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You may have heard the expression
“knowledge is power.”
Well, today we're going to give you more power
to control your diet and lifestyle
by giving you the facts.
Welcome to the Nutrition Facts Podcast.
I'm your host, Dr. Michael Greger.
Did you know that most chemotherapy drugs
are approved by the FDA without evidence of benefit
on survival or quality of life? Here's our first story.
Over the next few decades, the number of new cancer cases
will continue to skyrocket. Are we winning the war on cancer?
Sadly, in general, no,
this despite the introduction of hundreds of new anticancer drugs.
The war on cancer has been likened to the war on terror.
No matter how many drone strikes you do, it's nearly impossible
to kill all the bad guys, and no matter how precise the bombing,
one must always consider the collateral damage.
The toxicity from cancer therapy can be debilitating,
and not just health-wise. There's also the "financial toxicity."
Patented anticancer drugs are priced at up to
nearly a thousand dollars a day.
Even with health insurance, the average cost to patients
for stage IV breast cancer, for example, can run $190,000.
It's bad enough to be fighting for your life without bankrupting
your family at the same time – a problem still common to this day.
Who can forget the apocryphal story of Walter White, working two jobs
with health insurance and still could not afford the cancer care?
Now, not everyone is willing to start their own meth lab,
but many are willing to go for broke.
A large proportion of cancer patients reported their willingness
to declare bankruptcy or sell their homes to pay for treatment.
I mean, look, aren't the high prices justified if new and innovative
treatments offer significant benefits to patients?
But you may be shocked to find out that many
FDA-approved cancer drugs may lack clinical benefit.
Well, then how did they become FDA-approved?
Most approvals of cancer drugs are based on flimsy
or untested surrogate endpoints,
and postmarketing studies rarely validate the efficacy and safety
of these drugs on patient centered endpoints.
Let me explain what that means.
New chemo drugs are increasingly approved just based on
so-called surrogate endpoints, which means instead of looking at what
we really care about — survival or quality of life — they approve
drugs based on things like response rate, tumor shrinkage.
But who cares if a tumor shrinks if it doesn't actually extend
your quantity or quality of life?
It's kind of counterintuitive, but just seeing a tumor shrink
on a CT scan or MRI is not necessarily correlated
with improvements in survival or symptoms.
In fact, most studies that have actually followed people out
found low correlations with survival.
The most recent comprehensive analysis found 90% of studies
of such validation trials found little correlation with overall survival.
Of 36 new chemo drugs approved by the FDA based on these kind
of surrogate endpoints, once they were actually
put to the test in the real world,
only 1 in 7 was actually shown to extend life,
and half explicitly flopped,
and the rest remain untested, revealing that most cancer drug
approvals have not been shown to, or do not, improve
clinically relevant endpoints.
Exorbitant drug prices are bad enough for treatments that work,
but charging vulnerable patients for drugs without evidence that
they actually improve patients survival and quality of life
is unconscionable.
Why doesn't the FDA require proof that chemo drugs
actually benefit patients before approving them?
Drug companies say that requiring randomized, controlled trials
with meaningful measures would take too long,
but the study time reduction using surrogate endpoints
rather than overall survival is estimated at just 11 months.
So instead of it taking 7.3 years to come to market on average,
it would take 8.2 years.
Yes, look, we want to get these drugs out as soon as possible,
but only if they're actually going to help people.
Do cancer drugs improve survival or quality of life?
You don't need to know, according to our broken regulatory system.
And things aren't much better over in Europe.
A systematic evaluation of chemo drug approvals showed
that most entered the market without evidence of benefit
on survival or quality of life.
And even years later, there was still no conclusive evidence
that these drugs offered any benefit, and when they did,
the gains were often marginal.
That's why you see editorials in the Journal of the
National Cancer Institute referencing Hans Christian Andersen,
the author of the tale of "The Emperor's New Clothes."
The studies all converge on a singular conclusion:
only a minority of new cancer drugs approved by US and European
regulatory authorities in recent years deliver clinically meaningful benefits
to patients. In fact, some cancer- related deaths may be hastened,
or even caused, by the toxic effects of chemotherapy
rather than the cancer itself.
Based on a review of tens of thousands of cancer patients, in as many as 27%
of cases the cancer treatment itself caused or hastened death.
Okay, but it might be worth that risk if the potential benefit
is large enough. And that's the subject of my next video,
"How Much Does Chemotherapy Improve Survival?"
Though we often hear new cancer drugs described as game-changing
breakthroughs, most afford much more modest benefits.
