On November 4, 2019, the Company entered into a loan agreement with BioPharma Credit PLC (the “Collateral Agent”), and the Lenders (as defined therein), providing for up to $70.0 million in secured term loans to be advanced in up to three tranches (the “Loan Agreement”). As of June 30, 2020, the Company had borrowed an aggregate principal amount under the first tranche of $25.0 million (the “Tranche A Note Payable”), the second tranche of $25.0 million (the “Tranche B Note Payable”), and the third tranche of $20.0 million (the “Tranche C Note Payable”) under the Loan Agreement. On November 3, 2020, the Company, the Collateral Agent and the Lenders amended and restated the Loan Agreement, (as amended and restated, the “Amended and Restated Loan Agreement”), to provide for, among other things, an additional secured term loan of $150.0 million, or the Tranche D Loan. On November 18, 2020, the Company borrowed the Tranche D Loan (see Note 14, Long-Term Debt). The Company paid a commitment fee of 2.00% of the original $70.0 million committed facility amount in November 2019 and 2% of the $150.0 million Tranche D Loan in November 2020, as well as expenses incurred by the Lender in executing the agreements. The interest rate for the Tranche D Loan will be determined by reference to a Eurodollar rate plus 7.75% above such Eurodollar rate. The Eurodollar rate will have a 2.00% floor. The Tranche D Loan will be due in eight equal quarterly principal payments commencing on the 51st month anniversary of the date on which the Lenders fund the Tranche D Loan. All unpaid principal and interest under the Tranche D Loan will be due and payable on the 72nd month anniversary of the date on which the Lenders funded the Tranche D Loan.

On November 4, 2019, the Company also executed a purchase agreement (the “RPI Purchase Agreement”) with RPI. Pursuant to the RPI Purchase Agreement, the Company agreed to sell to RPI 6,666,667 shares of its common stock, a warrant to purchase up to 2,500,000 shares of common stock at an exercise price of $20.00 per share (the “Common Stock Warrant”), and all of the Company’s rights to receive royalties from Eisai with respect to net sales by Eisai of tazemetostat products in Japan pursuant to the Eisai License Agreement and any successor arrangement for Japan sales (the “Japan Royalty”, and collectively, the “Transaction”). In consideration for the sale of shares of common stock, the Common Stock Warrant and the Japan Royalty, RPI paid the Company $100.0 million upon the closing of the RPI Purchase Agreement. In addition, RPI agreed, in connection with RPI’s acquisition from Eisai of the right to receive royalties from the Company under the Eisai License Agreement, to reduce the Company’s royalty obligation by low single digits upon the achievement of specified annual net sales levels over $1.5 billion. In addition, under the RPI Purchase Agreement, the Company had the right to sell, and RPI had the obligation to purchase, subject to certain conditions, including a maximum purchase price of $20.00 per share, $50.0 million of shares of common stock at the Company’s option for an 18-month period from the date of execution of the RPI Purchase Agreement (the “Put Option”). In February 2020, the Company sold 2.5 million shares of its common stock to RPI, for an aggregate of $50.0 million in proceeds pursuant to the Put Option. Additionally, under the terms of the RPI Purchase Agreement, the founder and chief executive officer of RP Management, an affiliate of RPI, and a co-founder of Pharmakon Advisors LP, an affiliate of the Lenders, was elected as a director of the Company. As of June 30, 2022 and December 31, 2021, RPI and its affiliates owned approximately 18.9% and 8.6% of the Company’s common stock, respectively.

The Company accounted for the Loan Agreement and RPI Purchase Agreement as a single arrangement as RPI and the Lenders are related parties and the agreements were negotiated together. The aggregate proceeds of $125.0 million were allocated on a relative fair value basis, which approximated their respective actual fair values, to the four units of accounting pursuant to the transaction as follows: (1) $79.0 million to the common stock issued to RPI based on the closing price of the Company’s common stock on the date of the transaction, (2) $8.4 million to the Common Stock Warrant to purchase shares of common stock, based on the Black-Scholes option pricing model, (3) $12.6 million to the liability related to the sale of future royalties based on a discounted cash flow model and (4) $25.0 million to the Tranche A Note Payable based on the terms of the Loan Agreement. Transaction costs of $2.0 million were allocated directly to the units of accounting it relates to.

