Posted on: 07/20/2006
Protox acquires Phase II cancer program from Neurocrine and U.S. Public Health Service
VANCOUVER, July 20 /CNW/ - Protox(TM) Therapeutics Inc. (TSX-V:PRX) today
announced that it has acquired a Phase II clinical stage program for the
treatment of cancer from Neurocrine Biosciences Inc. and the United States
Public Health Service (PHS). The targeted therapeutic toxin PRX321, formerly
known as NBI-3001, has received both Fast Track Designation and Orphan Drug
Status from the U.S. Food and Drug Administration (FDA) for primary brain
tumors. Fast Track Designation enables expedited review by the FDA of products
that are in clinical development and Orphan Drug Status provides a number of
benefits including seven years of market exclusivity.
"We have substantially expanded our clinical pipeline with the
acquisition of PRX321 and view this transaction as accelerating our path
toward becoming the world leader in the development of targeted toxin
therapeutics", said Dr. Fahar Merchant, President and Chief Executive Officer
of Protox. "This transaction transforms Protox into a company with a robust
clinical pipeline targeting serious indications such as brain, kidney,
prostate and lung cancers that have large unmet medical needs. Furthermore,
the acquisition of PRX321 provides us with encouraging human clinical data
from 86 cancer patients, a strengthened intellectual property portfolio of 14
patents issued worldwide and a technology which is supported by over 50
peer-reviewed scientific publications."
PRX321 is a targeted therapeutic toxin in which a cytokine, interleukin-4
(IL-4), is linked to a Pseudomonas exotoxin, a potent substance that can
destroy cancer cells. The IL-4 portion of the compound binds to IL-4 receptors
found on the surface of various types of cancer cells. The drug subsequently
enters the target cell where the toxin component causes cell death by
inhibiting protein synthesis. Besides brain, kidney and lung cancer, PRX321
has shown promising pre-clinical results in a number of cancers
over-expressing IL-4 receptors including pancreatic, ovarian, breast, head and
neck, melanoma, prostate and blood cancers such as chronic lymphocytic
leukemia (CLL) and Hodgkin's lymphoma.
In Phase I and II clinical trials for the treatment of primary brain
cancers, namely, glioblastoma multiforme (GBM) and anaplastic astrocytoma,
patients were administered PRX321 intra-tumorally. Results from these studies
demonstrated potent anti-tumor effects without drug-related systemic toxicity
in the majority of patients. Protox plans to conduct a Phase II dose-refining
clinical trial to optimize the dose for PRX321 in patients with primary brain
cancer. In another Phase I study, patients with recurrent or unresponsive
metastatic renal cell and non-small cell lung carcinomas were administered
escalating doses of PRX321 intravenously to determine the maximum tolerated
dose. Based on the results of this study, Protox plans to continue evaluation
of PRX321 in additional clinical trials for cancers that over-express IL-4
receptors, such as pancreatic cancer.
The PRX321 program was acquired by Protox in two separate transactions.
In the first transaction, Protox obtained exclusive worldwide rights to IL-4
fusion toxin technology (INxin(TM)) from PHS. In the second transaction,
regulatory and product assets were purchased from Neurocrine in order to
facilitate the continued development of PRX321. The assets purchased from
Neurocrine included two Investigational New Drug applications, Fast Track
Designation and Orphan Drug Status, as well as cGMP batches of PRX321 that may
potentially be used in future clinical trials. The IL-4 fusion toxin was
originally discovered and developed by Dr. Raj Puri, from the Center for
Biologics Evaluation and Research of the FDA and colleagues from the National
Cancer Institute (NCI). Subsequent development and clinical studies were
sponsored by Neurocrine and additional research continues at the FDA and NCI
under the direction of Dr. Puri.
Protox has committed to pay PHS and Neurocrine, for the license and
corresponding assets, up to US$2 million over the next three years. In
addition, Protox will pay PHS up to US$4 million in future milestone payments
(based on the compound receiving FDA approval for at least three indications),
as well as royalties on commercial sales.
Conference Call
Protox will hold a conference call and webcast to discuss this
announcement on July 20 at 4:30p.m. ET (1:30 p.m. PT). To access the
conference call, dial 416-644-3414 or 1-800-814-4861, or access the webcast on
the company's website at www.protoxtherapeutics.com. Please connect
approximately ten minutes prior to the beginning of the call to ensure
participation. The conference call will be archived for replay and can be
accessed by dialing 416-640-1917 or 1-877-289-8525 and enter the reservation
number 21197019 followed by the number sign, or via the company's website.
About Brain Cancers
Malignant gliomas such as GBM and anaplastic astrocytoma account for
around 45% of all primary brain cancers and are a leading cause of death from
cancer. The American Cancer Society estimates that in 2006 approximately
18,900 people will be diagnosed with brain cancer and almost 13,000 will die
because of the disease. Brain tumors are currently treated by surgical
removal, radiation or chemotherapy. Although treatment may prolong survival
somewhat, most malignant brain tumors are not curable. As such, a significant
unmet need exists for a minimally-invasive curative solution. IL-4 receptors
are expressed on the surface of malignant tumor cells but not on normal brain
cells. IL-4 fusion toxin has a very high affinity for IL-4 receptors and binds
tightly to IL-4 receptors on the surface of these tumor cells. The toxin
portion of the molecule is then selectively delivered into the tumor cells,
destroying the tumor while sparing healthy surrounding cells.
About Protox
Protox Therapeutics is a product-focused development-stage company and a
leader in advancing novel, targeted protein toxin therapeutics for treatment
of cancer and other proliferative diseases. The company currently has three
clinical programs in various stages of development for the treatment of
primary brain cancers, localized prostate cancer and cancers that over-express
IL-4 receptors. The company also has a pre-clinical program for benign
prostatic hyperplasia (BPH) that is expected to enter clinical trials. Through
the company's INxin and PORxin(TM) technology platforms, therapeutic
candidates are generated by engineering the naturally occurring toxins,
Pseudomonas exotoxin and proaerolysin. These drugs are potent anti-cancer
agents with distinct modes of action. INxin(TM) drugs target cancer cells that
produce specific tumor associated receptors on their cell surface. Once bound
to the cancer cells, INxin drugs enter the cell and inhibit protein synthesis
which ultimately leads to cell death. PORxin drugs are pro-drugs that are
activated by specific proteases produced at elevated levels by target cells.
Once activated, the drug punches holes in the cells causing the contents to
leak out and ultimately cell death.
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: visit our website at
www.protoxtherapeutics.com, or contact: Dr. Shafique Fidai, Senior Director of
Corporate Development, Protox Therapeutics, (604) 608-4222,
sfidai@protoxtherapeutics.com; Michael Moore, Investor Relations, The Equicom
Group, (416) 815-0700 x 241, mmoore@equicomgroup.com
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