Debt	9 Months Ended
Sep. 30, 2019
Debt Disclosure [Abstract]
Debt	Debt On September 2, 2016, the Company entered into a loan and security agreement (as amended from time to time, the “Loan Agreement”) with OCM Strategic Credit SIGTEC Holdings, LLC (“Lender”), pursuant to which the Company received $80.0 million (less fees and other items) on November 16, 2016 having satisfied certain pre-conditions. Such $80.0 million had been placed in an escrow account on September 30, 2016 (the “Escrow Funding Date”). Prior to the Escrow Release Date (November 16, 2016), the Company did not have access to, or any ownership interest in, the escrow account. Until the Escrow Release Date occurred, the Company did not have an obligation to make any payments under the Loan Agreement, no security was granted under the Loan Agreement and no affirmative or negative covenants or events of default were effective under the Loan Agreement. Amounts were held in the escrow account until the satisfaction of certain conditions including the closing of the Rights Offering (see Note 7) on November 16, 2016. As part of the satisfaction of the PharmAthene claim, funds were released from the escrow account (the date on which such transfer occurred, the “Escrow Release Date”). The Loan Agreement provides for a first-priority senior secured term loan facility in the aggregate principal amount of $80.0 million (the “Term Loan”), of which (i) $25.0 million was placed in a reserve account (the “Reserve Account”) only to be utilized to pay interest on the Term Loan as it becomes due; (ii) an additional $5.0 million was also placed in the Reserve Account and up to the full amount of such $5.0 million was eligible to be withdrawn after June 30, 2018 upon the satisfaction of certain conditions, provided that any of such amount was required to fund any interest to the extent any interest in excess of the aforementioned $25.0 million was due and owing and any of such $5.0 million remained in the Reserve Account; and (iii) $50.0 million (net of fees and expenses then due and owing to the Lender) was paid as part of the final payment to satisfy a litigation claim. Interest on the Term Loan is at a per annum rate equal to the Adjusted LIBOR rate plus 11.5%, subject to adjustments as set forth in the Loan Agreement. At September 30, 2019, the effective interest rate on the Term Loan, which includes interest payments and accretion of unamortized costs and fees, was 19.2%. The Company incurred approximately $4.0 million of interest expense during the three months ended September 30, 2019, of which $1.1 million accreted to the Term Loan balance. On July 12, 2018, upon confirmation that there had been no events of default, $5 million was withdrawn by the Company from the Reserve Account and was placed in the Company's cash operating account. On October 31, 2018, the Loan Agreement was amended to expand the definition of permitted dispositions to include a sale of the PRV. In connection with the amendment, net cash proceeds from the sale of the PRV ($78.3 million) were placed in a restricted cash account; such restricted account is to be used only for interest, fees and principal payments (other than those in connection with an event of default) related to the Term Loan. The cash and cash equivalents balance in the restricted account was increased to $100.5 million as of July 24, 2019, in connection with an amendment to the Term Loan that allows the Company to diversify the financial institutions at which its remaining unrestricted cash and cash equivalents can be held. The balance in the restricted account represents an approximation of total payments that