$MRSN
Mersana Therapeutics, Inc. Stock $mrsn

$mrsn Overview Financials Valuation SEC Filings Company Website

2021 Q2 Form 10-Q Financial Statement

#000162828021016000 Filed on August 06, 2021

Income Statement

Concept	2021 Q2	2020 Q4	2020 Q2
Revenue	$11.00K	$10.00K	$796.0K
YoY Change	-98.62%	-76.19%	294.06%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin	$8.883M	$5.910M	$5.170M
YoY Change	71.82%	40.38%	23.39%
% of Gross Profit
Research & Development	$31.96M	$22.86M	$15.41M
YoY Change	107.32%	83.89%	11.96%
% of Gross Profit
Depreciation & Amortization	$202.0K	$260.0K	$240.0K
YoY Change	-15.83%	-10.34%	-22.58%
% of Gross Profit
Operating Expenses	$40.84M	$28.77M	$20.58M
YoY Change	98.4%	72.89%	14.62%
Operating Profit
YoY Change
Interest Expense	$95.00K	$92.00K	$87.00K
YoY Change	9.2%	5.75%	117.5%
% of Operating Profit
Other Income/Expense, Net	-$86.00K	-$82.00K	$2.000K
YoY Change	-4400.0%	-123.16%	-99.71%
Pretax Income	-$40.91M	-$28.84M	-$19.79M
YoY Change	106.74%	77.48%	15.93%
Income Tax
% Of Pretax Income
Net Earnings	-$40.90M	-$28.84M	-$19.79M
YoY Change	106.71%	77.55%	15.9%
Net Earnings / Revenue	-371818.18%	-288440.0%	-2485.68%
Basic Earnings Per Share	-$0.59	-$0.42	-$0.33
Diluted Earnings Per Share	-$0.59	-$0.42	-$0.33
COMMON SHARES
Basic Shares Outstanding	69.62M shares	68.50M shares	60.75M shares
Diluted Shares Outstanding	69.62M shares		60.75M shares

Balance Sheet

Concept	2021 Q2	2020 Q4	2020 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments	$227.4M	$255.1M	$291.4M
YoY Change	-21.96%	155.63%	127.28%
Cash & Equivalents	$227.4M	$255.1M	$288.4M
Short-Term Investments		$0.00	$3.002M
Other Short-Term Assets	$6.043M	$3.500M	$3.500M
YoY Change	72.66%	133.33%	9.38%
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets	$233.4M	$258.6M	$294.9M
YoY Change	-20.85%	155.2%	124.09%
LONG-TERM ASSETS
Property, Plant & Equipment	$15.65M	$1.730M	$1.768M
YoY Change	785.01%	-20.06%	-71.94%
Goodwill
YoY Change
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets	$4.607M	$2.153M	$2.103M
YoY Change	119.07%	48.18%	40.2%
Total Long-Term Assets	$20.25M	$14.82M	$15.61M
YoY Change	29.73%	138.44%	100.17%
TOTAL ASSETS
Total Short-Term Assets	$233.4M	$258.6M	$294.9M
Total Long-Term Assets	$20.25M	$14.82M	$15.61M
Total Assets	$253.7M	$273.4M	$310.5M
YoY Change	-18.3%	154.23%	122.75%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$10.65M	$8.340M	$7.159M
YoY Change	48.72%	14.31%	10.14%
Accrued Expenses	$23.38M	$16.15M	$8.372M
YoY Change	179.3%	79.68%	-29.05%
Deferred Revenue	$3.966M	$3.987M	$4.008M
YoY Change	-1.05%	-17.2%
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$173.0K	$0.00	$1.667M
YoY Change	-89.62%	-100.0%	1567.0%
Total Short-Term Liabilities	$40.47M	$30.00M	$22.42M
YoY Change	80.49%	24.65%	-6.18%
LONG-TERM LIABILITIES
Long-Term Debt	$5.027M	$4.977M	$3.263M
YoY Change	54.06%	18.47%	-36.02%
Other Long-Term Liabilities	$288.0K	$174.0K	$225.0K
YoY Change	28.0%	-36.73%	-87.5%
Total Long-Term Liabilities	$5.315M	$5.151M	$3.488M
YoY Change	52.38%	15.08%	-49.45%
TOTAL LIABILITIES
Total Short-Term Liabilities	$40.47M	$30.00M	$22.42M
Total Long-Term Liabilities	$5.315M	$5.151M	$3.488M
Total Liabilities	$58.17M	$45.31M	$36.95M
YoY Change	57.42%	55.06%	19.59%
SHAREHOLDERS EQUITY
Retained Earnings	-$356.0M	-$280.4M	-$229.1M
YoY Change	55.41%	45.77%
Common Stock	$551.5M	$508.5M	$502.6M
YoY Change	9.73%	87.87%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$195.5M	$228.1M	$273.6M
YoY Change
Total Liabilities & Shareholders Equity	$253.7M	$273.4M	$310.5M
YoY Change	-18.3%	154.23%	122.75%

