these consolidated financial statements. Under ASC 606, an entity recognizes revenue when its customer obtains control of promised goods or services in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements within the scope of ASC 606, the entity performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price, including variable consideration, if any; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company only applies the five-step model to contracts when it is probable that the entity will collect the consideration to which it is entitled in exchange for the goods or services it transfers to the customer. The Company assesses the goods or services promised within each contract and determines those that are performance obligations. Arrangements that include rights to additional goods or services that are exercisable at a customer’s discretion are generally considered options. The Company assesses if these options provide a material right to the customer and if so, they are considered performance obligations. The identification of material rights requires judgments related to the determination of the value of the underlying license relative to the option exercise price, including assumptions about technical feasibility and the probability of developing a candidate that would be subject to the option rights. The exercise of a material right is accounted for as a contract modification for accounting purposes. The Company assesses whether each promised good or service is distinct for the purpose of identifying the performance obligations in the contract. This assessment involves subjective determinations and requires management to make judgments about the individual promised goods or services and whether such are separable from the other aspects of the contractual relationship. Promised goods and services are considered distinct provided that: (i) the customer can benefit from the good or service either on its own or together with other resources that are readily available to the customer (that is, the good or service is capable of being distinct) and (ii) the entity’s promise to transfer the good or service to the customer is separately identifiable from other promises in the contract (that is, the promise to transfer the good or service is distinct within the context of the contract). In assessing whether a promised good or service is distinct, the Company considers factors such as the research, manufacturing and commercialization capabilities of the collaboration partner and the availability of the associated expertise in the general marketplace. The Company also considers the intended benefit of the contract in assessing whether a promised good or service is separately identifiable from other promises in the contract. If a promised good or service is not distinct, an entity is required to combine that good or service with other promised goods or services until it identifies a bundle of goods or services that is distinct. The transaction price is then determined and allocated to the identified performance obligations in proportion to their standalone selling prices (“SSP”) on a relative SSP basis. SSP is determined at contract inception and is not updated to reflect changes between contract inception and when the performance obligations are satisfied. Determining the SSP for performance obligations requires significant judgment. In developing the SSP for a performance obligation, the Company considers applicable market conditions and relevant entity- specific factors, including factors that were contemplated in negotiating the agreement with the customer and estimated costs. The Company validates the SSP for performance obligations by evaluating whether changes in the key assumptions used to determine the SSP will have a significant effect on the allocation of arrangement consideration between multiple performance obligations. If the consideration promised in a contract includes a variable amount, the Company estimates the amount of consideration to which it will be entitled in exchange for transferring the promised goods or services to a customer. The Company determines the amount of variable consideration by using the expected value method or the most likely amount method. The Company includes the unconstrained amount of estimated variable consideration in the transaction price. The amount included in the transaction price is constrained to the amount for which it is probable that a significant reversal of cumulative revenue recognized will not occur. At the end of each subsequent reporting period, the Company re-evaluates the cumulative catch-up basis If an arrangement includes development and regulatory milestone payments, the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the Company’s control or the licensee’s control, such as regulatory approvals, are generally not considered probable of being achieved until those approvals are received. For arrangements with licenses of intellectual property that include sales-based royalties, including milestone payments based on the level of sales, and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes royalty revenue and sales-based milestones at the later of (i) when the related sales occur, or (ii) when the performance obligation to which the royalty has been allocated has been satisfied. The Company records amounts as accounts receivable when the right to consideration is deemed unconditional. When consideration is received, or such consideration is unconditionally due, from a customer prior to transferring goods or services to the customer under the terms of a contract, a contract liability is recorded for deferred revenue. In determining the transaction price, the Company adjusts consideration for the effects of the time value of money if the timing of payments provides the Company with a significant benefit of financing. The Company does not assess whether a contract has a significant financing component if the expectation at contract inception is such that the period between payment by the licensees and the transfer of the promised goods or services to the licensees will be one year or less. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) each performance obligation is satisfied, either at a point in time or over time, and if over time, recognition is based on the use of an output or input method. Classification and accretion of preferred units The Company’s preferred units were classified outside of members’ deficit on the consolidated balance sheets because the holders of such units had redemption rights in the event of a deemed liquidation that, in certain situations, were not solely within the control of the Company. The occurrence of a deemed liquidation event was not determined to be probable in any period prior to the Merger, therefore the carrying values of the preferred units were not being accreted to their redemption values. Research and development costs Costs for research and development activities are expensed in the period in which they are incurred. Research and development expenses consist of costs incurred in performing research and development activities, including salaries and bonuses, stock/equity-based compensation, employee benefits, facilities costs, laboratory supplies, depreciation and amortization, manufacturing expenses, and external costs of vendors engaged to conduct research and preclinical development activities and clinical trials as well as the cost of licensing technology. Upfront payments under license agreements are expensed upon receipt of the license, and annual maintenance fees under license agreements are expensed in the period in which they are incurred. Milestone payments under license agreements are accrued, with a corresponding expense being recognized, in the period in which the milestone is determined to be probable of achievement and the related amount is reasonably estimable. Non - Research, development, and manufacturing contract costs and accruals The Company has entered into various research, development, and manufacturing contracts with research institutions and other companies. These agreements are generally cancelable, and related costs are recorded as research and development expenses as incurred. The Company records accruals for estimated ongoing research and development costs. When billing terms under these contracts do not coincide with the timing of when the work is performed, the Company is required to make estimates of outstanding obligations to those third parties as of period end. Any accrual estimates are based on a number of factors, including the Company’s knowledge of the progress towards completion of the research, development, and manufacturing activities, invoicing to date under the contracts, communication from the research institutions and other companies of any actual costs incurred during the period that have not yet been invoiced, and the costs included in the contracts. Significant judgments and estimates may be made in determining the accrued balances at the end of any reporting period. Actual results could differ from the estimates made by the Company. The historical accrual estimates made by the Company have not been materially different from the actual costs. Patent costs All patent-related costs incurred in connection with filing and prosecuting patent applications are expensed as incurred due to the uncertainty about the recovery of the expenditure. Amounts incurred are classified as general and administrative expenses. Stock/equity-based compensation The Company measures awards with service-based vesting or performance-based vesting granted to employees, non-employees and for non-employees, both The Company classifies stock/equity-based compensation expense in its consolidated statements of operations in the same manner in which the award recipient’s payroll costs are classified or in which the award recipient’s service payments are classified. Income taxes Prior to the Yumanity Reorganization, Holdings was organized as a Limited Liability Company and subject to the provisions of Subchapter K of the Internal Revenue Code. As such, Holdings was not viewed as a taxpaying entity in any jurisdiction and did not require a provision for income taxes. Each member was responsible for the tax liability, if any, related to its proportionate share of the member’s taxable income. The Company’s wholly owned corporate subsidiary was a taxpaying entity. After the Yumanity Reorganization, the Company and its subsidiary are both taxpaying entities. The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or in the Company’s tax returns. Deferred tax assets and liabilities are determined on the basis of the differences between the financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. Potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits expected and considering prudent and feasible tax planning strategies. The Company accounts for uncertainty in income taxes recognized in the consolidated financial statements by applying a two-step process deemed more-likely-than-not to Comprehensive loss Comprehensive loss includes net loss as well as other changes in stockholders’ equity/members’ deficit that result from transactions and economic events other than those with its members. The Company’s only elements of other comprehensive loss are unrealized gains (losses) on marketable securities. Net loss per share Basic net income (loss) per common share is computed by dividing the net income (loss) by the weighted average number of shares of common stock outstanding for the period. Diluted net income (loss) per common share is computed by dividing net income (loss) by the weighted average number of common shares outstanding for the period, including potential dilutive common shares assuming the dilutive effect of outstanding common stock equivalents. For periods in which the Company reported a net loss, diluted net loss per common share is the same as basic net loss per common share, since dilutive common shares are not assumed to have been issued if their affect is anti-dilutive. Leases In accordance with ASC 842, the Company determines at the inception of a contract if such arrangement is or contains a lease. A contract is or contains a lease if the contract conveys the right to control the use of an identified asset for a period of time in exchange for consideration. The Company classifies leases at the lease commencement date as operating or finance leases and records a right-of-use asset The Company often enters into contracts that contain both lease and non-lease components. Non-lease components and non-lease components of right-of-use assets Lease liabilities and their corresponding right-of-use assets Certain of the Company’s leases include options to extend or terminate the lease. The amounts determined for the Company’s right-of-use assets Recently adopted accounting pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial (“ASU 2016-13”), which ASU 2016-13 replaces to available-for-sale debt ASU No. 2018-19, Codification for non-public entities ASU 2016-13. The ASU No. 2019-05, Financial (“ASU 2019-05”). ASU 2019-05 provides ASU 2016-13 is Recently issued accounting pronouncements In December 2019, the FASB issued ASU No. 2019-12 ,

Merger Accounting

Merger Accounting	12 Months Ended
	Dec. 31, 2020
Business Combinations [Abstract]
Merger Accounting	3. Merger Accounting On December 22, 2020, the Company completed its merger with PTI. Based on the Exchange Ratio, immediately following the Merger, former PTI stockholders, PTI option holders and other persons holding securities or other rights directly or indirectly convertible, exercisable or exchangeable for PTI Common Stock owned approximately 29.7% of the outstanding capital stock of the combined organization, and the former Yumanity stockholders, Yumanity option holders and other persons holding securities or other rights directly or indirectly convertible, exercisable or exchangeable for Yumanity Common Stock owned approximately 70.3% of the outstanding capital stock of the combined organization. At the closing of the Merger, all shares of Yumanity Common Stock were exchanged for an aggregate of 6,024,433 shares of PTI Common Stock. The total purchase price paid in the Merger, including certain transaction costs, has been allocated to the tangible and intangible assets acquired and liabilities assumed of PTI based on their relative fair values as of the completion of the Merger. Transaction costs primarily included bank fees and professional fees associated with legal counsel, auditors and printers. The following summarizes the purchase price paid in the Merger (in thousands, except share and per share amounts): Number of shares owned by Proteostasis stockholders (1) 2,708,537 Multiplied by fair value per share of Proteostasis common stock (2) $ 22.20 Fair value of shares of combined organization owned by Proteostasis Stockholders $ 60,130 Fair value of Proteostasis stock options assumed in Merger (3) 47 1 Transaction costs 2,68 9 Total purchase price $ 63,290 (1) The number of shares represents 2,609,489 shares of PTI common stock outstanding as of December 22, 2020, plus 25,719 shares issued for the settlement of severance obligations and 21,739 shares issued as compensation for investment banking fees related to the Merger. Additionally, 51,590 shares of restricted stock units were issued as compensation for two consultants hired by PTI. The number of shares reflects the impact of the Reverse Stock Split. (2) Based on the last reported sale price of PTI common stock on the Nasdaq Global Market on December 22, 2020, the closing date of the Merger, and after giving effect to the Reverse Stock Split. (3) Represents the fair value of the PTI options to purchase 194,550 shares of common stock outstanding at the time of the Merger. The purchase price for the Merger was allocated to the net assets acquired on the basis of relative fair values. The following summarizes the allocation of the purchase price to the net tangible and intangible assets acquired (in thousands): Cash and cash equivalents $ 35,111 Prepaid expenses and other current assets 703 Assets held-for-sale 250 Property and equipment, net 290 In-process 28,336 Operating lease right-of-use 15,166 Restricted cash 828 Current liabilities (7,171 ) Operating lease liabilities (10,223 ) Total purchase price $ 63,290 The acquired in-process two

Fair Value Measurements and Mar

Fair Value Measurements and Marketable Securities	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements and Marketable Securities	4. Fair Value Measurements and Marketable Securities The following tables present the Company’s fair value hierarchy for its assets and liabilities, which are measured at fair value on a recurring basis (in thousands): Fair Value Measurements at December 31, 2020 Using: Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 77,129 $ — $ — $ 77,129 Commercial paper — 1,800 — 1,800 Marketable securities: Commercial paper — 4,498 — 4,498 $ 77,129 $ 6,298 $ — $ 83,427 Liabilities: Preferred unit warrant liability $ — $ — $ — $ — Fair Value Measurements at December 31, 2019 Using: Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 13,146 $ — $ — $ 13,146 Marketable securities: Commercial paper — 1,347 — 1,347 $ 13,146 $ 1,347 $ — $ 14,493 Liabilities: Preferred unit warrant liability $ — $ — $ 261 $ 261 Marketable securities were valued by the Company using quoted prices in active markets for similar securities, which represent a Level 2 measurement within the fair value hierarchy. The following table provides a roll-forward of the aggregate fair values of the Company’s preferred units warrant liability, for which fair value was determined by Level 3 inputs (in thousands): Preferred Unit Fair value at December 31, 2018 $ 50 Issuance of warrants to purchase Class B preferred units 223 Change in fair value (12 ) Fair value at December 31, 2019 261 Change in fair value (72 ) Reclassification of warrant liability to permanent equity (189 ) Fair value at December 31, 2020 $ — The preferred unit warrant liability in the table above consisted of the fair value of warrants to purchase preferred units issued in 2018 and 2019 (see Note 11) and was based on significant inputs not observable in the market, which represented a Level 3 measurement within the fair value hierarchy. The Company’s valuation of the preferred unit warrants utilized the Black-Scholes option-pricing model, which incorporated assumptions and estimates to value the preferred unit warrants. The Company assessed these assumptions and estimates at the end of each reporting period. Changes in the fair value of the preferred unit warrants were recognized within other income (expense) in the consolidated statements of operations. The most significant assumption in the Black-Scholes option-pricing model impacting the fair value of the preferred unit warrant liability was the fair value of the underlying preferred units as of each remeasurement date. The Company determined the fair value per unit of these preferred units by taking into consideration its most recent sales of its preferred units as well as additional factors that the Company deemed relevant. Immediately prior to the Merger, all of Holdings’ outstanding warrants were exchanged and became warrants to purchase shares of Yumanity Common Stock. As a result, the fair value of the warrants was reclassified to additional paid-in Marketable securities by security type consisted of the following (in thousands): December 31, 2020 Amortized Gross Gross Fair Commercial paper $ 4,498 $ — $ — $ 4,498 $ 4,498 $ — $ — $ 4,498 December 31, 2019 Amortized Gross Gross Fair Commercial paper $ 1,347 $ — $ — $ 1,347 $ 1,347 $ — $ — $ 1,347 The Company’s marketable securities are due within one year.

