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News Release
Contact: Kurt Leutzinger, CFO
(510) 608-6575
or
Ina Cu-Unjieng, Manager, Investor/Public
Relations
(510) 608-4662
ABGENIX TO ACQUIRE IMMGENICS IN STOCK SWAP TRANSACTION
- COMPANY GAINS ACCESS TO PROPRIETARY HIGH THROUGH-PUT
ANTIBODY DISCOVERY TECHNOLOGY -
FREMONT, Calif. and VANCOUVER, B.C., September 26, 2000 - Abgenix, Inc. (Nasdaq:
ABGX) and ImmGenics, Inc. announced today a definitive agreement whereby Abgenix
will acquire ImmGenics in an all-stock transaction. The transaction, which is
expected to be completed by December 1, 2000, has been approved by both
companies' boards of directors and remains subject to ImmGenics shareholder
approval. Abgenix will exchange approximately US$77 million (CAN$110 million) of
its stock for all ImmGenics shares and options.
ImmGenics, founded in 1993, has developed a proprietary technology which can
increase both the effectiveness and speed of antibody product discovery efforts.
ImmGenics' technology dramatically increases the number of antibodies that can
be screened for any given antigen target. This breakthrough technology is
expected to allow Abgenix to rapidly select optimal product candidates from
larger pools of antibodies.
"Abgenix is very excited to be adding this powerful technology to our growing
collection of antibody product discovery tools," said R. Scott Greer, chairman
and CEO of Abgenix. "We intend to maintain our technological leadership in the
antibody field with both internal research initiatives and acquisitions. We also
look forward to integrating ImmGenics' high caliber employee group with the
Abgenix team."
"Abgenix, with its industry leading XenoMouse-TM- human antibody technology and
its commitment to enhancing antibody product discovery efforts, is the ideal
partner for ImmGenics," stated Kevin Leslie, Ph.D., ImmGenics' president and
CEO. "We enthusiastically anticipate combining our technology with Abgenix's
antibody product discovery program."
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Abgenix to Acquire ImmGenics, Page 2
ImmGenics' technology involves screening antibodies directly from
antibody-producing B cells rather than from hybridoma cell lines. This provides
a much larger pool of candidates than are available with traditional hybridoma
technology. ImmGenics' technology provides access to the complete immune
response for the identification of antibodies with the desired functional
properties and highest affinities. Abgenix estimates that this difference is
between 100 and 1000 fold. In addition to providing greater antibody diversity,
eliminating the hybridoma generation step will allow Abgenix to shorten product
development timelines.
"With exclusive access to ImmGenics' technology, Abgenix will be able to offer
unprecedented antibody diversity to specific antigen targets," stated C.
Geoffrey Davis, Ph.D., Abgenix's chief scientific officer. " By scanning the
entire immune repertoire of an immunized XenoMouse, this technology will allow
us to rapidly select the very best fully human antibodies, as defined by
specificity, functional properties, and affinity."
At the closing of the transaction, Abgenix will exchange approximately US$77
million (CAN$110 million) of Abgenix common stock, based on a 5-day average
price, for all outstanding ImmGenics shares and options. For accounting
purposes, the transaction will be treated as a purchase and the company will
incur a significant, yet-to-be-determined, one-time charge in the fourth
quarter, as well as ongoing amortization of goodwill. Operating expenses for
Abgenix are anticipated to increase modestly, by approximately US$2-3 million
annually as a result of this acquisition. Abgenix has a strong balance sheet
including $560 million in cash, cash equivalents and marketable securities at
June 30, 2000.
Abgenix is a biopharmaceutical company focused on the development and
commercialization of antibody therapies for a variety of diseases. The company
developed XenoMouse-TM- technology to enable the rapid generation of high
affinity, fully human antibody product candidates to essentially any disease
target appropriate for antibody therapy. Abgenix uses its XenoMouse technology
to build a large and diversified product portfolio through the establishment of
licensing arrangements with multiple pharmaceutical, biotechnology and genomics
companies and through the development of its own internal proprietary products.
For more information on Abgenix, visits the company's website at
WWW.ABGENIX.COM.
