Statement of Financial Position [Abstract]
Assets
Assets [Abstract]
Current assets:
Assets, Current [Abstract]
Cash and cash equivalents
Cash and Cash Equivalents, at Carrying Value
Short-term deposits and investments
Short-term Investments
Restricted cash
Restricted Cash and Cash Equivalents, Current
Accounts receivable
Accounts Receivable, Net, Current
Prepaid expenses and other current assets
Prepaid Expense and Other Assets, Current
Total current assets
Assets, Current
Property and equipment, net
Property, Plant and Equipment, Net
Restricted cash and other deposits
Restricted Cash and Investments, Noncurrent
Other assets
Other Assets, Noncurrent
Total assets
Assets
Liabilities and stockholders’ equity
Liabilities and Equity [Abstract]
Current liabilities:
Liabilities, Current [Abstract]
Accounts payable
Accounts Payable, Current
Accrued expenses
Accrued Liabilities, Current
Loans payable, current portion
Loans Payable, Current
Deferred revenue, current portion
Deferred Revenue, Current
Total current liabilities
Liabilities, Current
Non‑current liabilities:
Other Liabilities, Noncurrent [Abstract]
Deferred rent and lease incentive
Deferred Rent Credit, Noncurrent
Loans payable, net of current portion
Loans Payable, Noncurrent
Deferred revenue, net of current portion
Deferred Revenue, Noncurrent
Total liabilities
Liabilities
Commitments and contingencies (Notes 8 and 13)
Commitments and Contingencies
Stockholders’ equity:
Stockholders' Equity Attributable to Parent [Abstract]
Preferred stock, $0.0001 par value; 10,000,000 shares authorized; no shares issued and outstanding at March 31, 2017 and December 31, 2016, respectively.
Preferred Stock, Value, Issued
Common stock, $0.0001 par value; 200,000,000 shares authorized; 18,552,385 and 18,438,742 shares issued and outstanding as of March 31, 2017 and December 31, 2016, respectively.
Common Stock, Value, Issued
Additional paid-in capital
Additional Paid in Capital
Receivable from stock option exercises
Receivable from Shareholders or Affiliates for Issuance of Capital Stock
Accumulated deficit
Retained Earnings (Accumulated Deficit)
Accumulated other comprehensive loss
Accumulated Other Comprehensive Income (Loss), Net of Tax
Total stockholders’ equity
Stockholders' Equity Attributable to Parent
Total liabilities, redeemable convertible preferred stock and stockholders’ equity
Liabilities and Equity
Equity [Abstract]
Common Stock
Stockholders' Equity Note Disclosure [Text Block]
Revenue Recognition [Abstract]
Schedule of Research and Development Arrangement, Contract to Perform for Others [Table]
Schedule of Research and Development Arrangement, Contract to Perform for Others [Table]
Research and Development Arrangement, Contract to Perform for Others, Type [Axis]
Research and Development Arrangement, Contract to Perform for Others, Type [Axis]
Research and Development Arrangement, Contract to Perform for Others, Type [Domain]
Research and Development Arrangement, Contract to Perform for Others, Type [Domain]
Minpromtorg
Russian Ministry Of Industry And Trade Grant Agreement [Member]
Represents information pertaining to Russian Ministry of industry and trade grant agreement.
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Contract awarded
Grants From Entities Amount Of Grant Award
Represents information pertaining to aggregate amount of grant.
Repayment of funds previously received
Repayment of Grant funding received
The cash outflow of grant funding received
Penalty fee (as a percent)
Penalty Fee,Percentage Of Contract Value
Represents information pertaining to penalty fee as percent of contract value.
Penalty fee
Penalty Fee Amount
Represents information pertaining to penalty fee.
Period to audit expenditure incurred
Period To Audit Expenditure Incurred
Represents information pertaining to period to audit expenditure incurred.
Payments received
Increase Decrease In Contingently Repayable Grant Funding
The increase (decrease) during the reporting period in contingently repayable grant funding that are used in an entity's business.
Revenue recognized
Revenue from Grants
Accounting Policies [Abstract]
Reverse stock split, conversion ratio
Stockholders' Equity Note, Stock Split, Conversion Ratio
Commitments and Contingencies Disclosure [Abstract]
Schedule of Operating Leased Assets [Table]
Schedule of Operating Leased Assets [Table]
Range [Axis]
Range [Axis]
Range [Domain]
Range [Domain]
Maximum
Maximum [Member]
Lease Arrangement, Type [Axis]
Lease Arrangement, Type [Axis]
Lease Arrangement, Type [Domain]
Lease Arrangement, Type [Domain]
Laboratory and office space
Laboratory And Office Space [Member]
Represents information pertaining to laboratory and office space member.
Laboratory and office space agreement amendment
Laboratory And Office Space Agreement Amendment April2015 [Member]
Represents information pertaining to laboratory and office space agreement that was amended in April 2015.
Balance Sheet Location [Axis]
Balance Sheet Location [Axis]
Balance Sheet Location [Domain]
Balance Sheet Location [Domain]
Restricted cash and other deposits
Restricted Cash And Other Deposits [Member]
Represents inforamtion pertaining to restricted cash and other deposits member.
Accrued expenses
Accounts Payable and Accrued Liabilities [Member]
Credit Facility [Axis]
Credit Facility [Axis]
Credit Facility [Domain]
Credit Facility [Domain]
Letter of credit
Letter of Credit [Member]
Operating Leased Assets [Line Items]
Operating Leased Assets [Line Items]
Tenant improvement allowance
Payments for (Proceeds from) Tenant Allowance
Letter of credit
Line of Credit Facility, Maximum Borrowing Capacity
Area exchanged (in square feet)
Area of Real Estate Property
Deferred rent and lease incentive liability
Deferred Rent And Lease Incentive Liability
This element represents both current and non current costs incurred by the lessor that are (a) costs to originate a lease incurred in transactions with independent third parties that (i) result directly from and are essential to acquire that lease and (ii) would not have been incurred had that leasing transaction not occurred and (b) certain costs directly related to specified activities performed by the lessor for that lease and includes the deferred charge for an incentive or inducement granted by a lessor to a lessee, in order to motivate the lessee to enter the lease agreement, which incentive or inducement is to be recognized as a reduction of rental revenue over the lease term.
Current portion of deferred rent and lease incentive liability (less than)
Accrued Rent And Lease Incentive Payable Current
" Carrying value as of the balance sheet date of obligations incurred through that date and payable for contractual rent under lease arrangements and an incentive or inducement contractually stipulated between parties to a lease whereby the lessor has committed to provide the entity (lessee) with a cash payment as inducement to enter the lease. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer)."
Rent expense, net of sublease payments
Operating Leases, Rent Expense, Net
Schedule of Future Minimum Lease Payments
Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block]
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Collaborative Arrangements and Non-collaborative Arrangement Transactions [Table]
Schedule of Collaborative Arrangements and Non-collaborative Arrangement Transactions [Table]
Type of Arrangement and Non-arrangement Transactions [Axis]
Type of Arrangement and Non-arrangement Transactions [Axis]
Arrangements and Non-arrangement Transactions [Domain]
Arrangements and Non-arrangement Transactions [Domain]
MIT
Exclusive Patent License Agreement With Massachusetts Institute Of Technology [Member]
Represents information pertaining to Exclusive patent license agreement with Massachusetts Institute of Technology.
