8-K

                       SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

                                    FORM 8-K

                                 CURRENT REPORT

                     Pursuant to Section 13 or 15(d) of the
                         Securities Exchange Act of 1934


        Date of Report (Date of Earliest Event Reported): APRIL 11, 2001
                                                          --------------


                          TRANSKARYOTIC THERAPIES, INC.
- -------------------------------------------------------------------------------

             (Exact Name of Registrant as Specified in its Charter)


                                    DELAWARE
- -------------------------------------------------------------------------------

                 (State or Other Jurisdiction of Incorporation)


         000-21481                                      04-3027191
- ----------------------------------        -------------------------------------
  (Commission File Number)                    (IRS Employer Identification No.)


195 ALBANY STREET, CAMBRIDGE, MASSACHUSETTS                02139
- -------------------------------------------------------------------------------

(Address of Principal Executive Offices)                (Zip Code)


                                 (617) 349-0200
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               Registrant's Telephone Number, Including Area Code


                                 NOT APPLICABLE
- -------------------------------------------------------------------------------

          (Former Name or Former Address, if Changed Since Last Report)






Item 5.  OTHER EVENTS.
         ------------

         On April 11, 2001, Transkaryotic Therapies, Inc. ("TKT") announced that
the High Court of Justice in London has issued an opinion in a patent
infringement suit TKT and Aventis brought against Kirin-Amgen, Inc., involving
Dynepo(TM), the companies' Gene-Activated(R) erythropoietin FOR the treatment of
anemia.

         Mr. Justice Neuberger of the English High Court of Justice presided
over the case and ruled that one of four claims of European Patent No. 0 148
605 B2 asserted in the case against TKT and Aventis was not infringed on a
literal basis but would be infringed when the claim is construed on a
purposive basis (essentially under the U.K. version of the U.S. doctrine of
equivalents). The other three claims asserted were found to be invalid and
even if valid, incapable of infringement.

         The full text of TKT's press release issued in connection with the
foregoing matter is filed as Exhibit 99.1 to this Current Report on Form 8-K and
is incorporated herein by reference.

Item 7.  FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND EXHIBITS.
         ------------------------------------------------------------------

         (c)      Exhibits.

                  99.1 Press Release



                                      -2-




                                    SIGNATURE

         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.

Date: April 12, 2001                  REGISTRANT

                                          TRANSKARYOTIC THERAPIES, INC.


                                          By: /s/ DANIEL E. GEFFKEN
                                              -----------------------------
                                              Daniel E. Geffken
                                              Senior Vice President, Finance
                                              and Chief Financial Officer

                                      -3-




                                  EXHIBIT INDEX

EXHIBIT NUMBER                               DESCRIPTION

99.1                                         Press Release

                                      -4-

EX-99.1

                                                                    EXHIBIT 99.1

PRESS RELEASE

CONTACT:
Justine E. Koenigsberg
Director, Corporate Communications
(617) 349-0271


FOR IMMEDIATE RELEASE


     HIGH COURT OF JUSTICE ISSUES RULING IN ERYTHROPOIETIN PATENT LITIGATION

CAMBRIDGE, MA, APRIL 11, 2001 -- Transkaryotic Therapies, Inc. (Nasdaq: TKTX)
today announced the High Court of Justice in London has issued an opinion in a
patent infringement suit TKT and Aventis brought against Kirin-Amgen, Inc.,
involving Dynepo(TM), the companies' Gene-Activated(R) erythropoietin for the
treatment of anemia.

Mr. Justice Neuberger of the English High Court of Justice presided over the
case and ruled that one of four claims of European Patent No. 0 148 605 B2
asserted in the case against TKT and Aventis was not infringed on a literal
basis but would be infringed when the claim is construed on a purposive basis
(essentially under the U.K. version of the U.S. doctrine of equivalents). The
other three claims asserted were found to be invalid and even if valid,
incapable of infringement.

"We believe we made significant progress in this initial case and are confident
we have strong grounds to appeal the remaining issue," said Richard F Selden,
M.D., Ph.D., President and Chief Executive Officer of TKT. "The Judge found
critical facts in our favor, and we look forward to resolution of this case in
mid-2002."

Dynepo is a human erythropoietin for the treatment of anemia. Clinical
development testing Dynepo as a treatment for anemia of renal failure in
dialysis and pre-dialysis patients has been completed, and Aventis is pursuing
marketing authorization in the both U.S. and Europe.



Transkaryotic Therapies, Inc. (TKT) is a biopharmaceutical company dedicated to
the development and commercialization of products based on its three proprietary
development platforms: Gene-Activated(R) proteins, Niche Protein(TM) products,
and Gene Therapy. The Company's gene activation technology is a proprietary
approach to the large-scale production of therapeutic proteins, which does not
require the cloning of genes and their subsequent insertion into non-human cell
lines. TKT's Niche Protein product platform is based on protein replacement for
the treatment of rare genetic diseases, a group of disorders characterized by
the absence of certain metabolic enzymes. The Company's Gene Therapy technology,
known as Transkaryotic Therapy(TM), is focused on the commercialization of
non-viral, EX VIVO gene therapy products for the long-term treatment of chronic
protein deficiency states.



This press release contains forward-looking statements that involve a number of
risks and uncertainties. For this purpose, any statements contained herein that
are not statements of historical fact may be deemed to be forward-looking
statements. Without limiting the foregoing, the words, "believes,"
"anticipates," "plans," "expects," "estimates," "intends," "should," "could,"
"will," "may," and similar expressions are intended to identify forward-looking
statements. There are a number of important factors that could cause the
Company's actual results to differ materially from those indicated by such
forward-looking statements set forth under the caption "Certain Factors That May
Affect Future Results" in the Company's Annual Report on Form 10-K for the year
ended December 31, 2000 which is on file with the Securities and Exchange
Commission and incorporated herein by reference. These include, without
limitation, the following: (1) whether any of the Company's Gene-Activated
protein, Niche Protein or gene therapy product candidates will advance in the
clinical trial process, (2) whether such clinical trials will proceed in a
timely manner, (3) whether the clinical trial results will warrant continued
product development, (4) whether the required regulatory filings, such as
Investigational New Drug applications and Biologics License Applications, are
made in a timely manner, (5) whether the Company's products will receive
approval from the U.S. Food and Drug Administration or equivalent foreign
regulatory agencies, (6) if such products receive approval, whether they will be
successfully distributed and marketed, (7) whether patent litigation in which
the Company is involved or may become involved are resolved in a manner adverse
to the Company, (8) the effects of competitive products on the Company's
proposed products, and (9) the Company's dependence on third parties, including
collaborators, manufacturers and distributors.



         Gene-Activated(R) is a registered trademark and Niche Protein(TM),
         TKT(TM), and Transkaryotic Therapy(TM) are trademarks of Transkaryotic
         Therapies, Inc. Dynepo(TM) is a trademark of Aventis Pharma.



         Please visit our web site at www.tktx.com for additional information
         about Transkaryotic Therapies, Inc.