Although the Company sold all of its rights to receive the Japan Royalty, under the terms of the RPI Agreement, the Company continues to own all tazemetostat intellectual property rights and at execution had significant continuing involvement in the generation of these royalties. Due to the Company’s continuing involvement, the Company will continue to account for any royalties due as revenue and recorded the proceeds from this transaction as a liability (“Royalty Obligation”) that will be accreted using the effective interest method over the estimated life of the RPI Purchase Agreement.

As royalties are remitted to RPI from Eisai, the balance of the Royalty Obligation will be effectively repaid over the life of the Eisai License Agreement. In order to determine the accretion of the Royalty Obligation, the Company is required to estimate the total amount of future royalty payments to RPI over the life of the Eisai License Agreement. The $12.6 million recorded at execution will be accreted to the total of these royalty payments as interest expense over the life of the Royalty Obligation. At execution, the Company’s estimate of this total interest expense resulted in an effective annual interest rate of approximately 9.01%. This estimate contains significant assumptions that impact both the amount recorded at execution and the interest expense that will be recognized over the royalty period. The Company periodically assesses the estimated royalty payments to RPI from Eisai and to the extent the amount or timing of such payments is materially different than the original estimates, an adjustment is made to the effective interest rate, which will be recorded prospectively to increase or decrease interest expense. There are a number of factors that could materially affect the amount and timing of royalty payments to RPI from Eisai, and correspondingly, the amount of interest expense recorded by the Company, most of which are not within the Company’s control. Such factors include, but are not limited to, delays or discontinuation of development of tazemetostat in Japan, regulatory approval, changing standards of care, the introduction of competing products, manufacturing or other delays, generic competition, intellectual property matters, adverse events that result in governmental health authority imposed restrictions on the use of the drug products, significant changes in foreign exchange rates as the royalties remitted to RPI are made in U.S. dollars (USD) while the underlying Japan sales of tazemetostat will be made in currencies other than USD, and other events or circumstances that are not currently foreseen as tazemetostat is still under development in Japan and subject to regulatory approval. Changes to any of these factors could result in increases or decreases to both royalty revenues and interest expense. On June 23, 2021, Eisai announced that it had obtained manufacturing and marketing approval for the EZH2 inhibitor “Tazverik® Tablets 200 mg” (tazemetostat hydrobromide) in Japan with the indication of relapsed or refractory EZH2 gene mutation-positive FL (only when standard treatment is not applicable), which caused the Company to reassess the estimated future royalty payments to RPI. As of June 30, 2022, the Company’s assessment of the estimated future royalty payments to RPI resulted in a current effective interest rate of approximately 9.2%.

The following table shows the activity of the Royalty Obligation since the transaction inception through June 30, 2022:


	As of June 30, 2022
	(In thousands)
Proceeds from sale of future royalties	$	12,601
Non-cash royalty revenue		(93	)
Non-cash interest expense recognized		4,104
Liability related to the sale of future royalties - ending balance	$	16,612
Less current portion		(592	)
Related party liability related to sale of future royalties, net of current portion	$	16,020

During the three months and six months ended June 30, 2022, the Company recorded $40.0 thousand and $66.0 thousand, respectively, in non-cash royalties from net sales of tazemetostat in Japan. During the three and six months ended June 30, 2021, no non-cash royalties from net sales of tazemetostat in Japan were recorded. During the three and six months ended June 30, 2022, the Company recorded $0.4 and $0.7 million, respectively, of related non-cash interest expense. During the three and six months ended June 30, 2021, the Company recorded $0.5 and $0.9 million, respectively, of related non-cash interest expense.