"
Minimum
Minimum [Member]
Spark License Agreement
License Agreement Terms [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of sublicense income
Percentage Of Sublicense Income
Represents information pertaining to percentage of sublicense income.
Payment amount upon achievement of defined clinical milestones
Payment Amount Upon Achievement Of Defined Clinical Milestones
Represents information pertaining to payment amount upon achievement of defined clinical milestones.
Contractual payments defined in the Exclusive Patent License agreement
License And Option Agreement, Contractual Payments Made
License And Option Agreement, Contractual Payments Made
Payment relative to calculated premium paid by Spark for initial equity investment
License And Option Agreement, Payments Made Relative To Calculated Premium Paid For Initial Equity Investment
License And Option Agreement, Payments Made Relative To Calculated Premium Paid For Initial Equity Investment
Technology License Agreements
Technology License Agreements [Text Block]
The entire disclosure for technology license agreements.
Sanofi
Sanofi Collaboration Agreement [Member]
Represents information pertaining to collaboration agreement with Sanofi.
Aggregate payments under Sanofi Agreement
Aggregate Amount Of Upfront And Milestone Based Payments
Represents information pertaining to aggregate amount of upfront and milestone based payments.
Remaining revenue recognized
Deferred Revenue, Revenue Recognized
Property, Plant and Equipment [Abstract]
Property and Equipment
Property, Plant and Equipment Disclosure [Text Block]
Revenue Arrangements
Collaborative Arrangement Disclosure [Text Block]
Debt Disclosure [Abstract]
Line of Credit Facility [Table]
Line of Credit Facility [Table]
Term Loans
Term Loan [Member]
Represents information pertaining to term loan member.
Line of Credit Facility [Line Items]
Line of Credit Facility [Line Items]
Year ended December 31,
Long-term Debt, Fiscal Year Maturity [Abstract]
Remaining for 2017
Long-Term Debt, Maturities, Repayments Of Principal And Interest In Next Twelve Months
Long-Term Debt, Maturities, Repayments Of Principal And Interest In Next Twelve Months
2018
Long-Term Debt, Maturities, Repayments Of Principal And Interest In Year Two
Long-Term Debt, Maturities, Repayments Of Principal And Interest In Year Two
2019
Long-Term Debt, Maturities, Repayments Of Principal And Interest In Year Three
Long-Term Debt, Maturities, Repayments Of Principal And Interest In Year Three
Total minimum debt payments
Long-Term Debt, Maturities, Total Repayments Of Principal And Interest
Long-Term Debt, Maturities, Total Repayments Of Principal And Interest
Less: Amount representing interest
Debt Instrument Interest Portion
The interest portion of gross outstanding debt.
Less: Debt discount and deferred charges
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net
Less: Current portion of loans payable
Long-term Debt, Current Maturities
Loans payable, net of current portion
Long-term Debt, Excluding Current Maturities
Investments, Debt and Equity Securities [Abstract]
Available-for-Sale Marketable Securities
Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]
Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]
Plan Name [Axis]
Plan Name [Axis]
Plan Name [Domain]
Plan Name [Domain]
The 2008 Plan and the 2016 Plan
The 2008 Plan And The 2016 Plan [Member]
The 2008 Plan And The 2016 Plan [Member]
Award Type [Axis]
Award Type [Axis]
Equity Award [Domain]
Equity Award [Domain]
Employee
Stock Compensation Plan [Member]
Non‑Employee
Non Employee Stock Option [Member]
An arrangement whereby a non-employee is entitled to receive in the future, subject to vesting and other restrictions, a number of shares in the entity at a specified price, as defined in the agreement.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Beginning balance (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number
Granted (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross
Exercised (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period
Forfeited (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period
Ending balance (in shares)
Vested (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares
Vested and expected to vest (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number
Weighted-average exercise price
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Beginning balance (in dollars per share)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price
Granted (in dollars per share)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price
Exercised (in dollars per share)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price
Forfeited (in dollars per share)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price
Ending balance (in dollars per share)
Vested (in dollars per share)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Exercise Price
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Exercise Price
Vested and expected to vest (in dollars per share)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price
Weighted-average remaining contractual term
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term [Abstract]
n/a
Outstanding, term
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term
Vested, term
Share-based Compensation Arrangement By Share-based Payment Award, Options, Vested, Outstanding, Weighted Average Remaining Contractual Term
Share-based Compensation Arrangement By Share-based Payment Award, Options, Vested, Outstanding, Weighted Average Remaining Contractual Term
Vested and expected to vest, term
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term
Aggregate intrinsic value
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value [Abstract]
n/a
Outstanding
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value
Vested
Share-based Compensation Arrangement By Share-based Payment Award, Options, Vested, Outstanding, Intrinsic Value
Share-based Compensation Arrangement By Share-based Payment Award, Options, Vested, Outstanding, Intrinsic Value
Vested and expected to vest
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value
Compensation and Retirement Disclosure [Abstract]
401(k) Savings Plan
Pension and Other Postretirement Benefits Disclosure [Text Block]
Fair value of underlying common shares (in dollars per share)
Convertible Preferred Stock Warrants Fair Value Of Underlying Common Shares
The price per share of the fair value of the underlying common shares of convertible preferred stock warrants.
Other Research And Collaboration Agreements
Other Research And Collaboration Agreements [Member]
Represents information pertaining to other research and collaboration agreements.
Revenue recognized (less than in 2016)
Research and Development Arrangement, Contract to Perform for Others, Compensation Earned
Summary of Significant Accounting Policies
Significant Accounting Policies [Text Block]
3SBio License
License Agreement With Shenyang Sunshine Pharmaceutical Company Limited [Member]
Represents information pertaining to License agreement with Shenyang Sunshine Pharmaceutical co., ltd.
Period after approval to commercialize product
Period For Commercialization Of Product
Represents information pertaining to period for commercialization of product.
Aggregate amount of upfront and milestone-based payments
Aggregate Amount Of Upfront And Milestone Based Payments Paid
Aggregate Amount Of Upfront And Milestone Based Payments Paid
Additional liability for milestone payments expensed in 2016
Upfront And Milestone Based Payments, Additional Liability
Upfront And Milestone Based Payments, Additional Liability
Aggregate amount for future payments upon achievement of clinical and regulatory approval milestones for products containing SVP technology
Aggregate Amount For Future Payments Upon Achievement Of Clinical And Regulatory Approval Milestones For Products Containing Svp Technology
Represents information pertaining to aggregate amount for future payments upon achievement of clinical and regulatory approval milestones for product containing SVP technology.
Aggregate amount for future payments upon achievement of clinical and regulatory approval milestones for products without SVP technology
Aggregate Amount For Future Payments Upon Achievement Of Clinical And Regulatory Approval Milestones For Products Without Svp Technology
Represents information pertaining to aggregate amount for future payments upon achievement of clinical and regulatory approval milestones for product without SVP technology.
