$CARM
Carisma Therapeutics Inc Stock $carm

$carm Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000148500321000044 Filed on March 15, 2021

Income Statement

Concept	2019 Q4	2018 Q4	2018
Revenue	$0.00	$0.00	$0.00
YoY Change
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin	$3.300M	$3.500M	$11.62M
YoY Change	-5.71%	75.88%	43.99%
% of Gross Profit
Research & Development	$5.420M	$4.670M	$14.08M
YoY Change	16.06%	50.16%	12.53%
% of Gross Profit
Depreciation & Amortization	$60.00K	$50.00K	$210.0K
YoY Change	20.0%	-28.57%	-27.59%
% of Gross Profit
Operating Expenses	$33.74M	$7.066M	$34.50M
YoY Change	377.47%	7.17%	16.24%
Operating Profit	-$33.74M	-$7.066M	-$34.50M
YoY Change	377.47%	7.17%	17.93%
Interest Expense		$0.00	$0.00
YoY Change
% of Operating Profit
Other Income/Expense, Net	$190.0K	$310.0K	$807.0K
YoY Change	-38.71%	520.0%	257.08%
Pretax Income	-$33.55M	-$6.760M	-$33.69M
YoY Change	396.3%	3.21%	16.07%
Income Tax		$0.00	$0.00
% Of Pretax Income
Net Earnings	-$33.55M	-$6.757M	-$33.69M
YoY Change	396.57%	3.21%	16.07%
Net Earnings / Revenue
Basic Earnings Per Share			-$0.55
Diluted Earnings Per Share	-$322.6K	-$87.20K	-$0.55
COMMON SHARES
Basic Shares Outstanding	104.7M shares	77.46M shares	61.77M shares
Diluted Shares Outstanding			61.77M shares

Balance Sheet

Concept	2019 Q4	2018 Q4	2018
SHORT-TERM ASSETS
Cash & Short-Term Investments	$48.10M	$50.40M	$50.40M
YoY Change	-4.56%	242.86%	242.86%
Cash & Equivalents	$48.12M	$50.42M	$50.40M
Short-Term Investments
Other Short-Term Assets	$6.300M	$1.300M	$1.300M
YoY Change	384.62%	333.33%	333.33%
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets	$54.45M	$51.76M	$51.80M
YoY Change	5.2%	245.48%	245.33%
LONG-TERM ASSETS
Property, Plant & Equipment	$238.0K	$321.0K	$300.0K
YoY Change	-25.86%	-38.51%	-40.0%
Goodwill	$13.10M	$13.06M
YoY Change	0.28%	0.0%
Intangibles	$46.40M	$46.40M
YoY Change	0.0%	0.0%
Long-Term Investments
YoY Change
Other Assets	$196.0K	$0.00	$0.00
YoY Change		-100.0%	-100.0%
Total Long-Term Assets	$59.92M	$59.81M	$59.80M
YoY Change	0.19%	-0.52%	-0.5%
TOTAL ASSETS
Total Short-Term Assets	$54.45M	$51.76M	$51.80M
Total Long-Term Assets	$59.92M	$59.81M	$59.80M
Total Assets	$114.4M	$111.6M	$111.6M
YoY Change	2.51%	48.56%	48.6%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$1.902M	$1.367M	$1.400M
YoY Change	39.14%	50.72%	55.56%
Accrued Expenses	$6.169M	$4.746M	$4.700M
YoY Change	29.98%	24.47%	23.68%
Deferred Revenue	$0.00
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$8.517M	$6.113M	$6.100M
YoY Change	39.33%	29.51%	29.79%
LONG-TERM LIABILITIES
Long-Term Debt	$0.00	$0.00	$0.00
YoY Change
Other Long-Term Liabilities	$0.00	$313.0K	$48.70M
YoY Change	-100.0%	45.58%	22.36%
Total Long-Term Liabilities	$0.00	$313.0K	$48.70M
YoY Change	-100.0%	45.58%	22.36%
TOTAL LIABILITIES
Total Short-Term Liabilities	$8.517M	$6.113M	$6.100M
Total Long-Term Liabilities	$0.00	$313.0K	$48.70M
Total Liabilities	$141.1M	$67.35M	$67.40M
YoY Change	109.44%	1264.82%	18.04%
SHAREHOLDERS EQUITY
Retained Earnings	-$293.5M	-$186.0M
YoY Change	57.79%	22.12%
Common Stock	$107.0K	$77.00K
YoY Change	38.96%	120.0%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	-$26.70M	$44.21M	$44.20M
YoY Change
Total Liabilities & Shareholders Equity	$114.4M	$111.6M	$111.6M
YoY Change	2.51%	48.56%	48.6%

