Exhibit 2.1
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                           Statement of Control Person


The Statement on this Schedule 13G/A dated August 6, 2003 with respect to the
common stock par value $0.001 per share of SangStat Medical Corporation is filed
by Samuel D. Isaly in accordance with the provisions of Rule 13d-1(b) and Rule
13d-1(k), respectively, as a control person (HC) of OrbiMed Advisors LLC and
OrbiMed Advisors Inc.

OrbiMed Advisors Inc. and OrbiMed Advisors LLC file this statement on Schedule
13G/A in accordance with the provisions of Rule 13d-1(b) and Rule 13d-1(k),
respectively, as investment advisors (IA).