1 EXHIBIT 16.2 [ANDERSEN LETTERHEAD] Office of the Chief Accountant Securities and Exchange Commission 450 Fifth Street, NW Washington, DC 20549 September 21, 2001 Dear Sir or Madam: We have read the Change in Independent Auditors paragraph included in the Registration Statement to be filed with the Securities and Exchange Commission and are in agreement with the statements contained therein. Very truly yours, Arthur Andersen LLP /s/ ARTHUR ANDERSEN LLP cg Copy to: Mr. Larry Richards Northwest Biotherapeutics