Cashflow Statement

Concept	2019 Q4	2018 Q4	2018
OPERATING ACTIVITIES
Net Income	-$33.55M	-$6.757M	-$33.69M
YoY Change	396.57%	3.21%	16.07%
Depreciation, Depletion And Amortization	$60.00K	$50.00K	$210.0K
YoY Change	20.0%	-28.57%	-27.59%
Cash From Operating Activities	-$13.80M	-$7.650M	-$22.80M
YoY Change	80.39%	110.74%	28.09%
INVESTING ACTIVITIES
Capital Expenditures	$0.00	$0.00	$2.000K
YoY Change			-80.0%
Acquisitions
YoY Change
Other Investing Activities		-$10.00K	$0.00
YoY Change		-150.0%	-100.0%
Cash From Investing Activities	$0.00	-$10.00K	-$2.000K
YoY Change	-100.0%	-150.0%	-102.04%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$0.00
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	4.060M	220.0K	$58.58M
YoY Change	1745.45%	-96.84%	736.3%
NET CHANGE
Cash From Operating Activities	-13.80M	-7.650M	-$22.80M
Cash From Investing Activities	0.000	-10.00K	-$2.000K
Cash From Financing Activities	4.060M	220.0K	$58.58M
Net Change In Cash	-9.740M	-7.440M	$35.75M
YoY Change	30.91%	-322.09%	-435.32%
FREE CASH FLOW
Cash From Operating Activities	-$13.80M	-$7.650M	-$22.80M
Capital Expenditures	$0.00	$0.00	$2.000K
Free Cash Flow	-$13.80M	-$7.650M	-$22.80M
YoY Change	80.39%		28.03%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2018	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	5000	USD
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CY2019	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	5188000	USD
CY2018	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	913000	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	1200000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	535000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	460000	USD
CY2020	us-gaap	Increase Decrease In Accrued Liabilities IncreaseDecreaseInAccruedLiabilities	-2035000	USD
CY2019	us-gaap	Increase Decrease In Accrued Liabilities IncreaseDecreaseInAccruedLiabilities	1556000	USD
CY2018	us-gaap	Increase Decrease In Accrued Liabilities IncreaseDecreaseInAccruedLiabilities	1031000	USD
CY2020	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	3000000	USD
CY2019	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	0	USD
CY2018	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	0	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-30837000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-37521000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-22829000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	8000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	136000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	2000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-8000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-136000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2000	USD
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CY2019	us-gaap	Proceeds From Warrant Exercises ProceedsFromWarrantExercises	5481000	USD
CY2018	us-gaap	Proceeds From Warrant Exercises ProceedsFromWarrantExercises	7315000	USD
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	37958000	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	1936000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	13000	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	98000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	277000	USD
CY2020	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	11000	USD
CY2019	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	8000	USD
CY2018	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	20000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	7268000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	38113000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	35356000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	58583000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-2301000	USD
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CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	48141000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	50442000	USD
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CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	55409000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	48141000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	50442000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	52389000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	48121000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	50422000	USD
CY2020Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	3000000	USD
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CY2020Q4	us-gaap	Restricted Cash And Cash Equivalents Noncurrent RestrictedCashAndCashEquivalentsNoncurrent	20000	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents Noncurrent RestrictedCashAndCashEquivalentsNoncurrent	20000	USD
CY2018Q4	us-gaap	Restricted Cash And Cash Equivalents Noncurrent RestrictedCashAndCashEquivalentsNoncurrent	20000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	55409000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	48141000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	50442000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	154000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	153000	USD
CY2018	us-gaap	Operating Lease Payments OperatingLeasePayments	0	USD
CY2020	sesn	Right Of Use Asset Related To Adoption Of Accounting Standard RightOfUseAssetRelatedToAdoptionOfAccountingStandard	0	USD
CY2019	sesn	Right Of Use Asset Related To Adoption Of Accounting Standard RightOfUseAssetRelatedToAdoptionOfAccountingStandard	236000	USD
CY2018	sesn	Right Of Use Asset Related To Adoption Of Accounting Standard RightOfUseAssetRelatedToAdoptionOfAccountingStandard	0	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	290000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0	USD
CY2019	sesn	Issuance Of Warrant For Common Stock IssuanceOfWarrantForCommonStock	0	USD
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CY2020	sesn	Issuance Of Warrant For Common Stock IssuanceOfWarrantForCommonStock	147000	USD
CY2018	sesn	Issuance Of Warrant For Common Stock IssuanceOfWarrantForCommonStock	0	USD
