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United States
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(AMENDMENT NO. 1)*
AVIRON
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(Name of Issuer)
COMMON STOCK, PAR VALUE $.001 PER SHARE
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(Title of Class of Securities)
05376210
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(CUSIP Number)
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(Date of Event Which Requires Filing This Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:
[ ] Rule 13d-1(b)
[X] Rule 13d-1(c)
[ ] Rule 13d-1(d)
*The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which would
alter the disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not be deemed
to be "filed " for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).
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CUSIP No. 053762100
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1. Names of Reporting Persons.
I.R.S. Identification Nos. of above persons (entities only).
BB BIOTECH AG
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2. Check the Appropriate Box if a Member of a Group (See
Instructions)
(a)
(b)
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3. SEC Use Only
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4. Citizenship or Place of Organization
SWITZERLAND
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Number of 5. Sole Voting Power
Shares Bene-
ficially -0-
Owned by Each
Reporting ----------------------------------------------------------
Person With:
6. Shared Voting Power
2,655,286
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7. Sole Dispositive Power
-0-
----------------------------------------------------------
8. Shared Dispositive Power
2,655,286
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9. Aggregate Amount Beneficially Owned by Each Reporting Person
2,655,286
10. Check if the Aggregate Amount in Row (11) Excludes Certain shares
11. Percent of Class Represented by amount in Row (11)
16.5%
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12. Type of Reporting Person (See Instructions) HC, CO
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Page 2 of 6 pages
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CUSIP No. 053762100
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1. Names of Reporting Persons.
I.R.S. Identification Nos. of above persons (entities only).
BIOTECH INVEST S.A.
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2. Check the Appropriate Box if a Member of a Group
(a)
(b)
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3. SEC Use Only
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4. Citizenship or Place of Organization
PANAMA
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Number of 5. Sole Voting Power
Shares Bene-
ficially -0-
Owned by Each
Reporting ----------------------------------------------------------
Person With:
6. Shared Voting Power
2,655,286
----------------------------------------------------------
7. Sole Dispositive Power
-0-
----------------------------------------------------------
8. Shared Dispositive Power
2,655,286
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9. Aggregate Amount Beneficially Owned by Each Reporting Person
2,655,286
10. Check if the Aggregate Amount in Row (11) Excludes Certain shares
11. Percent of Class Represented by amount in Row (11)
16.5%
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12. Type of Reporting Person
CO
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Page 3 of 6 pages
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CUSIP No. 053762100
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1. Names of Reporting Persons.
I.R.S. Identification Nos. of above persons (entities only).
BIOTECH TARGET S.A.
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2. Check the Appropriate Box if a Member of a Group
(a)
(b)
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3. SEC Use Only
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4. Citizenship or Place of Organization
PANAMA
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Number of 5. Sole Voting Power
Shares Bene-
ficially -0-
Owned by Each
Reporting ----------------------------------------------------------
Person With:
6. Shared Voting Power
-0-
----------------------------------------------------------
7. Sole Dispositive Power
-0-
----------------------------------------------------------
8. Shared Dispositive Power
-0-
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9. Aggregate Amount Beneficially Owned by Each Reporting Person
-0-
10. Check if the Aggregate Amount in Row (11) Excludes Certain shares
11. Percent of Class Represented by amount in Row (11)
0%
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12. Type of Reporting Person
CO
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Page 4 of 6 pages
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EXPLANATORY NOTE
Biotech Target S.A. ("Biotech Target") is a wholly-owned subsidiary of BB
Biotech AG ("BB Biotech"). Therefore, BB Biotech AG may be deemed to be the
beneficial owner of the shares of common stock of Aviron directly owned by
Biotech Target. For internal purposes, on June 18, 1998 BB Biotech caused
Biotech Target to transfer all of its holdings of securities issued by Aviron
(consisting of the 2,655,286 shares of common stock of Aviron) to another
wholly-owned subsidiary of BB Biotech, Biotech Invest S.A. ("Biotech Invest").
However, prior to the aforementioned transfer, as well as after the transfer of
shares from Biotech Target to Biotech Invest was completed, BB Biotech was, and
continues to be, the beneficial owner of the 2,655,286 shares of common stock
of Aviron which were previously directly owned by Biotech Target, and which
are now directly owned by Biotech Invest. The transfer to Biotech Invest
involves no change in BB Biotech's beneficial ownership of the 2,655,286 shares
of common stock of Aviron reported on this Schedule 13G.
ITEM 2.
(a) Name of Person Filing
BB Biotech AG
Biotech Invest S.A.
Biotech Target S.A.
(b) Address of Principal Business Office or, if none, Residence
BB Biotech Biotech Invest Biotech Target
Vordergasse 3 Swiss Bank Tower Swiss Bank Tower
8200 Schaffhausen Panama 1 Panama 1
CH/Switzerland Republic of Panama Republic of Panama
(c) Citizenship
See Item No. 4 of cover pages.
(d) Title of Class of Securities
Common Stock, Par Value $.001 Per Share
(e) CUSIP Number
053762-10-0
ITEM 4. OWNERSHIP
Provide the following information regarding the aggregate number and
percentage of the class of securities of the issuer identified in Item 1.
(a) Amount beneficially owned:
2,655,286
(b) Percent of class:
16.5%
(c) Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote
-0-
(ii) Shared power to vote or to direct the vote
2,655,286
(iii) Sole power to dispose or to direct the disposition of
-0-
(iv) Shared power to dispose or to direct the disposition of
2,655,286
ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED
THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY
This statement is filed jointly by BB Biotech, Biotech Invest and Biotech
Target. Biotech Target and Biotech Invest are wholly-owned subsidiaries of BB
Biotech.
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SIGNATURES
After reasonable inquiry and 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: August 13, 1998 By: /s/ Hans-Joerg Graf
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Name: Hans-Joerg Graf
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Signatory Authority
Date: August 13, 1998 By: /s/ Dr. Victor Bischoff
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Name: Dr. Victor Bischoff
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Vice Chairman and Director
BIOTECH TARGET, S.A.
Date: August 13, 1998 By: /s/ Dr. Andreas Bremer
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Name: Dr. Andreas Bremer
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Signatory Authority
Date: August 13, 1998 By: /s/ Dr. Anders Hove
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Name: Dr. Anders Hove
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Signatory Authority
Page 6 of 6 pages
