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                                                              EXHIBIT 99.01


                                 NeoPharm, Inc.
                           150 Field Drive, Suite 195
                              Lake Forest, IL 60045




April 1, 2002



Securities and Exchange Commission
450 5th Street NW
Washington, DC  20549

Ladies and Gentlemen:

Pursuant to Securities and Exchange Commission Release Nos. 33-8070; 34-45590;
35-27503; 39-2395; IA-2018; IC-25464; FR-62; File No. S7-03-02, this letter is
to confirm that NeoPharm, Inc. has received assurance from its independent
public accountants, Arthur Andersen LLP ("Andersen"), that Andersen's audit of
our consolidated financial statements as of December 31, 2001 and for the year
then ended (the "Audit") was subject to Andersen's quality control system for
the U.S. accounting and auditing practice to provide reasonable assurance that
the engagement was conducted in compliance with professional standards, that
there was appropriate continuity of Andersen personnel working on the Audit,
availability of national office consultation, and availability of personnel at
foreign affiliates of Andersen to conduct the relevant portions of the Audit.

NeoPharm, Inc.

/s/ Lawrence A. Kenyon

Lawrence A. Kenyon
Chief Financial Officer