CY2020	us-gaap	Nature Of Operations NatureOfOperations	DESCRIPTION OF BUSINESS<div style="margin-bottom:6pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Sesen Bio, Inc. ("Sesen" or the “Company”), a Delaware corporation formed in February 2008, is a late-stage clinical company developing targeted fusion protein therapeutics ("TFPTs") for the treatment of patients with cancer. The Company’s most advanced product candidate, Vicineum</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:6.5pt;font-weight:400;line-height:120%;position:relative;top:-3.5pt;vertical-align:baseline">TM</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">, also known as VB4-845, is a locally-administered targeted fusion protein composed of an anti-epithelial cell adhesion molecule ("EpCAM") antibody fragment tethered to a truncated form of </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Pseudomonas exotoxin A</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">. The Company has an ongoing single-arm, multi-center, open-label Phase 3 clinical trial of Vicineum as a monotherapy in patients with bacillus Calmette-Guérin ("BCG")-unresponsive non-muscle invasive bladder cancer ("NMIBC") (the "VISTA Trial"). The VISTA Trial completed enrollment in April 2018 with a total of 133 patients, and in December 2019, the Company initiated submission of the Biologics License Application ("BLA") for Vicineum to the United States Food and Drug Administration ("FDA") under Rolling Review, which enables individual modules to be submitted and reviewed on an ongoing basis, rather than waiting for all sections to be completed before submission. On December 18, 2020, the Company submitted its completed BLA for Vicineum for the treatment of </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9.5pt;font-weight:400;line-height:120%">BCG-unresponsive</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> NMIBC to the FDA.The Company operates in one segment under the direction of its Chief Executive Officer (chief operating decision maker). The Company was formerly known as Eleven Biotherapeutics, Inc. until its name changed in May 2018.</span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Viventia Acquisition</span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In September 2016, the Company entered into a Share Purchase Agreement with Viventia Bio, Inc., a corporation incorporated under the laws of the Province of Ontario, Canada ("Viventia"), the shareholders of Viventia named therein (the “Selling Shareholders”) and, solely in its capacity as seller representative, Clairmark Investments Ltd., a corporation incorporated under the laws of the Province of Ontario, Canada (“Clairmark”) (the “Share Purchase Agreement”), pursuant to which the Company agreed to and simultaneously completed the acquisition of all of the outstanding capital stock of Viventia from the Selling Shareholders (the “Viventia Acquisition”). In connection with the closing of the Viventia Acquisition, the Company issued 4.0 million shares of its common stock to the Selling Shareholders, which at that time represented approximately 19.9% of the voting power of the Company as of immediately prior to the issuance of such shares. Clairmark is an affiliate of Leslie L. Dan, a director of the Company until his retirement in July 2019.</span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In addition, under the Share Purchase Agreement, the Company is obligated to pay to the Selling Shareholders certain post-closing contingent cash payments upon the achievement of specified milestones and based upon net sales, in each case subject to the terms and conditions set forth in the Share Purchase Agreement, including: (i) a one-time milestone payment of $12.5 million payable upon the first sale of Vicineum (the “Purchased Product”), in the United States; (ii) a one-time milestone payment of $7.0 million payable upon the first sale of the Purchased Product in any one of certain specified European countries; (iii) a one-time milestone payment of $3.0 million payable upon the first sale of the Purchased Product in Japan; and (iv) quarterly earn-out payments equal to 2% of net sales of the Purchased Product during specified earn-out periods. Such earn-out payments are payable with respect to net sales in a country beginning on the date of the first sale in such country and ending on the earlier of (i) December 31, 2033 and (ii) fifteen years after the date of such sale, subject to early termination in certain circumstances if a biosimilar product is on the market in the applicable country (collectively, the "Contingent Consideration"). Under the Share Purchase Agreement, the Company, its affiliates, licensees and subcontractors are required to use commercially reasonable efforts, for the first seven years following the closing of the Viventia Acquisition, to achieve marketing authorizations throughout the world and, during the applicable earn-out period, to commercialize the Purchased Product in the United States, France, Germany, Italy, Spain, United Kingdom, Japan, China and Canada. Certain of these payments are payable to individuals or affiliates of individuals that became employees or members of the Company's board of directors, however as of December 31, 2020, none of these individuals are active employees or members of the Company's board of directors. </span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Liquidity and Going Concern</span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">As of December 31, 2020, the Company had cash and cash equivalents of $52.4 million and an accumulated deficit of $315.9 million. The Company incurred negative cash flows from operating activities of $30.8 million, $37.5 million and $22.8 million for the years ended December 31, 2020, 2019 and 2018, respectively. Since its inception, the Company has received no revenue from sales of its products, and management anticipates that operating losses will continue for the foreseeable future as the Company continues into the follow-up stage of its Phase 3 VISTA Trial of Vicineum for the treatment of </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9.5pt;font-weight:400;line-height:120%">BCG-unresponsive</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> NMIBC, seeks