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                                                                    EXHIBIT 99.1


                 ABGENIX ENTERS RESEARCH COLLABORATION WITH BASF

FREMONT, Calif., March 26 /PRNewswire/ -- Abgenix, Inc. (Nasdaq: ABGX - news)
today announced that it has signed a research collaboration agreement with BASF
Bioresearch Corporation ("BASF"). Under the agreement, BASF can utilize
Abgenix's XenoMouse (TM) technology to develop fully human antibodies to an
undisclosed antigen target. In return, Abgenix will receive an upfront research
payment and could receive additional fees and milestone payments plus royalties
on future product sales by BASF, if any. BASF will be responsible for product
development, manufacturing and marketing of any products developed through the
collaboration.

"We are pleased to add BASF, a large global pharmaceutical company, to our
growing list of corporate collaborators," stated R. Scott Greer, president and
chief executive officer of Abgenix. "We believe that this is evidence that the
pharmaceutical industry is increasingly recognizing the value of fully human
monoclonal antibodies as therapeutic products."

Abgenix is a biopharmaceutical company that develops and intends to
commercialize antibody therapeutic products for the treatment of a variety of
disease conditions, including transplant-related diseases, inflammatory and
autoimmune disorders, cardiovascular disease and cancer. Abgenix has developed
XenoMouse technology, which it believes enables quick generation of high
affinity, fully human antibody product candidates to essentially any disease
target appropriate for antibody therapy. Abgenix has collaborative arrangements
with multiple pharmaceutical and biotechnology companies involving its XenoMouse
technology. In addition, Abgenix has four proprietary antibody product
candidates that are under development internally, two of which are in human
clinical trials.

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 which may affect Abgenix.