Period for prior written notice to terminate license
Period For Prior Written Notice To Terminate License
Represents information pertaining to period for prior written notice to terminate license.
Common Stock, shares authorized
Common Stock, Shares Authorized
Common Stock, par value (in dollars per share)
Common Stock, Par or Stated Value Per Share
Common Stock, shares issued
Common Stock, Shares, Issued
Common Stock, shares outstanding
Common Stock, Shares, Outstanding
Number of votes per share that common stockholders are entitled to
Votes Per Share of Common Stock
Votes Per Share of Common Stock
Dividends declared or paid on common stock
Dividends, Common Stock
Subsequent Events [Abstract]
Subsequent Events
Subsequent Events [Text Block]
Income Tax Disclosure [Abstract]
Income Tax Holiday [Table]
Income Tax Holiday [Table]
Legal Entity [Axis]
Legal Entity [Axis]
Entity [Domain]
Entity [Domain]
Russian subsidiary
Subsidiaries [Member]
Income Tax Authority [Axis]
Income Tax Authority [Axis]
Income Tax Authority [Domain]
Income Tax Authority [Domain]
Russia
Domestic Tax Authority [Member]
Income Tax Authority, Name [Axis]
Income Tax Authority, Name [Axis]
Income Tax Authority, Name [Domain]
Income Tax Authority, Name [Domain]
Russian Federal Tax Service
Russian Federal Tax Service [Member]
Russian Federal Tax Service [Member]
Income Tax Holiday [Line Items]
Income Tax Holiday [Line Items]
Term of tax holiday granted to Russian subsidiary
Income Tax Holiday, Term
Income Tax Holiday, Term
Commitments and Contingencies
Commitments and Contingencies Disclosure [Text Block]
Number of additional target therapy options
Number Of Additional Target Therapy Options
Number Of Additional Target Therapy Options
Fair value of initial purchase of common stock combined with the embedded future stock Acquisition Rights
Stock Issued During Period, Value, Purchase of Assets
Total non-contingent payments
License And Option Agreement, Total Non-Contingent Payments
License And Option Agreement, Total Non-Contingent Payments
Consideration allocated to combined unit of accounting for License and Supply Deliverable
Revenue Recognition, Multiple-deliverable Arrangements, Determination of Selling Price, Amount
Discount associated with Option Deliverable
License And Option Agreement, Discount Associated With Option Deliverable
License And Option Agreement, Discount Associated With Option Deliverable
Estimated initial term to recognize expected deliveries
Revenue Recognition, Multiple-Deliverable Arrangements, Allocation to Specific Unit of Accounting, Assumptions, Initial Estimated Performance Period
Revenue Recognition, Multiple-Deliverable Arrangements, Allocation to Specific Unit of Accounting, Assumptions, Initial Estimated Performance Period
Revenue recognized under agreement (less than in 2017)
Deferred revenue related to agreement
Deferred Revenue
Deferred revenue recorded as a current liability
Deferred revenue classified as a long term liability
Preferred stock, par value (in dollars per share)
Preferred Stock, Par or Stated Value Per Share
Preferred stock, shares authorized
Preferred Stock, Shares Authorized
Preferred stock, shares issued
Preferred Stock, Shares Issued
Preferred stock, shares outstanding
Preferred Stock, Shares Outstanding
Common stock, par value (in dollars per share)
Common stock, shares authorized
Common stock, shares issued
Common stock, shares outstanding
Schedule of Future Minimum Payments on the Term Loans
Schedule of Maturities of Long-term Debt [Table Text Block]
Year ended December 31,
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2017
Operating Leases, Future Minimum Payments Due, Next Twelve Months
2018
Operating Leases, Future Minimum Payments, Due in Two Years
2019
Operating Leases, Future Minimum Payments, Due in Three Years
2020
Operating Leases, Future Minimum Payments, Due in Four Years
Total minimum lease payments
Operating Leases, Future Minimum Payments Due
Restricted stock
Restricted Stock [Member]
Number of shares issued upon the early exercise of stock options
Number of shares issued
Stock Issued During Period, Shares, New Issues
Cumulative payments received
Proceeds from Issuance of Common Stock
Unrecognized compensation cost related to unvested restricted stock
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options
Earnings Per Share [Abstract]
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table]
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table]
Antidilutive Securities [Axis]
Antidilutive Securities [Axis]
Antidilutive Securities, Name [Domain]
Antidilutive Securities, Name [Domain]
Redeemable convertible preferred stock
Redeemable Convertible Preferred Stock [Member]
Stock options to purchase common stock
Employee Stock Option [Member]
Stock warrants to purchase common stock
Warrant [Member]
Redeemable convertible preferred stock warrants
Redeemable Convertible Preferred Stock Warrants [Member]
Redeemable Convertible Preferred Stock Warrants [Member]
Potential common shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount
Temporary Equity Disclosure [Abstract]
Authorized shares of Preferred Stock (in shares)
Temporary Equity, Shares Authorized
Preferred Stock, par value (in dollars per share)
Temporary Equity, Par or Stated Value Per Share
Temporary Equity, by Class of Stock [Table]
Temporary Equity, by Class of Stock [Table]
Class of Stock [Axis]
Class of Stock [Axis]
Class of Stock [Domain]
Class of Stock [Domain]
Series A Preferred
Series A Redeemable Convertible Preferred Stock [Member]
Represents information pertaining to series A redeemable convertible preferred stock.
Series B Preferred
Series B Redeemable Convertible Preferred Stock [Member]
Represents information pertaining to series B redeemable convertible preferred stock.
Series C Preferred
Series C Redeemable Convertible Preferred Stock [Member]
Represents information pertaining to series C redeemable convertible preferred stock.
Series D Preferred
Series D Redeemable Convertible Preferred Stock [Member]
Represents information pertaining to series D redeemable convertible preferred stock.
Series SRN Preferred
Series SRN Redeemable Convertible Preferred Stock [Member]
Represents information pertaining to series SRN redeemable convertible preferred stock.
Series E Preferred
Series E Redeemable Convertible Preferred Stock [Member]
Represents information pertaining to series E redeemable convertible preferred stock.
Debt Instrument [Axis]
Debt Instrument [Axis]
Debt Instrument, Name [Domain]
Debt Instrument, Name [Domain]
Convertible notes
Convertible Notes Payable [Member]
Stock Conversion Description [Axis]
Stock Conversion Description [Axis]
Conversion of Stock, Name [Domain]
Conversion of Stock, Name [Domain]
Preferred stock automatically converted into common stock upon the closing of the IPO
Preferred Stock Automatically Converted Into Common Stock Upon Closing Of Initial Public Offering [Member]
Preferred Stock Automatically Converted Into Common Stock Upon Closing Of Initial Public Offering [Member]
Preferred stock
Temporary Equity [Line Items]
Convertible preferred stock, shares issued
Temporary Equity, Shares Issued
Price per share (in dollars per share)
Shares Issued, Price Per Share
Total net proceeds from issuance of stock
Proceeds from Issuance of Redeemable Convertible Preferred Stock
Conversion price (in dollars per share)
Temporary Equity Conversion Price Per Share
Represents information pertaining to temporary equity conversion price per share.