marketing approval from the FDA and, if approved, commercialize Vicineum for the treatment of </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9.5pt;font-weight:400;line-height:120%">BCG-unresponsive</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> NMIBC. The Company has financed its operations to date primarily through private placements of its common stock, preferred stock, common stock warrants and convertible bridge notes, venture debt borrowings, its initial public offering </span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">("IPO"), follow-on public offerings, sales effected in "at-the-market" ("ATM") offerings, </span><span style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">commercialization partnership and </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">out-license agreements. See “Note 10. Stockholders’ Equity” below for information regarding the Company’s recently completed equity financings.</span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Under Accounting Standards Codification ("ASC") Topic 205-40, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Presentation of Financial Statements - Going Concern</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">, management is required at each reporting period to evaluate whether there are conditions and events, considered in the aggregate, that raise substantial doubt about an entity's ability to continue as a going concern within one year after the date that the financial statements are issued. This evaluation initially does not take into consideration the potential mitigating effect of management's plans that have not been fully implemented as of the date the financial statements are issued. When substantial doubt exists, management evaluates whether the mitigating effect of its plans sufficiently alleviates the substantial doubt about the Company's ability to continue as a going concern. The mitigating effect of management's plans, however, is only considered if both (i) it is probable that the plans will be effectively implemented within one year after the date that the financial statements are issued and (ii) it is probable that the plans, when implemented, will mitigate the relevant conditions or events that raise substantial doubt about the entity's ability to continue as a going concern within one year after the date that the financial statements are issued. Generally, to be considered probable of being effectively implemented, the plans must have been approved by the Company's board of directors before the date that the financial statements are issued.</span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The Company's future success is dependent on its ability to develop, obtain marketing approval for and, if approved, commercialize its product candidates, including Vicineum for the treatment of </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9.5pt;font-weight:400;line-height:120%">BCG-unresponsive</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> NMIBC, and ultimately upon its ability to attain profitable operations. In order to commercialize its product candidates, including Vicineum for the treatment of </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9.5pt;font-weight:400;line-height:120%">BCG-unresponsive</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> NMIBC, the Company needs to complete clinical development and comply with comprehensive regulatory requirements. The Company is subject to a number of risks similar to other late-stage clinical companies, including, but not limited to, successful discovery and development, marketing approval and, if approved, commercialization of its product candidates, raising additional capital, development and commercialization by its competitors of new technological innovations, protection of proprietary technology and market acceptance of its products. The successful discovery, development of product candidates, including Vicineum for the treatment of </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9.5pt;font-weight:400;line-height:120%">BCG-unresponsive</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> NMIBC, requires substantial working capital, and management expects to seek additional funds through equity or debt financings or through additional </span><span style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">commercialization partnerships</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">, licensing transactions or other sources. The Company may be unable to obtain equity or debt financings or enter into additional </span><span style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">commercialization partnerships</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> or licensing transactions at favorable terms, or at all. To the extent that the Company raises additional capital through the sale of equity or convertible debt securities, the ownership interests of existing stockholders will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect the rights of existing stockholders. Debt financing, if available, may involve agreements that include liens or other restrictive covenants limiting the Company's ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends. If the Company raises additional funds through government or other third-party funding, strategic </span><span style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">commercialization partnerships</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> and alliances or licensing arrangements, it may have to relinquish valuable rights to its technologies, future revenue streams, research programs or product candidates or grant licenses on terms that may not be favorable. If the Company is unable to raise additional funds when needed, it may be required to implement cost reduction strategies and delay, limit, reduce or terminate its product development or future commercialization efforts or grant rights to develop and market products or product candidates that management would otherwise prefer to develop and market.</span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The Company's management does not believe that its cash and cash equivalents of $52.4 million as of December 31, 2020 is sufficient to fund the Company's current operating plan for at least twelve months after the issuance of these consolidated financial statements. Given the history of significant losses, negative cash flows from operations, limited cash resources currently on hand and dependence by the Company on its ability - about which there can be no certainty - to obtain additional financing to fund its operations after the current cash resources are exhausted, substantial doubt exists about the Company's ability to continue as a going concern. These consolidated financial statements were prepared under the assumption that the Company will continue as a going concern and do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty.</span></div>
