[LETTERHEAD OF PRICEWATERHOUSECOOPERS] EXHIBIT 16.2 November 22, 1999 Securities and Exchange Commission 450 Fifth Street, N.W. Washington, D.C. 20549 Gentlemen: We have read the paragraph comprising Change in Independent Auditors included in the Form S-1 (Registration No. 333-89413) dated November 22, 1999, of Maxygen Inc. and are in agreement with the third through fifth sentences, as revised from the initial Form S-1 filing dated October 20, 1999, of the paragraph. We have no basis to agree or disagree with any other statements contained in that paragraph. Very truly yours, /s/ PricewaterhouseCoopers LLP