QLT Commences Phase III Clinical Trial For Photofrin(R) To Treat
Barrett's Esophagus
VANCOUVER, Jan. 7 /PRNewswire/ -- QLT PhotoTherapeutics Inc.,
(Nasdaq: QLTIF) a Canadian biotechnology company, today announced the
initiation of a Phase III pivotal clinical trial to investigate the use of its
light-activated drug, PHOTOFRIN(R), as a treatment for Barrett's esophagus, a
pre-cancerous condition that afflicts up to two million Americans.
The randomized Phase III trial will be conducted at approximately 30 sites
in North America and Europe, and will involve 200 patients with high-grade
dysplasia, which is the final stage of the abnormal tissue transformation
associated with Barrett's esophagus before the onset of esophageal cancer.
Although the trial is designed to measure response rates over a two year
period, the U.S. Food and Drug Administration (FDA) will consider an
accelerated approval process if satisfactory responses are achieved six months
after completion of patient enrollment. Both complete response and duration
of response will be evaluated.
Barrett's esophagus is a result of prolonged acid reflux (heartburn)
which causes the lining of the esophagus to be converted into tissue similar
to that which lines the stomach. This transformation makes the esophageal
tissue more susceptible to cancer. The incidence of Barrett's esophagus is
increasing steadily, particularly among middle-aged males with stressful
lifestyles and a mid to high socio-economic status.
An estimated 20 million Americans suffer from chronic heartburn,
10 to 13 percent of whom will develop Barrett's esophagus. Of these,
approximately 90 per cent have metaplasia, which is an early-stage abnormal
transformation of tissue, and 10 per cent have dysplasia. Patients with
dysplasia can be further broken down into low-grade dysplasia (60%) and
high-grade dysplasia (40%).
Patients with Barrett's esophagus have a 30 to 40 times greater chance of
developing esophageal cancer than people who do not have Barrett's esophagus.
There is currently no approved treatment to reverse the condition and decrease
the risk of developing cancer. Symptoms can be treated with a variety of acid
suppressants, but surgical removal of the esophagus, called an esophagectomy,
is currently the only curative treatment for patients with high-grade
dysplasia of Barrett's esophagus. Esophagectomy is associated with a known
relatively high mortality and morbidity, and a high cost of hospitalization.
QLT President and CEO, Dr. Julia Levy, said there are a number of reasons
why Barrett's esophagus is an ideal indication for PHOTOFRIN(R).
"First, development of PHOTOFRIN(R) for Barrett's esophagus is a natural
progression from esophageal cancer, where it is currently used.
"Secondly, the increasing incidence of Barrett's esophagus and subsequent
esophageal cancer will create a medical need for a treatment that is less
risky and less traumatic for patients than surgery, and less costly for
healthcare providers. As a minimally invasive out-patient procedure,
photodynamic therapy with PHOTOFRIN(R) meets these criteria.
"Thirdly, we believe PHOTOFRIN(R) is an ideal photosensitizer to treat
this condition because it has an appropriate depth of tissue penetration
thereby reducing the risk of perforation of the esophagus without negating
its potentially curative qualities."
In earlier clinical trials of PHOTOFRIN(R), based on a group of
55 patients with dysplasia or superficial esophageal cancer, preliminary
published results showed that the dysplasia was eliminated in 76% of patients,
and superficial cancer was successfully eliminated in all the patients who had
this diagnosis (7 patients).
PHOTOFRIN(R) has already been approved by the U.S. FDA for certain late
stage esophageal cancers.
In this phase III trial, PHOTOFRIN(R) is administered by intravenous
injection. Activation of PHOTOFRIN(R) by a non-thermal laser light, produced
by either Coherent Medical Group or Laserscope, produces a toxic form of
oxygen that destroys the tissue. The laser light is introduced through a
specially designed balloon catheter that smoothes the lining of the esophagus
to ensure even distribution of light.
QLT PhotoTherapeutics is a world leader in the development and
commercialization of proprietary pharmaceutical products for photodynamic
therapy, a field of medicine that utilizes light-activated drugs in the
treatment of cancer, diseases of the eye and other medical conditions. QLT's
lead product, PHOTOFRIN(R) has been approved for the treatment of various
cancers by regulatory authorities in the U.S., Canada, Japan and parts of
Europe. QLT's second-product, verteporfin (BPD-MA), is in final phases of
testing for the treatment of age-related macular degeneration.
The Company is listed on the NASDAQ National Market under the trading
symbol "QLTIF" and on The Toronto Stock Exchange under the trading symbol
"QLT".
The foregoing information contains forward-looking statements which
involve known and unknown risks, uncertainties and other factors which may
cause the actual results to be materially different from any future results,
performance or achievements expressed or implied by such statements. Such
factors include, those described in the Company's Annual Information Form, or
Form 10-K. Such factors include among others, the following: risks associated
with the commercialization of PHOTOFRIN(R) and verteporfin (BPD-MA);
uncertainties relating to product development, rapid technological change and
competition; uncertainty regarding patents and proprietary rights; product
liability claims and insurance; manufacturing uncertainties; uncertainty of
pricing and reimbursement; government regulation; and dependence on corporate
relationships.
SOURCE QLT PhotoTherapeutics Inc.
CONTACT: QLT Investor Relations: Elayne Wandler, Director,
Investor Relations & Corporate Communications, 604-872-7881, or
1-800-663-5486, Ewandler(at)qlt-pdt.com