CY2020	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	1	segment
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	52400000	USD
CY2020Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	-315900000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-30800000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-37500000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-22800000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	52400000	USD
CY2020	us-gaap	Basis Of Accounting BasisOfAccounting	BASIS OF PRESENTATION<div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The accompanying financial statements have been prepared in accordance with United States generally accepted accounting principles ("GAAP"). Any reference in these notes to applicable guidance is meant to refer to GAAP as found in the ASC and Accounting Standards Updates ("ASUs"), promulgated by the Financial Accounting Standards Board ("FASB").</span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Use of Estimates</span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The preparation of financial statements in accordance with GAAP and the rules and regulations of the United States Securities and Exchange Commission ("SEC") requires the use of estimates and assumptions, based on judgments considered reasonable, which affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. The Company bases its estimates and assumptions on historical experience, known trends and events and various other factors that management believes to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Although management believes its estimates and assumptions are reasonable when made, they are based upon information available at the time they are made. Management evaluates the estimates and assumptions on an ongoing basis and, if necessary, makes adjustments. Due to the risks and uncertainties involved in the Company’s business and evolving market conditions, and given the subjective element of the estimates and assumptions made, actual results may differ from estimated results. The most significant estimates and judgments impact the fair value of intangible assets, goodwill and contingent consideration; income taxes (including the valuation allowance for deferred tax assets); research and development expenses; and going concern considerations.</span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Principles of Consolidation</span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The Company’s consolidated financial statements include the accounts of the Company, its wholly owned subsidiary Viventia and its indirect subsidiaries, Viventia Bio USA Inc. and Viventia Biotech (EU) Limited. All intercompany transactions and balances have been eliminated in consolidation.</span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Foreign Currency Translation</span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The functional currency of the Company and each of its subsidiaries is the U.S. dollar.</span></div>
CY2020	us-gaap	Use Of Estimates UseOfEstimates	Use of EstimatesThe preparation of financial statements in accordance with GAAP and the rules and regulations of the United States Securities and Exchange Commission ("SEC") requires the use of estimates and assumptions, based on judgments considered reasonable, which affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. The Company bases its estimates and assumptions on historical experience, known trends and events and various other factors that management believes to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Although management believes its estimates and assumptions are reasonable when made, they are based upon information available at the time they are made. Management evaluates the estimates and assumptions on an ongoing basis and, if necessary, makes adjustments. Due to the risks and uncertainties involved in the Company’s business and evolving market conditions, and given the subjective element of the estimates and assumptions made, actual results may differ from estimated results. The most significant estimates and judgments impact the fair value of intangible assets, goodwill and contingent consideration; income taxes (including the valuation allowance for deferred tax assets); research and development expenses; and going concern considerations.
CY2020Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	250000	USD
CY2020	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	USD
CY2018	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	USD
CY2019	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	USD
CY2019	us-gaap	Impairment Of Intangible Assets Indefinitelived Excluding Goodwill ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill	0	USD
CY2020	us-gaap	Impairment Of Intangible Assets Indefinitelived Excluding Goodwill ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill	0	USD
CY2020	us-gaap	Number Of Reporting Units NumberOfReportingUnits	1	reporting_unit
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2018	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2019Q1	us-gaap	Operating Lease Liability OperatingLeaseLiability	200000	USD
CY2019Q1	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	200000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0
