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EXHIBIT 2

TRANSACTIONS IN THE STOCK BY THE REPORTING PERSONS
DURING THE PAST SIXTY DAYS

Trade Date	By	For the Account of	Quantity	Price per Share		Type of Trade	Broker*
3/19/2002	Partners	BVF	3,000	$	6.1750	Purchase	INET
3/20/2002	Partners	BVF	4,300	$	6.1194	Purchase	INET
3/21/2002	Partners	BVF	3,600	$	5.9654	Purchase	INET
3/22/2002	Partners	BVF	3,200	$	6.0000	Purchase	INET
3/25/2002	Partners	BVF	12,000	$	5.8936	Purchase	INET
3/26/2002	Partners	BVF	6,000	$	5.7110	Purchase	INET
3/27/2002	Partners	BVF	13,000	$	5.7222	Purchase	GKMC
3/28/2002	Partners	BVF	4,200	$	5.6233	Purchase	INET
3/28/2002	Partners	BVF	6,000	$	5.6400	Purchase	GKMC
4/1/2002	Partners	BVF	6,400	$	5.6420	Purchase	INET
4/2/2002	Partners	BVF	700	$	5.6426	Purchase	INET
4/2/2002	Partners	BVF	6,500	$	5.6500	Purchase	GKMC
4/3/2002	Partners	BVF	200	$	5.5100	Purchase	INET
4/3/2002	Partners	BVF	2,500	$	5.5500	Purchase	GKMC
4/4/2002	Partners	BVF	3,000	$	5.5200	Purchase	GKMC
4/8/2002	Partners	BVF	700	$	5.4600	Purchase	INET
4/8/2002	Partners	BVF	3,000	$	5.5000	Purchase	HRZG
4/9/2002	Partners	BVF	1,500	$	5.3755	Purchase	INET
4/9/2002	Partners	BVF	3,000	$	5.4000	Purchase	GKMC
4/10/2002	Partners	BVF	700	$	5.3900	Purchase	INET
4/10/2002	Partners	BVF	2,000	$	5.4500	Purchase	GKMC
4/11/2002	Partners	BVF	4,000	$	5.4100	Purchase	GKMC
4/12/2002	Partners	BVF	14,000	$	5.3335	Purchase	SLKC
4/12/2002	Partners	BVF	1,000	$	5.3500	Purchase	INET
4/12/2002	Partners	BVF	15,000	$	5.3960	Purchase	GKMC
4/15/2002	Partners	BVF	1,000	$	5.3200	Purchase	INET
4/16/2002	Partners	BVF	7,000	$	5.4448	Purchase	GKMC
4/16/2002	Partners	BVF	48,000	$	5.5200	Purchase	GROW
4/23/2002	Partners	BVF	10,300	$	3.5249	Purchase	INET
4/24/2002	Partners	BVF	11,000	$	2.9918	Purchase	GKMC
4/24/2002	Partners	BVF	4,800	$	2.9981	Purchase	INET
5/2/2002	Partners	BVF	5,600	$	2.7637	Purchase	INET
5/3/2002	Partners	BVF	4,000	$	2.5800	Purchase	OPCO
5/21/2002	Partners	BVF	150,000	$	2.2500	Purchase	COWN
3/19/2002	Partners	BVF2	2,000	$	6.1750	Purchase	INET
3/20/2002	Partners	BVF2	2,000	$	6.1194	Purchase	INET
3/21/2002	Partners	BVF2	3,000	$	5.9654	Purchase	INET
3/22/2002	Partners	BVF2	2,000	$	6.0000	Purchase	INET
3/25/2002	Partners	BVF2	8,000	$	5.8936	Purchase	INET
3/26/2002	Partners	BVF2	4,000	$	5.7110	Purchase	INET
3/27/2002	Partners	BVF2	9,000	$	5.7222	Purchase	GKMC
3/28/2002	Partners	BVF2	3,000	$	5.6233	Purchase	INET
3/28/2002	Partners	BVF2	4,000	$	5.6400	Purchase	GKMC
4/1/2002	Partners	BVF2	5,000	$	5.6420	Purchase	INET

