Exhibit 2.1
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                             Statement of Control Person


The Statement on this Schedule 13G/A dated October 4, 2001 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(c) and Rule
13d-1(k) respectively as a control person (HC) of Orbimed Advisors, LLC and
Orbimed Advisors, Inc.

Orbimed Advisors, Inc. files this statement on Schedule 13G/A in accordance with
the provisions of Rule 13d-1(b) and Rule 13d-1(k) respectively as an investment
advisor (IA) and Orbimed Advisors, LLC files this statement on Schedule 13G/A in
accordance with the provisions or Rule 13d-1(c) and 13d-1(k) respectively as a
corporation (CO).