Property and Equipment, Net

Property and Equipment, Net	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Property and Equipment, Net	5. Property and Equipment, Net Property and equipment, net consisted of the following (in thousands): December 31, 2020 2019 Laboratory equipment $ 1,674 $ 2,351 Office equipment, computers and software 209 168 Furniture and fixtures 170 5 Leasehold improvements — 85 2,053 2,609 Less: Accumulated depreciation and amortization (1,179 ) (1,592 ) $ 874 $ 1,017 Assets held-for-sale $ 250 $ — Depreciation and amortization expense was $0.8 million and $1.1 million for the years ended December 31, 2020 and 2019, respectively. As of December 31, 2020 the Company had $0.8 million of gross assets under finance leases, which primarily consisted of laboratory equipment, and related accumulated amortization of $0.6 million. At December 31, 2019, the Company had $1.8 million of gross assets under finance leases and related accumulated amortization of $1.3 million.

Collaboration Agreement

Collaboration Agreement	12 Months Ended
	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Collaboration Agreement	6. Collaboration Agreement In June 2020, the Company entered into an exclusive license and research collaboration agreement (the “Collaboration Agreement”) with Merck Sharp & Dohme Corp. (“Merck”) to support the research, development and commercialization of products for the treatment of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar dementia (FTLD). Pursuant to the Collaboration Agreement, the Company granted Merck an exclusive, worldwide license with the right to grant and authorize sublicenses, under certain intellectual property rights related to two certain undisclosed targets in connection with the Company’s ALS and FTLD programs to make, have made, use, import, offer to sell and sell compounds and products covered by such intellectual property rights. In the event that the exploitation of such compound or product would infringe during the term of the Merck Collaboration Agreement a claim of an issued patent controlled by Yumanity, Yumanity also granted Merck a non-exclusive, sublicensable, Under the terms of the Collaboration Agreement, the Company and Merck are each responsible to perform certain research activities in accordance with a mutually agreed upon research plan. Upon the completion of certain stages of the research plan, Merck will elect to either advance and make certain contractual option payments or terminate the applicable research program. If Merck elects not to advance a research program, such program terminates and the rights granted to Merck in the program revert to the Company. Following completion of the research program, Merck is responsible for the development and commercialization of the compounds developed pursuant to the research program and any product containing such compounds. Under the terms of the Collaboration Agreement, the Company received an upfront payment totaling $15.0 million in July 2020 and is eligible to receive up to $280.0 million upon achievement of specified research and development milestones, and up to $250.0 million upon achievement of specified sales- based milestones as well as a tiered, mid-single digit Unless terminated earlier, the Collaboration Agreement will continue in full force and effect until one or more products has received marketing authorization and, thereafter, until expiration of all royalty obligations under the Collaboration Agreement. The Company or Merck may terminate the Collaboration Agreement upon an uncured material breach by the other party or insolvency of the other party. Merck may also terminate the Merck Collaboration Agreement for any reason upon certain notice to the Company. Merck also participated in the Company’s Class C preferred units financing in June 2020 with terms consistent with those of other investors that purchased Class C preferred units in June 2020 (see Note 9). The Class C preferred units were issued at a price of $4.0008 per unit, which was determined to be fair value based on the same price paid by other investors that purchased Class C preferred units in the financing. The equity investment was considered to be distinct from the Collaboration Agreement. The Company assessed the promised goods and services to determine if they are distinct. Based on this assessment, the Company determined that Merck cannot benefit from the promised goods and services separately from the others as they are highly interrelated and therefore not distinct. Accordingly, the promised goods and services represent one combined performance obligation and the entire transaction price was allocated to that single combined performance obligation. The performance obligation is being satisfied over the research term as the Company performs the research and development activities through the first substantive option period, and participates in a Joint Steering Committee to oversee research and development activities. Accordingly, the upfront payment of $15.0 million was recorded as deferred revenue and will be recognized as revenue as the performance obligation is satisfied. The Company recognizes revenue using the cost-to-cost method, the cost-to-cost method, revenue catch-up. At The Company assessed the Collaboration Agreement to determine whether a significant financing component exists and concluded that a significant financing component does not exist.

Accrued Expenses

Accrued Expenses	12 Months Ended
	Dec. 31, 2020
Payables and Accruals [Abstract]
Accrued Expenses	7. Accrued Expenses Accrued expenses consisted of the following (in thousands): December 31, 2020 2019 Accrued employee compensation and benefits $ 4,295 $ 1,318 Accrued external research and development expenses 1,780 689 Accrued professional fees 987 215 Other 789 199 $ 7,851 $ 2,421

Debt

Debt	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Debt	8. Debt Long-term debt consisted of the following (in thousands): December 31, 2020 2019 Principal amount of long-term debt $ 16,123 $ 15,000 Less: Current portion of long-term debt (2,891 ) — Long-term debt, net of current portion 13,232 15,000 Debt discount, net of accretion (348 ) (539 ) Accrued end-of-term 353 9 Long-term debt, net of discount and current portion $ 13,237 $ 14,470 The Company has outstanding borrowings of $15.0 million (“Tranche 1”) under a loan and security agreement entered into in December 2019 (the “New Loan”) with Hercules Capital, Inc. (the “Lender”). The Company may borrow an additional $5.0 million upon the occurrence of a development milestone and an equity event as defined in the agreement (“Tranche 2”), and an additional $10.0 million may become available to be drawn upon lender approval. Borrowings under the New Loan are repayable in monthly interest-only payments until August 1, 2021, with the option to extend an additional six months upon the drawdown of Tranche 2. The interest-only period will be followed by monthly payments of equal principal plus interest until the loan maturity date of January 1, 2024. Outstanding borrowings bear interest at the greater of i) 8.75% and ii) the prime rate as reported in the Wall Street Journal plus 4.00%. A final payment fee of 5.25% of the amounts drawn under the New Loan is due upon the earlier of the maturity date or the repayment date if paid early, whether voluntary or upon acceleration due to default. The Company may repay the New Loan at any time by paying the outstanding principal balance in full, along with any unpaid accrued interest, the final payment fees of 5.25% of the amounts drawn and a prepayment fee calculated on amounts being prepaid. The prepayment fee is 3.0% if the New Loan is repaid within the one-year In April 2020, the New Loan was amended to permit indebtedness consisting of a loan under the Paycheck Protection Program (“PPP”) of the Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”) provided that such loan shall be unsecured, shall not contain any terms or conditions that are adverse to the Lender’s rights under the loan and that the Company will not prepay such loan. In June 2020, the New Loan was amended and an additional final payment fee of $0.3 million became due upon repayment of the loan. On December 22, 2020, the Company entered into an Unconditional Secured Guaranty and Pledge Agreement (the “Guaranty”) with the Lender as a condition to the Lender’s consent to the Merger under the New Loan between Yumanity, Inc. as borrower and the Lender. Immediately prior to the Merger, Yumanity, Inc. entered into a Fourth Amendment and Consent to Loan and Security Agreement dated as of December 22, 2020 with the Lender (the “Loan Amendment”). The Guaranty provides for the Company’s guaranty of Yumanity Inc.’s obligations under the Loan Agreement and provides the Lender a security interest in all of Company’s assets other than intellectual property as collateral. The Loan Amendment provides for the Lender’s consent to the Merger and to the creation and funding of a Silicon Valley Bank Paycheck Protection Program escrow account to hold funds in connection with Yumanity’s outstanding Paycheck Protection Program loan amounts for which Yumanity has submitted a forgiveness application. The Loan Amendment also amends the definition of “Change in Control” to include the situations in which the Company no longer controls Yumanity, Inc. The remaining terms and conditions of the Loan Agreement generally continue in the form existing prior to the Loan Amendment. As of December 31, 2020 and 2019, the interest rate applicable to borrowings under the New Loan was 8.75%. During the year ended December 31, 2020, the weighted average effective interest rate on outstanding borrowings under the New Loan was approximately 12.48%. Borrowings under the New Loan are collateralized by substantially all of the Company’s personal property, other than its intellectual property. There were no financial covenants associated with the New Loan; however, the Company is subject to certain affirmative and negative covenants restricting the Company’s activities, including limitations on dispositions, mergers or acquisitions; encumbering its intellectual property; incurring indebtedness or liens; paying dividends; making certain investments; and engaging in certain other business transactions. The obligations under the New Loan are subject to acceleration upon the occurrence of specified events of default, including a material adverse change in the Company’s business, operations or financial or other condition. Upon the occurrence of an event of default and until such event of default is no longer continuing, the annual interest rate will be 5.0% above the otherwise applicable rate. In April 2020, prior to entering into the Merger Agreement with PTI in August 2020, the Company issued a Promissory Note to Silicon Valley Bank, pursuant to which it received loan proceeds of $1.1 million (the “Loan”) provided under the PPP established under the CARES Act and guaranteed by the U.S. Small Business Administration. The Loan is unsecured, is scheduled to mature on April 24, 2022, and has a fixed interest rate of 1.0% per annum. Equal monthly payments of principal and interest will be due commencing in August 2021 until the maturity date. Interest accrues on the unpaid principal balance from the inception date of the loan. Forgiveness of the Loan is only available for principal that is used for the limited purposes that expressly qualify for forgiveness under U.S. Small Business Administration requirements. The Company has determined to account for the Loan as debt under ASC 470, “Debt”, and has allocated and recorded the loan proceeds between current and non-current 470-50-15-4. As of December 31, 2020, future principal payments due are as follows (in thousands): Year Ending December 31, 2021 $ 2,891 2022 6,305 2023 6,341 2024 586 2025 — $ 16,123

Preferred Units

Preferred Units	12 Months Ended
	Dec. 31, 2020
Text Block [Abstract]
Preferred Units	9. Preferred Units Prior to the Merger, the Company had issued Class A preferred units, Class B preferred units, and Class C preferred units, collectively referred to as the “Preferred Units”. In June 2020, the Company issued and sold 5,404,588 Class C preferred units at a purchase price of $4.0008 per unit, resulting in cash proceeds of $21.2 million net of issuance costs of $0.4 million. In connection with the issuance and sale of Class C preferred units, a majority of the Company’s voting preferred and common unit holders voted to amend the Company’s operating agreement such that Class B preferred unitholders who did not participate in a minimum purchase of Class C preferred units, referred to as non-participating holders, became holders of Class B preferred units referred to as “Defaulting Class B Preferred Units.” Class B preferred units other than the Defaulting Class B Preferred Units are referred to as Ordinary Class B preferred units. The terms of the Defaulting Class B Preferred Units are similar to the terms of common units with respect to distributions, except that Defaulting Class B Preferred Units are treated as one-fifth (1/5) of a common unit. The Defaulting Class B Preferred Units lose their rights associated with Preferred Units and have no voting rights. For accounting purposes, this transaction was treated as an extinguishment of the existing Class B preferred units held by the non-participating holders and the issuance of a new security. The carrying value of $7.0 million for the Class B preferred units exchanged for Defaulting Class B Preferred Units was removed from Preferred units on the balance sheet and the Defaulting Class B Preferred Units were reflected in permanent equity at their issuance date fair value of $0.3 million with the difference $6.7 million reflected as a reduction of accumulated deficit. Preferred Units consisted of the following as of December 31, 2019 (in thousands, except unit amounts): December 31, 2019 Preferred Preferred Units Carrying Liquidation Class A preferred units 8,555,165 8,075,629 $ 53,657 $ 54,591 Class B preferred units 8,960,573 4,315,472 36,042 36,121 17,515,738 12,391,101 $ 89,699 $ 90,712 Yumanity Reorganization and Merger Immediately prior to the Merger on December 22, 2020, pursuant to the Yumanity Reorganization, all of the Class A, Class B, and Class C preferred units converted to shares of Yumanity, Inc. common stock. Pursuant to the Merger, these shares of Yumanity Inc. common stock were then exchanged for shares of PTI common stock based upon the Exchange Ratio and the related carrying value was reclassified to common stock and additional paid-in

Common Stock_Units

Common Stock/Units	12 Months Ended
	Dec. 31, 2020
Stockholders' Equity Note [Abstract]
Common Stock/Units	10. Common Stock/Units As of December 31, 2020, the Company’s certificate of incorporation, as amended and restated, authorized the Company to issue 125,000,000 shares of common stock, par value $0.001 per share, and 5,000,000 shares of preferred stock, par value $0.001 per share, all of which is undesignated. Each share of common stock entitles the holder to one vote for the election of directors and on all matters submitted to a vote of the Company’s stockholders. Common stockholders are entitled to receive dividends, as may be declared by the board of directors, if any, subject to the preferential dividend rights of the preferred stockholders. No cash dividends have been declared or paid to date. Prior to the Yumanity Reorganization, the Company had issued common units. Each common unit entitled the holder to one vote on all matters submitted to a vote of the Company’s members. In the event of any deemed liquidation, dissolution, or winding-up of Prior to the Yumanity Reorganization, the Company also had outstanding restricted incentive units, a form of common units, that generally vested over four years (see Note 12). Yumanity Reorganization Immediately prior to the Merger, pursuant to the Yumanity Reorganization, all of Holdings’ outstanding common units, including the outstanding incentive units, were exchanged and became shares of common stock of Yumanity, Inc. Private Placement Following the Merger, on December 22, 2020, pursuant to the Subscription Agreement, dated as of December 14, 2020, by and among the Company and the purchasers named therein, the Company completed the sale of $33.6 million of the Company’s common stock, par value $0.001 per share to the purchasers in a private placement.

