Basis of Presentation (Policies)

6 Months Ended

Jun. 30, 2021

Basis of Presentation [Abstract]

Basis of Presentation

We prepared the unaudited interim condensed consolidated financial statements for the three and six months ended June 30, 2021 and 2020 on the same basis as the audited financial statements for the year ended December 31, 2020, with the exception of our retrospective adoption of Accounting Standards Update, or ASU, 2020-06, which simplifies the accounting for convertible debt instruments. See Note 2, Significant Accounting Polices, Convertible Debt, for details of our adoption of this guidance. We included all normal recurring adjustments in the financial statements, which we considered necessary for a fair presentation of our financial position at such dates and our operating results and cash flows for those periods. Our operating results for the interim periods may not be indicative of what our operating results will be for the entire year. For more complete financial information, these financial statements, and notes thereto, should be read in conjunction with the audited financial statements for the year ended December 31, 2020 included in our Annual Report on Form 10-K filed with the Securities and Exchange Commission, or SEC.

Consolidation

In our condensed consolidated financial statements, we included the accounts of Ionis Pharmaceuticals, Inc. and the consolidated results of our wholly owned subsidiary, Akcea Therapeutics, Inc. and its wholly owned subsidiaries (“we”, “us” or “our”). We formed Akcea in December 2014. In July 2017, Akcea completed an initial public offering, or IPO, which reduced our ownership of Akcea’s common stock below 100 percent. In October 2020, we acquired the shares of Akcea’s common stock we did not own. We will refer to this transaction as the Akcea Acquisition throughout the remainder of this document. We reflected changes in our ownership percentage in our financial statements as an adjustment to noncontrolling interest in the period the changes occurred.