The aggregate principal amount of debt outstanding consisted of the following (in thousands):

	September 30,			December 31,
	2020			2019
Current portion of debt	$	7,500		$	5,625
Less: unamortized debt discount		(39	)		(49	)
Current portion of debt, net of debt discount	$	7,461		$	5,576
Long-term debt, net of current portion	$	3,750		$	9,375
Less: unamortized debt discount		(20	)		(82	)
Long-term debt, net of current portion	$	3,730		$	9,293

The Company entered into, and subsequently amended, a term loan facility with Pacific Western Bank, Inc. (“PWB”), and received $15.0 million debt proceeds. The loans bear interest at the greater of (i) 6.25% and (ii) the prime rate plus an applicable margin of 2.0%. The interest rate was 6.25% at September 30, 2020. In an event of default, as defined in the agreement, the interest rate applicable to borrowings would be increased by 5.0%. The Company made interest-only payments through March 31, 2020. Beginning in April 2020, the Company is obligated to make equal monthly principal payments of $625,000 through March 31, 2022 when the notes mature. The loan agreement allows for prepayment of the outstanding principal at any time, subject to a prepayment charge that is dependent on the prepayment date.

The debt agreement contained provisions whereby the Company was obligated to pay a success fee of $1.1 million upon the achievement of certain liquidity events. Upon consummation of the Merger, the Company success fee payment became due and was paid in its entirety in June 2020.

The 2018 Credit Facility contains a negative pledge on the Company’s intellectual property and also contains customary indemnification obligations and customary events of default, including, among other things, (i) non‑payment, (ii) breach of warranty, (iii) non‑performance of covenants and obligations, (iv) default on other indebtedness, (v) judgments, (iv) change of control, (vii) bankruptcy and insolvency, (viii) impairment of security, (ix) key permit events, (x) key person event, (xi) regulatory matters, (xii) and key contracts. In addition, the Company must maintain a minimum cash balance of $6.0 million beginning in April 2020. In the event of default under the 2018 Credit Facility, the Company would be required to pay interest on principal and all other due and unpaid obligations at the current rate in effect plus 5%.

The borrowings are collateralized by substantially all of the Company’s assets, excluding intellectual property, and contains affirmative and negative covenants including restrictions on the Company’s ability to incur additional indebtedness, pay dividends, encumber its property, or engage in certain fundamental business transactions, such as mergers or acquisitions of other businesses. The Company must maintain a minimum cash balance of $6.0 million beginning in April 2020. The Company was in compliance with its covenants as of September 30, 2020.

The Company recognized interest expense of $0.2 million and $0.3 million during the three months ended September 30, 2020 and 2019 and $0.7 million and $0.9 million during the nine months ended September 30, 2020 and 2019, respectively.

As of September 30, 2020, the aggregate minimum future principal payments due in connection with the 2018 Loan Agreement, as amended, are as follows (in thousands):

Year Ending December 31,
2020	$	1,875
2021		7,500
2022		1,875
	$	11,250