<PAGE> 1
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13D
(Amendment No. 1)
Under the Securities Exchange Act of 1934
AURORA BIOSCIENCES CORPORATION
------------------------------
(Name of Issuer)
COMMON STOCK, PAR VALUE $.001 PER SHARE
---------------------------------------
(Title of Class of Securities)
051920-10-6
-----------
(CUSIP Number)
DR. ANDREAS BREMER
GRAFENAUWEG 4, 6301 ZUG CH/SWITZERLAND
011-41-41-724-5959
------------------
(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)
Copy to:
Daniel L. Goelzer, Esq.
Baker & McKenzie
815 Connecticut Avenue, N.W.
Washington, D.C. 20006
JUNE 24, 1997
-------------
(Date of Event which Requires
Filing of this Statement)
If the filing person has previously filed a statement on Schedule 13G
to report the acquisition which is the subject of this Schedule 13D, and is
filing this schedule because of Rule 13d- 1(b)(3) or (4), check the following
box [ ].
Check the following box if a fee is being paid with the statement
[ ]. (A fee is not required only if the reporting person: (1) has a previous
statement on file reporting beneficial ownership of more than five percent of
the class of securities described in Item 1; and (2) has filed no amendment
subsequent thereto reporting
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beneficial ownership of five percent or less of such class.) (See Rule 13d-7.)
Note: Six copies of this statement, including all exhibits, should be
filed with the Commission. See Rule 13d-1(a) for other parties to whom copies
are to be sent.
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<TABLE>
<S> <C>
CUSIP No. 051920-10-6
- ---------
- --------------------------------------------------------------------------------
(1) Name of Reporting Person
BB Biotech AG
S.S. or I.R.S. Identification No. of Above Person
Not applicable: Foreign Corporation
- --------------------------------------------------------------------------------
(2) Check the Appropriate Box if a Member (a) [ ]
of a Group* (b) [X]
- --------------------------------------------------------------------------------
(3) SEC Use Only
- --------------------------------------------------------------------------------
(4) Source of Funds
WC
- --------------------------------------------------------------------------------
(5) Check Box is Disclosure of Legal Proceedings is required
Pursuant to Items 2(d) or 2(e) [ ]
- --------------------------------------------------------------------------------
(6) Citizenship or Place of Organization
Switzerland
- --------------------------------------------------------------------------------
Number of Shares (7) Sole Voting Power
Beneficially Owned 0 by BB Biotech AG
by Each Reporting ---------------------------------------
Person With (8) Shared Voting Power
1,421,500 by BB Biotech AG
(See Item 5)
---------------------------------------
(9) Sole Dispositive Power
0 by BB Biotech AG
---------------------------------------
(10) Shared Dispositive Power
1,421,500 by BB Biotech AG
(See Item 5)
- --------------------------------------------------------------------------------
(11) Aggregate Amount Beneficially Owned by Each Reporting Person
1,421,500 shares of common stock, par value of $.001 per share
(See Item 5).
- --------------------------------------------------------------------------------
(12) Check Box if the Aggregate Amount in Row (11)
</TABLE>
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<TABLE>
<S> <C>
Excludes Certain Shares* [ ]
- --------------------------------------------------------------------------------
(13) Percent of Class Represented by Amount in Row (11)
8.3%
- --------------------------------------------------------------------------------
(14) Type of Reporting Person*
HC, CO
- --------------------------------------------------------------------------------
</TABLE>
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<TABLE>
<S> <C>
CUSIP No. 051920-10-6
- ---------
- --------------------------------------------------------------------------------
(1) Name of Reporting Person
Biotech Target S.A.
S.S. or I.R.S. Identification No. of Above Person
Not applicable: Foreign Corporation
- --------------------------------------------------------------------------------
(2) Check the Appropriate Box if a Member (a) [ ]
of a Group* (b) [X]
- --------------------------------------------------------------------------------
(3) SEC Use Only
- --------------------------------------------------------------------------------
(4) Source of Funds*
AF
- --------------------------------------------------------------------------------
(5) Check box if disclosure of Legal Proceedings is Required
Pursuant to Items 2(d) or 2(e) [ ]
- --------------------------------------------------------------------------------
(6) Citizenship or Place of Organization
Panama
- --------------------------------------------------------------------------------
Number of Shares (7) Sole Voting Power
Beneficially Owned 0 by Biotech Target S.A.
by Each Reporting ----------------------------------
Person With (8) Shared Voting Power
1,421,500 by Biotech Target
S.A.(See Item 5)
----------------------------------
(9) Sole Dispositive Power
0 by Biotech Target S.A.
----------------------------------
(10) Shared Dispositive Power
1,421,500 by Biotech Target
S.A.(See Item 5)
- --------------------------------------------------------------------------------
(11) Aggregate Amount Beneficially Owned by Each Reporting Person
1,421,500 shares of common stock, par value of $.001 per share
(See Item 5).
- --------------------------------------------------------------------------------
</TABLE>
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(12) Check Box if the Aggregate Amount in Row (11)
Excludes Certain Shares* [ ]
- --------------------------------------------------------------------------------
(13) Percent of Class Represented by Amount in Row (11)
8.3%
- --------------------------------------------------------------------------------
(14) Type of Reporting Person*
CO
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ITEM 5. INTEREST IN SECURITIES OF THE ISSUER
(c) Biotech target has engaged in the following transactions during
the past sixty days:
<TABLE>
<CAPTION>
- --------------------------------------------------------
ACTION DATE NUMBER OF PRICE PER
SHARES SHARE
- --------------------------------------------------------
<S> <C> <C> <C>
Bought 6/24/97 1,100,000 $10.00
- --------------------------------------------------------
Bought 12/10/97 6,500 $12.88
- --------------------------------------------------------
Bought 12/11/97 10,000 $13.50
- --------------------------------------------------------
Bought 12/15/97 5000 $13.50
- --------------------------------------------------------
</TABLE>
<TABLE>
- ------------------------------------------------------
<S> <C> <C> <C>
Bought 12/17/97 250,000 $13.39
- ------------------------------------------------------
Bought 12/29/97 25,000 $13.19
- ------------------------------------------------------
Bought 1/2/97 25,000 $13.19
- ------------------------------------------------------
</TABLE>
Each of the listed transactions, unless otherwise noted, was completed on the
open market. As of December 31, 1997, BB Biotech and Biotech Target beneficially
own a total of 1,421,500 shares of the Common Stock, which represent
approximately 8.3% of the outstanding shares of Common Stock.
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SIGNATURES
After reasonable inquiry and to the best of my knowledge and
belief, I certify that the information set forth in this statement
is true, complete and correct.
BB BIOTECH AG
Date: January 12, 1997 By: /s/ Hans-Joerg Graf
-------------------------
Name: Hans-Joerg Graf
-----------------------
Date: January 12, 1997 By: /s/ Dr. Victor Bischoff
-------------------------
Name: Dr. Victor Bischoff
-----------------------
BIOTECH TARGET, S.A.
Date: January 12, 1997 By: /s/ Dr. Andreas Bremer
-------------------------
Name: Dr. Andreas Bremer
-----------------------
Date: January 12, 1997 By: /s/ Dr. Anders Hove
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Name: Dr. Anders Hove
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