Promega challenges LaRoche Taq polymerase patent

PromegaCC promegacc at
Tue Dec 20 11:29:30 EST 1994

Thought people might be interested in this item, could have some major
implications for PCR work.  This is taken from a press release. Note that
the data on which the patent challenge is based, including graphic files
of gels showing the patented Taq to be identical to one obtained by 'prior
art', is available by ftp from

Scientific Data Disputes Validity of Key Biotech Patent: 
Promega Files Brief in Federal Court Challenging 
U.S. Patent as European Application Nears Approval  

MADISON WI, December 20, 1994 -- Promega Corporation has filed a motion
the validity of the U.S. patent held by Swiss pharmaceutical conglomerate
Roche for Taq DNA Polymerase, a key enzyme used by life science
researchers around the 
Promega's motion, filed Thursday (December 15) in Federal Court in San
challenges U.S. Patent 4,889,818, issued December 26, 1989 to Cetus
Corporation of 
Emeryville, California, for Taq DNA Polymerase. In 1991, Hoffmann-LaRoche
Cetus, thus acquiring a presumably valid patent for Taq DNA Polymerase.
Promega was granted a license to manufacture and sell Taq DNA Polymerase
Cetus Corporation in 1990.  After its purchase of Cetus Corporation,
Hoffmann-La Roche 
asserted rights to the enzyme and filed suit against Promega in November
1992, alleging 
breach of the license agreement.  Promega first questioned and now
challenges the validity of 
the patent. Promega maintains that Taq DNA Polymerase was known before
"discovered" it, rendering meaningless the patent and any required
licensing for sale of the 
the enzyme.
Taq DNA Polymerase is a thermostable enzyme used in numerous scientific 
applications, including the Polymerase Chain Reaction (PCR), for which
Roche holds a second patent also acquired in the Cetus Corporation
Taq DNA Polymerase has become a standard reagent in research involving DNA

sequencing and used in research studying diseases such as cancer and AIDS.
While Roche claims a valid patent that gives it lucrative licensing
rights, Promega's 
lawsuit alleges invalidity of the patent because of: 1) the clear
existence of "prior art" (the 
earlier discovery of Taq DNA Polymerase) and 2) technical inaccuracies and

misrepresentations in the patent application filed by Cetus in August 1986
with the U.S. 
Patent and Trademark Office.
Promega also cites demonstrable error in the Hoffman-La Roche application
the European Patent Office in Munich, which is due to grant Hoffmann-La
Roche a patent 
effective early in 1995. A challenge to the American patent could cause
the European Patent 
Office to suspend or rescind its patent approval.
Promega's claim of prior art is substantiated in scientific publications
at the 
University of Cincinnati in the mid-1970s and by Soviet researchers in
Moscow in 1980.  
The motion and supporting brief identify the clear existence of prior art
in a thesis authored 
by David Edgar in 1974 (a reference that was not before the Patent
Examiner).  Later work 
published in an article in The Journal of Bacteriology in 1976  attributed
to Alice Chien 
and Dr. John Trela of the University of Cincinnati, as well as work
published in 
Biokhimiya  and Biochemistry  in 1980 by Dr. Alexei Kaledin, S.I.
Gorodetskii and A.G. 
Slyusarenko of Moscow are cited. 
A panel of respected scientific experts from the life science community,
Nobel Laureate Dr. Arthur Kornberg,  support Promega's brief.  Promega's
motion includes 
data prepared by Drs. Kornberg, Thomas A. Kunkel and Dale W. Mosbaugh.  
In addition, Promega has made public the scientific data supporting its
position.  The data 
includes: 1) reproduction of all of the prior art purification methods
originally reported 
in Edgar's 1974 thesis, Chien's 1976 paper, and the Kaledin paper in 1980
(2 independent 
laboratories);  2) comparison of the enzyme obtained from each of the
prior art methods in 
side by side tests with the patented nTaq and rTaq; and  3) demonstrations
representations to the patent office of differences between the patented
and the prior art 
polymerases made during prosecution of the patent application are false.
Promega has made public its motion and supporting documentation to assist
the scientific community, as well as the general public, to gain a better
understanding of the 
legal and scientific issues in the case, explained William Linton,
President and CEO. "It is 
important for us at this time to bring forth the clear and compelling
scientific basis for our 
challenge of the Taq patent issued in the U.S. While Promega strongly
supports and respects 
the patenting of original and novel inventions, we also believe that
scientists in this country 
should not be forced to pay a premium simply because a patent was granted
based on 
erroneous and misleading information." 
 A finding of invalidity of the patent could have far reaching effects on
the future purchase 
and use of Taq DNA Polymerase in basic and applied research. 

#     #     #

InterNet access to a summary of the Promega legal brief and information on
how to access the 
filed legal documents and supporting scientific data is available through
anonymous FTP login at 
FTP.PROMEGA.COM.  Please use your E-mail address as a password to gain

  Edgar, David B. "DNA Polymerase from an Extreme Thermophile: Thermus
aquaticus" (1974)
  Chien, Alice et al. "Deoxyribonucleic Acid Polymerase from the Extreme
Thermophile Thermus 
aquaticus," Journal of Bacteriology 127: 1550-1557 (1976). 
  Kaledin, Dr. Alexei et al. "Isolation and Properties of DNA Polymerase
from Extremely Thermophilic 
Bacterium Thermus aquaticus YT1," Biokhimiya 45: 644-651 (1980). 
  Kaledin, Dr. Alexei et al. "Isolation and Properties of DNA Polymerase
from Extremely Thermophilic 
Bacterium Thermus aquaticus YT1," Biochemistry 45: 494-501 (1980).

For further information, contact: 
Bob Benjamin, Hill & Knowlton, Inc., at (312) 565-1200 or FAX (312)

Len Walker, Director of Corporate Communications, Promega Corporation 
at (608) 277-2683 or InterNet mail via LWALKER at PROMEGA.COM.


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