Confirmation of Participation In Stock Option Exchange Program

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Exhibit 99.(a)(1)(H)


MEMO TO: abM_1st_namebb abLast_Namebb
FROM:

Linda Powell
DATE:

, 2003
SUBJECT:

Confirmation of Participation in Stock Option Exchange Program


Thank you for your participation in Isis Pharmaceuticals, Inc.'s Stock Option Exchange Program. Defined terms not explicitly defined herein but defined in the Offer Document, shall have the same definitions as used in the Offer Documen ...