Warrants for Common Stock and P

Warrants for Common Stock and Preferred and Common Units	12 Months Ended
	Dec. 31, 2020
Warrants and Rights Note Disclosure [Abstract]
Warrants for Common Stock and Preferred and Common Units	11. Warrants for Common Stock and Preferred and Common Units Prior to the Merger, in December 2019, in connection with the New Loan (see Note 8), the Company issued 34,946 Class B preferred warrants with an exercise price of $8.37 per unit. Upon issuance of Class C preferred units in June 2020, the warrants for Class B preferred units issued in December 2019 became warrants to purchase of 73,109 Class C preferred units with an exercise price of $4.0008 per unit (see Note 9). Yumanity Reorganization and Merger As of December 31, 2019, the Company had outstanding warrants for the purchase of common units, Class A preferred units, and Class B preferred units (which became warrants to purchase Class C preferred units as described above). Immediately prior to the Merger, pursuant to the Yumanity Reorganization, all of Holdings’ outstanding warrants were exchanged and became warrants to purchase shares of Yumanity common stock. Upon consummation of the Merger, the warrants to purchase shares of Yumanity common stock became warrants to purchase the Company’s common stock. The contractual term of each warrant remained unchanged. No additional warrants were issued in 2020 and no warrants were exercised in 2020. As of December 31, 2020, the Company’s outstanding warrants to purchase shares of common stock of the Company consisted of the following: December 31, 2020 Issuance Date Contractual Class of Number of Exercise August 14, 2015 10 Common 74,622 $ 24.05 October 9, 2015 10 Common 7,798 $ 24.05 June 14, 2018 10 Common 2,152 $ 30.13 December 20, 2019 10 Common 15,414 $ 18.98 99,986

Stock_Equity-Based Compensation

Stock/Equity-Based Compensation	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Stock/Equity-Based Compensation	12. Stock/Equity-Based Compensation Incentive units Prior to the Yumanity Reorganization, the Company’s operating agreement, as amended and restated, provided for the granting of incentive units, a type of common units, to officers, directors, employees, consultants and advisors. Holders of incentive units were entitled to receive distributions in proportion to their ownership percent interest, upon liquidation, that were in excess of the strike price of the award, (the “Participation Threshold”) set by the board of directors on the date of grant. The Participation Threshold was based on the amount that would be distributed in respect of a common unit pursuant to its liquidation preferences, if, upon a hypothetical liquidation of the Company on the date of issuance of such Incentive Unit, the Company sold its assets for their fair market value, satisfied its liabilities and distributed its remaining net assets to holders of units in liquidation. The Company determined that the underlying terms of the incentive units and the intended purpose of the awards were more akin to an equity-based compensation award than a performance bonus or profit-sharing arrangement and, therefore, the incentive units were equity-classified awards. Incentive unit valuation The fair value of each common unit was determined based on a number of objective and subjective factors consistent with the methodologies outlined in the American Institute of Certified Public Accountants Practice Aid, Valuation of Privately-Held-Company Equity Securities Issued as Compensation, including the contemporaneous valuations of the Company’s common units, the Company’s financial condition and operating results, the material risks related to the Company’s business, the Company’s stage of development and business strategy and the likelihood of achieving a liquidity event for the holders of the Company’s common units. Incentive unit activity A summary of unvested incentive unit (a type of common units) activity is as follows: Units Weighted Unvested incentive units at December 31, 2019 15,401 $ 8.68 Issued — $ — Vested (14,008 ) $ 8.68 Forfeited (790 ) $ 8.68 Exchange of incentive units for restricted common stock (603 ) $ 8.68 Unvested incentive units at December 31, 2020 — $ — There were no restricted incentive units granted during the years ended December 31, 2020 and 2019. The aggregate grant-date fair value of restricted incentive units that vested during the years ended December 31, 2020 and 2019 was $0.1 million and $0.4 million, respectively. Unvested incentive units were a type of common unit and were exchanged for restricted common stock of Yumanity as described in Note 10. There were no incentive units outstanding following the Reorganization. As of December 31, 2020, the Company had 292 shares of unvested restricted common stock outstanding, which reflects the effect of the Yumanity Reorganization. Summary of plans Upon completion of the Merger, the Company assumed PTI’s 2016 Stock Option and Incentive Plan (the “2016 Plan”) and PTI’s 2016 Employee Stock Purchase Plan (the “2016 ESPP”). 2016 Stock Option and Incentive Plan On February 3, 2016, PTI’s stockholders approved the 2016 Plan, which became effective on February 9, 2016. The 2016 Plan provides for the grant of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock units, restricted stock awards and other stock-based awards. The number of shares initially reserved for issuance under the 2016 Plan was 79,092 shares. The number of shares of common stock that may be issued under the 2016 Plan will automatically increase each January 1, beginning January 1, 2017, by the lesser of 3% of the shares of the Company’s common stock outstanding on the immediately preceding December 31, or an amount determined by the Company’s board of directors or the compensation committee of the board of directors. The shares of common stock underlying any awards that are forfeited, canceled, repurchased, or are otherwise terminated by the Company under the 2016 Plan and the 2008 Equity Incentive Plan, as amended (the “2008 Plan”) will be added back to the shares of common stock available for issuance under the 2016 Plan. On January 1, 2020, an additional 78,175 shares were reserved for issuance under the 2016 Plan. Options granted under the 2016 Plan with service-based vesting conditions generally vest over four years and expire after ten years. As of December 31, 2020, the total number of shares of the Company’s common stock reserved for issuance under the 2016 Plan was 322,605, of which 76,225 shares are available for future issuance under the 2016 Plan. The number of shares reserved for issuance under the 2016 Plan was increased by 303,495 shares effective as of January 1, 2021 in accordance with the provisions of the 2016 Plan described above. 2016 Employee Stock Purchase Plan On February 3, 2016, PTI’s stockholders approved the 2016 ESPP, which became effective in connection with the completion of the PTI’s initial public offering. A total of 6,938 shares of common stock were initially reserved for issuance under the 2016 ESPP. In addition, the number of shares of common stock that may be issued under the 2016 ESPP will automatically increase each January 1, beginning January 1, 2017, by the lesser of (i) 6,938 shares of common stock, (ii) 1% of the Company’s shares of common stock outstanding on the immediately preceding December 31, or (iii) an amount determined by the Company’s board of directors or the compensation committee of the board of directors. As of December 31, 2020, the total number of shares reserved under the 2016 ESPP was 34,689 shares. The number of shares reserved for issuance under the 2016 ESPP was increased by 6,937 shares effective as of January 1, 2021 in accordance with the provisions of the 2016 ESPP described above. Yumanity Therapeutics, Inc. Amended and Restated 2018 Stock Option and Grant Plan On December 4, 2018, the Company’s board of directors adopted the 2018 Unit Option and Grant Plan (the “2018 Plan”), which was approved by the Company’s members on December 5, 2018. The 2018 Plan provided for the Company to grant unit options, restricted unit awards and unrestricted unit awards to employees, directors and consultants of the Company. As part of the Yumanity Reorganization and the Merger, the 2018 Plan was amended and restated as the “Yumanity Therapeutics, Inc. Amended and Restated 2018 Stock Option and Grant Plan”. Each stock option outstanding under the 2018 Plan at the Effective Time of the Merger was automatically converted into a stock option exercisable for the same number of shares of Yumanity common stock, and then assumed by the Company, based on the Exchange Ratio and the exercise price per share of such outstanding stock option, as adjusted for the Exchange Ratio. The 2018 Plan is administered by the board of directors or, at the discretion of the board of directors, by a committee of the board of directors. The exercise prices, vesting and other restrictions are determined at the discretion of the board of directors, or its committee if so delegated. Options granted under the 2018 Plan with service-based vesting conditions generally vest over four years and expire after ten years. The total number of common shares that may be issued under the 2018 Plan is 1,527,210 as of December 31, 2020. Shares that are forfeited, canceled, reacquired by the Company prior to vesting, satisfied without the issuance of shares or otherwise terminated (other than by exercise) and units that are withheld upon the exercise of an option or settlement of an award to cover exercise price or tax withholding shall be added back to units available under the 2018 Plan. As of December 31, 2020, 776,799 shares remain available for issuance under the 2018 Plan. Under each plan, the exercise price per option granted is not less than the fair market value of common stock as of the date of grant. Yumanity Reorganization and Merger Immediately prior to the Merger, pursuant to the Yumanity Reorganization, all of Holdings’ outstanding options were exchanged on a 1-for-1 Option valuation The fair value of option grants is estimated using the Black-Scholes option-pricing model. Prior to the Merger, the Company was a private company and lacks company-specific historical and implied volatility information. Therefore, it estimates its expected stock/unit volatility based on the historical volatility of a publicly traded set of peer companies. The expected term of the Company’s options has been determined utilizing a midpoint convention estimate. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future. The following table presents, on a weighted average basis, the assumptions used in the Black-Scholes option-pricing model to determine the grant-date fair value of options granted: Year Ended December 31, 2020 2019 Risk-free interest rate 1.1 % 1.7 % Expected volatility 70.9 % 72.1 % Expected dividend yield — — Expected term (in years) 7.8 7.8 Option activity The following table summarizes the Company’s option activity during the year ended December 31, 2020: Number Weighted Weighted Aggregate (in years) (in thousands) Outstanding as of December 31, 2019 815,885 $ 14.71 9.41 $ 1,998 Granted 84,758 $ 16.51 Exercised — — Forfeited (150,232 ) $ 14.99 Assumed as part of the Merger with Proteostasis 194,550 $ 68.48 Outstanding as of December 31, 2020 944,961 $ 20.70 8.29 $ 6,522 Vested and expected to vest as of December 31, 2020 944,961 $ 20.70 8.29 $ 6,522 Options exercisable as of December 31, 2020(1) 944,961 $ 20.70 8.29 $ 6,522 (1) Certain options were immediately exercisable for restricted common stock which vest according to the original vesting terms of the option grant. No options have been exercised prior to vesting. The aggregate intrinsic value of options is calculated as the difference between the exercise price of the options and the fair value of the Company’s common stock/units for those stock/unit options that had exercise prices lower than the fair value of the Company’s common stock/units. The weighted average grant-date fair value of stock/unit options granted during the years ended December 31, 2020 and 2019 was $11.39 per unit and $12.10 per share/unit, respectively. Stock/equity-based compensation The Company recorded stock/equity-based compensation expense related to common stock/unit options and restricted incentive units in the following expense categories in its consolidated statements of operations (in thousands): Year Ended December 31, 2020 2019 Research and development expenses $ 663 $ 674 General and administrative expenses 1,603 871 $ 2,266 $ 1,545 As of December 31, 2020, total unrecognized compensation cost related to unvested options and restricted common stock was $5.2 million, which is expected to be recognized over a weighted average period of 2.6 years. In July 2020, the Company modified 722,009 outstanding unit options with a weighted-average exercise price of $14.90 per common unit to reduce the exercise price to $8.16 per common unit. The Company accounted for the re-pricing

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	13. Income Taxes Prior to the Yumanity Reorganization, Holdings was treated as a partnership for federal income tax purposes and, therefore, its owners, and not Holdings, were subject to U.S. federal or state income taxation on the income of Holdings. Holdings’ directly held subsidiary Yumanity Therapeutics, Inc. was treated as a corporation for U.S. federal income tax purposes and was subject to taxation in the United States. Subsequent to the Yumanity Reorganization, the Company is a corporation and is subject to taxation in the United States. In each reporting period, the Company’s tax provision includes the effects of consolidating the results of the operations of its subsidiary. During the years ended December 31, 2020 and 2019, the Company recorded no income tax benefits for the net operating losses incurred or for the research and development tax credits generated in each year due to its uncertainty of realizing a benefit from those items. The Company has no foreign operations and therefore, has not provided for any foreign taxes. A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate is as follows: Year Ended December 31, 2020 2019 Federal statutory income tax rate (21.0 )% (21.0 )% State taxes, net of federal benefit (1.6 ) (6.1 ) Federal and state research and development tax credits (2.5 ) (1.1 ) In-process 10.4 — Other 1.2 0.4 Change in deferred tax asset valuation allowance 13.5 27.8 Effective income tax rate 0.0 % 0.0 % (1) Represents the tax effect on the in-process Net deferred tax assets consisted of the following (in thousands): December 31, 2020 2019 Deferred tax assets: Net operating loss carryforwards $ 122,460 $ 23,142 Research and development tax credit carryforwards 18,654 2,324 Property and equipment 184 312 Accrued expenses 539 360 Capitalized intellectual property costs 89 109 Stock/equity-based compensation expense 1,084 370 Operating lease liabilities 4,670 79 Other — 103 Total deferred tax assets 147,680 26,799 Deferred tax liabilities: Operating lease right-of-use (5,836 ) (75 ) Other (172 ) — Total deferred tax liabilities (6,008 ) (75 ) Valuation allowance (141,672 ) (26,724 ) Net deferred tax assets $ — $ — As of December 31, 2020, the Company had U.S. federal and state net operating loss carryforwards of $453.8 million and $429.9 million, respectively, which may be available to offset future taxable income. Federal and state net operating loss carryforwards of $228.1 million and $429.9 million, respectively, begin to expire in 2026 and 2030, respectively. Federal net operating loss carryforwards of $225.7 million do not expire but may be limited in their usage to an annual deduction equal to 80% of annual taxable income. As of December 31, 2020, the Company also had U.S. federal and state research and development tax credit carryforwards of $14.3 million and $5.5 million, respectively, which may be available to offset future tax liabilities and begin to expire in 2027. Utilization of the U.S. federal and state net operating loss carryforwards and research and development tax credit carryforwards may be subject to a substantial annual limitation under Sections 382 and 383 of the Internal Revenue Code of 1986, and corresponding provisions of state law, due to ownership changes that have occurred previously or that could occur in the future, including those tax attributes acquired from PTI via the Merger. These ownership changes may limit the amount of carryforwards that can be utilized annually to offset future taxable income or tax liabilities. In general, an ownership change, as defined by Section 382, results from transactions increasing the ownership of certain stockholders or public groups in the stock of a corporation by more than 50% over a three-year period. The Company has not conducted a study to assess whether a change of control has occurred or whether there have been multiple changes of control since inception due to the significant complexity and cost associated with such a study. If the Company has experienced a change of control, as defined by Section 382, at any time since inception, utilization of the net operating loss carryforwards or research and development tax credit carryforwards would be subject to an annual limitation under Section 382, which is determined by first multiplying the value of the Company’s stock at the time of the ownership change by the applicable long-term tax-exempt The Company has evaluated the positive and negative evidence bearing upon its ability to realize the deferred tax assets. Management has considered the Company’s history of cumulative net losses incurred since inception and its lack of commercialization of any products or generation of any revenue from product sales since inception and has concluded that it is more likely than not that the Company will not realize the benefits of the deferred tax assets. Accordingly, a full valuation allowance has been established against the net deferred tax assets as of December 31, 2020 and 2019. Management reevaluates the positive and negative evidence at each reporting period. Changes in the valuation allowance for deferred tax assets during the years ended December 31, 2020 and 2019 related primarily to the increase in net operating loss carryforwards and research and development tax credit carryforwards and were as follows (in thousands): Year Ended December 31, 2020 2019 Valuation allowance as of beginning of year $ 26,724 $ 18,044 Increases recorded to income tax provision 7,777 8,680 Amounts from Merger with PTI 107,171 — Valuation allowance as of end of year $ 141,672 $ 26,724 As of December 31, 2020, the Company had not recorded any amounts for unrecognized tax benefits. The Company’s policy is to record interest and penalties related to income taxes as part of its income tax provision. As of December 31, 2020, the Company had no accrued interest or penalties related to uncertain tax positions and no amounts had been recognized in the Company’s consolidated statements of operations. The Company files income tax returns as prescribed by the tax laws of the jurisdictions in which it operates. In the normal course of business, the Company is subject to examination by federal and state jurisdictions, where applicable. There are currently no pending tax examinations. The Company is open to future tax examination under statute from 2016 to the present; however, carryforward attributes that were generated prior to December 31, 2016 may still be adjusted upon examination by federal, state or local tax authorities if they either have been or will be used in a future period. As part of Congress’ response to the COVID-19 COVID-19 80%-of-income

