0001213900-21-058660 | 10-Q | XBRL Viewer

Condensed Consolidated Balance Sheet Components (Details) - Schedule of accrued expenses and other current liabilities - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Schedule of accrued expenses and other current liabilities [Abstract]
Research and development accrued expenses	$ 1,709	$ 338
Reverse Recapitalization accrued expenses	621
License option liability, current	$ 400	$ 400

Condensed Consolidated Balance Sheet Components (Details) - Schedule of other non-current liabilities - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Schedule of other non-current liabilities [Abstract]
Restricted stock liability	$ 46	$ 53

Cirm Grant (Details) - USD ($) $ in Millions	1 Months Ended	9 Months Ended
Cirm Grant (Details) - USD ($) $ in Millions	Mar. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Cirm Grant Disclosure [Abstract]
CIRM fund technology		$ 1.0
Other receivables milestone			$ 0.6
Other long-term liabilities		$ 0.6	$ 0.6
Received aggregate from CIRM	$ 0.6

Reverse Recapitalization (Details) $ in Millions	9 Months Ended
Reverse Recapitalization (Details) $ in Millions	Sep. 30, 2021 USD ($) shares
Reverse Recapitalization (Details) [Line Items]
Common stock exercised (in Shares) \| shares	9,262,099
Aggregate payments	$ 92.7
Investors shares (in Shares) \| shares	10,000,000
Gross proceeds	$ 100.0
Business combination description	each share of Old Jasper common stock and Old Jasper redeemable convertible preferred stock outstanding immediately prior to the closing was automatically cancelled, extinguished and converted into the number of shares of the Company’s common stock or, in certain circumstances, the Company’s non-voting common stock, based on Old Jasper’s equity value of $275.0 million divided by $10.00. The exchange ratio agreed between the parties was one-for-0.282378 share of the Company’s common stock for all Old Jasper stockholders, except for Amgen Inc. (“Amgen”).
Convertible preferred stock shares (in Shares) \| shares	2,200,000
Business combination description	(i) the Sponsor forfeited 200,000 shares of AMHC’s Class B Common Stock, (ii) each share of AMHC’s Class B common stock outstanding was converted into one share of AMHC’s Class A Common Stock, and (iii) following such conversion, an aggregate of 13,037,901 shares of AMHC’s Class A Common Stock (inclusive of 10,000,000 shares of AMHC’s Class A Common Stock that were issued to the PIPE Investors) was converted into an equivalent number of shares of the Company’s voting common stock. In accordance with the Sponsor Support Agreement, 1,050,000 shares received by the Sponsor were placed in escrow and will be released upon meeting triggering events as defined in the agreement and as described in Note 8 below.
Common stock voting outstanding (in Shares) \| shares	36,520,288
Common stock non-voting outstanding (in Shares) \| shares	1,296,022
Net proceeds	$ 95.3
Cash held in trust account	5.5
Cash received	100.0
Warrant liability	7.9
Fair value earnout liability	$ 15.0

Stock-Based Compensation (Details) - Schedule of stock option activity $ in Thousands	9 Months Ended
	Sep. 30, 2021 USD ($) shares
Schedule of stock option activity [Abstract]
Shares Available for Grant, Options granted	(145,753)
Number of Shares, Options exercised	(285,046)
Shares Available for Grant, Options cancelled/forfeited	122,724
Weighted - Average Remaining Contractual Life (Years), at ending	9 years 21 days
Weighted - Average Remaining Contractual Life (Years), Exercisable	8 years 8 months 26 days
Aggregate Intrinsic Value, Exercisable (in Dollars) \| $	$ 13,642

Significant Agreements (Details) - USD ($) $ in Millions	1 Months Ended	9 Months Ended
Significant Agreements (Details) - USD ($) $ in Millions	Nov. 21, 2019	Sep. 30, 2021	May 31, 2021	Jun. 30, 2020
Significant Agreements (Details) [Line Items]
Research and development cost	$ 0.9	$ 1.0
Amount paid for option exercise fee			$ 0.2	$ 0.2
Convertible preferred stock (in Shares)	100
Annual license maintenance fees description		The Company will pay annual license maintenance fees, beginning on the first anniversary of the effective date of the agreement and ending upon the first commercial sale of a product, method, or service in the licensed field of use, as follows: $25,000 for each first and second year, $35,000 for each third and fourth year, and $50,000 at each anniversary thereafter ending upon the first commercial sale.

