9.Debt

We have a Credit and Security Agreement (Credit Agreement) with MidCap Financial Trust (MidCap) entered on September 27, 2019 (Closing Date) and amended on March 29, 2021 (First Amendment) and February 11, 2022 (Second Amendment). The Credit Agreement provides for a $60.0 million term loan credit facility. At the Closing Date, $10.0 million was funded (Tranche 1). In May 2020, an additional $10.0 million was funded (Tranche 2).

In March 2021, we entered into the First Amendment to the Credit Agreement to extend the period through which Tranche 3 will be available to us through March 31, 2022 at our option, subject to the satisfaction of certain conditions set forth in the Credit Agreement. In February 2022, we entered into the Second Amendment to our Credit Agreement which, among other things, amended the applicable funding conditions, applicable commitments and certain other terms relating to available credit facilities (Tranches 3 and 4), added additional term loan credit facility (Tranche 5), and revised certain terms related to the financial covenants. Following the Second Amendment, the Credit Agreement gives us the ability to access the following available credit facilities: (i) on the closing date of the Second Amendment, $10.0 million term loan facility (Tranche 3), (ii) at our option, an additional $10.0 million aggregate principal amount of term loan facility available on the Second Amendment effective date through March 31, 2023 (Tranche 4), which is subject to satisfaction of certain conditions if Tranche 4 is drawn on or after August 31, 2022, and (iii) at our option and

upon the satisfaction of certain conditions contained in the Credit Agreement, as amended, an additional $20.0 million aggregate principal amount of term loan available through March 31, 2023 (Tranche 5). At the Second Amendment effective date, $10.0 million was funded (Tranche 3).

As of March 31, 2022, the outstanding principal balance of the loan was $30.0 million. To date, the facility gives us the ability to access an additional $30.0 million at our option, subject to the achievement of certain customary conditions as discussed above.

The outstanding principal balance of the loan bears interest at an annual rate of one-month LIBOR (or a comparable applicable index rate determined pursuant to the Credit Agreement if the LIBOR is no longer available) plus 5.65%, subject to a LIBOR floor of 1.50% and is payable monthly in arrears. Commencing on October 1, 2019, the Credit Agreement provides that we initially make interest-only payments for 24 months followed by 36 months of amortization payments. The interest-only period can be extended to 36 months (first interest-only extension) and again to 48 months (second interest-only extension) upon the satisfaction of certain conditions set forth in the Credit Agreement. In June 2021, we satisfied the first interest-only extension conditions under the Credit Agreement which effectively extended the interest-only period to 36 months or through October 1, 2022. All unpaid principal and accrued interest are due and payable no later than September 1, 2024. A final payment fee of 2.5% of principal is due on the final payment of the term loan.

We may make voluntary prepayments, in whole or in part, subject to certain prepayment premiums and additional interest payments. The Credit Agreement also contains certain provisions, such as event of default and change in control provisions, which, if triggered, would require us to make mandatory prepayments on the term loan, which are subject to certain prepayment premiums and additional interest payments.

The obligations under the Credit Agreement are secured by a perfected security interest in all of our assets except for intellectual property and certain other customary excluded property pursuant to the terms of the Credit Agreement.

As of March 31, 2022 and December 31, 2021, the outstanding balance of the loan, net of unamortized debt discount, was $29.8 million and $19.9 million, respectively. As of March 31, 2022, we deemed that it is probable that we will satisfy the second interest-only criteria. Accordingly, we classified our outstanding loan as a long-term liability in the accompanying condensed balance sheet. Debt issuance costs are recorded as a direct deduction from the term loan on the condensed balance sheet with the resultant discount being amortized ratably as interest expense over the term of the loan, using the effective interest method. As of March 31, 2022 and December 31, 2021, the unamortized issuance costs and debt discounts amounted to $0.2 million and $0.1 million, respectively.

For the three months ended March 31, 2022 and 2021, interest expense, including amortization of the debt discount and accretion of the final fees related to the Credit Agreement was $0.5 million and $0.4 million, respectively. Accrued interest of $0.6 million was included within other accrued liabilities in the condensed balance sheet as of March 31, 2022.

The following table presents the future minimum principal payments of the outstanding loan as of March 31, 2022 under the current interest-only period as discussed above (in thousands):

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The Credit Agreement contains certain covenants which, among others, require us to deliver financial reports at designated times of the year and maintain minimum trailing net revenues and cash, cash equivalents and short-term investments balance. As of March 31, 2022, we were not in violation of any covenants.