<PAGE> 1
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
SCHEDULE 13D
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(AMENDMENT NO. 2 )*
TRANSKARYOTIC THERAPIES, INC.
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(Name of Issuer)
COMMON STOCK, PAR VALUE $.01 PER SHARE
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(Title of Class of Securities)
893735100
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(CUSIP Number)
DR. ANDREAS BREMER
GRAFENAUWEG 4, 6301 ZUG CH/SWITZERLAND
011-41-41-724-5959
------------------
COPY TO:
DANIEL L. GOELZER, ESQ.
BAKER & MCKENZIE
815 CONNECTICUT AVENUE, N.W.
WASHINGTON, D.C. 20006
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(Name, Address and Telephone Number of Person Authorized to
Receive Notice and Communications)
MARCH 2, 1998
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(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 that is the subject of this Schedule 13D,
and is filing this schedule because of Sections 240.13d-1(e),
240.13d-1(f) or 240.13d-1(g), check the following box. [ ]
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CUSIP No. 893735100
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1. Names of Reporting Persons. BB BIOTECH AG
I.R.S. Identification Nos. of above persons (entities only).
NOT APPLICABLE: FOREIGN CORPORATION
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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
4. Source of Funds WC
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5. Check if Disclosure of Legal Proceeding Is Required Pursuant to Items
2(d) or 2(e)
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6. Citizenship or Place of Organization SWITZERLAND
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Number of 7. Sole Voting Power 0
Shares Bene- ------------------------------------------------------
ficially by 8. Shared Voting Power 2,811,500
Owned by Each ------------------------------------------------------
Reporting 9. Sole Dispositive Power 0
Person With ------------------------------------------------------
10. Shared Dispositive Power 2,811,500
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11. Aggregate Amount Beneficially Owned by Each Person reporting Person
2,811,500
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12. Check if the Aggregate Amount in Row (11) Excludes Certain shares
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13. Percent of Class Represented by amount in Row (11) 14.8%
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14. Type of Reporting Person HC, CO
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Page 2 of 5 pages
<PAGE> 3
CUSIP No. 893735100
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1. Names of Reporting Persons. BIOTECH TARGET S.A.
I.R.S. Identification Nos. of above persons (entities only).
NOT APPLICABLE: FOREIGN CORPORATION
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2. Check the Appropriate Box if a Member of a Group
(a)
(b)
- --------------------------------------------------------------------------------
3. SEC Use Only
4. Source of Funds AF
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5. Check if Disclosure of Legal Proceedings Is Required Pursuant to Items
2(d) or 2(e)
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6. Citizenship or Place of Organization PANAMA
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Number of 7. Sole Voting Power 0
Shares Bene- ------------------------------------------------------
ficially by 8. Shared Voting Power 2,811,500
Owned by Each ------------------------------------------------------
Reporting 9. Sole Dispositive Power 0
Person With ------------------------------------------------------
10. Shared Dispositive Power 2,811,500
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11. Aggregate Amount Beneficially Owned by Each Person reporting Person
2,811,500
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12. Check if the Aggregate Amount in Row (11) Excludes Certain shares
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13. Percent of Class Represented by amount in Row (11) 14.8%
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14. Type of Reporting Person CO
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Page 3 of 5 pages
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ITEM 5. INTEREST IN SECURITIES OF THE ISSUER
Items 5(a), 5(b) and 5(c) are hereby amended to read as follows:
(a) BB Biotech may be deemed to be the indirect beneficial owner of
the 2,811,500 shares of the common stock of Transkaryotic Therapies, Inc., par
value $.01 per share (the "Common Stock") directly beneficially owned by
Biotech Target as of May 26, 1998, which represent approximately 14.8% of the
outstanding shares of the Common Stock. No shares of the Common Stock are
directly beneficially owned by BB Biotech. To the best knowledge of BB Biotech
and Biotech Target, no director or executive officer of BB Biotech or Biotech
Target owns any shares of the Common Stock.
(b) The number of shares of the Common Stock to which there is sole
power to vote or to direct the vote, shared power to vote or to direct the
vote, sole power to dispose or to direct the disposition, or shared power to
dispose or direct the disposition, is set forth in the cover pages hereof and
such information is incorporated herein by reference. BB Biotech, through its
ownership of Biotech Target, may be deemed to indirectly beneficially own the
shares of the Common Stock which are directly beneficially owned by Biotech
Target within the meaning of Regulation 13D under the Exchange Act, and may be
deemed to share with Biotech Target the power to vote, or direct the vote of,
and the power to dispose of or direct the disposition of, the aggregate
2,811,500 shares of the Common Stock held directly by Biotech Target.
(c) Since January 2, 1998, Biotech Target engaged in the following
transactions with respect to the Common Stock. Each of these transactions was
completed on the NASDAQ stock market.
<TABLE>
<CAPTION>
=====================================================================================================================
DATE TRANSACTION AMOUNT PRICE PER SHARE
============================ ============================ ============================ ============================
<S> <C> <C> <C>
3/2/98 Bought 125,000 $32.38
3/2/98 Bought 78,000 $32.00
3/4/98 Bought 20,000 $31.75
3/4/98 Bought 50,000 $31.75
3/5/98 Bought 5,000 $31.50
3/6/98 Bought 40,000 $31.63
3/6/98 Bought 15,000 $31.63
3/25/98 Bought 5,000 $32.13
3/26/98 Bought 5,000 $32.13
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</TABLE>
Page 4 of 5 pages
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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: May 26, 1998 By: /s/ Hans-Joerg Graf
----------------------------
Name: Hans-Joerg Graf
Signatory Authority
Date: May 26, 1998 By: /s/ Dr. Victor Bischoff
----------------------------
Name: Dr. Victor Bischoff
Vice Chairman and Director
BIOTECH TARGET S.A.
Date: May 26, 1998 By: /s/ Dr. Andreas Bremer
----------------------------
Name: Dr. Andreas Bremer
Signatory Authority
Date: May 26, 1998 By: /s/ Dr. Anders Hove
----------------------------
Name: Dr. Anders Hove
Signatory Authority
Page 5 of 5 pages