would be required pursuant to the Term Loan if it were to remain outstanding until its maturity. The Term Loan matures on the earliest to occur of (i) the four-year anniversary of the Escrow Release Date, which will be November 16, 2020, and (ii) the acceleration of certain obligations pursuant to the Loan Agreement. At maturity, $80.0 million of principal will be repaid, and an additional $4.0 million will be paid (see below). Prior to maturity, there are no scheduled principal payments. Through the three and one-half year anniversary of the Escrow Release Date, which will be May 16, 2020, any prepayment of the Term Loan is subject to a make-whole provision in which interest payments related to the prepaid amount are due (subject to a discount of treasury rate plus 0.50%). In connection with the Term Loan, the Company has granted the Lender a lien on and security interest in all of the Company’s right, title and interest in substantially all of the Company’s tangible and intangible assets, including all intellectual property. The Loan Agreement contains customary representations and warranties and customary affirmative and negative covenants. These covenants, among other things, require a minimum unrestricted cash balance throughout the term of the Term Loan and the achievement of regulatory milestones by certain dates, and contain certain limitations on the ability of the Company to incur unreimbursed research and development expenditures over a certain threshold, make capital expenditures over a certain threshold, incur indebtedness, dispose of assets outside of the ordinary course of business, make cash distributions and enter into certain merger or consolidation transactions. The minimum unrestricted cash requirement was $5.0 million until August 27, 2018 (45 days after FDA approval of oral TPOXX®), at which point the minimum unrestricted cash requirement became $20.0 million. The Loan Agreement includes customary events of default, including, among others: (i) non-payment of amounts due thereunder, (ii) the material inaccuracy of representations or warranties made thereunder, (iii) non-compliance with covenants thereunder, (iv) non-payment of amounts due under, or the acceleration of, other material indebtedness of the Company and (v) bankruptcy or insolvency events. Upon the occurrence and during the continuance of an event of default under the Loan Agreement, the interest rate may increase by 2.00% per annum above the rate of interest otherwise in effect, and the Lenders would be entitled to accelerate the maturity of the Company’s outstanding obligations thereunder. As of September 30, 2019, the Company was in compliance with the Loan Agreement covenants. In connection with the Loan Agreement, the Company incurred $8.2 million of costs (including interest on amounts held in the escrow account between September 30, 2016 and November 15, 2016). Furthermore, an additional $4.0 million will become payable when principal of the Term Loan is repaid. As part of the Company's entry into the Loan Agreement, the Company issued the Warrant (see Note 7) with a fair market value of $5.8 million. The fair value of the Warrant, as well as costs related to the Term Loan issuance, were recorded as deductions to the Term Loan balance on the Balance Sheet. These amounts are being amortized on a straight-line basis over the life of the related Term Loan. The Company compared the amortization under the effective interest method with the straight-line basis and determined the results were not materially different. The $4.0 million that will be paid when principal is repaid is being accreted to the Term Loan balance.