Cashflow Statement

Concept	2021 Q2	2020 Q4	2020 Q2
OPERATING ACTIVITIES
Net Income	-$40.90M	-$28.84M	-$19.79M
YoY Change	106.71%	77.55%	15.9%
Depreciation, Depletion And Amortization	$202.0K	$260.0K	$240.0K
YoY Change	-15.83%	-10.34%	-22.58%
Cash From Operating Activities	-$34.47M	-$17.32M	-$15.93M
YoY Change	116.38%	37.79%	12.26%
INVESTING ACTIVITIES
Capital Expenditures	-$337.0K	-$180.0K	-$20.00K
YoY Change	1585.0%		-90.48%
Acquisitions
YoY Change
Other Investing Activities	$0.00	$0.00	$15.00M
YoY Change	-100.0%	-100.0%	-225.52%
Cash From Investing Activities	-$337.0K	-$190.0K	$14.97M
YoY Change	-102.25%	-101.15%	-223.11%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	33.92M	1.660M	228.9M
YoY Change	-85.18%	621.74%	4235.04%
NET CHANGE
Cash From Operating Activities	-34.47M	-17.32M	-15.93M
Cash From Investing Activities	-337.0K	-190.0K	14.97M
Cash From Financing Activities	33.92M	1.660M	228.9M
Net Change In Cash	-889.0K	-15.85M	227.9M
YoY Change	-100.39%	-481.01%	-1181.78%
FREE CASH FLOW
Cash From Operating Activities	-$34.47M	-$17.32M	-$15.93M
Capital Expenditures	-$337.0K	-$180.0K	-$20.00K
Free Cash Flow	-$34.13M	-$17.14M	-$15.91M
YoY Change	114.54%	36.36%	13.81%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020Q4	us-gaap	Security Deposit SecurityDeposit	321000	USD
	dei	Entity Central Index Key EntityCentralIndexKey	0001442836
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	04-3562403
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2021
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q2
	dei	Amendment Flag AmendmentFlag	false
	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2021-06-30
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity File Number EntityFileNumber	001-38129
	dei	Entity Registrant Name EntityRegistrantName	Mersana Therapeutics, Inc.
	dei	Entity Address Address Line1 EntityAddressAddressLine1	840 Memorial Drive
	dei	Entity Address City Or Town EntityAddressCityOrTown	Cambridge
	dei	Entity Address State Or Province EntityAddressStateOrProvince	MA
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	02139
	dei	City Area Code CityAreaCode	617
	dei	Local Phone Number LocalPhoneNumber	498-0020
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	dei	Trading Symbol TradingSymbol	MRSN
	dei	Security Exchange Name SecurityExchangeName	NASDAQ
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Entity Small Business EntitySmallBusiness	false
	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
	dei	Entity Shell Company EntityShellCompany	false
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CY2021Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	227388000	USD
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CY2020Q4	us-gaap	Assets Current AssetsCurrent	258580000	USD
CY2021Q2	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset After Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization	1901000	USD
CY2021Q2	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	23383000	USD
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CY2020Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	8340000	USD
CY2021Q2	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	13746000	USD
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CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	1437000	USD
CY2021Q2	us-gaap	Long Term Debt Current LongTermDebtCurrent	173000	USD
CY2020Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	0	USD
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CY2020Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	93000	USD
CY2021Q2	us-gaap	Liabilities Current LiabilitiesCurrent	40471000	USD
CY2020Q4	us-gaap	Liabilities Current LiabilitiesCurrent	30003000	USD
CY2021Q2	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	12543000	USD
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	10158000	USD
CY2021Q2	us-gaap	Long Term Debt LongTermDebt	4870000	USD
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CY2020Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
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CY2020Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
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CY2021Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	11000	USD
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CY2021Q2	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	31955000	USD
CY2020Q2	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	15413000	USD
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	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	59370000	USD
	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	27632000	USD
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	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	16090000	USD
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	us-gaap	Operating Expenses OperatingExpenses	75460000	USD
	us-gaap	Operating Expenses OperatingExpenses	37738000	USD
CY2021Q2	us-gaap	Investment Income Interest InvestmentIncomeInterest	9000	USD
CY2020Q2	us-gaap	Investment Income Interest InvestmentIncomeInterest	89000	USD
	us-gaap	Investment Income Interest InvestmentIncomeInterest	21000	USD
	us-gaap	Investment Income Interest InvestmentIncomeInterest	394000	USD
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	us-gaap	Interest Expense InterestExpense	188000	USD
	us-gaap	Interest Expense InterestExpense	175000	USD
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	us-gaap	Net Income Loss NetIncomeLoss	-75606000	USD
	us-gaap	Net Income Loss NetIncomeLoss	-36712000	USD
