HERE AT THE MOSS REPORTS
Constantly monitoring the scientific literature pertaining
to the prevention and treatment of cancer is an essential
part of my work. By keeping a watchful eye on the medical
journals I am able to discern emerging research ideas and
pass along to my readers the latest developments. It also
enables me to keep the library of Moss
Reports on more than 200 different cancer diagnoses
updated.
Each Moss Report is an even-handed
and thorough analysis of the available conventional and alternative
treatments for a particular kind of cancer. The reports also
discuss such topics as participation in clinical trials, how
to change one's diet in order to maximize one's chances of
recovery, and how to detect and avoid unsafe and unsound remedies.
If you would like to order a Moss
Report for yourself or someone you love, you can do
so from our website, www.cancerdecisions.com,
or by calling 1-800-980-1234 (814-238-3367
from outside the US).
Also downloadable from our website are our Current
Topics reports on important cancer-related subjects.
These reports are priced at $9.95 each.
Choose from the following:
I am also available for phone consultations
with those clients who have purchased a Moss
Report. A recent phone consultee wrote:
"Following my diagnosis of stage IV breast cancer
and prior to deciding on my first courses of treatment,
I found educating myself on cancer and my possible treatment
options overwhelming. I researched many sources of information
and have found Dr. Moss' books and newsletter the most informative
and current. Even more so was the benefit gained from my
telephone consultation. He will help you weed through all
the non-pertinent issues regarding your particular type
of cancer and save you immeasurable time and effort. I have
truly benefited from Dr. Moss' exceptional education and
experience. No comment would be complete without noting
the professional and courteous manner afforded me by the
entire staff at Cancer Decisions." — I.T.
To schedule a phone consultation, please call 1-800-980-1234
(814-238-3367 from outside the US) or send an email to Jacquie@cancerdecisions.com.
We look forward to helping you.
A NEW DRUG FOR ADVANCED KIDNEY CANCER—BUT DOES IT
WORK?
On July 27, 2006, the European Union (EU) followed America's
lead and gave conditional approve to Pfizer's new drug Sutent
(sunitinib, formerly known as SU11248) as a treatment for
advanced kidney cancer. The drug is also being used as a treatment
for a rare type of cancer known as gastrointestinal stromal
tumor (GIST).
But how effective is it?
Sutent is one of the latest crop of 'targeted' therapies
for various kinds of cancer. It is given as a 50 milligram
(mg) pill once per day. Technically speaking, it contains
small-molecule inhibitors of the tyrosine kinase portion of
the VEGF and PDGF receptors.
According to a June 2006 report from Memorial Sloan-Kettering
Cancer Center (MSKCC), New York, 106 patients with advanced
kidney cancer were treated there with Sutent. The objective
partial response rate was 34 percent, while the median progression-free
survival time was 8.3 months (ranging from 7.8 to 14.5 months).
The most common adverse affects were fatigue (28 percent)
and diarrhea (20 percent). Laboratory abnormalities seen in
patients included neutropenia (white blood cell depletion)
in 42 percent of patients, an elevation of the enzyme lipase
(28 percent), and anemia (26 percent).
The authors of this report call these findings proof of the
"efficacy and manageable adverse-event profile"
of Sutent in the treatment of advanced kidney cancer. But
the astute reader will notice that there is no mention of
overall survival in the above report. It has in fact been
dropped even as a measurable endpoint for the study. This
is in line with FDA officials' increasingly frequent policy
of approving drugs based on what are called "surrogate"
(i.e., substitute, or stand-in) endpoints, such as objective
partial responses or progression-free survival, which do not
equate to, or reflect, an improvement in overall survival.
(An objective partial response is generally defined as the
shrinkage of measurable tumors by more than 50 percent for
a period of one month or more. But simply because a patient's
tumors have temporarily shrunk does not in and of itself mean
that the patient will live longer.)
Since the MSKCC study of Sutent was a phase II non-randomized
study, with no concurrent comparison group, it is not valid
to draw the conclusion that these patients did better than
those who might have received an alternate treatment or no
further treatment at all.
At the 2006 meeting of the American Society for Clinical
Oncology (ASCO) there was an additional report on a phase
III trial comparing Sutent to a more traditional therapy,
interferon-alpha, in previously untreated (so-called "treatment-naïve")
patients with metastatic renal cell carcinoma (RCC). Untreated
patients who had clear-cell, metastatic renal cell cancers
received either either Sutent or interferon-alpha. Sutent
was given in six week cycles of 50 milligrams (mg) orally
once per day for four weeks, followed by two weeks off. The
interferon-alpha patients received subcutaneous injections
of 9 million units (MU) given three times per week.