CY2020Q4	us-gaap	Business Combination Contingent Consideration Liability Noncurrent BusinessCombinationContingentConsiderationLiabilityNoncurrent	99855000	USD
CY2019Q4	us-gaap	Business Combination Contingent Consideration Liability Noncurrent BusinessCombinationContingentConsiderationLiabilityNoncurrent	120020000	USD
CY2019Q4	us-gaap	Business Combination Contingent Consideration Liability Noncurrent BusinessCombinationContingentConsiderationLiabilityNoncurrent	120020000	USD
CY2020Q1	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	-53700000	USD
CY2020Q1	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	66320000	USD
CY2020Q2	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	18480000	USD
CY2020Q2	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	84800000	USD
CY2020Q3	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	18400000	USD
CY2020Q3	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	103200000	USD
CY2020Q4	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	5640000	USD
CY2020Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	108840000	USD
CY2020Q4	us-gaap	Business Combination Contingent Consideration Liability Noncurrent BusinessCombinationContingentConsiderationLiabilityNoncurrent	99855000	USD
CY2020Q4	sesn	License Agreement Royalty Rate LicenseAgreementRoyaltyRate	0.02
CY2019Q4	us-gaap	Business Combination Contingent Consideration Liability Measurement Input BusinessCombinationContingentConsiderationLiabilityMeasurementInput	0.118
CY2020Q1	us-gaap	Business Combination Contingent Consideration Liability Measurement Input BusinessCombinationContingentConsiderationLiabilityMeasurementInput	0.179
CY2020Q2	us-gaap	Business Combination Contingent Consideration Liability Measurement Input BusinessCombinationContingentConsiderationLiabilityMeasurementInput	0.145
CY2020Q3	us-gaap	Business Combination Contingent Consideration Liability Measurement Input BusinessCombinationContingentConsiderationLiabilityMeasurementInput	0.118
CY2020Q4	us-gaap	Business Combination Contingent Consideration Liability Measurement Input BusinessCombinationContingentConsiderationLiabilityMeasurementInput	0.084
CY2020	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	-11800000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	1004000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	996000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	881000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	758000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	123000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	238000	USD
CY2020	us-gaap	Depreciation And Amortization DepreciationAndAmortization	100000	USD
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	200000	USD
CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	200000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	13100000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	13100000	USD
CY2020Q4	sesn	Accrued Research And Development Expense Current AccruedResearchAndDevelopmentExpenseCurrent	1372000	USD
CY2019Q4	sesn	Accrued Research And Development Expense Current AccruedResearchAndDevelopmentExpenseCurrent	3688000	USD
CY2020Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	1892000	USD
CY2019Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	1638000	USD
CY2020Q4	us-gaap	Supplemental Unemployment Benefits Severance Benefits SupplementalUnemploymentBenefitsSeveranceBenefits	0	USD
CY2019Q4	us-gaap	Supplemental Unemployment Benefits Severance Benefits SupplementalUnemploymentBenefitsSeveranceBenefits	378000	USD
CY2020Q4	us-gaap	Accrued Professional Fees Current AccruedProfessionalFeesCurrent	684000	USD
CY2019Q4	us-gaap	Accrued Professional Fees Current AccruedProfessionalFeesCurrent	378000	USD
CY2020Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	25000	USD
CY2019Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	87000	USD
CY2020Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	3973000	USD
CY2019Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	6169000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	301000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	298000	USD
CY2020	us-gaap	Short Term Lease Cost ShortTermLeaseCost	261000	USD
CY2019	us-gaap	Short Term Lease Cost ShortTermLeaseCost	263000	USD
CY2020	us-gaap	Lease Cost LeaseCost	562000	USD
CY2019	us-gaap	Lease Cost LeaseCost	561000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P1Y9M
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P0Y9M
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.12
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.12
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	162000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	122000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	284000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	13000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	271000	USD
CY2019Q4	sesn	Sale Of Stock Commission Fixed Rate SaleOfStockCommissionFixedRate	0.030
CY2020	us-gaap	Professional Fees ProfessionalFees	200000	USD
CY2019	us-gaap	Professional Fees ProfessionalFees	200000	USD
CY2020Q4	sesn	Stock Issued During Period New Issues Issuance Costs StockIssuedDuringPeriodNewIssuesIssuanceCosts	700000	USD
CY2020	sesn	Stock Issued During Period New Issues Issuance Costs StockIssuedDuringPeriodNewIssuesIssuanceCosts	1200000	USD
CY2019Q2	us-gaap	Sale Of Stock Consideration Received On Transaction SaleOfStockConsiderationReceivedOnTransaction	27800000	USD
CY2019Q2	us-gaap	Sale Of Stock Number Of Shares Issued In Transaction SaleOfStockNumberOfSharesIssuedInTransaction	20400000	shares
CY2020Q2	us-gaap	Class Of Warrant Or Right Number Of Securities Called By Warrants Or Rights ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights	20400000	shares
CY2020Q2	sesn	Common Stock And Warrant Or Rights Price Per Share CommonStockAndWarrantOrRightsPricePerShare	1.47
CY2020Q2	us-gaap	Class Of Warrant Or Right Exercise Price Of Warrants Or Rights1 ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1	1.47
CY2020Q2	us-gaap	Warrants And Rights Outstanding Term WarrantsAndRightsOutstandingTerm	P1Y
CY2018Q2	us-gaap	Sale Of Stock Consideration Received On Transaction SaleOfStockConsiderationReceivedOnTransaction	41900000	USD
