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PROTOX DOSES FIRST PATIENT IN BENIGN PROSTATIC HYPERPLASIA TRIAL USING PRX302

Vancouver, British Columbia, April 24, 2007 – ProtoxTM Therapeutics Inc. (TSX-V:PRX) today announced the enrolment and successful dosing of the first patient in a Phase I clinical study evaluating PRX302 to treat benign prostatic hyperplasia (BPH), commonly called enlarged prostate, a disease that affects one million Canadian men.

“This milestone represents a significant step towards a curative therapeutic option compared to currently available therapies,” said Dr. Fahar Merchant, President and CEO of Protox Therapeutics. ”PRX302 may offer a dramatic improvement in patient treatment and could therefore establish a new standard of care for a disease that affects tens of millions of men worldwide.”

BPH is characterized by difficulties in initiating or completing a urine stream and is often accompanied by painful symptoms. Oral medications, which address symptoms only, can cause unwanted side effects and become ineffective over time. Surgical procedures to treat elderly males with BPH are associated with complications and lengthy recovery times.

The first patient was treated at Can-Med Clinical Research in Victoria, British Columbia. A second clinical site has also been initiated at Urology Associates-Urologic Medical Research in Kitchener, Ontario.

Dr. Peter Pommerville, Principal Investigator at the Victoria site said, “The procedure went quite smoothly taking just ten minutes to conduct, under local anesthesia. The ease of administration means patients can resume their normal daily routine quite quickly and, more importantly, avoid the risks associated with surgery, notably the loss of sexual function.”

PRX302 is a pro-drug which is selectively activated by prostate specific antigen (PSA), an enzyme produced at elevated levels in patients with BPH or prostate cancer. Preclinical studies have shown that PRX302 can safely and effectively reduce prostate size, potentially decreasing pressure around the urethra and helping to restore normal urine flow. Interim results from an on-going Phase I trial to treat patients with prostate cancer show that PRX302 is safe and well-tolerated with encouraging signs of therapeutic activity.

In this new clinical study, PRX302 is being tested in a multi-centre, open-label dose escalation trial among male patients with symptomatic BPH who are not currently taking oral medication for their condition. The drug is delivered via two intraprostatic injections delivered transperineally. The primary objectives are to assess safety of and tolerability to PRX302 while secondary objectives will examine therapeutic activity including impact on symptoms and urinary flow. Up to 18 patients will be treated and actively followed for 90 days. Patient enrolment is expected to be completed before the end of the year.

About Protox
Protox Therapeutics is a leader in advancing novel, targeted therapeutics for treatment of cancer and other proliferative diseases. The company is actively developing two distinct but complementary platforms, INxin™ and PORxin™, and currently has four clinical programs in development. A Phase IIa clinical trial into the use of PRX321 (INxin) for the treatment of primary brain cancer has been completed and the drug has received Fast Track Designation and Orphan Drug Status from the US FDA. In addition, a Phase I trial has been completed for PRX321 to treat patients with renal cell carcinoma and non-small cell lung cancer. Patient enrolment is underway for two Phase I clinical trials using PRX302 (PORxin) for prostatic disease: one to treat localized prostate cancer and the other to treat benign prostatic hyperplasia.

About BPH
BPH is a common urological condition characterized by painful and bothersome symptoms that include difficulty in initiating a urine stream, a sense of urgency, leaking, dribbling and presence of blood in the urine. The condition affects over 50 million men throughout North America, Europe and Japan. More than half of all men will have symptoms of BPH by age 60 and as many as 90% may suffer from BPH after the age of 70. Left untreated, it can result in serious and possibly irreversible bladder damage. Current drug therapies only provide symptomatic relief and may trigger a range of side effects including impotence and hypotension. Surgical options such as TURP (transurethral resection of the prostate), which constitute the second-largest item in the US Medicare budget, can cause impotence, incontinence as well as other more serious procedure-related effects.

NO REGULATORY AUTHORITY HAS APPROVED OR DISAPPROVED THE CONTENT OF THIS RELEASE. THE TSX VENTURE EXCHANGE DOES NOT ACCEPT RESPONSIBILITY FOR THE ADEQUACY OR ACCURACY OF THIS RELEASE.

Certain statements included in this press release may be considered forward-looking. Such statements involve known and unknown risks, uncertainties and other factors that may cause actual results, performance or achievements to be materially different from those implied by such statements, and therefore these statements should not be read as guarantees of future performance or results. All forward-looking statements are based on Protox’ current beliefs as well as assumptions made by and information currently available to Protox and relate to, among other things, anticipated financial performance, business prospects, strategies, regulatory developments, market acceptance and future commitments. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this press release. Due to risks and uncertainties, including the risks and uncertainties identified by Protox in its public securities filings; actual events may differ materially from current expectations. Protox disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

For further information contact:

James Beesley
Director, Investor Relations
Protox Therapeutics
604-688-0199
jbeesley@protoxtherapeutics.com

Michael Moore
Investor Relations
Equicom Group
416-815-0700 x 241
mmoore@equicomgroup.com