Debt	3 Months Ended
Mar. 31, 2019
Debt
Debt	7. Debt Unsecured Revolving Credit Facility -- Credit Agreement In June 2018, we entered into a credit agreement (the Credit Agreement) with Wells Fargo Bank, National Association (Wells Fargo), as administrative agent and a swingline lender, and various other lender parties, providing for (1) an unsecured revolving credit facility of up to $1.0 billion; and (2) a second unsecured revolving credit facility of up to $500.0 million (which facilities may, at our request, be increased by up to $300 million in the aggregate subject to obtaining commitments from existing or new lenders for such increase and other conditions). The facilities will mature five years after the closing date of the Credit Agreement, subject to the lenders’ ability to extend the maturity date by one year if we request such an extension in accordance with the terms of the Credit Agreement, up to a maximum of two such extensions. At our option, amounts borrowed under the Credit Agreement bear interest at either the LIBOR rate or a fluctuating base rate, in each case, plus an applicable margin determined on a quarterly basis based on our consolidated ratio of total indebtedness to EBITDA (as calculated in accordance with the Credit Agreement). To date, we have elected to calculate interest on the outstanding balance at LIBOR plus an applicable margin. In connection with the Credit Agreement, we incurred debt issuance costs in June 2018 of $13.2 million, $12.6 million of which were capitalized and are being amortized over the term of the Credit Agreement. On January 24, 2019, we paid an upfront payment of $800.0 million related to our exclusive license agreement with Arena Pharmaceuticals, Inc. (Arena) and funded the payment by borrowing $800.0 million under the Credit Agreement. This brought our aggregate outstanding balance under the Credit Agreement to $1,050.0 million as of March 31, 2019. As we do not intend to repay the full outstanding balance within one year, the outstanding balance has been classified as long-term within the consolidated balance sheet. The Credit Agreement contains customary events of default and customary affirmative and negative covenants. As of March 31, 2019, we were in compliance with these covenants. Lung Biotechnology PBC is our only subsidiary that guarantees our obligations under the Credit Agreement though, from time to time, one or more of our other subsidiaries may be required to guarantee our obligations. During the three months ended March 31, 2019, we recorded $10.3 million of interest expense related to the Credit Agreement. During the same period in 2018, we recorded $2.6 million of interest expense related to a prior credit agreement.

7. Debt

Unsecured Revolving Credit Facility -- Credit Agreement

In June 2018, we entered into a credit agreement (the Credit Agreement) with Wells Fargo Bank, National Association (Wells Fargo), as administrative agent and a swingline lender, and various other lender parties, providing for (1) an unsecured revolving credit facility of up to $1.0 billion; and (2) a second unsecured revolving credit facility of up to $500.0 million (which facilities may, at our request, be increased by up to $300 million in the aggregate subject to obtaining commitments from existing or new lenders for such increase and other conditions). The facilities will mature five years after the closing date of the Credit Agreement, subject to the lenders’ ability to extend the maturity date by one year if we request such an extension in accordance with the terms of the Credit Agreement, up to a maximum of two such extensions.

At our option, amounts borrowed under the Credit Agreement bear interest at either the LIBOR rate or a fluctuating base rate, in each case, plus an applicable margin determined on a quarterly basis based on our consolidated ratio of total indebtedness to EBITDA (as calculated in accordance with the Credit Agreement). To date, we have elected to calculate interest on the outstanding balance at LIBOR plus an applicable margin. In connection with the Credit Agreement, we incurred debt issuance costs in June 2018 of $13.2 million, $12.6 million of which were capitalized and are being amortized over the term of the Credit Agreement.

On January 24, 2019, we paid an upfront payment of $800.0 million related to our exclusive license agreement with Arena Pharmaceuticals, Inc. (Arena) and funded the payment by borrowing $800.0 million under the Credit Agreement. This brought our aggregate outstanding balance under the Credit Agreement to $1,050.0 million as of March 31, 2019. As we do not intend to repay the full outstanding balance within one year, the outstanding balance has been classified as long-term within the consolidated balance sheet.

The Credit Agreement contains customary events of default and customary affirmative and negative covenants. As of March 31, 2019, we were in compliance with these covenants. Lung Biotechnology PBC is our only subsidiary that guarantees our obligations under the Credit Agreement though, from time to time, one or more of our other subsidiaries may be required to guarantee our obligations.

During the three months ended March 31, 2019, we recorded $10.3 million of interest expense related to the Credit Agreement. During the same period in 2018, we recorded $2.6 million of interest expense related to a prior credit agreement.