Item 2.02. Results of Operations and Financial Condition.
On October 21, 2009, OSI Pharmaceuticals, Inc. ("OSI") issued a press release regarding its financial results for the quarter ended September 30, 2009. A copy of this release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.
As previously announced, OSI is holding a conference call, open to the public, to discuss these results at 5:00 p.m. (Eastern Time) on October 21, 2009. To access the live webcast or the archive via the Internet, log on to www.osip.com. Alternatively, please call 1-888-401-4689 (U.S.) or 1-719-457-2698 (international) to listen to the call. The conference ID number for the live call is 9702946. Telephone replay is available approximately two hours after the call through November 21, 2009. To access the replay, please call 1-888-203-1112 (U.S.) or 1-719-457-0820 (international). The conference ID number is 9702946.
The attached press release contains, and the conference call will contain, both generally accepted accounting principals, or GAAP, and non-GAAP financial measures for the quarter ended September 30, 2009. The non-GAAP financial measures include adjusted net income from continuing operations and adjusted earnings per share from continuing operations, each of which have directly comparable GAAP financial measures. OSI has provided these non-GAAP financial measures to adjust for the impact of the following expenses:
• equity-based compensation;

• imputed interest related to OSI's 2% Convertible Senior Subordinated Notes due 2025 and 3% Convertible Senior Subordinated Notes due 2038, which results from the application of Accounting Standards Codification Subtopic 470-20, which provides guidance for the bifurcation of the conversion feature from the debt component of convertible debt instruments that may be settled in cash upon conversion;

• amortization of acquired intangible assets;

• acquired in-process research and development;

• non-cash tax expense, which results in an adjustment of OSI's effective tax rate of approximately 39% to reflect its actual cash tax rate of approximately 3%; and

• restructuring and other costs related to OSI's consolidation of its U.S. operations.

These items have been adjusted because they are non-cash, non-recurring or not otherwise considered to be core to OSI's business. Management uses these non-GAAP financial measures internally to evaluate the performance of the business, including the allocation of resources as well as the planning and forecasting of future periods, and believes that these results are useful to others in analyzing the core operating performance and trends of OSI for the periods presented. Non-GAAP financial measures are not prepared in accordance with GAAP and therefore are not necessarily comparable to the financial results of other companies. These non-GAAP measures should be considered as a supplement to, not a substitute for or superior to, the corresponding financial measures calculated in accordance with GAAP.

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The non-GAAP financial measures included in the press release attached hereto as Exhibit 99.1, and in the conference call, have been reconciled to the comparable GAAP financial measures as required under the rules and regulations of the Securities Exchange Commission. These non-GAAP measures have limitations, however, because they do not include all items of income and expense that affect OSI, and therefore should not be considered in isolation of, or as an alternative to, measurements required by GAAP.
The information in this Item 2.02 (including Exhibit 99.1) is being "furnished" and shall not be deemed "filed" for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act") or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, whether made before or after the date of this report, except as shall be expressly set forth by specific reference in such filing. Item 9.01. Financial Statements and Exhibits.

Exhibit No. Description
99.1 Press release dated October 21, 2009.

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