ImmGenics Pharmaceuticals Inc. is a Vancouver-based biotechnology company that
develops and intends to commercialize antibody-based therapeutic and diagnostic
products for the treatment and diagnosis of a wide variety of diseases,
including infectious diseases, cancer and inflammatory and autoimmune disorders.
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Abgenix to Acquire ImmGenics, Page 3
In conjunction with this press release, you are invited to listen to a
conference call with R. Scott Greer, CEO of Abgenix; C. Geoffrey Davis, Ph.D.,
Chief Scientific Officer of Abgenix; and Kevin Leslie, Ph.D., CEO of ImmGenics.
The conference call will be held on September 26, 2000 at 2:30 PM PST. To join
the conference call, dial (800) 553-0351 and mention the "Abgenix Conference
Call." For international callers, dial (612) 332-0228. An instant replay of the
call will be available by 6:00 PM on September 26, 2000. The replay number is
(800) 475-6701 for U.S. callers and (320) 365-3844 for international callers.
The replay access code is 540393.
STATEMENTS MADE IN THIS PRESS RELEASE ABOUT ABGENIX'S XENOMOUSE TECHNOLOGY,
PRODUCT DEVELOPMENT ACTIVITIES AND COLLABORATIVE ARRANGEMENTS OTHER THAN
STATEMENTS OF HISTORICAL FACT, ARE FORWARD LOOKING STATEMENTS AND ARE SUBJECT TO
A NUMBER OF UNCERTAINTIES THAT COULD CAUSE ACTUAL RESULTS TO DIFFER MATERIALLY
FROM THE STATEMENTS MADE, INCLUDING RISKS ASSOCIATED WITH THE SUCCESS OF
CLINICAL TRIALS, THE PROGRESS OF RESEARCH AND PRODUCT DEVELOPMENT PROGRAMS, THE
REGULATORY APPROVAL PROCESS, COMPETITIVE PRODUCTS, FUTURE CAPITAL REQUIREMENTS
AND THE EXTENT AND BREADTH OF ABGENIX'S PATENT PORTFOLIO. PLEASE SEE ABGENIX'S
PUBLIC FILINGS WITH THE SECURITIES AND EXCHANGE COMMISSION FOR INFORMATION ABOUT
RISKS THAT MAY AFFECT ABGENIX.
EXCEPT FOR THE HISTORICAL INFORMATION PRESENTED, THE MATTERS DISCUSSED IN THIS
PRESS RELEASE ARE FORWARD-LOOKING STATEMENTS THAT ARE SUBJECT TO CERTAIN RISKS
AND UNCERTAINTIES THAT COULD CAUSE ACTUAL RESULTS TO DIFFER MATERIALLY FROM ANY
FUTURE RESULTS, PERFORMANCE OR ACHIEVEMENTS EXPRESSED OR IMPLIED BY SUCH
STATEMENTS. SUCH RISKS AND UNCERTAINTIES INCLUDE POSSIBLE DELAYS OR FAILURE BY
IMMGENICS OR ITS PARTNERS TO DEVELOP AND/OR COMMERCIALIZE ANY TECHNOLOGY COVERED
BY A COLLABORATIVE AGREEMENT OR AGREEMENTS BETWEEN IMMGENICS AND ITS PARTNER OR
PARTNERS, POSSIBLE RISKS RELATED TO ADVERSE CLINICAL RESULTS AS PRODUCTS
INCLUDING ANY OF SUCH TECHNOLOGY MOVE INTO CLINICAL TRIALS, THE IMPACT OF
ALTERNATIVE TECHNOLOGICAL ADVANCES AND COMPETITION ON THE COLLABORATIVE
RELATIONSHIP BETWEEN THE PARTIES, INHERENT RISKS IN EARLY STAGE DEVELOPMENT OF
SUCH TECHNOLOGY.
