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EXHIBIT 99.B

TRANSACTIONS IN THE STOCK BY THE REPORTING PERSONS

Trade Date	By	For the Account of	Quantity	Price per Share		Type of Trade	Broker
4/9/02	Partners	BVF	2,000	$	0.9500	Purchase	INET
4/10/02	Partners	BVF	8,800	$	0.9500	Purchase	INET
6/4/02	Partners	BVF	3,000	$	0.8800	Purchase	LTCO
6/5/02	Partners	BVF	3,000	$	0.8700	Purchase	LTCO
6/13/02	Partners	BVF	1,000	$	0.6500	Purchase	LTCO
6/13/02	Partners	BVF	6,100	$	0.6400	Purchase	INET
4/9/02	Partners	BVF2	1,000	$	0.9500	Purchase	INET
4/10/02	Partners	BVF2	6,000	$	0.9500	Purchase	INET
6/4/02	Partners	BVF2	2,000	$	0.8800	Purchase	LTCO
6/5/02	Partners	BVF2	2,000	$	0.8700	Purchase	LTCO
6/13/02	Partners	BVF2	1,000	$	0.6500	Purchase	LTCO
6/13/02	Partners	BVF2	4,000	$	0.6400	Purchase	INET
4/9/02	Partners	Investments	2,000	$	0.9500	Purchase	INET
4/10/02	Partners	Investments	13,000	$	0.9500	Purchase	INET
6/4/02	Partners	Investments	5,000	$	0.8800	Purchase	LTCO
6/5/02	Partners	Investments	5,000	$	0.8700	Purchase	LTCO
6/13/02	Partners	Investments	1,000	$	0.6500	Purchase	LTCO
6/13/02	Partners	Investments	9,000	$	0.6400	Purchase	INET
4/10/02	Partners	ILL10	1,000	$	0.9500	Purchase	INET
6/13/02	Partners	ILL10	1,000	$	0.6400	Purchase	INET

LTCO	=	Ladenburg Thalman
INET	=	Instinet

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