CY2018Q2	us-gaap	Sale Of Stock Number Of Shares Issued In Transaction SaleOfStockNumberOfSharesIssuedInTransaction	25600000	shares
CY2018Q2	us-gaap	Sale Of Stock Price Per Share SaleOfStockPricePerShare	1.80
CY2018Q1	us-gaap	Sale Of Stock Consideration Received On Transaction SaleOfStockConsiderationReceivedOnTransaction	9000000.0	USD
CY2018Q1	us-gaap	Sale Of Stock Number Of Shares Issued In Transaction SaleOfStockNumberOfSharesIssuedInTransaction	8000000.0	shares
CY2018Q1	us-gaap	Sale Of Stock Price Per Share SaleOfStockPricePerShare	1.13
CY2018Q1	us-gaap	Class Of Warrant Or Right Number Of Securities Called By Warrants Or Rights ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights	8000000.0	shares
CY2018Q1	sesn	Class Of Warrant Or Right Price Per Share ClassOfWarrantOrRightPricePerShare	0.125
CY2018Q1	us-gaap	Class Of Warrant Or Right Exercise Price Of Warrants Or Rights1 ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1	1.20
CY2018Q1	us-gaap	Warrants And Rights Outstanding Term WarrantsAndRightsOutstandingTerm	P5Y
CY2020Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	5000000.0	shares
CY2020Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.001
CY2020Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2019Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2020Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2019Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	200000000.0	shares
CY2020Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.001
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	140400000	shares
CY2020Q4	us-gaap	Shares Outstanding SharesOutstanding	140400000	shares
CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	106800000	shares
CY2019Q4	us-gaap	Shares Outstanding SharesOutstanding	106800000	shares
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	140450000	shares
CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	106801000	shares
CY2020Q4	us-gaap	Common Stock Capital Shares Reserved For Future Issuance CommonStockCapitalSharesReservedForFutureIssuance	10147000	shares
CY2019Q4	us-gaap	Common Stock Capital Shares Reserved For Future Issuance CommonStockCapitalSharesReservedForFutureIssuance	6236000	shares
CY2020Q4	sesn	Common Stock Shares Issued And Reserved For Future CommonStockSharesIssuedAndReservedForFuture	157707000	shares
CY2019Q4	sesn	Common Stock Shares Issued And Reserved For Future CommonStockSharesIssuedAndReservedForFuture	144713000	shares
CY2019Q4	us-gaap	Class Of Warrant Or Right Outstanding ClassOfWarrantOrRightOutstanding	22895000	shares
CY2020	sesn	Class Of Warrant Or Right Issued During The Period ClassOfWarrantOrRightIssuedDuringThePeriod	0	shares
CY2020	sesn	Stock Issued During Period Shares Exercise Of Warrants StockIssuedDuringPeriodSharesExerciseOfWarrants	238000	shares
CY2020	sesn	Class Of Warrant Or Right Number Of Expirations During The Period ClassOfWarrantOrRightNumberOfExpirationsDuringThePeriod	20410000	shares
CY2020Q4	us-gaap	Class Of Warrant Or Right Outstanding ClassOfWarrantOrRightOutstanding	2247000	shares
CY2020	us-gaap	Proceeds From Warrant Exercises ProceedsFromWarrantExercises	100000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Warrant Issued AdjustmentsToAdditionalPaidInCapitalWarrantIssued	1100000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Warrant Issued AdjustmentsToAdditionalPaidInCapitalWarrantIssued	1100000	USD
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	12394000	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	29131000	shares
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	13200000	shares
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	1757000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	1237000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	1283000	USD
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	2696000	shares
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	3.16
CY2017	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P8Y6M18D
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	146000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	3546000	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	1.71
CY2018	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	439000	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	0.62
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	1861000	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	3.21
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	3942000	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	2.12
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P9Y1M20D
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	57000	USD
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	3986000	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	1.02
CY2019	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	90000	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	1.10
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	1602000	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	1.78
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	6236000	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	1.52
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P8Y9M29D
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	358000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	4044000	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	0.87
CY2020	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	12000	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	1.13
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	121000	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	1.04
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	10147000	shares
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P6Y
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	1.26
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P8Y6M
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	3160000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	4228000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	1.63
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P7Y10M6D
CY2020Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	931000	USD