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CY2020Q4	us-gaap	Net Income Loss NetIncomeLoss	-28844000	USD
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CY2021Q1	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	764000	USD
CY2021Q1	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	259000	USD
CY2021Q1	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	4039000	USD
CY2021Q1	us-gaap	Net Income Loss NetIncomeLoss	-34693000	USD
CY2021Q1	us-gaap	Stockholders Equity StockholdersEquity	197938000	USD
CY2021Q2	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	202000	USD
CY2021Q2	us-gaap	Adjustments To Additional Paid In Capital Share Based Compensation Employee Stock Purchase Program Requisite Service Period Recognition AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationEmployeeStockPurchaseProgramRequisiteServicePeriodRecognition	417000	USD
CY2021Q2	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	4582000	USD
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	-40913000	USD
CY2021Q2	us-gaap	Stockholders Equity StockholdersEquity	195513000	USD
	us-gaap	Profit Loss ProfitLoss	-75606000	USD
	us-gaap	Profit Loss ProfitLoss	-36712000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	432000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	494000	USD
	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	0	USD
	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	86000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	8621000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	3265000	USD
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-77000	USD
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-74000	USD
	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	2418000	USD
	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	163000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	2296000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	650000	USD
	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	2270000	USD
	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-377000	USD
	us-gaap	Increase Decrease In Accrued Liabilities IncreaseDecreaseInAccruedLiabilities	7139000	USD
	us-gaap	Increase Decrease In Accrued Liabilities IncreaseDecreaseInAccruedLiabilities	-2349000	USD
	mrsn	Increase Decrease In Operating Lease Assets IncreaseDecreaseInOperatingLeaseAssets	972000	USD
	mrsn	Increase Decrease In Operating Lease Assets IncreaseDecreaseInOperatingLeaseAssets	836000	USD
	us-gaap	Increase Decrease In Operating Lease Liability IncreaseDecreaseInOperatingLeaseLiability	-660000	USD
	us-gaap	Increase Decrease In Operating Lease Liability IncreaseDecreaseInOperatingLeaseLiability	-706000	USD
	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	-21000	USD
	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	-807000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-61490000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-37181000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	0	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	34500000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	447000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	90000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-447000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	34410000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	966000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	1415000	USD
	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	417000	USD
	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	333000	USD
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	259000	USD
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	0	USD
	mrsn	Proceeds From Debt Net Issuance Costs ProceedsFromDebtNetIssuanceCosts	0	USD
	mrsn	Proceeds From Debt Net Issuance Costs ProceedsFromDebtNetIssuanceCosts	-180000	USD
	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	74000	USD
	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	58000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	34388000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	228796000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-27549000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	226025000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	255415000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	62672000	USD
CY2021Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	227866000	USD
CY2020Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	288697000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	46000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	10000	USD
	mrsn	Equity Issuance Costs Incurred During Noncash Or Part Noncash Transaction EquityIssuanceCostsIncurredDuringNoncashOrPartNoncashTransaction	51000	USD
	mrsn	Equity Issuance Costs Incurred During Noncash Or Part Noncash Transaction EquityIssuanceCostsIncurredDuringNoncashOrPartNoncashTransaction	321000	USD
	us-gaap	Interest Paid Net InterestPaidNet	122000	USD
	us-gaap	Interest Paid Net InterestPaidNet	113000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	3783000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	9980000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	213000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	0	USD
	us-gaap	Net Income Loss NetIncomeLoss	-75606000	USD
	us-gaap	Net Income Loss NetIncomeLoss	-36712000	USD
CY2021Q2	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	-356025000	USD
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CY2020Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	288376000	USD