Debt

On September 2, 2016, the Company entered into a loan and security agreement (as amended from time to time, the “Loan Agreement”) with OCM Strategic Credit SIGTEC Holdings, LLC (“Lender”), pursuant to which the Company received $80.0 million (less fees and other items) on November 16, 2016 having satisfied certain pre-conditions. Such $80.0 million had been placed in an escrow account on September 30, 2016 (the “Escrow Funding Date”). Prior to the Escrow Release Date (November 16, 2016), the Company did not have access to, or any ownership interest in, the escrow account. Until the Escrow Release Date occurred, the Company did not have an obligation to make any payments under the Loan Agreement, no security was granted under the Loan Agreement and no affirmative or negative covenants or events of default were effective under the Loan Agreement. Amounts were held in the escrow account until the satisfaction of certain conditions including the closing of the Rights Offering (see Note 7) on November 16, 2016. As part of the satisfaction of the PharmAthene claim, funds were released from the escrow account (the date on which such transfer occurred, the “Escrow Release Date”).

The Loan Agreement provides for a first-priority senior secured term loan facility in the aggregate principal amount of $80.0 million (the “Term Loan”), of which (i) $25.0 million was placed in a reserve account (the “Reserve Account”) only to be utilized to pay interest on the Term Loan as it becomes due; (ii) an additional $5.0 million was also placed in the Reserve Account and up to the full amount of such $5.0 million was eligible to be withdrawn after June 30, 2018 upon the satisfaction of certain conditions, provided that any of such amount was required to fund any interest to the extent any interest in excess of the aforementioned $25.0 million was due and owing and any of such $5.0 million remained in the Reserve Account; and (iii) $50.0 million (net of fees and expenses then due and owing to the Lender) was paid as part of the final payment to satisfy a litigation claim. Interest on the Term Loan is at a per annum rate equal to the Adjusted LIBOR rate plus 11.5%, subject to adjustments as set forth in the Loan Agreement. At September 30, 2019, the effective interest rate on the Term Loan, which includes interest payments and accretion of unamortized costs and fees, was 19.2%. The Company incurred approximately $4.0 million of interest expense during the three months ended September 30, 2019, of which $1.1 million accreted to the Term Loan balance. On July 12, 2018, upon confirmation that there had been no events of default, $5 million was withdrawn by the Company from the Reserve Account and was placed in the Company's cash operating account. On October 31, 2018, the Loan Agreement was amended to expand the definition of permitted dispositions to include a sale of the PRV. In connection with the amendment, net cash proceeds from the sale of the PRV ($78.3 million) were placed in a restricted cash account; such restricted account is to be used only for interest, fees and principal payments (other than those in connection with an event of default) related to the Term Loan. The cash and cash equivalents balance in the restricted account was increased to $100.5 million as of July 24, 2019, in connection with an amendment to the Term Loan that allows the Company to diversify the financial institutions at which its remaining unrestricted cash and cash equivalents can be held. The balance in the restricted account represents an approximation of total payments that would be required pursuant to the Term Loan if it were to remain outstanding until its maturity.

The Term Loan matures on the earliest to occur of (i) the four-year anniversary of the Escrow Release Date, which will be November 16, 2020, and (ii) the acceleration of certain obligations pursuant to the Loan Agreement. At maturity, $80.0 million of principal will be repaid, and an additional $4.0 million will be paid (see below). Prior to maturity, there are no scheduled principal payments.

Through the three and one-half year anniversary of the Escrow Release Date, which will be May 16, 2020, any prepayment of the Term Loan is subject to a make-whole provision in which interest payments related to the prepaid amount are due (subject to a discount of treasury rate plus 0.50%).

In connection with the Term Loan, the Company has granted the Lender a lien on and security interest in all of the Company’s right, title and interest in substantially all of the Company’s tangible and intangible assets, including all intellectual property.

The Loan Agreement contains customary representations and warranties and customary affirmative and negative covenants. These covenants, among other things, require a minimum unrestricted cash balance throughout the term of the Term Loan and the achievement of regulatory milestones by certain dates, and contain certain limitations on the ability of the Company to incur unreimbursed research and development expenditures over a certain threshold, make capital expenditures over a certain threshold, incur indebtedness, dispose of assets outside of the ordinary course of business, make cash distributions and enter into certain merger or consolidation transactions. The minimum unrestricted cash requirement was $5.0 million until August 27, 2018 (45 days after FDA approval of oral TPOXX®), at which point the minimum unrestricted cash requirement became $20.0 million.

The Loan Agreement includes customary events of default, including, among others: (i) non-payment of amounts due thereunder, (ii) the material inaccuracy of representations or warranties made thereunder, (iii) non-compliance with covenants thereunder, (iv) non-payment of amounts due under, or the acceleration of, other material indebtedness of the Company and (v) bankruptcy or insolvency events. Upon the occurrence and during the continuance of an event of default under the Loan Agreement, the interest rate may increase by 2.00% per annum above the rate of interest otherwise in effect, and the Lenders would be entitled to accelerate the maturity of the Company’s outstanding obligations thereunder.

As of September 30, 2019, the Company was in compliance with the Loan Agreement covenants.

In connection with the Loan Agreement, the Company incurred $8.2 million of costs (including interest on amounts held in the escrow account between September 30, 2016 and November 15, 2016). Furthermore, an additional $4.0 million will become payable when principal of the Term Loan is repaid. As part of the Company's entry into the Loan Agreement, the Company issued the Warrant (see Note 7) with a fair market value of $5.8 million. The fair value of the Warrant, as well as costs related to the Term Loan issuance, were recorded as deductions to the Term Loan balance on the Balance Sheet. These amounts are being amortized on a straight-line basis over the life of the related Term Loan. The Company compared the amortization under the effective interest method with the straight-line basis and determined the results were not materially different. The $4.0 million that will be paid when principal is repaid is being accreted to the Term Loan balance.