http://www.imclone.com/news.php

NEW YORK, Mar 05, 2008 (BUSINESSWIRE)– ImClone Systems Incorporated (NASDAQ: IMCL), a global leader in
the development and commercialization of novel antibodies to treat
cancer, today announced that the initial stage of a series of Phase
I/II clinical trials of IMC-A12, its anti-insulin-like growth factor-1
receptor (IGF-1R) monoclonal antibody, in children with relapsed or
refractory solid malignancies, has commenced patient enrollment. These
pediatric trials of IMC-A12 are being carried out by the Children's
Oncology Group (COG), an international research group that consists of
more than 240 centers that treat children and adolescents with cancer
in the United States, Canada, and other countries.

This study is the first of an initial stage of at least 10 Phase I
and II clinical trials of IMC-A12 sponsored by the Cancer Therapy
Evaluation Program (CTEP) of the Division of Cancer Treatment and
Diagnosis (DCTD), National Cancer Institute (NCI), to commence patient
enrollment. ImClone announced the selection of these proposals by NCI
in September 2007.

The insulin-like growth factor (IGF) system plays a critical role
in the development and progression of many types of cancer, including
many pediatric-specific cancers. The initial Phase I study, which will
be performed by the COG Phase I Consortium that includes 20 clinical
COG sites in North America, will determine the optimal dose, side
effects, pharmacology, and biological effects of IMC-A12 administered
intravenously once each week to children and adolescents with relapsed
or refractory solid cancers. Up to 38 patients are expected to be
enrolled. Immediately upon determination of a recommended pediatric
Phase II dose for IMC-A12, the antitumor activity of IMC-A12 will be
evaluated in a much larger Phase II study in a larger number of COG
sites. The Phase II study will evaluate the antitumor activity of
IMC-A12 in multiple pediatric malignancies, including osteosarcoma,
Ewing's sarcoma/peripheral primitive neuroectodermal tumor (PNET),
rhabdomyosarcoma, Wilms' tumor, and others.

“We are pleased to initiate the first of a series of NCI-sponsored
IMC-A12 trials and are particularly excited about this pediatric
study, as it is one of the first such studies of an IGF-IR inhibitor
ever undertaken in pediatric patients with cancer,” said Eric K.
Rowinsky, M.D., Chief Medical Officer and Executive Vice President of
ImClone Systems. “Evaluations of new cancer therapies in children
usually occur long after studies in adults and it is very gratifying
to begin directed studies of IMC-A12 in both adult and pediatric
patients at nearly the same time.”

IMC-A12 is a fully human IgG1 monoclonal antibody. It is designed
to specifically target the human IGF-1R, thereby inhibiting certain
ligands known as IGFs I and II from binding to and activating the
receptor. This action blocks a signaling pathway that enhances tumor
cell proliferation and survival. In 2007, ImClone completed enrollment
into two Phase I studies of IMC-A12, which demonstrated favorable
safety and pharmacokinetic profiles, as well as preliminary evidence
of antitumor activity as a single agent when administered either
weekly or every two weeks. In addition to the studies of IMC-A12 in
pediatric patients with advanced malignancies, Phase II studies of
IMC-A12 in patients with advanced prostate and colorectal cancers have
begun to enroll patients.

About ImClone's NCI-sponsored IMC-A12 Trials

In September 2007, the CTEP of the DCTD, NCI selected 10 proposals
for Phase I and II clinical trials of ImClone's IMC-A12, and several
other proposals have been selected since that time. The selection of
the proposed trials followed NCI's solicitation for specific
disease-directed studies among NCI investigators at academic
institutions, clinical trial consortia and NCI-sponsored oncology
cooperative clinical trial groups in the U.S. The selected trials
represent the first stage of clinical evaluations of IMC-A12 sponsored
by CTEP, NCI under a Clinical Trials Agreement between ImClone Systems
and DCTD, NCI to facilitate the clinical development of IMC-A12. Both
randomized and nonrandomized Phase II trials sponsored by CTEP will
explore the clinical activity, pharmacology and biological effects of
IMC-A12 as a single agent or combined with other relevant anticancer
agents in a wide range of malignancies including breast, lung,
pancreas and liver cancers, as well as both adult and pediatric
sarcomas. In addition, Phase I/II studies will evaluate the safety,
pharmacology, anticancer activity and biological effects of IMC-A12 in
children and adolescents with cancer, as well as in combination with
other novel targeting agents in which there is a specific rationale
for combined use.

About ImClone Systems

ImClone Systems Incorporated is a fully integrated
biopharmaceutical company committed to advancing oncology care by
developing and commercializing a portfolio of targeted biologic
treatments designed to address the medical needs of patients with a
variety of cancers. The Company's research and development programs
include growth factor blockers and angiogenesis inhibitors. ImClone
Systems' headquarters and research operations are located in New York
City, with additional administration and manufacturing facilities in
Branchburg, New Jersey. For more information about ImClone Systems,
please visit the Company's web site at

http://www.imclone.com

Certain matters discussed in this news release may constitute
forward-looking statements within the meaning of the Private
Securities Litigation Reform Act of 1995 and the Federal securities
laws. Although the company believes that the expectations reflected in
such forward-looking statements are based upon reasonable assumptions
it can give no assurance that its expectations will be achieved.
Forward-looking information is subject to certain risks, trends and
uncertainties that could cause actual results to differ materially
from those currently expected. Many of these factors are beyond the
company's ability to control or predict. Important factors that may
cause actual results to differ materially and could impact the company
and the statements contained in this news release can be found in the
company's filings with the Securities and Exchange Commission,
particularly those factors identified as “risk factors” in the
Company's most recent annual report of Form 10-K and in its quarterly
reports on Form 10-Q and current reports on Form 8-K. For
forward-looking statements in this news release, the company claims
the protection of the safe harbor for forward-looking statements
contained in the Private Securities Litigation Reform Act of 1995. The
company assumes no obligation to update or supplement any
forward-looking statements whether as a result of new information,
future events or otherwise.

SOURCE: ImClone Systems Incorporated

ImClone Systems Incorporated
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