CY2020Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	321000	USD
CY2021Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	227866000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	62672000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	255094000	USD
CY2021Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	227388000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	62351000	USD
CY2021Q2	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	478000	USD
CY2019Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	321000	USD
CY2020Q2	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	321000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	255415000	USD
CY2020Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	288697000	USD
CY2021Q2	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	4607000	USD
CY2020Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	2153000	USD
CY2021Q2	us-gaap	Retainage Deposit RetainageDeposit	4129000	USD
CY2021Q2	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	9087330	shares
CY2020Q4	us-gaap	Retainage Deposit RetainageDeposit	1832000	USD
CY2021Q2	us-gaap	Security Deposit SecurityDeposit	478000	USD
CY2020Q4	us-gaap	Security Deposit SecurityDeposit	321000	USD
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	9087330	shares
CY2020Q2	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	6728105	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	6728105	shares
	mrsn	Contract With Customer Liability Decrease ContractWithCustomerLiabilityDecrease	807000	USD
CY2020Q2	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	4008000	USD
CY2020Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	0	USD
CY2021Q2	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	0	USD
CY2020Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	3987000	USD
	mrsn	Contract With Customer Liability Increase ContractWithCustomerLiabilityIncrease	0	USD
	mrsn	Contract With Customer Liability Decrease ContractWithCustomerLiabilityDecrease	21000	USD
CY2021Q2	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	3966000	USD
CY2019Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	0	USD
CY2020Q2	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	0	USD
CY2019Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	4815000	USD
	mrsn	Contract With Customer Liability Increase ContractWithCustomerLiabilityIncrease	0	USD
CY2021Q2	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	11000	USD
CY2020Q2	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	796000	USD
	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	21000	USD
	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	807000	USD
CY2021Q2	us-gaap	Contract With Customer Performance Obligation Satisfied In Previous Period ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod	0	USD
CY2020Q2	us-gaap	Contract With Customer Performance Obligation Satisfied In Previous Period ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod	0	USD
	us-gaap	Contract With Customer Performance Obligation Satisfied In Previous Period ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod	0	USD
	us-gaap	Contract With Customer Performance Obligation Satisfied In Previous Period ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod	0	USD
CY2021Q2	mrsn	Accrued Preclinical And Clinical Expenses Current AccruedPreclinicalAndClinicalExpensesCurrent	17675000	USD
CY2020Q4	mrsn	Accrued Preclinical And Clinical Expenses Current AccruedPreclinicalAndClinicalExpensesCurrent	9902000	USD
CY2021Q2	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	4555000	USD
CY2020Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	5412000	USD
CY2021Q2	mrsn	Accrued Professional Fees And Insurance Current AccruedProfessionalFeesAndInsuranceCurrent	1030000	USD
CY2020Q4	mrsn	Accrued Professional Fees And Insurance Current AccruedProfessionalFeesAndInsuranceCurrent	757000	USD
CY2021Q2	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	123000	USD
CY2020Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	75000	USD
CY2021Q2	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	23383000	USD
CY2020Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	16146000	USD
CY2021Q2	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	5200000	USD
CY2021Q2	us-gaap	Long Term Debt Current LongTermDebtCurrent	173000	USD
CY2021Q2	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	5027000	USD
CY2021Q2	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	214000	USD
CY2021Q2	us-gaap	Debt Instrument Unamortized Premium DebtInstrumentUnamortizedPremium	57000	USD
CY2021Q2	us-gaap	Long Term Debt LongTermDebt	4870000	USD
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod	270082	shares
CY2021Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal Remainder Of Fiscal Year LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear	0	USD
CY2021Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	1213000	USD
CY2021Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	2080000	USD
CY2021Q2	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	1907000	USD
CY2021Q2	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	5200000	USD
CY2021Q2	us-gaap	Interest Expense Debt InterestExpenseDebt	89000	USD
CY2020Q2	us-gaap	Interest Expense Debt InterestExpenseDebt	51000	USD
	us-gaap	Interest Expense Debt InterestExpenseDebt	177000	USD
	us-gaap	Interest Expense Debt InterestExpenseDebt	102000	USD
CY2021Q2	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	25000000	shares