Between August 2004 and October 2005, 750 patients were randomized
to one or other of these two groups. The median progression-free-survival
(PFS) was 47.3 weeks for Sutent vs. 24.9 weeks for interferon-alpha.
(Progression-free survival is a term that describes the length
of the interval during which the disease is stabilized before
it begins to advance again.) The respective objective response
rates were 24.8 percent for Sutent vs. 8.8 percent for interferon-alpha
- i.e., 24.8 percent of the patients who were given Sutent
exhibited a temporary shrinkage of their tumors, while tumor
shrinkage was seen in only 8.8 percent of patients given interferon-alpha.
At the time of the report, in June 2006, there had been 49
deaths out of 375 patients in the Sutent group vs. 65 deaths
in the equally large interferon-alpha group. Overall survival
was included as one of the primary endpoints in this study.
However, when it came time to evaluate the study, the authors
provided only figures on progression-free survival, and, curiously,
none on overall survival. But since the survival trend did
seem to favor Sutent it is possible that some future evaluation
may indeed demonstrate such an effect.
New drugs to treat intractable forms of cancer, such as metastatic
renal cell carcinoma, are always welcome. But what concerns
me is that once again FDA has approved a new drug without
demanding any proof that it actually enhances the clinical
outcome for patients. According to an astonishingly candid
admission on the FDA's own Web site, "At this time, it
is not known whether Sutent will improve symptoms, or help
patients with this disease live longer." Yet, defying
logic, the agency went ahead and approved it anyway.
The FDA Web site also has a rather more complete picture
of Sutent's possible adverse effects than some of the rather
sketchy meeting abstracts. Side effects include:
- A heart problem called left ventricular dysfunction, which
can lead to congestive heart failure
- Stomach and digestive system problems including diarrhea,
nausea, mouth sores, indigestion and vomiting
- Adrenal gland insufficiency
- Skin and hair changes: Sutent may cause the skin to turn
yellow and hair to lose color
- Swelling
- Mouth pain and irritation
- Taste changes
- Harm to an unborn baby, if the drug is used in pregnant
female patients
All of this is a far cry from the way that such 'targeted'
therapies were introduced to the world a decade ago, when
the first such drugs, Herceptin, Rituxan and Gleevec, were
hailed as non-toxic magic bullets for cancer. I have kept
many of the old magazine cover stories from those days and
they make for sobering reading today. The fact that these
targeted drugs have so far failed to live up to their billing
does not seem to have diminished the hype surrounding them.
When Pfizer submitted its approval application for Sutent
to the FDA last fall, FDA chairman Henry "Hank"
McKinnell said: "We're seeing enormous excitement in
oncology circles, which is a good leading indicator of the
importance of this revolutionary new medicine."
This kind of effusive endorsement creates an echo chamber
effect: big drug companies hire compliant doctors as well-paid
advisors, who then make excited noises to energize the rank-and-file
of oncologists and influential patient representatives. This
in turn sways the mainstream media, which are always hungry
for feel-good stories about the supposed steady progress in
the war against cancer. The media influence the broad public,
creating a celebratory atmosphere about these drugs in the
general culture, and (not accidentally) raising patient demand
for the drugs - which in turn has a significant effect on
physicians' prescribing habits.
Pfizer's second quarter 2006 sales for Sutent were just $36
million. But watch what happens. With European approval, and
with increasing "buzz" among oncologists here and
abroad, Sutent sales are expected to skyrocket. Pfizer has
said that Sutent may earn $1.5 billion in annual sales by
the year 2010, according to Bloomberg News (Moore
2006). Not bad for a drug that still hasn't been proven to
enable patients to live a single day longer.
--Ralph W. Moss, Ph.D.
References:
Moore, Duncan. U.S. Drug
Sales Increase 5.4% In 2005, Expected To Rise At That Rate
Until 2010, Report Says. Philadelpia Enquirer, Feb.
23, 2006. Available at:
http://www.philly.com/mld/philly/business/13937730.htm
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IMPORTANT DISCLAIMER
The news and other items in this newsletter
are intended for informational purposes only. Nothing in this
newsletter is intended to be a substitute for professional
medical advice.
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