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IMMGENICS TECHNOLOGY BACKGROUNDER
ImmGenics has developed a proprietary technology that enables
researchers to rapidly scan the entire immune repertoire of an immunized animal
and to select the B-cells producing antibodies with the desired functional
properties and the highest affinities in a matter of days. In terms of scope and
speed, the ImmGenics technology represents a significant advance over hybridoma
technology, the standard method for generating monoclonal antibodies as
practiced over the last twenty-five years. By combining this technology with
Abgenix's own XenoMouse technology, a large number of extremely high affinity,
fully human antibodies can be isolated within two to three months following the
first immunization.
HYBRIDOMA TECHNOLOGY
The development of hybridoma technology by Cesar Milstein and George Kohler in
1975 reshaped our thinking about the prospects of immunotherapy. Whereas
previously patients had been treated with complex, poorly characterized mixtures
of antibodies, usually in the form of horse serum, hybridoma technology offered
the possibility of establishing a single homogeneous cell line producing a
single antibody of a defined specificity - a "monoclonal antibody."
The first step in hybridoma technology is to repeatedly inject a mouse with a
target protein, the "antigen." Once the mouse's response has been determined to
be satisfactory, the antibody-producing B-cells are harvested and are fused with
an immortalized myeloma cell line. The resulting immortal "hybridomas" may
number from several hundred to several thousand. This number of
antibody-producing cells, limited by the inefficiency of the fusion process,
represents only a small fraction, on the order of one percent, of all the
antibody-producing B-cells originally in the mouse. While this small fraction is
usually adequate to produce quality antibodies, having access to the complete
immune response may allow identification of rare or special antibodies with
desired properties. For example, Abgenix believes that based upon ImmGenics'
experience with the technology, routine identification of antibodies with ultra
high affinities is possible.
IMMGENICS TECHNOLOGY
ADVANTAGES OVER HYBRIDOMA TECHNOLOGY: A significant advantage of
ImmGenics' technology is that the optimal antibody is selected from millions,
rather than hundreds to thousands, of antibody-producing B-cells derived from an
immunized mouse. This is accomplished by applying techniques for culturing the
B-cells directly, thus bypassing hybridoma technology with its inherent
inefficiency altogether. Using specially developed microplate-based assays, the
B-cells are rapidly assayed over a period of several days. Typically, thousands
of antigen-reactive cell-clones are identified, representing thousands of
individual antigen-specific monoclonal antibodies. The number of different
antigen-reactive monoclonal antibodies identified in a single experiment is
typically increased by 100-fold or more. After applying additional rapid
microplate-based assays to measure and rank antibodies by affinity and function,
individual B-cell clones producing extremely high quality antibodies can be
selected.
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Another significant advantage of ImmGenics' technology is that by
bypassing the hybridoma generation step, researchers can move rapidly into a
recombinant manufacturing cell line. Individual B cells selected using the
technology are isolated and the antibody genes can be directly introduced into a
manufacturing cell line. The resulting cell line then can be developed for
clinical trial testing over essentially the same timeline as that required for
hybridoma cell line development.
ADVANTAGES OVER PHAGE DISPLAY TECHNOLOGY: Phage display technology,
when applied to antibodies, also offers the potential of screening large numbers
of antibody clones. However, there are several drawbacks to this approach.
First, since for ethical reasons it is not practical to immunize humans, and the
phage library is derived from human immune tissue, the library is typically
"nonimmune." Therefore, the antibody response cannot be driven toward high
specificity and high affinity and is instead a result of random combinations and
mutagenesis. As a result, the antibodies derived from nonimmune human antibody
phage display libraries are typically of substantially lower affinity than those
derived from immunized donors. The combination of ImmGenics' technology with
XenoMouse provides full access to the repertoire of fully human antibodies that
have been naturally affinity matured in the mouse.
A second disadvantage of phage display is that the original pairing of
the antibody heavy and light chains, both chains of which contribute to the
antibody's binding affinity, is lost in the cloning process, and the probability
of restoring these original pairs is extremely low. As a result, significant
manipulation may be required to achieve affinity levels appropriate for clinical
trials. The combination of ImmGenics' technology and Abgenix's XenoMouse takes
advantage of the natural IN VIVO affinity maturation process and the maintenance
of the original heavy and light chain pairs.
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