Lorus Toxicology Program Supports Novel Route of Administration of the Anticancer Drug LOR-2040 in Bladder Cancer

TORONTO, ONTARIO, Aug 05 (MARKET WIRE) --
Lorus Therapeutics Inc. (TSX: LOR)(AMEX: LRP) ("Lorus"), a
biopharmaceutical company specializing in the research and development of
pharmaceutical products and technologies for the management of cancer,
today announced the successful completion of GLP toxicology studies to
explore a novel route of administration for its clinical-stage anticancer
drug, LOR-2040.

Two studies were conducted to assess toxicity of LOR-2040 when
administered by intravesical (direct) administration into the bladder. In
both studies, no evidence of toxicity was seen following single or
repeated doses of LOR-2040 given with this method of administration.
Toxicity was evaluated based on a wide range of observations including
detailed examination of urinary tract tissues.

The intravesical toxicology studies are the first assessment of local
tissue toxicity of this drug. LOR-2040 has previously demonstrated low
toxicity when administered intravenously, which is the current route of
administration for this drug in clinical trials.

Successful completion of these studies supports Lorus' plan to submit an
Investigational New Drug (IND) application for the use of LOR-2040 in the
treatment of bladder cancer during Q4, 2008.

"By completing this development program we have demonstrated that
LOR-2040 can be given safely with this new route of administration", said
Dr. Aiping Young, Lorus' President and CEO. "The results of these studies
provide further confirmation of the high safety profile seen with
LOR-2040 and of the potential utility of this drug for the treatment of
bladder cancer. I am pleased that we are on schedule to advance LOR-2040
for the treatment of this indication".

About LOR-2040

LOR-2040 (formerly GTI-2040) is an RNA-targeted drug that specifically
targets the R2 component of ribonucleotide reductase, which is required
for DNA synthesis and cell proliferation. Through downregulation of R2,
LOR-2040 has demonstrated strong antitumor and antimetastatic activity in
a variety of tumor types in both in vivo and in vitro models and is under
study in a multiple Phase I/II clinical program, including an advanced
Phase II clinical trial with LOR-2040 and high dose Ara-C (HiDAC) in
refractory and relapsed Acute Myeloid Leukemia (AML). The R2 target has
been described as a malignant determinant that is elevated in a wide
range of tumors, and can cooperate with a variety of cellular cancer
causing genes known as oncogenes to enhance tumor growth and metastatic
potential.

About Lorus

Lorus is a biopharmaceutical company focused on the research and
development of novel therapeutics in cancer. Lorus' goal is to capitalize
on its research, preclinical, clinical and regulatory expertise by
developing new drug candidates that can be used, either alone, or in
combination with other drugs, to successfully manage cancer. Through its
own discovery efforts and an acquisition and in-licensing program, Lorus
is building a portfolio of promising anticancer drugs. Lorus Therapeutics
Inc. is listed on the Toronto Stock Exchange under the symbol LOR, and on
the American Stock Exchange under the symbol LRP.

Forward Looking Statements

This press release may contain forward-looking statements within the
meaning of Canadian and U.S. securities laws. Such statements include,
but are not limited to, statements relating to: our research program
plans, our plans to conduct clinical trials, the successful and timely
completion of clinical studies and the regulatory approval process, our
ability to fund future research, our plans to obtain partners to assist
in the further development of our product candidates, the establishment
of corporate alliances, the Company's plans, objectives, expectations and
intentions and other statements including words such as "continue",
"believe", "plan", "expect", "intend", "will", "should", "may", and other
similar expressions. Such statements reflect our current views with
respect to future events and are subject to risks and uncertainties and
are necessarily based upon a number of estimates and assumptions that,
while considered reasonable by us are inherently subject to significant
business, economic, competitive, political and social uncertainties and
contingencies. Many factors could cause our actual results, performance
or achievements to be materially different from any future results,
performance, or achievements that may be expressed or implied by such
forward-looking statements, including, among others: our ability to
obtain the capital required for research and operations, the inherent
risks in early stage drug development including demonstrating efficacy,
development time/cost and the regulatory approval process; the progress
of our clinical trials; our ability to find and enter into agreements
with potential partners; our ability to attract and retain key personnel;
changing market conditions; and other risks detailed from time-to-time in
our ongoing quarterly filings, annual information forms, annual reports
and annual filings with Canadian securities regulators and the United
States Securities and Exchange Commission.

Should one or more of these risks or uncertainties materialize, or should
the assumptions set out in the section entitled "Risk Factors" in our
Annual Information Form underlying those forward-looking statements prove
incorrect, actual results may vary materially from those described
herein. These forward-looking statements are made as of the date of this
press release and we do not intend, and do not assume any obligation, to
update these forward-looking statements, except as required by law. We
cannot assure you that such statements will prove to be accurate as
actual results and future events could differ materially from those
anticipated in such statements. Investors are cautioned that
forward-looking statements are not guarantees of future performance and
accordingly investors are cautioned not to put undue reliance on
forward-looking statements due to the inherent uncertainty therein.

Lorus Therapeutics Inc.'s recent press releases are available through the
Company's website at www.lorusthera.com. For Lorus' regulatory filings on
SEDAR, please go to www.Sedar.com. For SEDAR filings prior to July 10,
2007 you will find these under the company profile for Global Summit Real
Estate Inc. (Old Lorus).

Contacts:
Lorus Therapeutics Inc.
Dr. Saeid Babaei
(416) 798-1200 ext. 490
Email: ir@lorusthera.com
Website: www.lorusthera.com

Copyright 2008, Market Wire, All rights reserved.

-0-