Common Stock (Details) - USD ($) $ in Millions	1 Months Ended	9 Months Ended
Common Stock (Details) - USD ($) $ in Millions	Mar. 31, 2018	Sep. 30, 2021	Sep. 24, 2021
Common Stock (Details) [Line Items]
Shares of voting common stock		36,520,288	23,482,387
Shares of non-voting common stock		1,296,022	1,296,022
Estimated fair value (in Dollars)	$ 0.1
Shares issued of vested months	36 months
Restricted stock liability (in Dollars)		$ 0.1
Unvested shares of common stock		611,818
Recognized expected term		2 years 1 month 6 days

Common Stock (Details) - Schedule of reserved common stock for future issuance - shares	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Schedule of reserved common stock for future issuance [Abstract]
Redeemable convertible preferred stock		15,480,195
Outstanding and issued common stock options	2,721,557	2,983,594
Common stock warrants	4,999,993
Shares available for grant under 2019 Equity Incentive Plan		430,893
Shares available for grant under 2021 Equity Incentive Plan	4,400,000
Shares available for grant under 2021 Employee Stock Purchase Plan	550,000
Total shares of common stock reserved	12,671,550	18,894,682

Fair Value Measurements (Details) - Schedule of financial assets and liabilities $ in Thousands	9 Months Ended
	Sep. 30, 2021 USD ($)
Financial liabilities
Common stock warrant liability

Net Loss Per Share Attributable to Common Stockholders (Details) - Schedule of diluted net loss per share attributable to common stockholders - shares	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Schedule of diluted net loss per share attributable to common stockholders [Abstract]
Unvested restricted common stock	611,818	894,197
Total	3,333,375	15,330,127

Reverse Recapitalization (Details) - Schedule of shares of common stock issued and outstanding	Sep. 30, 2021 shares
Schedule of shares of common stock issued and outstanding [Abstract]
Common stock of AMHC outstanding prior to the Business Combination	12,500,000
Less redemption of AMHC shares	(9,262,099)
Common stock of AMHC	3,037,901
Shares issued in PIPE Financing	10,000,000
Business Combination and PIPE Financing shares	13,037,901
Old Jasper shares	24,778,409
Total shares of common stock immediately after the Business Combination	37,816,310

Redeemable Convertible Preferred Stock (Details)	1 Months Ended
Redeemable Convertible Preferred Stock (Details)	Sep. 24, 2021 shares
Redeemable Convertible Preferred Stock (Details) [Line Items]
Common stock shares investor (in Shares)	1,296,022