In my last video, I quoted a recent editorial in the
Journal of the National Cancer Institute suggesting that the majority
of new cancer drugs don't deliver clinically meaningful benefits at all.
At least when they are later proven to be ineffective,
they're pulled from the market, right?
No! Even when postmarket studies show the new drugs to have
no clinically meaningful benefit compared to not just older drugs
but compared to nothing, compared to a sugar pill,
most chemo drugs retain FDA approval and remain on the market,
even at the same ridiculous prices. In fact, the most expensive drug
they looked at, the one costing $169,836 a year,
did not improve overall survival at all, and actually worsened quality of life.
$169,000 just to make you feel worse with no benefit.
Why pay a penny for a treatment that doesn't actually help?
And even when they do improve survival,
what does that actually mean?
Currently, the trend is for Big Pharma to design large trials that may detect
statistically significant, but often trivial,
differences in survival endpoints.
For example, check out this famous trial.
Adding this second drug, erlotinib, to gemcitabine for advanced
pancreatic cancer significantly prolonged overall survival.
Yeah, they suffered more side- effects, but we're not just talking
about tumor shrinkage. They lived significantly longer.
The placebo group only lived 5.91 months, whereas
the added drug group survived all the way to 6.24 months?
Wait a second. They only lived a third of a month longer?
That's just 10 days.
All the side-effects and expense for an average of just 10 days?
That's why doctors shouldn't use the statistical jargon ---
significant improvement in survival ---
while informing patients about benefits of new treatment.
When patients hear the word "survival,"
they're not thinking about a week and a half. If you put
all the new chemo drugs together approved over the last dozen years,
the average overall survival benefit is 2.1 months.
Now look, two months is two months, I don't want to downplay that, but
time and again, surveys have indicated that patients expect much more.
Incredibly, about three-quarters of patients with metastatic lung
or colorectal cancer did not report understanding
that their chemo was not at all likely to cure their cancer.
I mean, that's the primary treatment, but the chemo's not curative;
it's just eking out a few extra weeks or months.
Why weren't the majority of patients told that?
It's not that they were being over-optimistic,
explained the researcher. They were under the mistaken belief
that the treatment offered a chance of cure when it in fact didn't.
That deprives patients of the opportunity
to weigh the risks and benefits and make their own decisions
about their own body.
If you ask cancer patients, most want at least half a year
to stomach the side-effects, which suggests that most
cancer patients might not choose chemotherapy
if they knew how little they'd actually benefit.
But look, everyone's different. One patient they interviewed
said living even one week longer would be worth it;
whereas another said they wouldn't even want to do chemo
for two extra years of life; they wouldn't want
anything to interfere with the quality of the time they had left.
Either way, people deserve to know the truth.
I find it telling that oncologists and cancer nurses themselves
express less willingness to accept intensive chemotherapy,
given the associated toxicities.
Most chemo drugs are cytotoxic, meaning they work by killing off
cancer cells, but they also kill off some healthy cells
as collateral damage, which is why they can damage
our nerves, cause irreversible heart failure,
slough off the linings of our gut, or damage your immune system.
Drug companies frequently downplay the risks, though, for example,
describing this breast cancer drug as having acceptable side-effect
profiles for most patients, or this pancreatic cancer drug as having
a manageable and mostly reversible safety profile.
These were studies published in top medical journals.
Naturally, readers would take these statements to be true.
However, if you actually look at the data,
the number of serious, even life- threatening side effects was double,
or even five times higher on the new breast cancer drug.
And the manageable and mostly reversible side-effects
evidently weren't referring to those who were killed by the drug.
I like how they even included like a cheat sheet.
Acceptable toxicity. Acceptable to whom?
Manageable? Serious events and deaths can never
be considered manageable.
And feasible? Who would sign up for a drug whose toxicity
could only be described as feasible?
Favorable? Compared to what?
Tolerable? That's for the patient to decide.
And any drug that kills people can hardly be considered safe.
Still, patients may very well consider it worth the risk.
For some cancers, we've made tremendous strides.
Testicular cancer, for example.
There is greater than a one in three chance that chemotherapy
could enable you to survive at least to the five-year mark.
The same with Hodgkin's disease, a relatively rare form of lymphoma.
But even when researchers tried to err on the side
of over-estimating the benefit, for most common cancers —
colon, lung, breast, and prostate —
the chances appear to me more like 1 or 2 percent.
We would love it if you could share with us your stories
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Go to nutritionfacts.org/testimonials.
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To see any graphs, charts, graphics, images, or studies mentioned here,
please go to the Nutrition Facts Podcast landing page.
There you'll find all the detailed information you need –
plus, links to all of the sources we cite for each of these topics.
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