CY2021Q2	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2013	mrsn	Class Of Warrant Or Right Securities Called By Warrants Or Rights Number Issued ClassOfWarrantOrRightSecuritiesCalledByWarrantsOrRightsNumberIssued	129491	shares
CY2013Q4	us-gaap	Class Of Warrant Or Right Exercise Price Of Warrants Or Rights1 ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1	0.05
CY2013	mrsn	Contractual Life Of Warrants ContractualLifeOfWarrants	P10Y
CY2021Q2	us-gaap	Class Of Warrant Or Right Number Of Securities Called By Warrants Or Rights ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights	39474	shares
	us-gaap	Common Stock Voting Rights CommonStockVotingRights	The holders of the common stock are entitled to one vote for each share held.
CY2021Q2	us-gaap	Common Stock Capital Shares Reserved For Future Issuance CommonStockCapitalSharesReservedForFutureIssuance	9087330	shares
CY2020Q4	us-gaap	Common Stock Capital Shares Reserved For Future Issuance CommonStockCapitalSharesReservedForFutureIssuance	6869189	shares
CY2021Q2	us-gaap	Common Stock Capital Shares Reserved For Future Issuance CommonStockCapitalSharesReservedForFutureIssuance	9087330	shares
CY2020Q4	us-gaap	Common Stock Capital Shares Reserved For Future Issuance CommonStockCapitalSharesReservedForFutureIssuance	6869189	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	6112948	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	7.84
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	2325657	shares
	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	19.27
	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	190978	shares
	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	5.06
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	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice	9.35
CY2021Q2	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	7977545	shares
CY2021Q2	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	11.19
CY2021Q2	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	3548386	shares
CY2021Q2	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	6.07
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CY2021Q2	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	4582000	USD
CY2020Q2	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	1656000	USD
	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	8621000	USD
	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	3265000	USD
CY2021Q2	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	4582000	USD
CY2020Q2	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	1656000	USD
	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	8621000	USD
	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	3265000	USD
CY2021Q2	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.010
CY2020Q2	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.005
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CY2021Q2	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0
CY2021Q2	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.83
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CY2020Q2	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0
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	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0
CY2021Q2	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y11M19D
CY2020Q2	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P6Y
	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P6Y14D
	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P6Y14D
CY2020Q2	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.80
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.83
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.70
CY2021Q2	mrsn	Increase Decrease In Operating Lease Right Of Use Asset IncreaseDecreaseInOperatingLeaseRightOfUseAsset	3783000	USD
CY2021Q2	us-gaap	Increase Decrease In Operating Lease Liability IncreaseDecreaseInOperatingLeaseLiability	3783000	USD
CY2021Q2	us-gaap	Security Deposit SecurityDeposit	478000	USD
CY2021Q2	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	121000	USD
CY2021Q2	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	0	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	213000	USD
CY2021Q2	us-gaap	Lessee Operating Lease Liability Payments Remainder Of Fiscal Year LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear	1915000	USD
CY2021Q2	us-gaap	Finance Lease Liability Payments Remainder Of Fiscal Year FinanceLeaseLiabilityPaymentsRemainderOfFiscalYear	82000	USD
CY2021Q2	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	3795000	USD
CY2021Q2	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	128000	USD
CY2021Q2	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	3909000	USD
CY2021Q2	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	4027000	USD
CY2021Q2	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	60000	USD
CY2021Q2	mrsn	Lessee Operating Lease Liability Payments Due Year Four And After Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFourAndAfterYearFour	5457000	USD
CY2021Q2	mrsn	Finance Lease Liability Payments Due Year Four And After Year Four FinanceLeaseLiabilityPaymentsDueYearFourAndAfterYearFour	56000	USD
CY2021Q2	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	19103000	USD
CY2021Q2	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	447000	USD
CY2021Q2	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	4387000	USD
CY2021Q2	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	30000	USD
CY2021Q2	us-gaap	Operating Lease Liability OperatingLeaseLiability	14716000	USD
CY2021Q2	us-gaap	Finance Lease Liability FinanceLeaseLiability	417000	USD