Net Loss per Share

Net Loss per Share	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Net Loss per Share	14. Net Loss Per Share Basic and diluted net loss per share was calculated as follows (in thousands, except share and per share amounts): Year Ended December 31, 2020 2019 Numerator: Net loss $ (57,487 ) $ (31,209 ) Gain on extinguishment of Class B preferred units 6,697 — Net loss applicable to common shareholders $ (50,790 ) $ (31,209 ) Denominator: Weighted average common shares/units outstanding, basic and diluted 2,354,143 2,121,843 Net loss per share/unit, basic and diluted $ (21.57 ) $ (14.71 ) The following common stock equivalents presented based on amounts outstanding at each period end, have been excluded from the calculation of diluted net loss per share because including them would have had an anti-dilutive impact: As of December 31, 2020 2019 Options to purchase common stock 944,961 815,885 Warrants to purchase common stock or shares convertible into common stock 99,986 99,986 1,044,947 915,871

Leases

Leases	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Leases	15. Leases The Company leased office and laboratory facilities in Cambridge, Massachusetts (the “Old Premises”) from an investor in the Company under a noncancelable operating lease that began in April 2015 and expired in March 2020. In February 2020, the Company amended the lease for the Old Premises to extend the lease expiration to April 30, 2020. The amendment was accounted for as a lease reassessment and the right-of-use asset the right-of-use asset In February 2020, the Company entered into a license agreement with a third party for the use of office and laboratory space in Boston, Massachusetts, commencing in May 2020 (the “New Premises”). The Company determined that this license agreement qualified as a lease under ASC 842, Leases (“ASC 842”). The initial term of the license agreement is three years with the option to extend for a total of three one-year periods a non-exclusive, irrevocable use forty-two unreserved On December 22, 2020, as part of the Merger, the Company acquired a lease for approximately 30,000 square feet of office and laboratory space in Boston, Massachusetts. The lease commenced in January 2018 with rent payments commencing in April 2018. The initial term of the lease was ten years with the option to extend for an additional seven years at fair-market rent at the time of the extension. In addition to use of office and laboratory space, the Company is responsible for paying its allocable portion of building and laboratory operating expenses separately from rent, based on actual costs incurred. Remaining fixed lease payments at the time of the Merger were approximately $14.2 million. On December 22, 2020, the Company recorded an operating lease asset and corresponding lease liability of $10.2 million associated with this lease. The operating lease asset was increased by the value attributable to the below-market lease of $3.1 million and an allocated portion of the excess purchase price for the Merger of $1.9 million (see Note 3). The Company also leases property and equipment under agreements that are accounted for as finance leases. The components of lease cost were as follows (in thousands): Year Ended December 31, 2020 2019 Operating lease cost $ 3,097 $ 1,101 Short-term lease cost $ — $ — Variable lease cost $ 271 $ 583 Finance lease cost: Amortization of lease assets $ 361 $ 896 Interest on lease liabilities 20 55 Total finance lease cost $ 381 $ 951 Supplemental disclosure of cash flow information related to leases was as follows (in thousands): Year Ended December 31, 2020 2019 Cash paid for amounts included in the measurement of operating lease liabilities (operating cash flows) $ 2,461 $ 1,131 Cash paid for amounts included in the measurement of finance lease liabilities (operating cash flows) $ 20 $ 55 Cash paid for amounts included in the measurement of finance lease liabilities (financing cash flows) $ 347 $ 958 Operating lease liabilities arising from obtaining right-of-use $ 10,219 $ 469 Finance lease liabilities arising from obtaining right-of-use $ 102 $ — The weighted-average remaining lease term and discount rate were as follows: As of December 31, 2020 2019 Weighted-average remaining lease term (in years) used for: Operating leases 5.03 0.25 Finance leases 1.26 1.42 Weighted-average discount rate used for: Operating leases 9.01 % 8.11 % Finance leases 6.46 % 6.09 % Because the interest rates implicit in the license agreement and lease agreement assumed from PTI were not readily determinable, the Company’s incremental borrowing rate was used to calculate the present value of each. The present value of the Company’s finance leases was calculated using the rate implicit in the lease. As of December 31, 2020, future annual lease payments under the Company’s real estate operating leases and equipment finance leases were as follows (in thousands): Year Ending December 31, Operating Leases Finance Leases 2021 $ 5,997 $ 173 2022 6,173 49 2023 2,977 — 2024 1,931 — 2025 1,985 — Thereafter 4,841 — Total future lease payments 23,904 222 Less: Imputed interest (4,957 ) (8 ) Total lease liabilities $ 18,947 $ 214 The following table presents lease assets and liabilities and their classification on the consolidated balance sheet (in thousands): Leases Consolidated Balance Sheet Classification Amount Assets: Operating lease assets Operating lease right-of- use $ 23,678 Finance lease assets Property and equipment, net 199 Total leased assets $ 23,877 Liabilities: Current: Operating lease liabilities Operating lease liabilities $ 4,468 Finance lease liabilities Current portion of finance lease obligation 166 Non-current: Operating lease liabilities Operating lease liabilities, net of current portion 14,479 Finance lease liabilities Finance lease obligation, net of current portion 48 Total lease liabilities $ 19,161

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	16. Commitments and Contingencies License agreement The Company has a tangible property and patent license agreement with Whitehead Institute for Biomedical Research (“Whitehead”) entered into in 2016 and subsequently amended in 2016 and 2018, under which the Company obtained a certain exclusive and non-exclusive, know-how one-time last-to-expire Contingent Value Rights Agreement In connection with the Merger, the Company entered into a Contingent Value Rights Agreement (the “CVR Agreement”) with Shareholder Representative Services LLC as representative of the PTI stockholders. The CVR Agreement entitles each holder of Company Common Stock as of immediately prior to the effective time of the Merger (the “Effective Time”) to receive certain net proceeds, if any, derived from the grant, sale or transfer of rights of the CF Assets ( the “CF Assets”) completed during the 9-month 10-year Indemnification agreements In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, contract research organizations, business partners and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors and its executive officers that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. The Company has not incurred any material costs as a result of such indemnifications and is not currently aware of any indemnification claims. Legal Matters Between October 14 and December 7, 2020, following the announcement of the proposed merger among PTI, Yumanity, Inc. and Merger Sub, a wholly owned subsidiary of PTI, nine lawsuits were filed by purported stockholders of PTI challenging the Merger. The first lawsuit, brought as a putative class action, is captioned Aniello v. Proteostasis Therapeutics, Inc., et al. 1:20-cv-08578 Culver v. Proteostasis Therapeutics, Inc., et al 1:20-cv-08595 Donolo v. Proteostasis Therapeutics, Inc. et al 1:20-cv-01400 Straube v. Proteostasis Therapeutics, Inc., et al 1:20-cv-08653 Beck v. Proteostasis Therapeutics, Inc., et al 1:20-cv-08783 Dreyer v. Proteostasis Therapeutics, Inc., et al 1:20-cv-05193 Kopkin v. Proteostasis Therapeutics, Inc. et al No. 1:20-cv-12103 No. 1:20-cv-10275 No. 1:20-cv-10296 Aniello Donolo 14a-9 Donolo Aniello S-4 8-K

Defined Contribution Plan

Defined Contribution Plan	12 Months Ended
	Dec. 31, 2020
Retirement Benefits [Abstract]
Defined Contribution Plan	17. Defined Contribution Plan The Company has a 401(k) defined contribution plan (the “401(k) Plan”) for its employees. Eligible employees may make pretax contributions to the 401(k) Plan up to statutory limits. To date, the Company has not made any contributions to the plan.