Carrying value of Series SRN Preferred
Temporary Equity, Carrying Amount, Attributable to Parent
Difference recorded as additional paid in capital
Adjustments to Additional Paid in Capital, Increase in Carrying Amount of Redeemable Preferred Stock
Total gross proceeds from issuance of Series E Preferred
Proceeds From Issuance Of Redeemable Convertible Preferred Stock Gross
The gross cash inflow from issuance of callable preferred stock which is identified as being convertible to another type of financial security at the option of the issuer or the holder.
Issuance costs
Payments of Stock Issuance Costs
Warrants to purchase common stock, percentage of Series E Preferred shares issued
Class of Warrant or Right, Percentage Of Securities Called by Warrants or Rights
Class of Warrant or Right, Percentage Of Securities Called by Warrants or Rights
Convertible preferred stock automatically converted into common stock (in shares)
Conversion of Stock, Shares Converted
Summary of Available-for-Sale Marketable Securities
Schedule of Available-for-sale Securities Reconciliation [Table Text Block]
Schedule of Fair Values and Amortized Cost of Marketable Debt Securities by Contractual Maturity
Investments Classified by Contractual Maturity Date [Table Text Block]
Number of operating segments
Number of Operating Segments
New Accounting Pronouncements or Change in Accounting Principle [Table]
New Accounting Pronouncements or Change in Accounting Principle [Table]
Prospective Adoption of New Accounting Pronouncements [Axis]
Prospective Adoption of New Accounting Pronouncements [Axis]
Accounting Guidance [Domain]
Accounting Guidance [Domain]
ASU 2014-09
Accounting Standards Update 2014-09 [Member]
Adjustments for New Accounting Pronouncements [Axis]
Adjustments for New Accounting Pronouncements [Axis]
Type of Adoption [Domain]
Type of Adoption [Domain]
Accounting Standards Update 2016-09, Excess Tax Benefit Component
Accounting Standards Update 2016-09, Excess Tax Benefit Component [Member]
Accounting Standards Update 2016-09, Excess Tax Benefit Component [Member]
ASU 2016-18
Accounting Standards Update 2016-18 [Member]
Accounting Standards Update 2016-18 [Member]
Scenario [Axis]
Scenario [Axis]
Scenario, Unspecified [Domain]
Scenario, Unspecified [Domain]
Scenario, Forecast
Scenario, Forecast [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of revenue contracts that would require assessment under ASU 2014-09
Number Of Revenue Contracts
Number Of Revenue Contracts
Increase in net operating losses deferred tax assets
Deferred Tax Assets, Operating Loss Carryforwards
Corresponding increase in the valuation allowance
Operating Loss Carryforwards, Valuation Allowance
Cash and cash equivalents at beginning of period, presented upon implementation of ASU 2016-18
Cash, Cash Equivalents, Restricted Cash And Restricted Cash Equivalents
Cash, Cash Equivalents, Restricted Cash And Restricted Cash Equivalents
Accumulated Other Comprehensive Income (Loss) [Table]
Accumulated Other Comprehensive Income (Loss) [Table]
Equity Components [Axis]
Equity Components [Axis]
Equity Component [Domain]
Equity Component [Domain]
Foreign exchange translation adjustment
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Unrealized gains (losses) on available-for-sale securities
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Accumulated other comprehensive income (loss)
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI Attributable to Parent, Net of Tax
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance
Other comprehensive gain (loss) during the period
Other Comprehensive Income (Loss), Net of Tax
Ending balance
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Subsidiary or Equity Method Investee, Sale of Stock by Subsidiary or Equity Investee [Table]
Subsidiary or Equity Method Investee, Sale of Stock by Subsidiary or Equity Investee [Table]
Sale of Stock [Axis]
Sale of Stock [Axis]
Sale of Stock [Domain]
Sale of Stock [Domain]
IPO
IPO [Member]
Over-Allotment Option
Over-Allotment Option [Member]
Subsidiary, Sale of Stock [Line Items]
Subsidiary, Sale of Stock [Line Items]
Price to the public (in dollars per share)
Net proceeds
Proceeds from Issuance Initial Public Offering
Common stock issued for convertible preferred stock (in shares)
Convertible Preferred Stock, Shares Issued upon Conversion
Fair Value Disclosures [Abstract]
Fair Value Measurements, Recurring and Nonrecurring [Table]
Fair Value Measurements, Recurring and Nonrecurring [Table]
Measurement Frequency [Axis]
Measurement Frequency [Axis]
Fair Value, Measurement Frequency [Domain]
Fair Value, Measurement Frequency [Domain]
Recurring
Fair Value, Measurements, Recurring [Member]
Cash and Cash Equivalents [Axis]
Cash and Cash Equivalents [Axis]
Cash and Cash Equivalents [Domain]
Cash and Cash Equivalents [Domain]
Money market funds, included in cash equivalents
Money Market Funds [Member]
Tri-party repurchase agreements, included in cash equivalents
Repurchase Agreements [Member]
Major Types of Debt and Equity Securities [Axis]
Major Types of Debt and Equity Securities [Axis]
Major Types of Debt and Equity Securities [Domain]
Major Types of Debt and Equity Securities [Domain]
Corporate bonds, included in investments
Corporate Bond Securities [Member]
Fair Value, Hierarchy [Axis]
Fair Value, Hierarchy [Axis]
Fair Value Hierarchy [Domain]
Fair Value Hierarchy [Domain]
(level 1)
Fair Value, Inputs, Level 1 [Member]
(level 2)
Fair Value, Inputs, Level 2 [Member]
(level 3)
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Included in cash equivalents
Cash and Cash Equivalents, Fair Value Disclosure
Included in investments
Investments, Fair Value Disclosure
Statement of Cash Flows [Abstract]
Operating activities
Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract]
Net loss
Net Income (Loss) Attributable to Parent
Adjustments to reconcile net loss to net cash used in operating activities:
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]
Depreciation
Depreciation
Amortization of premiums and accretion of discounts on investments
Accretion (Amortization) of Discounts and Premiums, Investments
Stock‑based compensation expense
Allocated Share-based Compensation Expense
Non‑cash interest expense
Paid-in-Kind Interest
Change in fair value of redeemable convertible preferred stock warrant
Fair Value Adjustment of Warrants
Changes in operating assets and liabilities:
Increase (Decrease) in Operating Capital [Abstract]
Accounts receivable
Increase (Decrease) in Accounts Receivable
Prepaid expenses and other assets
Increase (Decrease) in Prepaid Expense and Other Assets
Restricted cash and other deposits
Increase (Decrease) in Restricted Cash for Operating Activities
Accounts payable
Increase (Decrease) in Accounts Payable
Deferred revenue
Increase (Decrease) in Deferred Revenue
Accrued expenses and other liabilities
Increase (Decrease) in Accrued Liabilities and Other Operating Liabilities
Net cash used in operating activities
Net Cash Provided by (Used in) Operating Activities
Investing activities
Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract]
Purchase of short term investments
Payments to Acquire Short-term Investments
Purchases of property and equipment
Payments to Acquire Property, Plant, and Equipment
