OMB
APPROVAL
|
OMB
Number: 3235-0145
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Expires:
February 28, 2009
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Estimated
average burden
hours
per response. . . 10.4
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[
]
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Rule
13d-1(b)
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[X]
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Rule
13d-1(c)
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[
]
|
Rule
13d-1(d)
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CUSIP
No. 03969P107
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13G
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Page
2 of 8
Pages
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||||
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||||||
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1.
|
Names
of Reporting Persons.
I.R.S.
Identification Nos. of above persons (entities only).
RA
Capital Management, LLC
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||||
|
||||||
2.
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Check
the Appropriate Box if a Member of a Group (See
Instructions)
|
|||||
(a)
o
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||||||
(b)
o
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||||||
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||||||
3.
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SEC
Use Only
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|||||
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||||||
4.
|
Citizenship
or Place of
Organization Massachusetts
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|||||
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||||||
Number
of
Shares
Beneficially
Owned
by
Each
Reporting
Person
With
|
5.
|
Sole
Voting
Power 1,494,762
|
||||
|
||||||
6.
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Shared
Voting
Power 0
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|||||
|
||||||
7.
|
Sole
Dispositive Power 1,494,762
|
|||||
|
||||||
8.
|
Shared
Dispositive
Power 0
|
|||||
|
||||||
9.
|
Aggregate
Amount Beneficially Owned by Each Reporting Person
1,494,762
|
|||||
|
||||||
10.
|
Check
if the Aggregate Amount in Row (9) Excludes o
Certain
Shares (See Instructions)
|
|||||
|
||||||
11.
|
Percent
of Class Represented by Amount in Row (9)
8.4%
|
|||||
|
||||||
12.
|
Type
of Reporting Person (See Instructions)
IA
|
|||||
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CUSIP
No. 03969P107
|
13G
|
Page
3 of 8
Pages
|
||||
|
||||||
|
1.
|
Names
of Reporting Persons.
I.R.S.
Identification Nos. of above persons (entities only).
Peter
Kolchinsky
|
||||
|
||||||
2.
|
Check
the Appropriate Box if a Member of a Group (See
Instructions)
|
|||||
(a)
o
|
||||||
(b)
o
|
||||||
|
||||||
3.
|
SEC
Use Only
|
|||||
|
||||||
4.
|
Citizenship
or Place of
Organization United
States
|
|||||
|
||||||
Number
of
Shares
Beneficially
Owned
by
Each
Reporting
Person
With
|
5.
|
Sole
Voting
Power 1,494,762
|
||||
|
||||||
6.
|
Shared
Voting
Power 0
|
|||||
|
||||||
7.
|
Sole
Dispositive
Power 1,494,762
|
|||||
|
||||||
8.
|
Shared
Dispositive
Power 0
|
|||||
|
||||||
9.
|
Aggregate
Amount Beneficially Owned by Each Reporting Person
1,494,762
|
|||||
|
||||||
10.
|
Check
if the Aggregate Amount in Row (9) Excludes o
Certain
Shares (See Instructions)
|
|||||
|
||||||
11.
|
Percent
of Class Represented by Amount in Row (9)
8.4%
|
|||||
|
||||||
12.
|
Type
of Reporting Person (See Instructions)
IN
|
|||||
|
CUSIP
No. 03969P107
|
13G
|
Page
4 of 8
Pages
|
||||
|
||||||
|
1.
|
Names
of Reporting Persons.
I.R.S.
Identification Nos. of above persons (entities only).
RA
Capital Healthcare Fund, L.P.
|
||||
|
||||||
2.
|
Check
the Appropriate Box if a Member of a Group (See
Instructions)
|
|||||
(a)
o
|
||||||
(b)
o
|
||||||
|
||||||
3.
|
SEC
Use Only
|
|||||
|
||||||
4.
|
Citizenship
or Place of
Organization Delaware
|
|||||
|
||||||
Number
of
Shares
Beneficially
Owned
by
Each
Reporting
Person
With
|
5.
|
Sole
Voting
Power 1,481,140
|
||||
|
||||||
6.
|
Shared
Voting
Power 0
|
|||||
|
||||||
7.
|
Sole
Dispositive
Power 1,481,140
|
|||||
|
||||||
8.
|
Shared
Dispositive
Power 0
|
|||||
|
||||||
9.
|
Aggregate
Amount Beneficially Owned by Each Reporting Person
1,481,140
|
|||||
|
||||||
10.
|
Check
if the Aggregate Amount in Row (9) Excludes o
Certain
Shares (See Instructions)
|
|||||
|
||||||
11.
|
Percent
of Class Represented by Amount in Row (9)
8.3%
|
|||||
|
||||||
12.
|
Type
of Reporting Person (See Instructions)
PN
|
|||||
|
CUSIP
No. 03969P107
|
13G
|
Page
5 of 8
Pages
|
||||
|
||||||
|
1.
|
Names
of Reporting Persons.
I.R.S.
Identification Nos. of above persons (entities only).
RA
Capital Healthcare Fund II, L.P.
|
||||
|
||||||
2.
|
Check
the Appropriate Box if a Member of a Group (See
Instructions)
|
|||||
(a)
o
|
||||||
(b)
o
|
||||||
|
||||||
3.
|
SEC
Use Only
|
|||||
|
||||||
4.
|
Citizenship
or Place of
Organization Delaware
|
|||||
|
||||||
Number
of
Shares
Beneficially
Owned
by
Each
Reporting
Person
With
|
5.
|
Sole
Voting
Power 13,622
|
||||
|
||||||
6.
|
Shared
Voting
Power 0
|
|||||
|
||||||
7.
|
Sole
Dispositive
Power 13,622
|
|||||
|
||||||
8.
|
Shared
Dispositive
Power 0
|
|||||
|
||||||
9.
|
Aggregate
Amount Beneficially Owned by Each Reporting Person
13,622
|
|||||
|
||||||
10.
|
Check
if the Aggregate Amount in Row (9) Excludes o
Certain
Shares (See Instructions)
|
|||||
|
||||||
11.
|
Percent
of Class Represented by Amount in Row (9)
0.1%
|
|||||
|
||||||
12.
|
Type
of Reporting Person (See Instructions)
PN
|
|||||
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CUSIP
No. 03969P107
|
Page 6
of
8
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CUSIP
No. 03969P107
|
Page 7
of
8
|
Item
6.
|
Ownership
of More than Five Percent on Behalf of Another
Person:
|
CUSIP
No. 03969P107
|
Page 8
of
8
|