Exhibit 15
July 28, 2006
To the Board of Directors and Shareholders of Schering-Plough Corporation:
We have made a review, in accordance with the standards of the Public Company Accounting Oversight Board (United States), of the unaudited interim financial information of Schering-Plough Corporation and subsidiaries for the three and six-month periods ended June 30, 2006 and 2005, as indicated in our report dated July 28, 2006 (which report included an explanatory paragraph regarding the Company’s adoption of Statement of Financial Accounting Standards No. 123 (Revised 2004), “Share-Based Payment”); because we did not perform an audit, we expressed no opinion on that information.
We are aware that our report referred to above, which is included in your Quarterly Report onForm 10-Q for the quarter ended June 30, 2006, is incorporated by reference in Registration StatementsNo. 2-83963,No. 33-50606,No. 333-30331,No. 333-87077,No. 333-91440,No. 333-104714,No. 333-105567,No. 333-105568,No. 333-112421,No. 333-121089 andNo. 333-134281 onForm S-8, Post Effective Amendment No. 1 to Registration StatementNo. 2-84723 onForm S-8, Post Effective Amendment No. 1 to Registration StatementNo. 333-105567 onForm S-8 and Registration StatementsNo. 333-12909,No. 333-30355, andNo. 333-113222 onForm S-3.
We also are aware that the aforementioned report, pursuant to Rule 436(c) under the Securities Act of 1933, is not considered a part of the Registration Statements prepared or certified by an accountant or a report prepared or certified by an accountant within the meaning of Sections 7 and 11 of that Act.
/s/ Deloitte & Touche LLP
Parsippany, New Jersey