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Exhibit 99B

EXHIBIT B
TRANSACTIONS IN THE STOCK BY THE REPORTING PERSONS

Trade Date	By	For the Account of	Quantity	Price per Share		Type of Trade	Broker
09/17/01	Partners	ILL10	5,000	$	2.5000	Sale	INET
09/21/01	Partners	BVF	140,000	$	0.6900	Purchase	WEED
09/21/01	Partners	BVF2	30,000	$	0.6900	Purchase	WEED
09/21/01	Partners	Investments	70,000	$	0.6900	Purchase	WEED
10/01/01	Partners	BVF2	27,000	$	0.8337	Purchase	INET
10/11/01	Partners	BVF2	4,400	$	1.0900	Purchase	INET
10/22/01	Partners	Investments	3,100	$	1.0300	Purchase	INET
10/23/01	Partners	Investments	61,200	$	1.0458	Purchase	INET
10/24/01	Partners	BVF2	1,500	$	1.0500	Purchase	HRZG
10/24/01	Partners	Investments	3,500	$	1.0500	Purchase	HRZG
10/26/01	Partners	Investments	10,000	$	1.1000	Purchase	INET
10/30/01	Partners	BVF	1,500	$	1.0756	Purchase	INET
10/30/01	Partners	ILL10	100	$	1.0756	Purchase	INET
10/30/01	Partners	BVF2	500	$	1.0756	Purchase	INET
10/30/01	Partners	Investments	1,500	$	1.0756	Purchase	INET
10/31/01	Partners	BVF	3,320	$	1.0900	Purchase	INET
10/31/01	Partners	BVF2	2,500	$	1.0900	Purchase	INET
10/31/01	Partners	Investments	8,500	$	1.0900	Purchase	INET
11/01/01	Partners	BVF	3,000	$	1.0900	Purchase	INET
11/01/01	Partners	BVF2	1,500	$	1.0900	Purchase	INET
11/01/01	Partners	Investments	3,500	$	1.0900	Purchase	INET
11/02/01	Partners	BVF2	2,000	$	1.0900	Purchase	INET
11/05/01	Partners	BVF	2,700	$	1.1218	Purchase	INET
11/05/01	Partners	Investments	3,000	$	1.1218	Purchase	INET
11/06/01	Partners	BVF2	14,400	$	1.1200	Purchase	INET
11/07/01	Partners	Investments	10,299	$	1.1000	Purchase	INET
11/08/01	Partners	ILL10	2,500	$	1.1000	Purchase	INET
11/16/01	Partners	Investments	6,100	$	1.0900	Purchase	INET

HRZG = Herzog, Heine & Geduld

INET = Instinet

WEED = Wheaton

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Exhibit 99B
EXHIBIT B TRANSACTIONS IN THE STOCK BY THE REPORTING PERSONS