CY2020Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Stock Options EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions	3600000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	0.87
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	0.69
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	1.14
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	500000	USD
CY2020	sesn	Sharebased Compensation Arrangementby Sharebased Payment Award Fair Value Assumptions Fair Value Of Common Stock SharebasedCompensationArrangementbySharebasedPaymentAwardFairValueAssumptionsFairValueOfCommonStock	0.56
CY2019	sesn	Sharebased Compensation Arrangementby Sharebased Payment Award Fair Value Assumptions Fair Value Of Common Stock SharebasedCompensationArrangementbySharebasedPaymentAwardFairValueAssumptionsFairValueOfCommonStock	1.02
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CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0
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CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-20952000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-107500000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-33693000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	0	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	0	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	0	USD
CY2020	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	1445000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	0	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	0	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	1445000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	0	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	0	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	0	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	0	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	0	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	0	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	0	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	0	USD
CY2020	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	0	USD
CY2019	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	0	USD
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	0	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	0	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	0	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	0	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1445000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	0	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	0	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
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CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
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CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.069
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	-0.377
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	-0.079
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	-0.181
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-0.069
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	57935000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	50727000	USD
CY2020Q4	us-gaap	Deferred Tax Assets In Process Research And Development DeferredTaxAssetsInProcessResearchAndDevelopment	3787000	USD
CY2019Q4	us-gaap	Deferred Tax Assets In Process Research And Development DeferredTaxAssetsInProcessResearchAndDevelopment	4385000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Other DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsOther	3811000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Other DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsOther	2464000	USD
CY2020Q4	sesn	Deferred Tax Assets Capitalized Start Up Costs DeferredTaxAssetsCapitalizedStartUpCosts	70000	USD
CY2019Q4	sesn	Deferred Tax Assets Capitalized Start Up Costs DeferredTaxAssetsCapitalizedStartUpCosts	91000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	28000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	57000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Capitalized Research And Development Costs DeferredTaxLiabilitiesDeferredExpenseCapitalizedResearchAndDevelopmentCosts	12528000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	65631000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	57724000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Capitalized Research And Development Costs DeferredTaxLiabilitiesDeferredExpenseCapitalizedResearchAndDevelopmentCosts	12528000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	0	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	0	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	12528000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	12528000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	65631000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	57724000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	12528000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	12528000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	65600000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	57700000	USD
CY2020	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	7900000	USD
CY2020Q4	sesn	Operating Loss Carryforwards Decrease OperatingLossCarryforwardsDecrease	800000	USD

Files In Submission

Name	View Source	Status
0001485003-21-000044-index-headers.html	Edgar Link	pending
0001485003-21-000044-index.html	Edgar Link	pending
0001485003-21-000044.txt	Edgar Link	pending
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Show.js	Edgar Link	pending

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$CARM
Carisma Therapeutics Inc Stock $carm

2019 Q4 Form 10-K Financial Statement

#000148500321000044 Filed on March 15, 2021

Income Statement

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Facts In Submission

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$CARM Carisma Therapeutics Inc Stock $carm

2019 Q4 Form 10-K Financial Statement

#000148500321000044 Filed on March 15, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CARM
Carisma Therapeutics Inc Stock $carm