June 15, 2007

 

 

 

United States Securities and Exchange Commission

Division of Corporate Finance

Attn:  Jim B. Rosenberg, Senior Assistant Chief Accountant

100 F Street, NE

Washington, D.C. 20549

 

Re:		Isis Pharmaceuticals, Inc.
		Form 10-K for the fiscal year ended December 31, 2006
		File No. 000-19125

 

Dear Mr. Rosenburg:

 

Pursuant to my conversation with Amy Bruckner, Staff Accountant, we respectfully request a one week extension to file our responses to your letter dated June 1, 2007. Accordingly, we will file our responses by June 22, 2007.

 

Should you have any questions regarding our request, please contact me at (760) 603-2492.

 

 

Sincerely,

 

 

 

/s/ Elizabeth L. Hougen
Elizabeth L. Hougen
Vice President, Finance and Chief Accounting Officer

 

cc:		B. Lynne Parshall, Esq.
		Grantland E. Bryce, Esq.