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4/2/2002	Partners	BVF2	1,000	$	5.6426	Purchase	INET
4/2/2002	Partners	BVF2	5,000	$	5.6500	Purchase	GKMC
4/3/2002	Partners	BVF2	2,000	$	5.5500	Purchase	GKMC
4/4/2002	Partners	BVF2	2,000	$	5.5200	Purchase	GKMC
4/8/2002	Partners	BVF2	1,000	$	5.4600	Purchase	INET
4/8/2002	Partners	BVF2	2,000	$	5.5000	Purchase	HRZG
4/9/2002	Partners	BVF2	1,000	$	5.3755	Purchase	INET
4/9/2002	Partners	BVF2	1,000	$	5.4000	Purchase	GKMC
4/10/2002	Partners	BVF2	1,000	$	5.3900	Purchase	INET
4/10/2002	Partners	BVF2	1,000	$	5.4500	Purchase	GKMC
4/11/2002	Partners	BVF2	3,000	$	5.4100	Purchase	GKMC
4/12/2002	Partners	BVF2	10,000	$	5.3335	Purchase	SLKC
4/12/2002	Partners	BVF2	10,000	$	5.3960	Purchase	GKMC
4/16/2002	Partners	BVF2	5,000	$	5.4448	Purchase	GKMC
4/16/2002	Partners	BVF2	32,000	$	5.5200	Purchase	GROW
4/23/2002	Partners	BVF2	7,000	$	3.5249	Purchase	INET
4/24/2002	Partners	BVF2	7,000	$	2.9918	Purchase	GKMC
4/24/2002	Partners	BVF2	4,000	$	2.9981	Purchase	INET
5/2/2002	Partners	BVF2	4,000	$	2.7637	Purchase	INET
5/3/2002	Partners	BVF2	3,000	$	2.5800	Purchase	OPCO
5/21/2002	Partners	BVF2	60,000	$	2.2500	Purchase	COWN
3/19/2002	Partners	Investments	4,000	$	6.1750	Purchase	INET
3/20/2002	Partners	Investments	5,000	$	6.1194	Purchase	INET
3/21/2002	Partners	Investments	7,000	$	5.9654	Purchase	INET
3/22/2002	Partners	Investments	4,000	$	6.0000	Purchase	INET
3/25/2002	Partners	Investments	19,000	$	5.8936	Purchase	INET
3/26/2002	Partners	Investments	9,000	$	5.7110	Purchase	INET
3/27/2002	Partners	Investments	21,000	$	5.7222	Purchase	GKMC
3/28/2002	Partners	Investments	7,000	$	5.6233	Purchase	INET
3/28/2002	Partners	Investments	9,000	$	5.6400	Purchase	GKMC
4/1/2002	Partners	Investments	11,000	$	5.6420	Purchase	INET
4/2/2002	Partners	Investments	1,000	$	5.6426	Purchase	INET
4/2/2002	Partners	Investments	10,000	$	5.6500	Purchase	GKMC
4/3/2002	Partners	Investments	3,000	$	5.5500	Purchase	GKMC
4/4/2002	Partners	Investments	5,000	$	5.5200	Purchase	GKMC
4/8/2002	Partners	Investments	2,000	$	5.4600	Purchase	INET
4/8/2002	Partners	Investments	4,000	$	5.5000	Purchase	HRZG
4/9/2002	Partners	Investments	2,000	$	5.3755	Purchase	INET
4/9/2002	Partners	Investments	3,000	$	5.4000	Purchase	GKMC
4/10/2002	Partners	Investments	2,000	$	5.3900	Purchase	INET
4/10/2002	Partners	Investments	2,000	$	5.4500	Purchase	GKMC
4/11/2002	Partners	Investments	7,000	$	5.4100	Purchase	GKMC
4/12/2002	Partners	Investments	22,000	$	5.3335	Purchase	SLKC
4/12/2002	Partners	Investments	23,000	$	5.3960	Purchase	GKMC
4/16/2002	Partners	Investments	12,000	$	5.4448	Purchase	GKMC
4/16/2002	Partners	Investments	74,000	$	5.5200	Purchase	GROW

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4/23/2002	Partners	Investments	15,000	$	3.5249	Purchase	INET
4/24/2002	Partners	Investments	16,000	$	2.9918	Purchase	GKMC
4/24/2002	Partners	Investments	9,000	$	2.9981	Purchase	INET
5/2/2002	Partners	Investments	9,000	$	2.7637	Purchase	INET
5/3/2002	Partners	Investments	7,000	$	2.5800	Purchase	OPCO
5/21/2002	Partners	Investments	200,000	$	2.2500	Purchase	COWN

        *Broker Codes

COWN	—	Cowen & Co.
INET	—	Instinet
GKMC	—	Gerard Klauer
HRZG	—	Herzog Heine & Geduld
SLKC	—	Spear Leeds
GROW	—	Pacific Growth
OPCO	—	Oppenheimer & Co

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EXHIBIT 2