Related Parties

Related Parties	12 Months Ended
	Dec. 31, 2020
Related Party Transactions [Abstract]
Related Parties	18. Related Parties The Company leased certain office and laboratory space from an investor in the Company until May 2020 (see Note 15). Lease expense associated with this lease agreement for the years ended December 31, 2020 and 2019 was $0.4 million and $1.1 million, respectively. Amounts paid to the investor under the lease agreement during the years ended December 31, 2020 and 2019 were $0.6 million and $1.7 million, respectively. There were no amounts payable to the investor as of December 31, 2020 or 2019.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	19. Subsequent Events Sublease agreement In January 2021, the Company entered into an 18-month On March 29, 2021, the New Loan was amended again to allow for the creation of a new foreign subsidiary, as well as changing certain covenants related to the financial operations of said subsidiary. The subsidiary has not yet been formed.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Basis of Presentation	Basis of presentation The Company’s consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”). The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiary. All intercompany accounts and transactions have been eliminated in consolidation. Unless otherwise noted, all references to common stock/unit share and per share amounts have also been adjusted to reflect the Exchange Ratio.
Use of Estimates	Use of estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting periods. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, revenue recognition, the accrual of research and development expenses, the valuation of common units prior to the Merger and the valuation of stock/unit-based awards. The Company bases its estimates on historical experience, known trends and other market-specific or other relevant factors that it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates as there are changes in circumstances, facts, and experience. Actual results may differ from those estimates or assumptions.
Segment Information	Segment information The Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions. All of the Company’s tangible assets are held in the United States.
Concentrations of credit risk and of significant suppliers	Concentrations of credit risk and of significant suppliers Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents and marketable securities. At times the Company may maintain cash and investment balances in excess of federally insured limits. The Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. The Company relies, and expects to continue to rely, on a small number of vendors to provide services, supplies and materials related to its discovery programs. These programs could be adversely affected by a significant interruption in these services or the availability of materials.
Deferred financing costs	Deferred financing costs The Company capitalizes certain legal and other third-party fees that are directly associated with obtaining access to capital under credit facilities. Deferred financing costs incurred in connection with obtaining access to capital are recorded in prepaid expenses and other current assets and are amortized over the term of the credit facility. Deferred financing costs related to a recognized debt liability are recorded as a reduction of the carrying amount of the debt liability and amortized to interest expense using the effective interest method over the repayment term.
Cash Equivalents	Cash equivalents The Company considers all highly liquid investments with original maturities of three months or less at the date of purchase to be cash equivalents.
Restricted Cash	Restricted cash Amounts included in restricted cash represent amounts pledged as collateral for letters of credit required for a security deposit on the Company’s leased facilities, which was returned to the Company in August 2020, as well as amounts pledged as collateral for Company credit cards as part of the terms of the “New Loan” (see Note 8). These amounts are classified as restricted cash (current) and restricted cash (non-current), respectively, (non-current)
Property and Equipment	Property and equipment Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation and amortization expense is recognized using the straight-line method over the estimated useful life of each asset as follows: Estimated Useful Life Laboratory equipment 2 - 3 years Office equipment, computers and software 2 - 5 years Furniture and fixtures 2 - 7 years Leasehold improvements Shorter of remaining term of lease or useful life Costs for capital assets not yet placed into service are capitalized as construction-in-progress and
Assets held-for-sale	Assets held-for-sale The Company classifies assets as held-for-sale held-for-sale held-for-sale.
Impairment of Long-Lived Assets	Impairment of long-lived assets The Company evaluates its long-lived assets, which consist primarily of property and equipment and right-of-use
Acquisitions	Acquisitions Acquisitions of assets or a group of assets that do not meet the definition of a business are accounted for as asset acquisitions using the cost accumulation method, whereby the cost of the acquisition, including certain transaction costs, is allocated to the assets acquired on the basis of relative fair values. No goodwill is recognized in an asset acquisition. Intangible assets that are acquired in an asset acquisition for use in research and development activities which have an alternative future use are capitalized as in-process
Fair value measurements	Fair value measurements Certain assets and liabilities are carried at fair value under GAAP. 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. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: • Level 1 — Quoted prices in active markets for identical assets or liabilities. • Level 2 — Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. • Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques. The Company’s cash equivalents and marketable securities are carried at fair value, determined according to the fair value hierarchy described above (see Note 4). The carrying values of the Company’s accounts payable and accrued expenses approximate their fair values due to the short-term nature of these liabilities. The carrying value of the Company’s long-term debt under its loan and security agreement approximates its fair value due to its variable interest rate.
Marketable securities	Marketable securities The Company’s marketable securities, which consist of debt securities, are classified as available-for-sale and The Company conducts periodic reviews to identify and evaluate each investment in the Company’s portfolio that has an unrealized loss to determine whether a credit loss exists. An unrealized loss exists when the current fair value of an individual security is less than its amortized cost basis. A credit loss is estimated by considering available information relevant to the collectability of the security and information about past events, current conditions, and reasonable and supportable forecasts. Any credit loss is recorded as a charge to other income (expense), net, not to exceed the amount of the unrealized loss. Unrealized losses other than the credit loss are recognized in accumulated other comprehensive income (loss). When determining whether a credit loss exists, the Company considers several factors, including whether the Company has the intent to sell the security or whether it is more likely than not that the Company will be required to sell the security prior to recovery of its amortized cost basis. If the Company has an intent to sell, or if it is more likely than not that the Company will be required to sell a debt security in an unrealized loss position before recovery of its amortized cost basis, the Company will write down the security to its fair value and record the corresponding charge as a component of other income (expense), net. No declines in value were deemed to be credit losses or other than temporary during the year ended December 31, 2020.
Revenue recognition	Revenue recognition The Company accounts for its one collaboration arrangement, entered into in June 2020, under ASC Topic 606, Revenue From Contracts With Customers (ASC 606). For additional information on the Company’s collaboration agreement, see Note 6, Collaboration Agreement, to these consolidated financial statements. Under ASC 606, an entity recognizes revenue when its customer obtains control of promised goods or services in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements within the scope of ASC 606, the entity performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price, including variable consideration, if any; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company only applies the five-step model to contracts when it is probable that the entity will collect the consideration to which it is entitled in exchange for the goods or services it transfers to the customer. The Company assesses the goods or services promised within each contract and determines those that are performance obligations. Arrangements that include rights to additional goods or services that are exercisable at a customer’s discretion are generally considered options. The Company assesses if these options provide a material right to the customer and if so, they are considered performance obligations. The identification of material rights requires judgments related to the determination of the value of the underlying license relative to the option exercise price, including assumptions about technical feasibility and the probability of developing a candidate that would be subject to the option rights. The exercise of a material right is accounted for as a contract modification for accounting purposes. The Company assesses whether each promised good or service is distinct for the purpose of identifying the performance obligations in the contract. This assessment involves subjective determinations and requires management to make judgments about the individual promised goods or services and whether such are separable from the other aspects of the contractual relationship. Promised goods and services are considered distinct provided that: (i) the customer can benefit from the good or service either on its own or together with other resources that are readily available to the customer (that is, the good or service is capable of being distinct) and (ii) the entity’s promise to transfer the good or service to the customer is separately identifiable from other promises in the contract (that is, the promise to transfer the good or service is distinct within the context of the contract). In assessing whether a promised good or service is distinct, the Company considers factors such as the research, manufacturing and commercialization capabilities of the collaboration partner and the availability of the associated expertise in the general marketplace. The Company also considers the intended benefit of the contract in assessing whether a promised good or service is separately identifiable from other promises in the contract. If a promised good or service is not distinct, an entity is required to combine that good or service with other promised goods or services until it identifies a bundle of goods or services that is distinct. The transaction price is then determined and allocated to the identified performance obligations in proportion to their standalone selling prices (“SSP”) on a relative SSP basis. SSP is determined at contract inception and is not updated to reflect changes between contract inception and when the performance obligations are satisfied. Determining the SSP for performance obligations requires significant judgment. In developing the SSP for a performance obligation, the Company considers applicable market conditions and relevant entity- specific factors, including factors that were contemplated in negotiating the agreement with the customer and estimated costs. The Company validates the SSP for performance obligations by evaluating whether changes in the key assumptions used to determine the SSP will have a significant effect on the allocation of arrangement consideration between multiple performance obligations. If the consideration promised in a contract includes a variable amount, the Company estimates the amount of consideration to which it will be entitled in exchange for transferring the promised goods or services to a customer. The Company determines the amount of variable consideration by using the expected value method or the most likely amount method. The Company includes the unconstrained amount of estimated variable consideration in the transaction price. The amount included in the transaction price is constrained to the amount for which it is probable that a significant reversal of cumulative revenue recognized will not occur. At the end of each subsequent reporting period, the Company re-evaluates the cumulative catch-up basis If an arrangement includes development and regulatory milestone payments, the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the Company’s control or the licensee’s control, such as regulatory approvals, are generally not considered probable of being achieved until those approvals are received. For arrangements with licenses of intellectual property that include sales-based royalties, including milestone payments based on the level of sales, and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes royalty revenue and sales-based milestones at the later of (i) when the related sales occur, or (ii) when the performance obligation to which the royalty has been allocated has been satisfied. The Company records amounts as accounts receivable when the right to consideration is deemed unconditional. When consideration is received, or such consideration is unconditionally due, from a customer prior to transferring goods or services to the customer under the terms of a contract, a contract liability is recorded for deferred revenue. In determining the transaction price, the Company adjusts consideration for the effects of the time value of money if the timing of payments provides the Company with a significant benefit of financing. The Company does not assess whether a contract has a significant financing component if the expectation at contract inception is such that the period between payment by the licensees and the transfer of the promised goods or services to the licensees will be one year or less. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) each performance obligation is satisfied, either at a point in time or over time, and if over time, recognition is based on the use of an output or input method.
Classification and accretion of preferred units	Classification and accretion of preferred units The Company’s preferred units were classified outside of members’ deficit on the consolidated balance sheets because the holders of such units had redemption rights in the event of a deemed liquidation that, in certain situations, were not solely within the control of the Company. The occurrence of a deemed liquidation event was not determined to be probable in any period prior to the Merger, therefore the carrying values of the preferred units were not being accreted to their redemption values.
Research and Development Costs	Research and development costs Costs for research and development activities are expensed in the period in which they are incurred. Research and development expenses consist of costs incurred in performing research and development activities, including salaries and bonuses, stock/equity-based compensation, employee benefits, facilities costs, laboratory supplies, depreciation and amortization, manufacturing expenses, and external costs of vendors engaged to conduct research and preclinical development activities and clinical trials as well as the cost of licensing technology. Upfront payments under license agreements are expensed upon receipt of the license, and annual maintenance fees under license agreements are expensed in the period in which they are incurred. Milestone payments under license agreements are accrued, with a corresponding expense being recognized, in the period in which the milestone is determined to be probable of achievement and the related amount is reasonably estimable. Non -
Research, development, and manufacturing contract costs and accruals	Research, development, and manufacturing contract costs and accruals The Company has entered into various research, development, and manufacturing contracts with research institutions and other companies. These agreements are generally cancelable, and related costs are recorded as research and development expenses as incurred. The Company records accruals for estimated ongoing research and development costs. When billing terms under these contracts do not coincide with the timing of when the work is performed, the Company is required to make estimates of outstanding obligations to those third parties as of period end. Any accrual estimates are based on a number of factors, including the Company’s knowledge of the progress towards completion of the research, development, and manufacturing activities, invoicing to date under the contracts, communication from the research institutions and other companies of any actual costs incurred during the period that have not yet been invoiced, and the costs included in the contracts. Significant judgments and estimates may be made in determining the accrued balances at the end of any reporting period. Actual results could differ from the estimates made by the Company. The historical accrual estimates made by the Company have not been materially different from the actual costs.
Patent Costs	Patent costs All patent-related costs incurred in connection with filing and prosecuting patent applications are expensed as incurred due to the uncertainty about the recovery of the expenditure. Amounts incurred are classified as general and administrative expenses.
Stock/equity-based compensation	Stock/equity-based compensation The Company measures awards with service-based vesting or performance-based vesting granted to employees, non-employees and for non-employees, both The Company classifies stock/equity-based compensation expense in its consolidated statements of operations in the same manner in which the award recipient’s payroll costs are classified or in which the award recipient’s service payments are classified.
Income Taxes	Income taxes Prior to the Yumanity Reorganization, Holdings was organized as a Limited Liability Company and subject to the provisions of Subchapter K of the Internal Revenue Code. As such, Holdings was not viewed as a taxpaying entity in any jurisdiction and did not require a provision for income taxes. Each member was responsible for the tax liability, if any, related to its proportionate share of the member’s taxable income. The Company’s wholly owned corporate subsidiary was a taxpaying entity. After the Yumanity Reorganization, the Company and its subsidiary are both taxpaying entities. The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or in the Company’s tax returns. Deferred tax assets and liabilities are determined on the basis of the differences between the financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. Potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits expected and considering prudent and feasible tax planning strategies. The Company accounts for uncertainty in income taxes recognized in the consolidated financial statements by applying a two-step process deemed more-likely-than-not to
Comprehensive Loss	Comprehensive loss Comprehensive loss includes net loss as well as other changes in stockholders’ equity/members’ deficit that result from transactions and economic events other than those with its members. The Company’s only elements of other comprehensive loss are unrealized gains (losses) on marketable securities.
Net Loss per Share	Net loss per share Basic net income (loss) per common share is computed by dividing the net income (loss) by the weighted average number of shares of common stock outstanding for the period. Diluted net income (loss) per common share is computed by dividing net income (loss) by the weighted average number of common shares outstanding for the period, including potential dilutive common shares assuming the dilutive effect of outstanding common stock equivalents. For periods in which the Company reported a net loss, diluted net loss per common share is the same as basic net loss per common share, since dilutive common shares are not assumed to have been issued if their affect is anti-dilutive.
Leases	Leases In accordance with ASC 842, the Company determines at the inception of a contract if such arrangement is or contains a lease. A contract is or contains a lease if the contract conveys the right to control the use of an identified asset for a period of time in exchange for consideration. The Company classifies leases at the lease commencement date as operating or finance leases and records a right-of-use asset The Company often enters into contracts that contain both lease and non-lease components. Non-lease components and non-lease components of right-of-use assets Lease liabilities and their corresponding right-of-use assets Certain of the Company’s leases include options to extend or terminate the lease. The amounts determined for the Company’s right-of-use assets
Recently adopted and recently issued accounting pronouncements	Recently adopted accounting pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial (“ASU 2016-13”), which ASU 2016-13 replaces to available-for-sale debt ASU No. 2018-19, Codification for non-public entities ASU 2016-13. The ASU No. 2019-05, Financial (“ASU 2019-05”). ASU 2019-05 provides ASU 2016-13 is Recently issued accounting pronouncements In December 2019, the FASB issued ASU No. 2019-12 ,

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Summary of property and equipment	Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation and amortization expense is recognized using the straight-line method over the estimated useful life of each asset as follows: Estimated Useful Life Laboratory equipment 2 - 3 years Office equipment, computers and software 2 - 5 years Furniture and fixtures 2 - 7 years Leasehold improvements Shorter of remaining term of lease or useful life

Merger Accounting (Tables)

Merger Accounting (Tables)	12 Months Ended
	Dec. 31, 2020
Business Combinations [Abstract]
Summary of purchase price paid in the Merger	The total purchase price paid in the Merger, including certain transaction costs, has been allocated to the tangible and intangible assets acquired and liabilities assumed of PTI based on their relative fair values as of the completion of the Merger. Transaction costs primarily included bank fees and professional fees associated with legal counsel, auditors and printers. The following summarizes the purchase price paid in the Merger (in thousands, except share and per share amounts): Number of shares owned by Proteostasis stockholders (1) 2,708,537 Multiplied by fair value per share of Proteostasis common stock (2) $ 22.20 Fair value of shares of combined organization owned by Proteostasis Stockholders $ 60,130 Fair value of Proteostasis stock options assumed in Merger (3) 47 1 Transaction costs 2,68 9 Total purchase price $ 63,290 (1) The number of shares represents 2,609,489 shares of PTI common stock outstanding as of December 22, 2020, plus 25,719 shares issued for the settlement of severance obligations and 21,739 shares issued as compensation for investment banking fees related to the Merger. Additionally, 51,590 shares of restricted stock units were issued as compensation for two consultants hired by PTI. The number of shares reflects the impact of the Reverse Stock Split. (2) Based on the last reported sale price of PTI common stock on the Nasdaq Global Market on December 22, 2020, the closing date of the Merger, and after giving effect to the Reverse Stock Split. (3) Represents the fair value of the PTI options to purchase 194,550 shares of common stock outstanding at the time of the Merger.
Summary of allocation of the purchase price to the net tangible and intangible assets	The purchase price for the Merger was allocated to the net assets acquired on the basis of relative fair values. The following summarizes the allocation of the purchase price to the net tangible and intangible assets acquired (in thousands): Cash and cash equivalents $ 35,111 Prepaid expenses and other current assets 703 Assets held-for-sale 250 Property and equipment, net 290 In-process 28,336 Operating lease right-of-use 15,166 Restricted cash 828 Current liabilities (7,171 ) Operating lease liabilities (10,223 ) Total purchase price $ 63,290