Net cash used in investing activities
Net Cash Provided by (Used in) Investing Activities
Financing activities
Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract]
Principle payments on loan payable
Repayments of Long-term Debt
Deferred IPO costs paid
Exercise of stock options
Proceeds from Stock Options Exercised
Net cash provided by financing activities
Net Cash Provided by (Used in) Financing Activities
Effect of exchange rate changes on cash
Effect of Exchange Rate on Cash and Cash Equivalents, Continuing Operations
Net decrease in cash and cash equivalents
Cash and Cash Equivalents, Period Increase (Decrease)
Cash and cash equivalents at beginning of period
Cash and cash equivalents at end of period
Cash paid during the year for:
Supplemental Cash Flow Information [Abstract]
Interest
Interest Paid
Supplemental noncash investing and financing activities:
Noncash Investing and Financing Items [Abstract]
Purchase of property and equipment not yet paid
Capital Expenditures Incurred but Not yet Paid
Accrued dividends and accretion of preferred stock to redemption value
Temporary Equity, Accretion to Redemption Value
Unrealized gain on marketable securities
Marketable Securities, Unrealized Gain (Loss)
Statement of Stockholders' Equity [Abstract]
Statement [Table]
Statement [Table]
Common stock
Common Stock [Member]
Additional paid-In Capital
Additional Paid-in Capital [Member]
Stock option receivable
Receivables from Stockholder [Member]
Accumulated deficit
Retained Earnings [Member]
Accumulated other comprehensive loss
Statement [Line Items]
Statement [Line Items]
Increase (Decrease) in Stockholders' Equity
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)
Issuance of common stock under Employee Stock Purchase Plan (in shares)
Stock Issued During Period, Shares, Employee Stock Purchase Plans
Issuance of common stock under Employee Stock Purchase Plan
Stock Issued During Period, Value, Employee Stock Purchase Plan
Issuance of common stock upon exercise of options (in shares)
Issuance of common stock upon exercise of options
Stock Issued During Period, Value, Stock Options Exercised
Stock‑based compensation expense
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition
Currency translation adjustment
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax
Unrealized gains (losses) on securities
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax
Ending balance (in shares)
Bill and Melinda Gates Foundation
Bill And Melinda Gates Foundation Grant Agreement [Member]
Represents information pertaining to Bill and Melinda gates foundation grant agreement.
Aggregate amount of grant
Extended research term
Extended Research Term
Represents information pertaining to extended research term.
Revenue recognized (less than)
Skolkovo
Russia Vased Development Fund Of New Technologies Development And Commercialization Center Grant Agreement [Member]
Represents information pertaining to russi vased development fund of new technologies development and commercialization center grant agreement.
Percentage of estimated total cost of research plan
Percentage Of Estimated Cost Of Research Plan
Represents information pertaining to percentage of estimated cost of research plan.
Remaining percentage of estimated costs to be contributed by the Company
Remaining Percentage Contributed By The Entity
Represents information pertaining to remaining percentage contributed by the entity.
Period after completion of project when Company may be required to reimburse the funds received
Stock Incentive Plans
Disclosure of Compensation Related Costs, Share-based Payments [Text Block]
Numerator:
Net Income (Loss) Available to Common Stockholders, Basic [Abstract]
Net (loss)
Less: accretion on preferred stock
Temporary Equity, Accretion to Redemption Value, Adjustment
Net loss attributable to common stockholders
Net Income (Loss) Available to Common Stockholders, Basic
Denominator:
Weighted Average Number of Shares Outstanding, Diluted [Abstract]
Weighted‑average common shares outstanding—basic and diluted (in shares)
Weighted Average Number of Shares Outstanding, Basic and Diluted
Net loss per share attributable to common stockholders—basic and diluted (in dollars per share)
Earnings Per Share, Basic and Diluted
Preferred Stock
Temporary Equity Disclosure [Text Block]
The entire disclosure for temporary equity.
JDRF
Juvenile Diabetes Research Foundation Grant Agreement [Member]
Represents information pertaining to Juvenile Diabetes research foundation grant agreement.
Project [Axis]
Project [Axis]
Project [Domain]
Project [Domain]
First Contract
First Contract [Member]
First Contract [Member]
Second Contract
Second Contract [Member]
Second Contract [Member]
Number of contracts in effect
Number Of Contracts In Effect
Number Of Contracts In Effect
Schedule of Available-for-sale Securities [Table]
Schedule of Available-for-sale Securities [Table]
U.S. Treasury securities
US Treasury Securities [Member]
Corporate bonds
Schedule of Available-for-sale Securities [Line Items]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost
Available-for-sale Securities, Amortized Cost Basis
Gross Unrealized Gains
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax
Gross Unrealized Losses
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax
Estimated Fair Value
Available-for-sale Securities
Net Loss Per Share
Earnings Per Share [Text Block]
Schedule of Long-term Debt Instruments [Table]
Schedule of Long-term Debt Instruments [Table]
Long-term Debt, Type [Axis]
Long-term Debt, Type [Axis]
Long-term Debt, Type [Domain]
Long-term Debt, Type [Domain]
Loans payable
Loans Payable [Member]
Debt Instrument [Line Items]
Debt Instrument [Line Items]
Effective interest rate for the debt arrangement
Debt Instrument, Interest Rate, Effective Percentage
Common stock
Conversion of Series E Preferred
Convertible notes interest rate per annum
Debt Instrument, Interest Rate, Stated Percentage
Percentage of convertible notes for which warrants were issued to purchase common stock
Percentage of Convertible Notes for Which Warrants Issued to Purchase Common Stock
Represents the percentage of convertible notes for which warrants issued to purchase equivalent common stock shares.
Exercise price (in dollars per share)
Class of Warrant or Right, Exercise Price of Warrants or Rights
Warrants issued to convertible note holders (in shares)
Class of Warrant or Right, Number of Securities Called by Warrants or Rights
Term of warrants
Class Of Warrants Or Rights, Term
Period of time between issuance and maturity of warrant, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
Shares issued on conversion of outstanding convertible notes (in shares)
Debt Conversion, Converted Instrument, Shares Issued
Interest expense related to the convertible notes
Interest Expense, Debt
Corporate Bonds
Tri-party repurchase agreements collateralized by government securities (not less than) (as a percent)
Cash And Cash Equivalents Collateralized By Government Securities, Value Of Collateral, Percent Of Fair Value
Cash And Cash Equivalents Collateralized By Government Securities, Value Of Collateral, Percent Of Fair Value
Average maturity, term
Investments Maturity Period
Represents information pertaining to US treasury obligations in investments maturity period.