Files In Submission

Name	View Source	Status
0001628280-21-016000-index-headers.html	Edgar Link	pending
0001628280-21-016000-index.html	Edgar Link	pending
0001628280-21-016000.txt	Edgar Link	pending
0001628280-21-016000-xbrl.zip	Edgar Link	pending
exhibit10110-q2021q2.htm	Edgar Link	pending
exhibit31110-qfy2021q2.htm	Edgar Link	pending
exhibit31210-qfy2021q2.htm	Edgar Link	pending
exhibit32110-qfy2021q2.htm	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
mrsn-20210630.htm	Edgar Link	pending
mrsn-20210630.xsd	Edgar Link	pending
mrsn-20210630_cal.xml	Edgar Link	unprocessable
mrsn-20210630_def.xml	Edgar Link	unprocessable
mrsn-20210630_htm.xml	Edgar Link	completed
mrsn-20210630_lab.xml	Edgar Link	unprocessable
mrsn-20210630_pre.xml	Edgar Link	unprocessable
R1.htm	Edgar Link	pending
R10.htm	Edgar Link	pending
R11.htm	Edgar Link	pending
R12.htm	Edgar Link	pending
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R6.htm	Edgar Link	pending
R7.htm	Edgar Link	pending
R8.htm	Edgar Link	pending
R9.htm	Edgar Link	pending
report.css	Edgar Link	pending
Show.js	Edgar Link	pending

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$MRSN
Mersana Therapeutics, Inc. Stock $mrsn

2021 Q2 Form 10-Q Financial Statement

#000162828021016000 Filed on August 06, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$MRSN Mersana Therapeutics, Inc. Stock $mrsn

2021 Q2 Form 10-Q Financial Statement

#000162828021016000 Filed on August 06, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$MRSN
Mersana Therapeutics, Inc. Stock $mrsn