X0303 4 2009-09-17 0 0000716646 CLINICAL DATA INC CLDA 0001091823 KIRK RANDAL J 1881 GROVE AVENUE RADFORD VA 24141 1 0 1 0 Common Stock 2009-09-17 4 A 0 18000 0 A 2311487 D Common Stock 1626722 I by Kirkfield Common Stock 183772 I by Zhong Mei Common Stock 242388 I by RJK 2000 Common Stock 48478 I by SenStaff08 Common Stock 48478 I by Staff08 Common Stock 24240 I by Incentive08 Common Stock 1096624 I by RJK Common Stock 1049877 I by NRM II Common Stock 692617 I by Staff01 Common Stock 290014 I by NRM III Common Stock 3380985 I by NRM V Randal J. Kirk controls each of Kirkfield, L.L.C. ("Kirkfield"), Zhong Mei, L.L.C. ("Zhong Mei"), Randal J. Kirk (2000) Limited Partnership ("RJK 2000"), Third Security Senior Staff 2008 LLC ("SenStaff08"), Third Security Staff 2008 LLC ("Staff08"), Third Security Incentive 2008 LLC ("Incentive08"), RJK, L.L.C. ("RJK"), New River Management II, LP ("NRM II"), Third Security Staff 2001 LLC ("Staff01"), New River Management III, LP ("NRM III") and New River Management V, LP ("NRM V"). Shares held by these entities may be deemed to be indirectly beneficially owned (as defined under Rule 13d-3 promulgated under the Securities Exchange Act of 1934, as amended) by Mr. Kirk. /s/ Randal J. Kirk 2009-09-21