Statement of Comprehensive Income [Abstract]
Grant and collaboration revenue
Revenues
Operating expenses:
Cost of Revenue [Abstract]
Research and development
Research and Development Expense
General and administrative
General and Administrative Expense
Total operating expenses
Operating Expenses
Loss from operations
Operating Income (Loss)
Investment income
Investment Income, Net
Foreign currency transaction gain (loss), net
Foreign Currency Transaction Gain (Loss), before Tax
Interest expense
Interest Expense
Other expense, net
Other Nonoperating Income (Expense)
Net loss
Other comprehensive loss:
Other Comprehensive Income (Loss), Tax [Abstract]
Foreign currency translation adjustment
Unrealized gain (loss) on securities
Comprehensive loss
Comprehensive Income (Loss), Net of Tax, Attributable to Parent
Accretion of redeemable convertible preferred stock
Net loss per share attributable to common stockholders
Earnings Per Share, Basic and Diluted [Abstract]
Basic and diluted (in dollars per share)
Weighted average common shares outstanding
Basic and diluted (in shares)
Property, Plant and Equipment [Table]
Property, Plant and Equipment [Table]
Property, Plant and Equipment, Type [Axis]
Property, Plant and Equipment, Type [Axis]
Property, Plant and Equipment, Type [Domain]
Property, Plant and Equipment, Type [Domain]
Furniture
Furniture and Fixtures [Member]
Equipment
Equipment [Member]
Computer and office equipment
Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment [Line Items]
Estimated useful life
Property, Plant and Equipment, Useful Life
Related Party Transactions [Abstract]
Schedule of Related Party Transactions, by Related Party [Table]
Schedule of Related Party Transactions, by Related Party [Table]
Related Party [Axis]
Related Party [Axis]
Related Party [Domain]
Related Party [Domain]
Landlord
Landlord [Member]
Represents information pertaining to landlord member.
Founders
Founder [Member]
Represents information pertaining to founder member.
Related Party Transaction [Line Items]
Related Party Transaction [Line Items]
Issued (in shares)
Share price (in dollars per share)
Total proceeds
Proceeds from Issuance of Convertible Preferred Stock
Bridge loan
Bridge Loan
Expenses for consulting services (less than)
Related Party Transaction, Expenses from Transactions with Related Party
Components of Accumulated Other Comprehensive Income (Loss), Net of Tax
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]
Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table]
Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table]
Stock options and restricted common stock
Stock Options And Restricted Common Stock [Member]
Stock Options And Restricted Common Stock [Member]
Income Statement Location [Axis]
Income Statement Location [Axis]
Income Statement Location [Domain]
Income Statement Location [Domain]
Research and development
Research And Development [Member]
Represents the information pertaining to research and development expenses included in the income statement.
General and administrative
General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total
Vesting [Axis]
Vesting [Axis]
Vesting [Domain]
Vesting [Domain]
Tranche One
Share-based Compensation Award, Tranche One [Member]
Tranche Two
Share-based Compensation Award, Tranche Two [Member]
2008 Plan
Stock Incentive Plan2008 [Member]
Represents the information pertaining to the 2008 stock incentive plan, which provides for the granting of stock based awards to employees, directors, and consultants under terms and provisions established by the board of directors.
2016 Plan
Stock Incentive Plan2016 [Member]
Represents the information pertaining to the 2016 stock incentive plan, which provides for the granting of stock based awards to employees, directors, and consultants under terms and provisions established by the board of directors.
ESPP
Employee Stock Purchase Plan2016 [Member]
Represent information pertaining to the 2016 Employee Stock Purchase Plan.
Shares available for future stock incentive awards
Non-employee stock options
Number of shares authorized for grants
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant
Number of shares available for future grants
Common Stock, Capital Shares Reserved for Future Issuance
Exercise price of incentive stock options (as a percent)
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent
Combined voting power of participants (as a percent)
Share-based Compensation Arrangement By Share-based Payment Award, Voting Rights of Common Stock, Holding Percentage
Represents the percentage of voting rights of all classes of stock held by the employees.
Award vesting term
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period
Award expiration term
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period
Estimated forfeitures rate
Share-based Compensation Arrangement By Share-based Payment Award Forfeitures Rate
Represents the percentage of forfeitures rate of the stock options based on the historical trends.
Weighted average grant date fair value of stock options (in dollars per share)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value
Aggregate intrinsic value of stock options exercised (less than in 2016)
Unrecognized compensation expense related to unvested employee stock options
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options
Weighted average period for recognition
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition
Non-employee stock-based compensation expense (less than in 2016)
Adjustment of Warrants Granted for Services
Unrecognized compensation expense related to unvested non-employee stock options
Share-Based Goods And Non Employee Services Transaction, Compensation Not Yet Recognized, Stock Options
Share-Based Goods And Non Employee Services Transaction, Compensation Not Yet Recognized, Stock Options
Payables and Accruals [Abstract]
Payroll and employee related expenses
Employee-related Liabilities, Current
Legal
Accrued Legal Fees, Current
Accrued Legal Fees, Current
Current portion of deferred rent and lease incentive
Accrued patent fees
Accrued Patent Fees Current
Carrying value as of the balance sheet date of patent fees.
Accrued external research and development costs
Accrued Research And Development Costs Current
Carrying value as of the balance sheet date of research and development costs.
Accrued audit fees
Accrued Audit Fees, Current
Accrued Audit Fees, Current
Accrued grant refund
Accrued Grant Refund, Current
Accrued Grant Refund, Current
Accrued interest
Interest Payable, Current
Other
Other Accrued Liabilities, Current
Accrued expenses
Document and Entity Information
Document Type
Document Type
Amendment Flag
Amendment Flag
Document Period End Date
Document Period End Date
Document Fiscal Year Focus
Document Fiscal Year Focus
Document Fiscal Period Focus
Document Fiscal Period Focus
Entity Registrant Name
Entity Registrant Name
Entity Central Index Key
Entity Central Index Key
Current Fiscal Year End Date
Current Fiscal Year End Date
Entity Filer Category
Entity Filer Category
Entity Common Stock, Shares Outstanding
Entity Common Stock, Shares Outstanding
Accrued Expenses
Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block]
Schedule of Stock by Class [Table]
Schedule of Stock by Class [Table]
Exercise of common warrants
Exercise of outstanding common stock options
Class of Stock [Line Items]
Class of Stock [Line Items]
Total (in shares)
Schedule of Accrued Expenses
Schedule of Accrued Liabilities [Table Text Block]
Schedule of Authorized Shares of Common Stock for Future Issuance
Schedule of Stock by Class [Table Text Block]
Depreciation expense
NIH
National Institutes Of Health Grant Agreement [Member]
Represents information pertaining to national institutes of health grant agreement.
First Grant
First Grant [Member]
Represents information pertaining to first grant under NIH.
Second Grant
Second Grant [Member]
Represents information pertaining to second grant under NIH.
Number of grants
Number Of Grants
Represents information pertaining to number of grants.