Label	Element	Value
SharesWereReservedAndAvailableForGrants	jspr_SharesWereReservedAndAvailableForGrants	4,400,000
SharesWereReservedAndAvailableForGrants	jspr_SharesWereReservedAndAvailableForGrants	550,000
ChangeInFairValueOfDilutiveCommonStockWarrants	jspr_ChangeInFairValueOfDilutiveCommonStockWarrants	$ (450,000)
ChangeInFairValueOfDilutiveCommonStockWarrants	jspr_ChangeInFairValueOfDilutiveCommonStockWarrants	(450,000)
ChangeInFairValueOfDilutiveCommonStockWarrants	jspr_ChangeInFairValueOfDilutiveCommonStockWarrants
ChangeInFairValueOfDilutiveCommonStockWarrants	jspr_ChangeInFairValueOfDilutiveCommonStockWarrants
RedeemableConvertiblePreferredStockCarryingValue	jspr_RedeemableConvertiblePreferredStockCarryingValue	42,978
RedeemableConvertiblePreferredStockCarryingValue	jspr_RedeemableConvertiblePreferredStockCarryingValue	862
RedeemableConvertiblePreferredStockCarryingValue	jspr_RedeemableConvertiblePreferredStockCarryingValue	43,840
InitialFairValueOfEarnoutLiability	jspr_InitialFairValueOfEarnoutLiability	$ 15,020,000
InitialFairValueOfEarnoutLiability	jspr_InitialFairValueOfEarnoutLiability
RedeemableConvertiblePreferredSharesIssuedAndOutstanding	jspr_RedeemableConvertiblePreferredSharesIssuedAndOutstanding	15,480,095
RedeemableConvertiblePreferredSharesIssuedAndOutstanding	jspr_RedeemableConvertiblePreferredSharesIssuedAndOutstanding	100
RedeemableConvertiblePreferredSharesIssuedAndOutstanding	jspr_RedeemableConvertiblePreferredSharesIssuedAndOutstanding	15,480,195
CommonStockRemainOutstandingAndUnexercised	jspr_CommonStockRemainOutstandingAndUnexercised	2,721,557
AccountsPayableAndAccruedExpensesForPurchasesOfPropertyAndEquipment	jspr_AccountsPayableAndAccruedExpensesForPurchasesOfPropertyAndEquipment	$ 108,000
AccountsPayableAndAccruedExpensesForPurchasesOfPropertyAndEquipment	jspr_AccountsPayableAndAccruedExpensesForPurchasesOfPropertyAndEquipment
NoncashLeaseholdImprovements	jspr_NoncashLeaseholdImprovements	1,378,000
NoncashLeaseholdImprovements	jspr_NoncashLeaseholdImprovements
VestingOfFoundersRestrictedStock	jspr_VestingOfFoundersRestrictedStock	8,000
VestingOfFoundersRestrictedStock	jspr_VestingOfFoundersRestrictedStock	9,000
NetProceedsFromReverseRecapitalizationAndPIPEFinancingNetOfAssetsAndLiabilitiesAss	jspr_NetProceedsFromReverseRecapitalizationAndPIPEFinancingNetOfAssetsAndLiabilitiesAss	95,271,000
NetProceedsFromReverseRecapitalizationAndPIPEFinancingNetOfAssetsAndLiabilitiesAss	jspr_NetProceedsFromReverseRecapitalizationAndPIPEFinancingNetOfAssetsAndLiabilitiesAss
LessorAmount	jspr_LessorAmount	300,000
ReverseRecapitalizationRelatedExpensesUnpaidAtPeriodEnd	jspr_ReverseRecapitalizationRelatedExpensesUnpaidAtPeriodEnd	651,000
ReverseRecapitalizationRelatedExpensesUnpaidAtPeriodEnd	jspr_ReverseRecapitalizationRelatedExpensesUnpaidAtPeriodEnd
ImprovementAllowanceDescription	jspr_ImprovementAllowanceDescription	To complete certain leasehold improvements, the lessor agreed to provide the Company a tenant improvement allowance of $1.2 million as well as an option to take an additional allowance of $0.4 million to be repaid over the lease term at an interest rate of 9% per annum, which the Company exercised.
RedeemableConvertiblePreferredStockAggregateLiquidationPreference	jspr_RedeemableConvertiblePreferredStockAggregateLiquidationPreference	41,165
RedeemableConvertiblePreferredStockAggregateLiquidationPreference	jspr_RedeemableConvertiblePreferredStockAggregateLiquidationPreference	41,165
RedeemableConvertiblePreferredStockAggregateLiquidationPreference	jspr_RedeemableConvertiblePreferredStockAggregateLiquidationPreference
ConversionOfRedeemableConvertiblePreferredStockIntoCommonStockInConnectionWithReve	jspr_ConversionOfRedeemableConvertiblePreferredStockIntoCommonStockInConnectionWithReve	$ (66,249,000)
ConversionOfRedeemableConvertiblePreferredStockIntoCommonStockInConnectionWithReve	jspr_ConversionOfRedeemableConvertiblePreferredStockIntoCommonStockInConnectionWithReve
NetLiabilitiesAssumedUponTheClosingOfReversedRecapitalization	jspr_NetLiabilitiesAssumedUponTheClosingOfReversedRecapitalization	(7,222,000)
NetLiabilitiesAssumedUponTheClosingOfReversedRecapitalization	jspr_NetLiabilitiesAssumedUponTheClosingOfReversedRecapitalization
RecognitionOfEarnoutLiability	jspr_RecognitionOfEarnoutLiability	15,020,000
RecognitionOfEarnoutLiability	jspr_RecognitionOfEarnoutLiability
CommonStocksSharesIssued	jspr_CommonStocksSharesIssued	1,050,000
IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash	jspr_IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash	$ 10,750,000
IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash	jspr_IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash	484,000
IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash	jspr_IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash
IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash	jspr_IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash
IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash	jspr_IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash
IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash	jspr_IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash
IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash	jspr_IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash
IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash	jspr_IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash
IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash	jspr_IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash
IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash	jspr_IssuanceOfSeriesA1RedeemableConvertiblePreferredStockForCash
DerivativeLossOnDerivatives	jspr_DerivativeLossOnDerivatives	4,700,000
DerivativeLossOnDerivatives	jspr_DerivativeLossOnDerivatives	6,900,000
DerivativeLossOnDerivatives	jspr_DerivativeLossOnDerivatives	3,500,000
DeferredIssuanceCostsReclassifiedToAdditionalPaidInCapital	jspr_DeferredIssuanceCostsReclassifiedToAdditionalPaidInCapital	4,996,000
DeferredIssuanceCostsReclassifiedToAdditionalPaidInCapital	jspr_DeferredIssuanceCostsReclassifiedToAdditionalPaidInCapital
RecognitionsettlementOfDerivativeTrancheLiability	jspr_RecognitionsettlementOfDerivativeTrancheLiability	(11,659,000)
RecognitionsettlementOfDerivativeTrancheLiability	jspr_RecognitionsettlementOfDerivativeTrancheLiability
PurchaseOfAggregateShares	jspr_PurchaseOfAggregateShares	10,000,000
ChangeInFairValueOfEarnoutLiability	jspr_ChangeInFairValueOfEarnoutLiability	$ (6,226,000)
ChangeInFairValueOfEarnoutLiability	jspr_ChangeInFairValueOfEarnoutLiability	(6,226,000)
ChangeInFairValueOfEarnoutLiability	jspr_ChangeInFairValueOfEarnoutLiability
ChangeInFairValueOfEarnoutLiability	jspr_ChangeInFairValueOfEarnoutLiability
AggregateGrossProceeds	jspr_AggregateGrossProceeds	100,000,000
ChangeInValueOfCommonStockSubjectToPossibleRedemption	jspr_ChangeInValueOfCommonStockSubjectToPossibleRedemption	(3,501,000)
ChangeInValueOfCommonStockSubjectToPossibleRedemption	jspr_ChangeInValueOfCommonStockSubjectToPossibleRedemption	(6,864,000)
ChangeInFairValues	jspr_ChangeInFairValues	7,400,000
EstimatedFairValueOfEarnoutLiability	jspr_EstimatedFairValueOfEarnoutLiability	15,000,000
InitialFairValueOfDerivativeInstrument	jspr_InitialFairValueOfDerivativeInstrument
InitialFairValueOfDerivativeInstrument	jspr_InitialFairValueOfDerivativeInstrument
ContingentEarnoutLiabilitiesDescription	jspr_ContingentEarnoutLiabilitiesDescription	Upon the closing of the Business Combination and pursuant to the Sponsor Support Agreement, the Sponsor agreed to place the Earnout Shares into escrow, which will be released as follows: (a) 250,000 Earnout Shares will be released if, during the period from and after September 24, 2021 until the September 24, 2024 (the “Earnout Period”), over any twenty trading days within any thirty day consecutive trading day period, the volume-weighted average price of the Company’s common stock (the “Applicable VWAP”) is greater than or equal to $11.50, (b) 500,000 Earnout Shares will be released if, during the Earnout Period, the Applicable VWAP is greater than or equal to $15.00, and (c) 300,000 Earnout Shares will be released if, during the Earnout Period, the Applicable VWAP is greater than or equal to $18.00 (the “triggering events”).
CurrentPortionOfLeaseLiability	jspr_CurrentPortionOfLeaseLiability	$ 490,000
DerivativeTrancheLiability	jspr_DerivativeTrancheLiability	8,158,000
DerivativeTrancheLiability	jspr_DerivativeTrancheLiability
SharebasedCompensationArrangementsBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	jspr_SharebasedCompensationArrangementsBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	$ 1,600,000
ValuationMethodology	jspr_ValuationMethodology	Monte Carlo Simulation
ValuationMethodology	jspr_ValuationMethodology	Black–Scholes
PayStanfordNet	jspr_PayStanfordNet	$ 900,000
ConversionOfRedeemableConvertiblePreferredStockIntoCommonStockInConnectionWithTheR	jspr_ConversionOfRedeemableConvertiblePreferredStockIntoCommonStockInConnectionWithTheR	(66,249,000)
ConversionOfRedeemableConvertiblePreferredStockIntoCommonStockInConnectionWithTheR	jspr_ConversionOfRedeemableConvertiblePreferredStockIntoCommonStockInConnectionWithTheR	2,000
ConversionOfRedeemableConvertiblePreferredStockIntoCommonStockInConnectionWithTheR	jspr_ConversionOfRedeemableConvertiblePreferredStockIntoCommonStockInConnectionWithTheR	66,247,000
ConversionOfRedeemableConvertiblePreferredStockIntoCommonStockInConnectionWithTheR	jspr_ConversionOfRedeemableConvertiblePreferredStockIntoCommonStockInConnectionWithTheR	$ 66,249,000
PayStanfordNetTerm	jspr_PayStanfordNetTerm	3 years
UnvestedStockBasedCompensation	jspr_UnvestedStockBasedCompensation	$ 1,800,000
FirstMilestoneAgremment	jspr_FirstMilestoneAgremment	300,000
CommonStockWarrantLiability	jspr_CommonStockWarrantLiability	7,400,000
CommonStockWarrantLiability	jspr_CommonStockWarrantLiability
EarnoutLiability	jspr_EarnoutLiability	8,794,000
EarnoutLiability	jspr_EarnoutLiability
TotalExpenseOnResearchProject	jspr_TotalExpenseOnResearchProject	$ 300,000
LicenseAgreementsDescription	jspr_LicenseAgreementsDescription	on the first anniversary of the effective date of the agreement and ending upon the first commercial sale of a product, method, or service in the licensed field of use, as follows: $25,000 for each first and second year, $35,000 for each third and fourth year, and $50,000 at each anniversary thereafter ending upon the first commercial sale. The Company is also obligated to pay late-stage clinical development milestones and first commercial sales milestone payments of up to $9.0 million in total.