Revenue Recognition Collaboration and License Revenue In May 2014, the Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, or ASU, No. 2014-09, which amended the guidance for accounting for revenue from contracts with customers. This ASU superseded the revenue recognition requirements in ASC Topic 605, Revenue Recognition , or Topic 605, and created a new Topic 606, Revenue from Contracts with Customers , or Topic 606. Under Topic 606, an entity recognizes revenue when its customer obtains control of promised goods or services in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of Topic 606, the entity performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. At contract inception, once the contract is determined to be within the scope of Topic 606, we assess the goods or services promised within each contract and determine those that are performance obligations, then assess whether each promised good or service is distinct. When we offer options for additional goods or services, such as an option to license a drug in the future or for additional goods or services to be provided in the future, we evaluate whether such options are material rights that should be treated as additional performance obligations. We typically have not concluded that the option to license a drug or the options for additional goods or services that may be requested in the future under our collaboration agreement are material rights as the amounts attributable to such options represent standalone selling price, and therefore no consideration is allocated to these items at the inception of an agreement. When a partner exercises its option to license a drug or requests the additional goods or services, a new performance obligation is created for that item. Once performance obligations are identified, we then recognize as revenue the amount of the transaction price that we allocated to the respective performance obligation when (or as) each performance obligation is satisfied, either at a point in time or over time. If the performance obligation is satisfied over time, we recognize revenue based on the use of an output or input method. As of December 31, 2018, we have three revenue streams: our strategic collaboration, option and license agreement, or collaboration agreement, with Novartis Pharma AG, or Novartis, which we entered into in January 2017, our collaboration and license agreement with PTC Therapeutics International Limited, or PTC Therapeutics, which we entered into in August 2018 and commercial product revenue related TEGESDI sales subsequent to product launch in the fourth quarter of 2018. For a complete discussion of the accounting for our revenue streams, see Note 6, Strategic Collaboration with Novartis, Note 8, Collaboration and License Agreement with PTC Therapeutics , and Note 2, Summary of Significant Accounting Policies . Effective January 1, 2018, we adopted Topic 606 using the full retrospective transition method. Under this method, we revised our consolidated financial statements for prior period amounts including the periods included in this Report on Form 10-K, as if Topic 606 had been effective for such periods. The references as revised used herein refer to revisions of amounts originally reported for the year ended December 31, 2017 and as of December 31, 2017 as a result of our adoption of Topic 606. Impact of Adoption As a result of adopting Topic 606 on January 1, 2018, we revised our comparative financial statements for the prior years as if Topic 606 had been effective for that period. On September 18, 2018, we filed a Current Report on Form 8-K to present recast consolidated financial statements for each of the three years ended December 31, 2015, 2016 and 2017, to reflect our adoption of the new accounting standard for revenue recognition set forth in Topic 606. The financial information recast in the Form 8-K was originally filed with the SEC in our Annual Report on Form 10-K for the fiscal year ended December 31, 2017, which was filed with the SEC on February 28, 2018. Under Topic 605, we recognized revenue from our collaboration with Novartis over time on a straight-line basis. Under Topic 606, we recognize revenue from our collaboration with Novartis using the input method based on the total cost of performing services over time. As a result, the following financial statement line items for fiscal year 2017 were affected. Consolidated Balance Sheets December 31, 2017 (in thousands) As Revised Under Topic 606 As Originally Reported Under Topic 605 Effect of Change Current portion of deferred revenue $ 58,192 $ 50,579 $ 7,613 Long-term portion of deferred revenue 12,501 8,306 4,195 Accumulated deficit $ (296,221 ) $ (284,413 ) $ (11,808 ) Consolidated Statements of Operations and Comprehensive Loss Year Ended December 31, 2017 (in thousands, except per share data) As Revised Under Topic 606 As Originally Reported Under Topic 605 Effect of Change Research and development revenue under collaborative Agreement $ 43,401 $ 55,209 $ (11,808 ) Loss from operations (120,470 ) (108,662 ) (11,808 ) Net loss (121,559 ) (109,751 ) (11,808 ) Net loss per share of preferred stock, basic and diluted (1.80 ) (1.55 ) (0.25 ) Net loss per share of common stock owned by Ionis, basic and diluted (3.08 ) (2.82 ) (0.26 ) Net loss per share of common stock owned by others, basic and diluted $ (3.08 ) (2.82 ) $ (0.26 ) Consolidated Statement of Cash Flows Years Ended December 31, 2017 (in thousands) As Revised Under Topic 606 As Originally Reported Under Topic 605 Effect of Change Net loss $ (121,559 ) $ (109,751 ) $ (11,808 ) Adjustments to reconcile net loss to net cash used in operating activities: Deferred revenue 70,693 58,885 11,808 Cash, cash equivalents and restricted cash at beginning of period 7,857 7,857  Cash, cash equivalents and restricted at end of period $ 58,367 $ 58,367 $