Schedule of Property and Equipment
Property, Plant and Equipment [Table Text Block]
Term Loans
Convertible Debt
Convertible Debt [Member]
Debt Covenant Period [Axis]
Debt Covenant Period [Axis]
Debt Covenant Period [Axis]
Debt Covenant Period [Domain]
Debt Covenant Period [Domain]
[Domain] for Debt Covenant Period [Axis]
Prepaid prior to first anniversary
Term Loan Prepaid Prior To First Anniversary [Member]
Represents information pertaining to prepayment of term loan prior to first anniversary.
Prepaid prior to first anniversary but before second
Term Loan Prepaid After First Anniversary But Before Second Anniversary [Member]
Represents information pertaining to prepayment of term loan after first anniversary but prior to second anniversary.
Prepaid after second anniversary
Term Loan Prepaid After Second Anniversary [Member]
Represents information pertaining to prepayment of term loan after second anniversary.
Conversion of Series D Preferred
Number of lenders
Number Of Lenders
Represents the number of lenders.
Borrowing capacity
Borrowings on loan and security agreement
Proceeds from Lines of Credit
Outstanding principal balance under Term Loans
Long-term Line of Credit
Interest rate per annum
Line of Credit Facility, Interest Rate During Period
Number of monthly installments
Debt Instrument, Term
Prepayment fee (as a percent)
Early Extinguishment Of Debt, Prepayment Fee Percentage
Percentage of fee payable on early extinguishment of debt.
Final payment fee (as a percent)
Final Payment Fee Percentage
Percentage of final fee payment payable on aggregate principal amounts borrowed.
Final payment fee
Debt Instrument, Periodic Payment Terms, Balloon Payment to be Paid
Warrants issued for purchase of stock (in shares)
Expiration period of warrants
Initial grant date fair value of warrants
Warrants, Grant Date Fair Value
Represents the initial grant date fair value of the warrants.
Interest expense related to the Term Loan
Number of warrants exercised to purchase common stock (in shares)
Number Of Warrants Exercised To Purchase Common Stock
Number Of Warrants Exercised To Purchase Common Stock
Net shares of common stock issued (in shares)
Stock Issued During Period, Shares, Common Stock Issued Upon Exercise Of Warrants
Stock Issued During Period, Shares, Common Stock Issued Upon Exercise Of Warrants
Schedule of Cash and Cash Equivalents [Table]
Schedule of Cash and Cash Equivalents [Table]
Cash and Cash Equivalents [Line Items]
Cash and Cash Equivalents [Line Items]
Agreements collateralized by U.S. treasury securities (no less than) (as a percent)
Realized gains or losses on sale of investments
Realized Investment Gains (Losses)
Number of offering periods under the ESPP
Number Of Offering Periods
Number Of Offering Periods
Term of each offering period
Offering Period
Offering Period
Eligible compensation withheld for use (up to) (as a percent)
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate
Purchase price of shares (as a percent)
Common stock authorized and reserved for future issuance (in shares)
Number of shares of common stock outstanding (as a percent)
Employee Stock Purchase Plan Maximum Percentage Of Shares Reserved Based On Shares Outstanding
The maximum percentage increase in the shares reserved for future issuance each year based on the number of common stock outstanding at the last day of the year.
Stock-based compensation expense (less than in 2017)
Shares of common stock issued to employees under the ESPP (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period
Debt
Debt Disclosure [Text Block]
Summary of Assets Measured at Fair Value on a Recurring Basis
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]
Principles of Consolidation
Consolidation, Policy [Policy Text Block]
Foreign Currency
Foreign Currency Transactions and Translations Policy [Policy Text Block]
Use of Estimates
Use of Estimates, Policy [Policy Text Block]
Segment Information
Segment Reporting, Policy [Policy Text Block]
Reverse stock split and Preferred stock
Stockholders' Equity, Policy [Policy Text Block]
Cash Equivalents and Short Term Investments
Cash Equivalents And Short Term Investments [Policy Text Block]
Disclosure of accounting policy for cash equivalents and short term investments.
Concentrations of Credit Risk and Off-Balance Sheet Risk
Concentration Risk, Credit Risk, Policy [Policy Text Block]
Fair Value of Financial Instruments
Fair Value of Financial Instruments, Policy [Policy Text Block]
Property and Equipment
Property, Plant and Equipment, Policy [Policy Text Block]
Impairment of Long-Lived Assets
Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]
Debt Issuance Costs
Debt, Policy [Policy Text Block]
Accumulated Other Comprehensive Income (Loss) and Comprehensive Loss
Comprehensive Income, Policy [Policy Text Block]
Revenue Recognition
Revenue Recognition, Policy [Policy Text Block]
Collaboration Revenue
Collaborative Arrangement, Accounting Policy [Policy Text Block]
Grant Agreements
Revenue Recognition Grant Revenue [Policy Text Block]
Disclosure of accounting policy for revenue recognition for revenue from grants.
Research and Development Costs
Research and Development Expense, Policy [Policy Text Block]
Clinical Trial Costs
Clinical Trial Costs [Policy Text Block]
Disclosure of accounting policy for clinical trial costs.
Income Taxes
Income Tax, Policy [Policy Text Block]
Warrants
Warrants [Policy Text Block]
Disclosure of accounting policy for warrants.
Stock-Based Compensation
Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block]
Net Loss Per Share
Earnings Per Share, Policy [Policy Text Block]
Deferred Rent
Deferred Rent [Policy Text Block]
Disclosure of accounting policy for deferred rent.
Contingent Liabilities
Contingent Liability Reserve Estimate, Policy [Policy Text Block]
Recent Accounting Pronouncements
New Accounting Pronouncements, Policy [Policy Text Block]
Schedule of Share-based Goods and Nonemployee Services Transaction [Table]
Schedule of Share-based Goods and Nonemployee Services Transaction [Table]
Share-based Goods and Nonemployee Services Transaction [Line Items]
Share-based Goods and Nonemployee Services Transaction [Line Items]
Risk‑free interest rate
Share-based Goods and Nonemployee Services Transaction, Valuation Method, Risk Free Interest Rate
Expected dividend yield (as a percent)
Share-based Goods and Nonemployee Services Transaction, Valuation Method, Expected Dividend Rate
Expected life
Share-based Goods and Nonemployee Services Transaction, Valuation Method, Expected Term
Expected volatility (as a percent)
Share-based Goods and Nonemployee Services Transaction, Valuation Method, Expected Volatility Rate
Computation of Basic and Diluted Net Loss Per Share
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]
Schedule of Potential Common Shares Issuable Upon Conversion of Warrants
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]
Related-Party Transactions
Related Party Transactions Disclosure [Text Block]
Employee stock option grants
The ESPP
Risk-free interest rate
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate
Expected dividend yield (as a percent)
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate
Expected life
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term
Expected volatility (as a percent)
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate
Weighted-average fair value of common stock (in dollars per share)
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Fair Value
Weighed-average fair value relating to the share-based payment award.
Concentration Risk [Table]
Concentration Risk [Table]
Geographical [Axis]
Geographical [Axis]
Geographical [Domain]
Geographical [Domain]
Russian subsidiary
RUSSIAN FEDERATION
Currency [Axis]
Currency [Axis]
All Currencies [Domain]
All Currencies [Domain]
U.S. dollars
United States of America, Dollars
Concentration Risk [Line Items]
Concentration Risk [Line Items]
Cash maintained in Russian bank accounts
Cash
Laboratory equipment
Laboratory Equipment [Member]
Represents information pertaining to laboratory equipment.