Fair Value Measurements and M_2

Fair Value Measurements and Marketable Securities (Tables)	12 Months Ended
	Dec. 31, 2020
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis	The following tables present the Company’s fair value hierarchy for its assets and liabilities, which are measured at fair value on a recurring basis (in thousands): Fair Value Measurements at December 31, 2020 Using: Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 77,129 $ — $ — $ 77,129 Commercial paper — 1,800 — 1,800 Marketable securities: Commercial paper — 4,498 — 4,498 $ 77,129 $ 6,298 $ — $ 83,427 Liabilities: Preferred unit warrant liability $ — $ — $ — $ — Fair Value Measurements at December 31, 2019 Using: Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 13,146 $ — $ — $ 13,146 Marketable securities: Commercial paper — 1,347 — 1,347 $ 13,146 $ 1,347 $ — $ 14,493 Liabilities: Preferred unit warrant liability $ — $ — $ 261 $ 261
Summary of Marketable Securities	Marketable securities by security type consisted of the following (in thousands): December 31, 2020 Amortized Gross Gross Fair Commercial paper $ 4,498 $ — $ — $ 4,498 $ 4,498 $ — $ — $ 4,498 December 31, 2019 Amortized Gross Gross Fair Commercial paper $ 1,347 $ — $ — $ 1,347 $ 1,347 $ — $ — $ 1,347
Level 3 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Summary of Fair Value Of Warrant Liability	The following table provides a roll-forward of the aggregate fair values of the Company’s preferred units warrant liability, for which fair value was determined by Level 3 inputs (in thousands): Preferred Unit Fair value at December 31, 2018 $ 50 Issuance of warrants to purchase Class B preferred units 223 Change in fair value (12 ) Fair value at December 31, 2019 261 Change in fair value (72 ) Reclassification of warrant liability to permanent equity (189 ) Fair value at December 31, 2020 $ —

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Schedule of Property and Equipment, Net	Property and equipment, net consisted of the following (in thousands): December 31, 2020 2019 Laboratory equipment $ 1,674 $ 2,351 Office equipment, computers and software 209 168 Furniture and fixtures 170 5 Leasehold improvements — 85 2,053 2,609 Less: Accumulated depreciation and amortization (1,179 ) (1,592 ) $ 874 $ 1,017 Assets held-for-sale $ 250 $ —

Accrued Expenses (Tables)

Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2020
Payables and Accruals [Abstract]
Schedule of Accrued Expenses	Accrued expenses consisted of the following (in thousands): December 31, 2020 2019 Accrued employee compensation and benefits $ 4,295 $ 1,318 Accrued external research and development expenses 1,780 689 Accrued professional fees 987 215 Other 789 199 $ 7,851 $ 2,421

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Summary of Long-term Debt	Long-term debt consisted of the following (in thousands): December 31, 2020 2019 Principal amount of long-term debt $ 16,123 $ 15,000 Less: Current portion of long-term debt (2,891 ) — Long-term debt, net of current portion 13,232 15,000 Debt discount, net of accretion (348 ) (539 ) Accrued end-of-term 353 9 Long-term debt, net of discount and current portion $ 13,237 $ 14,470
Summary of Future Principal Payments Due	As of December 31, 2020, future principal payments due are as follows (in thousands): Year Ending December 31, 2021 $ 2,891 2022 6,305 2023 6,341 2024 586 2025 — $ 16,123

Preferred Units (Tables)

Preferred Units (Tables)	12 Months Ended
	Dec. 31, 2020
Temporary Equity Disclosure [Abstract]
Summary of Preferred Units	Preferred Units consisted of the following as of December 31, 2019 (in thousands, except unit amounts): December 31, 2019 Preferred Preferred Units Carrying Liquidation Class A preferred units 8,555,165 8,075,629 $ 53,657 $ 54,591 Class B preferred units 8,960,573 4,315,472 36,042 36,121 17,515,738 12,391,101 $ 89,699 $ 90,712

Warrants for Common Stock and_2

Warrants for Common Stock and Preferred and Common Units (Tables)	12 Months Ended
	Dec. 31, 2020
Warrants and Rights Note Disclosure [Abstract]
Summary of warrants	As of December 31, 2020, the Company’s outstanding warrants to purchase shares of common stock of the Company consisted of the following: December 31, 2020 Issuance Date Contractual Class of Number of Exercise August 14, 2015 10 Common 74,622 $ 24.05 October 9, 2015 10 Common 7,798 $ 24.05 June 14, 2018 10 Common 2,152 $ 30.13 December 20, 2019 10 Common 15,414 $ 18.98 99,986

Stock_Equity-Based Compensati_2

Stock/Equity-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Summary of Restricted Stock Unit Activity and Related Information	A summary of unvested incentive unit (a type of common units) activity is as follows: Units Weighted Unvested incentive units at December 31, 2019 15,401 $ 8.68 Issued — $ — Vested (14,008 ) $ 8.68 Forfeited (790 ) $ 8.68 Exchange of incentive units for restricted common stock (603 ) $ 8.68 Unvested incentive units at December 31, 2020 — $ —
Schedule of Share-based Payment Award Stock Options Valuation Assumptions	The following table presents, on a weighted average basis, the assumptions used in the Black-Scholes option-pricing model to determine the grant-date fair value of options granted: Year Ended December 31, 2020 2019 Risk-free interest rate 1.1 % 1.7 % Expected volatility 70.9 % 72.1 % Expected dividend yield — — Expected term (in years) 7.8 7.8
Summary of Stock Option Activity	The following table summarizes the Company’s option activity during the year ended December 31, 2020: Number Weighted Weighted Aggregate (in years) (in thousands) Outstanding as of December 31, 2019 815,885 $ 14.71 9.41 $ 1,998 Granted 84,758 $ 16.51 Exercised — — Forfeited (150,232 ) $ 14.99 Assumed as part of the Merger with Proteostasis 194,550 $ 68.48 Outstanding as of December 31, 2020 944,961 $ 20.70 8.29 $ 6,522 Vested and expected to vest as of December 31, 2020 944,961 $ 20.70 8.29 $ 6,522 Options exercisable as of December 31, 2020(1) 944,961 $ 20.70 8.29 $ 6,522 (1) Certain options were immediately exercisable for restricted common stock which vest according to the original vesting terms of the option grant. No options have been exercised prior to vesting.
Summary of Stock-based Compensation Expense, Including Shares Issued to Consultants for Services	The Company recorded stock/equity-based compensation expense related to common stock/unit options and restricted incentive units in the following expense categories in its consolidated statements of operations (in thousands): Year Ended December 31, 2020 2019 Research and development expenses $ 663 $ 674 General and administrative expenses 1,603 871 $ 2,266 $ 1,545

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Schedule of Effective Income Tax Rate Reconciliation	A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate is as follows: Year Ended December 31, 2020 2019 Federal statutory income tax rate (21.0 )% (21.0 )% State taxes, net of federal benefit (1.6 ) (6.1 ) Federal and state research and development tax credits (2.5 ) (1.1 ) In-process 10.4 — Other 1.2 0.4 Change in deferred tax asset valuation allowance 13.5 27.8 Effective income tax rate 0.0 % 0.0 % (1) Represents the tax effect on the in-process
Schedule of Net Deferred Tax Assets (liabilities)	Net deferred tax assets consisted of the following (in thousands): December 31, 2020 2019 Deferred tax assets: Net operating loss carryforwards $ 122,460 $ 23,142 Research and development tax credit carryforwards 18,654 2,324 Property and equipment 184 312 Accrued expenses 539 360 Capitalized intellectual property costs 89 109 Stock/equity-based compensation expense 1,084 370 Operating lease liabilities 4,670 79 Other — 103 Total deferred tax assets 147,680 26,799 Deferred tax liabilities: Operating lease right-of-use (5,836 ) (75 ) Other (172 ) — Total deferred tax liabilities (6,008 ) (75 ) Valuation allowance (141,672 ) (26,724 ) Net deferred tax assets $ — $ —
Changes in Valuation Allowance for Deferred Tax Assets	Changes in the valuation allowance for deferred tax assets during the years ended December 31, 2020 and 2019 related primarily to the increase in net operating loss carryforwards and research and development tax credit carryforwards and were as follows (in thousands): Year Ended December 31, 2020 2019 Valuation allowance as of beginning of year $ 26,724 $ 18,044 Increases recorded to income tax provision 7,777 8,680 Amounts from Merger with PTI 107,171 — Valuation allowance as of end of year $ 141,672 $ 26,724

Net Loss per Share (Tables)

Net Loss per Share (Tables)	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Net Loss per Share	Basic and diluted net loss per share was calculated as follows (in thousands, except share and per share amounts): Year Ended December 31, 2020 2019 Numerator: Net loss $ (57,487 ) $ (31,209 ) Gain on extinguishment of Class B preferred units 6,697 — Net loss applicable to common shareholders $ (50,790 ) $ (31,209 ) Denominator: Weighted average common shares/units outstanding, basic and diluted 2,354,143 2,121,843 Net loss per share/unit, basic and diluted $ (21.57 ) $ (14.71 )
Schedule of Antidilutive Securities Excluded from Computation of Diluted Weighted-average Shares Outstanding	The following common stock equivalents presented based on amounts outstanding at each period end, have been excluded from the calculation of diluted net loss per share because including them would have had an anti-dilutive impact: As of December 31, 2020 2019 Options to purchase common stock 944,961 815,885 Warrants to purchase common stock or shares convertible into common stock 99,986 99,986 1,044,947 915,871

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2020
Lessee Disclosure [Abstract]
Elements of Lease Expense	The components of lease cost were as follows (in thousands): Year Ended December 31, 2020 2019 Operating lease cost $ 3,097 $ 1,101 Short-term lease cost $ — $ — Variable lease cost $ 271 $ 583 Finance lease cost: Amortization of lease assets $ 361 $ 896 Interest on lease liabilities 20 55 Total finance lease cost $ 381 $ 951
Summary of supplemental disclosure of cash flow information related to leases	Supplemental disclosure of cash flow information related to leases was as follows (in thousands): Year Ended December 31, 2020 2019 Cash paid for amounts included in the measurement of operating lease liabilities (operating cash flows) $ 2,461 $ 1,131 Cash paid for amounts included in the measurement of finance lease liabilities (operating cash flows) $ 20 $ 55 Cash paid for amounts included in the measurement of finance lease liabilities (financing cash flows) $ 347 $ 958 Operating lease liabilities arising from obtaining right-of-use $ 10,219 $ 469 Finance lease liabilities arising from obtaining right-of-use $ 102 $ —
Schedule of weighted-average remaining lease term and discount rate	The weighted-average remaining lease term and discount rate were as follows: As of December 31, 2020 2019 Weighted-average remaining lease term (in years) used for: Operating leases 5.03 0.25 Finance leases 1.26 1.42 Weighted-average discount rate used for: Operating leases 9.01 % 8.11 % Finance leases 6.46 % 6.09 %
Summary of future annual operating lease payments	As of December 31, 2020, future annual lease payments under the Company’s real estate operating leases and equipment finance leases were as follows (in thousands): Year Ending December 31, Operating Leases Finance Leases 2021 $ 5,997 $ 173 2022 6,173 49 2023 2,977 — 2024 1,931 — 2025 1,985 — Thereafter 4,841 — Total future lease payments 23,904 222 Less: Imputed interest (4,957 ) (8 ) Total lease liabilities $ 18,947 $ 214
Summary of table presents lease assets and liabilities and their classification on the consolidated balance sheet	The following table presents lease assets and liabilities and their classification on the consolidated balance sheet (in thousands): Leases Consolidated Balance Sheet Classification Amount Assets: Operating lease assets Operating lease right-of- use $ 23,678 Finance lease assets Property and equipment, net 199 Total leased assets $ 23,877 Liabilities: Current: Operating lease liabilities Operating lease liabilities $ 4,468 Finance lease liabilities Current portion of finance lease obligation 166 Non-current: Operating lease liabilities Operating lease liabilities, net of current portion 14,479 Finance lease liabilities Finance lease obligation, net of current portion 48 Total lease liabilities $ 19,161

Nature of Business and Basis _2

Nature of Business and Basis of Presentation - Additional Information (Detail) $ / shares in Units, $ in Thousands	Dec. 22, 2020$ / sharesshares	Dec. 31, 2020USD ($)$ / sharesshares	Dec. 31, 2019USD ($)$ / shares
Nature of Business [Line Items]
Merger Agreement Exchange Ratio	0.2108
Accumulated deficit | $		$ (147,810)	$ (97,020)
Net loss | $		$ (57,487)	$ (31,209)
Common stock price per share		$ 0.001	$ 0.001
Private Placement [Member]
Nature of Business [Line Items]
Stock issued during period, shares, issued | shares		1,460,861
Common stock price per share	$ 0.001
PTI Common Stock [Member]
Nature of Business [Line Items]
Stockholders equity reverse stock split conversion ratio	1-for-20 reverse stock split of its common stock (the “Reverse Stock Split”)
Stock issued during period, shares | shares	6,024,433
Yumanity Common Stock [Member]
Nature of Business [Line Items]
Common stock price per share	$ 0.01

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Significant Accounting Policies [Line Items]
Impairment of long-lived assets	$ 0	$ 0
Restricted cash and cash equivalents	82,885	14,246	$ 5,179
Cash and cash equivalents	80,819	14,021
Restricted cash	$ 2,100	$ 200

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of property and equipment (Detail)	12 Months Ended
	Dec. 31, 2020
Laboratory Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Laboratory Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	2 years
Office Equipment Computers And Software [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	5 years
Office Equipment Computers And Software [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	2 years
Furniture and Fixtures [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	7 years
Furniture and Fixtures [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	2 years
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	Shorter of remaining term of lease or useful life

Merger Accounting - Summary of

Merger Accounting - Summary of purchase price paid in the Merger (Detail) - USD ($) $ / shares in Units, $ in Thousands		Dec. 31, 2020	Dec. 22, 2020
Business Acquisition [Line Items]
Number of shares owned by Proteostasis stockholders	[1]		2,708,537
Multiplied by fair value per share of Proteostasis common stock	[2]		$ 22.20
Fair value of shares of combined organization to be owned by Proteostasis stockholders			$ 60,130
Fair value of Proteostasis stock options assumed in Merger	[3]		471
Transaction costs			2,689
PTI [Member]
Business Acquisition [Line Items]
Total purchase price		$ 63,290	$ 63,290
[1]	The number of shares represents 2,609,489 shares of PTI common stock outstanding as of December 22, 2020, plus 25,719 shares issued for the settlement of severance obligations and 21,739 shares issued as compensation for investment banking fees related to the Merger. Additionally, 51,590 shares of restricted stock units were issued as compensation for two consultants hired by PTI. The number of shares reflects the impact of the Reverse Stock Split.
[2]	Based on the last reported sale price of PTI common stock on the Nasdaq Global Market on December 22, 2020, the closing date of the Merger, and after giving effect to the Reverse Stock Split.
[3]	Represents the fair value of the PTI options to purchase 194,550 shares of common stock outstanding at the time of the Merger.

