Year Ended December 31,

Three Months Ended
March 31,

2011

2010

2009

2008

2007

2012

2011

(in thousands, except per share data)

Statement of Operations Data:

Revenue

$

435

$

2,474

$

1,258

$

3,781

$

493

$

114

$

57

Expenses

Research and development

44,182

39,706

13,681

15,790

4,751

5,183

14,864

General and administration

6,982

5,940

5,374

5,125

4,331

1,832

1,594

Acquired in-process research and development

—

—

9,000

—

—

—

—

Excess consideration paid over fair value

—

—

20,192

—

—

—

—

Licensing expense

50

269

300

836

—

—

—

Depreciation and amortization

148

168

137

43

90

31

42

Total expenses

51,362

46,083

48,684

21,794

9,172

7,046

16,500

Other (expense) income — Convertible note fair value adjustment

(23

)

(1,871

)

33

—

—

(3,210

)

(639

)

Other expense — Investment impairment charge

—

(286

)

—

—

—

—

—

Other interest (expense) income

(673

)

(675

)

(135

)

588

1,095

(124

)

(172

)

Other income

15

245

—

—

—

2

3

Net loss

$

(51,608

)

$

(46,196

)

$

(47,528

)

$

(17,425

)

$

(7,584

)

$

(10,264

)

$

(17,251

)

Basic and diluted net loss per common share*

$

(3.15

)

$

(4.21

)

$

(8.40

)

$

(3.83

)

$

(1.79

)

$

(0.53

)

$

(1.22

)

Weighted average number of common shares and common equivalent shares outstanding*

16,398

10,985

5,659

4,551

4,248

19,378

14,127

As of December 31,

As of March 31,

2011

2010

2009

2008

2007

2012

2011

(in thousands)

Balance Sheet Data:

Cash, cash equivalents and short-term investments

$

57,225

$

38,155

$

29,858

$

14,787

$

30,655

$

49,474

$

51,349

Total assets

62,380

44,767

36,437

17,679

31,241

54,575

56,805

Total current liabilities (includes short-term convertible senior notes in 2010)

7,228

8,183

3,930

3,853

1,516

6,085

12,633

Convertible senior notes, total long-term

17,337

17,436

16,676

—

—

10,494

18,037

Stockholders’ equity

37,815

19,147

15,830

13,826

29,725

37,996

26,136