Computer equipment and software
Computer Equipment [Member]
Leasehold improvements
Leasehold Improvements [Member]
Furniture and fixtures
Office equipment
Total property and equipment
Property, Plant and Equipment, Gross
Less accumulated depreciation
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment
Property and equipment, net
Defined Contribution Plan [Table]
Defined Contribution Plan [Table]
Defined Contribution Plan Name [Axis]
Defined Contribution Plan Name [Axis]
Defined Contribution Plan Name [Domain]
Defined Contribution Plan Name [Domain]
401(k) Plan
401(k) Plan [Member]
401(k) Plan [Member]
Defined Contribution Plan Type [Axis]
Defined Contribution Plan Type [Axis]
Defined Contribution Plan Type [Domain]
Defined Contribution Plan Type [Domain]
Defined-contribution savings plan
Other Postretirement Benefit Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan Disclosure [Line Items]
Vesting period
Defined Contribution Plan Employers Matching Contribution Vesting Period
Period which an employee's right to exercise a plan is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
Employer contribution made
Defined Contribution Plan, Cost Recognized
Income Taxes
Income Tax Disclosure [Text Block]
Subsequent Event [Table]
Subsequent Event [Table]
Subsequent Event Type [Axis]
Subsequent Event Type [Axis]
Subsequent Event Type [Domain]
Subsequent Event Type [Domain]
Subsequent Event
Subsequent Event [Member]
License Agreement with NIH
Subsequent Event [Line Items]
Subsequent Event [Line Items]
Upfront payment for rights under the License Agreement
Initial License Fee Paid
Initial License Fee Paid
Aggregate payments upon achievement of specified benchmarks
Period after date of notice in writing when NIH may terminate License Agreement
Period After Written Notice Of Default When License Agreement May Be Terminated
Period After Written Notice Of Default When License Agreement May Be Terminated
Period for written notice to terminate License Agreement
Accumulated deficit
Russian subsidiary
Unrestricted cash
Unrestricted Cash [Member]
Unrestricted Cash [Member]
Unrestricted cash held by subsidiary
MEE
License Agreement With Massachusetts Eye And Ear Infirmary And Schepens Eye Research Institute Inc. [Member]
Represents information pertaining to License agreement with Massachusetts Eye and Ear Infirmary and The Schepens Eye Research Institute, Inc.
Minimum number of products for each target sequence
Number Of Products Marketed And Sold
Represents the number of products the Company has agreed to market and sell for each target sequence for which the Company exercised its option as soon as reasonably practicable.
Payment under development milestone method
Development Milestone Method, Amount Paid
The amount of consideration paid during the period for the development milestone or milestones.
Payment under sales milestone method
Sales Milestone Method, Amount Paid
The amount of consideration paid during the period for the sales milestone or milestones.
License fees due under agreement
Schedule of Weighted Average Assumptions Used for Stock Option Grants
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
Summary of Activity Under the 2008 Plan and the 2016 Plan
Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]
Schedule of Assumptions Used to Estimate the Fair Value of Purchase Rights Granted Under the ESPP
Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]
Schedule of Stock-Based Compensation Expense Related to Stock Options and Restricted Common Stock
Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block]
Fair Value
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
Less than one year
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value
Amortized Cost
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]
Less than one year
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Amortized Cost Basis
Number of positions in an unrealized loss position for less than 12 months
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year
Number of investment positions
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions
Other-than-temporary impairments
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities
Upfront payment for initial indication
Initial Payment For First Indication
Represents information pertaining to initial payment for first indication.
Additional payment for initial indication
Additional Payment For Preclinical Research For Each Indication
Represents information pertaining to additional payment for preclinical research for each indication.
Additional payments received upon exercise of option
Proceeds From Counterparty Exercise Of Option For Additional Indications
Proceeds From Counterparty Exercise Of Option For Additional Indications
Additional payment upon attaining first milestone for celiac disease indication
Initial period to complete research obligations
Initial Period To Complete Research Obligations
Initial Period To Complete Research Obligations
Revenue recognized
Fair Value Measurements
Fair Value Disclosures [Text Block]
Nature of the Business and Basis of Presentation
Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]
First Acquisition Right
First Acquisition Right [Member]
First Acquisition Right [Member]
Second Acquisition Right
Second Acquisition Right [Member]
Second Acquisition Right [Member]
Upfront cash payment
License And Option Agreement, Upfront Cash Payment
License And Option Agreement, Upfront Cash Payment
Aggregate additional payments due within twelve months
License And Option Agreement, Aggregate Additional Payments Due Within Twelve Months Of Contract Date
License And Option Agreement, Aggregate Additional Payments Due Within Twelve Months Of Contract Date
Number of additional targets
License And Option Agreement, Number Of Additional Targets For Which Other Party May Exercise Options For Additional Licenses
License And Option Agreement, Number Of Additional Targets For Which Other Party May Exercise Options For Additional Licenses
Variable fee the Company is eligible to receive for each additional target option elected
License And Option Agreement, Variable Fee To Be Received For Each Additional Target Option Elected
License And Option Agreement, Variable Fee To Be Received For Each Additional Target Option Elected
Election period to exercise additional targets
License And Option Agreement, Period For Other Party To Exercise Options For Additional Licenses
License And Option Agreement, Period For Other Party To Exercise Options For Additional Licenses
Additional development and regulatory milestone payments
License And Option Agreement, Additional Development And Regulatory Milestone Payments That May Be Received
License And Option Agreement, Additional Development And Regulatory Milestone Payments That May Be Received
Commercialization milestone payments
License And Option Agreement, Commercialization Milestone Payments That May Be Received
License And Option Agreement, Commercialization Milestone Payments That May Be Received
Period after first commercial sale when the Company is eligible to receive royalties
Eligible Period To Receive Royalties
Eligible Period To Receive Royalties
Period for prior written notice to terminate license
Number of shares issued
Stock Issued During Period, Shares, Purchase of Assets
Gross proceeds
Premium of average daily VWAP (as a percent)
Premium Of Average Daily Volume Weighted Average Price Of Common Stock, Percent
Premium Of Average Daily Volume Weighted Average Price Of Common Stock, Percent
Consecutive calendar days leading up to and ending on the day prior to the Contract Date
Consecutive Calendar Days Leading Up To Contract Date
Consecutive Calendar Days Leading Up To Contract Date
Aggregate price of shares Spark will have the right to purchase
Stock Purchase Agreement, Authorized Amount Of Stock To Sell
Stock Purchase Agreement, Authorized Amount Of Stock To Sell
Number of shares authorized to be issued pursuant to the Stock Purchase Agreement
Stock Purchase Program, Number Of Shares Authorized To Be Sold
Stock Purchase Program, Number Of Shares Authorized To Be Sold
Contractual payments made for MIT sub-license provided to Spark
Payment relative to calculated premium paid by Spark for initial equity investment