Merger Accounting - Summary o_2

Merger Accounting - Summary of allocation of the purchase price to the net tangible and intangible assets (Detail) - PTI [Member] - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 22, 2020
Business Acquisition [Line Items]
Cash and cash equivalents	$ 35,111
Prepaid expenses and other current assets	703
Assets held-for-sale	250
Property and equipment, net	290
In-process research and development	28,336
Operating lease right-of-use assets	15,166
Restricted cash	828
Current liabilities	(7,171)
Operating lease liabilities	(10,223)
Total purchase price	$ 63,290	$ 63,290

Merger Accounting - Additional

Merger Accounting - Additional information (Detail)	Dec. 22, 2020shares
PTI [Member]
Business Acquisition [Line Items]
Equity interests issued or issuable number of shares issued	6,024,433
Shares outstanding	2,609,489
Shares issued for settlement of severance obligations	25,719
Shares issued as compensation for investment banking fee	21,739
Restricted stock units issued as compensation for consultants	51,590
Shares of common stock outstanding at the time of the Merger	194,550
Immediately Following Merger [Member] | Former Yumanity Stock And Option Holders [Member]
Business Acquisition [Line Items]
Equity interest in acquiree percentage	70.30%
Immediately Following Merger [Member] | PTI Stock And Option Holders [Member]
Business Acquisition [Line Items]
Equity interest in acquiree percentage	29.70%

Fair Value Measurements and M_3

Fair Value Measurements and Marketable Securities - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Assets:
Total assets	$ 83,427	$ 14,493
Liabilities:
Preferred unit warrant liability	0	261
Commercial Paper [Member]
Assets:
Cash equivalents	1,800
Marketable securities	4,498	1,347
Money Market Funds [Member]
Assets:
Cash equivalents	77,129	13,146
Level 1 [Member]
Assets:
Total assets	77,129	13,146
Liabilities:
Preferred unit warrant liability	0	0
Level 1 [Member] | Commercial Paper [Member]
Assets:
Cash equivalents	0
Marketable securities	0	0
Level 1 [Member] | Money Market Funds [Member]
Assets:
Cash equivalents	77,129	13,146
Level 2 [Member]
Assets:
Total assets	6,298	1,347
Liabilities:
Preferred unit warrant liability	0	0
Level 2 [Member] | Commercial Paper [Member]
Assets:
Cash equivalents	1,800
Marketable securities	4,498	1,347
Level 2 [Member] | Money Market Funds [Member]
Assets:
Cash equivalents	0	0
Level 3 [Member]
Assets:
Total assets	0	0
Liabilities:
Preferred unit warrant liability	0	261	$ 50
Level 3 [Member] | Commercial Paper [Member]
Assets:
Cash equivalents	0
Marketable securities	0	0
Level 3 [Member] | Money Market Funds [Member]
Assets:
Cash equivalents	$ 0	$ 0

Fair Value Measurements and M_4

Fair Value Measurements and Marketable Securities - Summary of Fair Value Of Warrant Liability (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Fair Value Of Warrant Liability [Line Items]
Fair value, beginning	$ 261
Change in fair value	(72)	$ (12)
Reclassification of warrant liability to permanent equity	(189)
Fair value, ending	0	261
Level 3 [Member]
Schedule Of Fair Value Of Warrant Liability [Line Items]
Fair value, beginning	261	50
Issuance of warrants to purchase Class B preferred units		223
Change in fair value	(72)	(12)
Reclassification of warrant liability to permanent equity	(189)
Fair value, ending	$ 0	$ 261

Fair Value Measurements and M_5

Fair Value Measurements and Marketable Securities - Summary of Marketable Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 4,498	$ 1,347
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	4,498	1,347
Commercial Paper [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,498	1,347
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	$ 4,498	$ 1,347

Fair Value Measurements and M_6

Fair Value Measurements and Marketable Securities - Additional Information (Detail)	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Marketable securities maturity year	1 year

Property and Equipment, Net - S

Property and Equipment, Net - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 2,053	$ 2,609
Less: Accumulated depreciation and amortization	(1,179)	(1,592)
Property and Equipment, Net	874	1,017
Assets held-for-sale	250
Laboratory equipment [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	1,674	2,351
Office equipment, computers and software [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	209	168
Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 170	5
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross		$ 85

Property and Equipment, Net - A

Property and Equipment, Net - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Finance Leased Assets, Gross	$ 2,053	$ 2,609
Accumulated amortization of finance lease	1,179	1,592
Depreciation and amortization	770	1,057
Finance Lease [Member]
Property, Plant and Equipment [Line Items]
Finance Leased Assets, Gross	800	1,800
Accumulated amortization of finance lease	$ 600	$ 1,300

Collaboration Agreement - Addit

Collaboration Agreement - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Jul. 31, 2020	Dec. 31, 2020	Jun. 30, 2020
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue from collaborative arrangement		$ 6,896
Class C Preferred Units
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Stock price per share			$ 4.0008
License And Research Collaboration Agreement | Merck
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront payments received	$ 15,000
Deferred revenue additions	$ 15,000
Revenue remaining performance obligation		8,100
Revenue from collaborative arrangement		$ 6,900
License And Research Collaboration Agreement | Merck | Class C Preferred Units
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Stock price per share	$ 4.0008
License And Research Collaboration Agreement | Merck | Research and Development | Maximum [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaborative arrangement, milestone payments receivable	$ 280,000
License And Research Collaboration Agreement | Merck | Sales Based | Maximum [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaborative arrangement, milestone payments receivable	$ 250,000

Accrued Expenses - Schedule of

Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Payables and Accruals [Abstract]
Accrued employee compensation and benefits	$ 4,295	$ 1,318
Accrued external research and development expenses	1,780	689
Accrued professional fees	987	215
Other	789	199
Total accrued expenses	$ 7,851	$ 2,421

Debt - Summary of Long-term Deb

Debt - Summary of Long-term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Long-term Debt, Unclassified [Abstract]
Principal amount of long-term debt	$ 16,123	$ 15,000
Less: Current portion of long-term debt	(2,891)	0
Long-term debt, net of current portion	13,232	15,000
Debt discount, net of accretion	(348)	(539)
Accrued end-of-term payment	353	9
Long-term debt, net of discount and current portion	$ 13,237	$ 14,470

Debt - Summary of Future Princi

Debt - Summary of Future Principal Payments Due (Detail) $ in Thousands	Dec. 31, 2020USD ($)
Long-term Debt, Unclassified [Abstract]
2021	$ 2,891
2022	6,305
2023	6,341
2024	586
2025	0
Total	$ 16,123

Debt - Additional Information (

Debt - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Apr. 30, 2020	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term non current		$ 16,123		$ 15,000
Upon Lender Approval
Debt Instrument [Line Items]
Debt instrument additional loan amount				$ 10,000
New Loan
Debt Instrument [Line Items]
Frequency of periodic payment		monthly
Repayment terms		Borrowings under the New Loan are repayable in monthly interest-only payments until August 1, 2021, with the option to extend an additional six months upon the drawdown of Tranche 2. The interest-only period will be followed by monthly payments of equal principal plus interest until the loan maturity date of January 1, 2024.
Debt maturity date		Jan. 1, 2024
Outstanding borrowing bear interest rate		8.75%		8.75%
Debt instrument final fee percentage		5.25%
Accrued end-of-term payment			$ 300
Debt weighted average interest rate		12.48%
New Loan | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument fixed interest rate		8.75%
Debt instrument variable spread		4.00%
Debt instrument description of variable spread		prime rate as reported in the Wall Street Journal
New Loan | Before One Year Anniversary
Debt Instrument [Line Items]
Debt instrument prepayment fee percentage		3.00%
New Loan | After One Year But Before Second Anniversary
Debt Instrument [Line Items]
Debt instrument prepayment fee percentage		2.00%
New Loan | After Second Year But Before Maturity
Debt Instrument [Line Items]
Debt instrument prepayment fee percentage		1.00%
New Loan | Additional Rate in Event Of Default
Debt Instrument [Line Items]
Debt instrument fixed interest rate		5.00%
New Loan | Tranche One
Debt Instrument [Line Items]
Long-term non current				$ 15,000
New Loan | Tranche Two
Debt Instrument [Line Items]
Debt instrument additional loan amount				$ 5,000
Paycheck Protection Program Loan
Debt Instrument [Line Items]
Debt maturity date		Apr. 24, 2022
Debt instrument fixed interest rate		1.00%
Proceeds from Paycheck Protection Program loan	$ 1,100

Preferred Units - Summary of Pr

Preferred Units - Summary of Preferred Units (Detail) - Preferred Units $ in Thousands	Dec. 31, 2019USD ($)shares
Temporary Equity [Line Items]
Preferred Units Authorized	17,515,738
Preferred Units Issued	12,391,101
Preferred Units Outstanding	12,391,101
Carrying Value | $	$ 89,699
Liquidation Preference | $	$ 90,712
Class A Preferred Units
Temporary Equity [Line Items]
Preferred Units Authorized	8,555,165
Preferred Units Issued	8,075,629
Preferred Units Outstanding	8,075,629
Carrying Value | $	$ 53,657
Liquidation Preference | $	$ 54,591
Class B Preferred Units
Temporary Equity [Line Items]
Preferred Units Authorized	8,960,573
Preferred Units Issued	4,315,472
Preferred Units Outstanding	4,315,472
Carrying Value | $	$ 36,042
Liquidation Preference | $	$ 36,121

Preferred Units - Additional In

Preferred Units - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2020	Dec. 22, 2020
Defaulting Class B Preferred Units
Temporary Equity [Line Items]
Preferred unit as a percentage of common stock unit		20.00%
Preferred units carrying value before reclassification		$ 7,000
Defaulting Class B Preferred Units | Portion at Fair Value Measurement [Member]
Temporary Equity [Line Items]
Preferred units classified to permanent equity at issuance date fair value		300
Prior to Merger [Member] | After Yumanity Reorganization [Member]
Temporary Equity [Line Items]
Preferred units outstanding			0
Retained Earnings [Member] | Defaulting Class B Preferred Units
Temporary Equity [Line Items]
Reclassification of defaulting preferred units to permanent equity		6,700
Class C Preferred Units
Temporary Equity [Line Items]
Temporary equity stock issued during period shares new issues	5,404,588
Stock price per share	$ 4.0008
Proceeds from issuance of LLC preferred units	$ 21,200
Payments of stock issuance costs	$ 400	$ 388

Common Stock_Units - Additional

Common Stock/Units - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Dec. 22, 2020	Dec. 31, 2020	Dec. 31, 2019
Common stock, shares authorized		125,000,000	0
Common stock, par value		$ 0.001	$ 0.001
Preferred stock, shares authorized		5,000,000	0
Preferred stock, par value		$ 0.001	$ 0.001
Cash dividends		$ 0
Voting description		Each share of common stock entitles the holder to one vote
Private Placement [Member]
Common stock, par value	$ 0.001
Common Stock [Member] | Private Placement [Member]
Common stock issued	$ 33,600
Common Units [Member] | Prior to Yumanity Reorganization [Member]
Voting description		Each common unit entitled the holder to one vote
Restricted Incentive Common Units [Member] | Prior to Yumanity Reorganization [Member]
Common stock units vested		4 years

Warrants for Common Stock and_3

Warrants for Common Stock and Preferred and Common Units - Summary of warrants (Detail)	Dec. 31, 2020$ / sharesshares
Class of Warrant or Right [Line Items]
Number of Shares of Common Stock Issuable	99,986
Common Stock [Member] | August 14, 2015
Class of Warrant or Right [Line Items]
Contractual Term	10 years
Number of Shares of Common Stock Issuable	74,622
Exercise Price | $ / shares	$ 24.05
Common Stock [Member] | October 9, 2015
Class of Warrant or Right [Line Items]
Contractual Term	10 years
Number of Shares of Common Stock Issuable	7,798
Exercise Price | $ / shares	$ 24.05
Common Stock [Member] | June 14, 2018
Class of Warrant or Right [Line Items]
Contractual Term	10 years
Number of Shares of Common Stock Issuable	2,152
Exercise Price | $ / shares	$ 30.13
Common Stock [Member] | December 20, 2019
Class of Warrant or Right [Line Items]
Contractual Term	10 years
Number of Shares of Common Stock Issuable	15,414
Exercise Price | $ / shares	$ 18.98

Warrants for Common Stock and_4

Warrants for Common Stock and Preferred and Common Units - Additional Information (Detail) - $ / shares	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Class of Warrant or Right [Line Items]
Number of Shares of Common Stock Issuable	99,986
Class B Preferred Units | New Loan
Class of Warrant or Right [Line Items]
Number of Shares of Common Stock Issuable			34,946
Exercise Price			$ 8.37
Class B to Class C Preferred Units
Class of Warrant or Right [Line Items]
Number of Shares of Common Stock Issuable		73,109
Exercise Price		$ 4.0008

Stock_Equity-Based Compensati_3

Stock/Equity-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Feb. 03, 2016	Jul. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2021	Jan. 01, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average exercise price			$ 11.39	$ 12.10
Number of unvested restricted common stock outstanding			0	15,401
Weighted-average exercise price of share options			$ 20.70	$ 14.71
Amount of cost not yet recognized for nonvested award under share-based payment arrangement.			$ 5,200
Share-based Payment Arrangement, Expense			$ 2,266	$ 1,545
Number of outstanding Stock options			944,961	815,885
Compensation cost not yet recognized, period for recognition			2 years 7 months 6 days
Restricted Incentive Units RSU [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted incentive units grant date fair value			$ 100	$ 400
Number of unvested restricted common stock outstanding			292
Units granted			0	0
2018 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized			1,527,210
Common stock available for future issuance			776,799
2018 Plan | Service Based [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, expiration period			10 years
Share-based payment award, vest period			4 years
Modified Unit Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of outstanding Stock options		722,009
Modified Unit Options [Member] | Vested [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense		$ 100
Modified Unit Options [Member] | Unvested [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount of cost not yet recognized for nonvested award under share-based payment arrangement.		$ 500
2016 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for issuance	79,092		322,605
Common stock available for future issuance			76,225
Common stock reserved for issuance, percentage of number of shares of common stock outstanding	3.00%
2016 Plan [Member] | Service Based [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, expiration period			10 years
Share-based payment award, vest period			4 years
2016 Plan [Member] | Additional [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for issuance						78,175
2016 ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for issuance	6,938		34,689
Common stock reserved for issuance	6,938
Common stock reserved for issuance, percentage of number of shares of common stock outstanding	1.00%
Subsequent Event [Member] | 2016 Plan [Member] | Additional [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for issuance					303,495
Subsequent Event [Member] | 2016 ESPP [Member] | Additional [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for issuance					6,937
After Yumanity Reorganization [Member] | Restricted Incentive Units RSU [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of incentive units			0	0
After Modification [Member] | Modified Unit Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average exercise price of share options		$ 8.16
Before Modification [Member] | Modified Unit Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average exercise price of share options		$ 14.90

Stock_Equity-Based Compensati_4

Stock/Equity-Based Compensation - Summary of Restricted Stock Unit Activity and Related Information (Detail)	12 Months Ended
	Dec. 31, 2020$ / sharesshares
Number of Shares
Unvested balance at December 31, 2019 | shares	15,401
Issued | shares	0
Vested | shares	(14,008)
Forfeited | shares	(790)
Exchange of incentive units for restricted common stock | shares	(603)
Unvested balance at December 31, 2020 | shares	0
Weighted Average Grant Date Fair Value
Unvested balance at December 31, 2019 | $ / shares	$ 8.68
Issued | $ / shares	0
Vested | $ / shares	8.68
Forfeited | $ / shares	8.68
Exchange of incentive units for restricted common stock | $ / shares	8.68
Unvested balance at December 31, 2020 | $ / shares	$ 0

Stock_Equity-Based Compensati_5

Stock/Equity-Based Compensation - Schedule of Share-based Payment Award Stock Options Valuation Assumptions (Detail)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price And Additional Disclosures [Abstract]
Risk-free interest rate	1.10%	1.70%
Expected volatility	70.90%	72.10%
Expected dividend yield	0.00%	0.00%
Expected term (in years)	7 years 9 months 18 days	7 years 9 months 18 days

Stock_Equity-Based Compensati_6

Stock/Equity-Based Compensation - Summary of Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Number of Shares/Units
Outstanding at December 31, 2019	815,885
Granted	84,758
Exercised	0
Forfeited	(150,232)
Assumed as part of the Merger with Proteostasis	194,550
Outstanding at December 31, 2020	944,961	815,885
Vested and expected to vest at December 31, 2020	944,961
Options exercisable at December 31, 2020	944,961
Weighted Average Exercise Price
Outstanding at December 31, 2019	$ 14.71
Granted	16.51
Exercised	0
Forfeited	14.99
Assumed as part of the Merger with Proteostasis	68.48
Outstanding at December 31, 2020	20.70	$ 14.71
Vested and expected to vest at December 31, 2020	20.70
Options exercisable as of December 31, 2020	$ 20.70
Weighted Average Remaining Contractual Term, Outstanding	8 years 3 months 14 days	9 years 4 months 27 days
Weighted Average Remaining Contractual Term, Vested and expected to vest at December 31, 2020	8 years 3 months 14 days
Weighted Average Remaining Contractual Term, Options exercisable at December 31, 2020	8 years 3 months 14 days
Aggregate Intrinsic Value, Outstanding	$ 6,522	$ 1,998
Aggregate Intrinsic Value, Vested and expected to vest at December 31, 2020	6,522
Aggregate Intrinsic Value, Options exercisable at December 31, 2020	$ 6,522

Stock_Equity-Based Compensati_7

Stock/Equity-Based Compensation - Summary of Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Stock-based compensation expense	$ 2,266	$ 1,545
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Stock-based compensation expense	663	674
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Stock-based compensation expense	$ 1,603	$ 871

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Line Items]
Accrued interest or penalties	$ 0
Unrecognized Tax Benefits	0
Foreign operations	0
Provision for income taxes	0	$ 0
Amounts for unrecognized tax benefits, interest or penalties	0
Federal [Member]
Income Tax Disclosure [Line Items]
Operating Loss Carryforwards	453.8
Research and development tax credit carry-forwards	$ 14.3
Tax credit carry-forwards begin to expire year	2027
State [Member]
Income Tax Disclosure [Line Items]
Operating Loss Carryforwards	$ 429.9
Research and development tax credit carry-forwards	$ 5.5
Tax credit carry-forwards begin to expire year	2027
Non Expirable [Member] | Federal [Member]
Income Tax Disclosure [Line Items]
Operating Loss Carryforwards	$ 225.7
Effective Income Tax Rate Deduction, Percent	80.00%
Expirable [Member] | Federal [Member]
Income Tax Disclosure [Line Items]
Operating Loss Carryforwards	$ 228.1
Operating loss carry-forwards begin to expire year	2026
Expirable [Member] | State [Member]
Income Tax Disclosure [Line Items]
Operating Loss Carryforwards	$ 429.9
Operating loss carry-forwards begin to expire year	2030
Minimum [Member]
Income Tax Disclosure [Line Items]
Open Tax Year	2016

Income Taxes - Schedule of Effe

Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Detail)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Federal statutory income tax rate	(21.00%)	(21.00%)
State taxes, net of federal benefit	(1.60%)	(6.10%)
Federal and state research and development tax credits	(2.50%)	(1.10%)
In-process research and development	10.40%	0.00%
Other	1.20%	0.40%
Change in deferred tax asset valuation allowance	13.50%	27.80%
Effective income tax rate	(0.00%)	(0.00%)

Income Taxes - Schedule of Net

Income Taxes - Schedule of Net Deferred Tax Assets (liabilities) (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets:
Net operating loss carryforwards	$ 122,460	$ 23,142
Research and development tax credit carryforwards	18,654	2,324
Property and equipment	184	312
Accrued expenses	539	360
Capitalized intellectual property costs	89	109
Stock/equity-based compensation expense	1,084	370
Operating lease liabilities	4,670	79
Other	0	103
Total deferred tax assets	147,680	26,799
Deferred tax liabilities:
Operating lease right-of-use assets	(5,836)	(75)
Other	(172)	0
Total deferred tax liabilities	(6,008)	(75)
Valuation allowance	(141,672)	(26,724)	$ (18,044)
Net deferred tax assets	$ 0	$ 0

Income Taxes - Changes in Valua

Income Taxes - Changes in Valuation Allowance for Deferred Tax Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Valuation allowance as of beginning of year	$ 26,724	$ 18,044
Increases recorded to income tax provision	7,777	8,680
Amounts from Merger with PTI	107,171	0
Valuation allowance as of end of year	$ 141,672	$ 26,724

Net Loss per Share - Schedule o

Net Loss per Share - Schedule of Basic and Diluted Net Loss per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Numerator:
Net loss applicable to common shareholders	$ (50,790)	$ (31,209)
Net loss	$ (57,487)	$ (31,209)
Denominator:
Weighted average common shares/units outstanding, basic and diluted	2,354,143	2,121,843
Net loss per share/unit, basic and diluted	$ (21.57)	$ (14.71)
Class B Preferred Units
Numerator:
Gain on extinguishment of Class B preferred units	$ 6,697	$ 0

Net Loss per Share - Schedule_2

Net Loss per Share - Schedule of Antidilutive Securities Excluded from Computation of Diluted Weighted-average Shares Outstanding (Detail) - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities outstanding	1,044,947	915,871
Options to Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities outstanding	944,961	815,885
Warrants to purchase common stock or shares convertible into common stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities outstanding	99,986	99,986

Leases - Additional Information

Leases - Additional Information (Detail) $ in Thousands	Dec. 22, 2020USD ($)ft²	May 23, 2020USD ($)	May 01, 2020USD ($)	Feb. 29, 2020USD ($)	May 31, 2020	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Jan. 19, 2018
Operating Lease, Right-of-Use Asset
Increase in operating lease right-of-use assets						$ 23,678	$ 275
Operating lease assets						$ 23,678	$ 275
Old Premises Cambridge [Member]
Operating Lease, Right-of-Use Asset
Increase in operating lease right-of-use assets				$ 100
Increase (decrease) in operating lease liability				(100)
Lease expiration date					May 23, 2020
Operating lease assets				$ 100
New Premises Boston [Member]
Operating Lease, Right-of-Use Asset
Increase in operating lease right-of-use assets			$ 10,600
Increase (decrease) in operating lease liability			10,200
Percentage of escalation of License fee				3.00%
Total Amount of License fee				$ 12,000
License term				3 years
Operating lease assets			$ 10,600
Merger Laboratory Boston [Member]
Operating Lease, Right-of-Use Asset
Operating lease, initial term								10 years
Operating lease, option to extend additional term								7 years
Increase in operating lease right-of-use assets	$ 10,200
Increase (decrease) in operating lease liability	$ 10,200
Number of Square Feet | ft²	30,000
Operating lease, payments	$ 14,200
Operating lease assets	10,200
Merger Laboratory Boston [Member] | Portion of Excess Merger Purchase Price [Member]
Operating Lease, Right-of-Use Asset
Increase in operating lease right-of-use assets	1,900
Operating lease assets	1,900
Merger Laboratory Boston [Member] | Value Attributable to Below Market Lease [Member]
Operating Lease, Right-of-Use Asset
Increase in operating lease right-of-use assets	3,100
Operating lease assets	$ 3,100
Maximum [Member] | Old Premises Cambridge [Member]
Operating Lease, Right-of-Use Asset
Operating leases, rent expense		$ 100

Leases - Summary of lease cost

Leases - Summary of lease cost (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Lease cost
Operating lease cost	$ 3,097	$ 1,101
Short-term Lease Cost
Variable lease cost	271	583
Finance lease cost, amortization of lease assets	361	896
Finance lease cost, interest on lease liabilities	20	55
Total finance lease cost	$ 381	$ 951

Leases - Summary of supplementa

Leases - Summary of supplemental disclosure of cash flow information related to leases (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Schedule of Supplemental disclosure of cash flow information related to leases [Abstract]
Cash paid for amounts included in the measurement of operating lease liabilities (operating cash flows)	$ 2,461	$ 1,131
Cash paid for amounts included in the measurement of finance lease liabilities (operating cash flows)	20	55
Cash paid for amounts included in the measurement of finance lease liabilities (financing cash flows)	347	958
Operating lease liabilities arising from obtaining right-of-use assets	10,219	$ 469
Finance lease liabilities arising from obtaining right-of-use assets	$ 102

Leases - Schedule of weighted-a

Leases - Schedule of weighted-average remaining lease term and discount rate (Detail)	Dec. 31, 2020	Dec. 31, 2019
Schedule of weighted average remaining lease term and discount rate [Abstract]
Weighted-average remaining lease term (in years) used for Operating leases	5 years 10 days	3 months
Weighted-average remaining lease term (in years) used for Finance leases	1 year 3 months 3 days	1 year 5 months 1 day
Weighted-average discount rate for Operating leases	9.01%	8.11%
Weighted-average discount rate used for Finance leases	6.46%	6.09%

Leases - Summary of future annu

Leases - Summary of future annual Operating lease payments (Detail) $ in Thousands	Dec. 31, 2020USD ($)
Operating Leases
2021	$ 5,997
2022	6,173
2023	2,977
2024	1,931
2025	1,985
Thereafter	4,841
Total future lease payments	23,904
Less: Imputed interest	(4,957)
Total lease liabilities	18,947
Finance Leases
2021	173
2022	49
Total future lease payments	222
Less: Imputed interest	(8)
Total lease liabilities	$ 214

Leases - Summary of table pres

Leases - Summary of table presents lease assets and liabilities and their classification on the consolidated balance sheet (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets:
Operating lease assets	$ 23,678	$ 275
Finance lease assets	199
Total leased assets	23,877
Current:
Operating lease liabilities	4,468	291
Finance lease liabilities	166	343
Non-current:
Operating lease liabilities	14,479
Finance lease liabilities	48	$ 116
Total lease liabilities	$ 19,161

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2020USD ($)shares
Contingent Value Rights Agreement [Member] | Shareholder Representative Series LLC [Member]
Long-term Purchase Commitment [Line Items]
Period of agreement	9 months
Business combination contingent consideration agreement	$ 0
Whitehead Institute for Biomedical Research [Member]
Long-term Purchase Commitment [Line Items]
Common unit issued | shares	300,000
Common unit value	$ 800,000
Whitehead Institute for Biomedical Research [Member] | Maximum [Member]
Long-term Purchase Commitment [Line Items]
Payment of license fees	100,000
Annual cost maintenance	100,000
Whitehead Institute for Biomedical Research [Member] | Maximum [Member] | Developmental and Regulatory [Member] | First Two Licensed Products [Member]
Long-term Purchase Commitment [Line Items]
Contractual Obligation	$ 1,900,000

Defined Contribution Plan - Add

Defined Contribution Plan - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2020USD ($)
Postemployment Benefits [Abstract]
Company's contribution to plan	$ 0

Related Parties - Additional In

Related Parties - Additional Information (Detail) - Investor [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Operating lease expense	$ 0.4	$ 1.1
Amounts paid under lease agreement	0.6	1.7
Due to related parties current	$ 0	$ 0

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - Subsequent Event [Member] $ in Millions	Jan. 01, 2021	Jan. 31, 2021USD ($)ft²
Subsequent Event [Line Items]
Future minimum sublease rentals | $		$ 2.9
Sublease	18 months
Area of Real Estate Property | ft²		30,000