Last week's (April 12th) blog post was
an overview of the highly idiosyncratic nature of the pharmaceutical
marketplace and the pricing of pharmaceuticals. Today's The New York
Times carried a front page story by Andrew Pollack, The New York
Times biotechnology industry reporter, about how doctors
may increasingly be influenced by treatment costs when advising
patients.1
Interestingly, while the focus of the article is on the general
impact of health care costs on physicians' decision-making, other than
a passing mention of MRIs, the only other examples of cost are drawn
from the world of pharmaceuticals-- Avastin vs. Lucentis for macular
degeneration, Aloxi for chemotherapy-related vomiting and, everyone's
favorite target of late, Solvadi for Hepatitis C. Pollack's article
also discusses the decision by some physician groups, such as the
American Cardiology Society (ACS), to rate the value (that is economic
value) of treatments in their joint clinical practice guidelines and
performance standards. The article notes that the ACS committee that wrote the new policy recommended using QALYs (quality
adjusted life years, a widely used standard in health economics) as a
principal metric in measuring a treatment's cost effectiveness. So,
given the continuing public attention to pharmaceutical prices, this
week I will briefly discuss pharmacoeconomics, which should have, but
only in some cases does have, an effect on pharmaceutical prices.
First, QALYs, as mentioned in
Pollack's article, attempt to provide a measure of two variables in a
single unit: the first is the effect of a treatment on the actual
duration of life, while the second is the quality of life provided by
the treatment. This can become technical and complicated, and those
who wish a more detailed introduction to QALYs might want to start
with an article by Luis Prieto and Jose Sacristan, Problems
and solutions in calculating quality-adjusted life years (QALYs).2
However,
for this discussion, a relatively basic understanding of QALYs should
be sufficient. For example, a
treatment that resulted in the five-year survival of end-stage cancer
patients, but only in a coma, would not be providing a significant
benefit in terms of quality-adjusted life years. A treatment that
extended the survival of end-stage cancer patients in reasonably good
health for six months might provide .5 quality adjusted life years.
If the purpose of assigning a value in QALYs is simply to compare the
benefits of two treatments by converting both to a common
denominator, then it isn't necessary to worry about how much a QALY
is worth in monetary terms. A treatment that results in an increase
of 2 QALYs is presumed to be better than a treatment that results in
an increase of 1.5 QALYs.3
Of course, if QALYs are going to be used in an economic analysis,
then a value in dollars and cents needs to be assigned to a QALY, and
the Pollack article states that the cardiologists would consider
treatments that increased the average outcome for patients by a full
QALY at a cost of $50,000 to be "high value" while
treatments costing $150,000 or more per additional QALY would be
considered "low value."
So QALYs are a unit by which the
effect of different drugs or other treatments can be measured on a
common scale. It is a useful tool for pharmaceoeconomics.
Pharmacoeconomics is the study of the economic value or impact of a
pharmaceutical. Sometimes pharmacoeconomic analysis requires
incorporating a unit such as QALYs, but in many cases QALYs are
really not essential to an economic evaluation of a drug's benefits
and risks. For example, from a health insurance company's
perspective, a drug which costs $84,000 (like Solvadi) must be
considered in light of the health care costs of persistent Hepatitis
C infection, as well as the cost of alternative treatments that only prevent a percentage of patients from progressing to later
stages of liver disease. The average annual costs of treating
patients with Hepatitis C are estimated to be approximately $24,176,4
costs which can continue for a significant number of years for the
average patient. For a health insurance company, Solvadi may well
produce a net savings in expenses, without the need to use QALYs in
the calculation. Of course, Gilead knew that
when they set the price of Solvadi. A treatment may be expensive in
absolute terms, but if it actually reduces overall healthcare costs,
it is worthwhile in pharmacoeconomic terms and will be worthwhile for
insurance companies to cover.
In one of the other examples
highlighted in Pollack's article, the relative cost of Avastin and
Lucentis raises a somewhat more complicated pharmacoeconomic issue,
as well as a terrific example of the way that pharmaceutical prices
are determined. Both drugs were developed and marketed by
Genentech. Both drugs work by targeting the vascular endothelial
growth factor, which is a key part of the pathway for blood vessel
growth. In many cancers that take the form of solid tumors, such as
colorectal cancer, stopping or greatly reducing the growth of new blood vessels stops or slows the growth of the tumors. In
"wet" age-related macular degeneration (AMD), the abnormal
proliferation of capillaries (small blood vessels) to the retina
causes increasing damage to the retina and vision loss and blocking VEGF slows down capillary growth and vision loss. Avastin, an
antibody that binds to VEGF, was developed to treat colorectal
cancer and was approved in 2004. Lucentis, the antigen-binding
fragment of an antibody that binds to VEGF, was approved for the
treatment of macular degeneration in 2006 and costs just under $2,000 a
dose. Avastin, when used to treat colorectal cancer is priced at
$50,000 to $100,000 per patient per year, but the cancer dose is many
times greater than the dose injected into the eye to treat macular
degeneration. A pharmacist can provide many doses
for AMD from the amount used for a cancer treatment, and charge about
$50 per dose. It should go without saying that Genentech would
rather not have doctors using Avastin to treat their macular
degeneration patients instead of Lucentis. It should also be obvious
that the price of Lucentis has nothing whatsoever to do with the cost
of producing that amount of drug, as it is unlikely that it is
significantly different from the cost of producing Avastin.
So, if Avastin costs $50 and Lucentis
costs $2000, what is complicated about the pharmacoeconomics? First,
the effectiveness of both drugs is equal, so in terms of
effectiveness the pharmacoeconomic choice is overwhelmingly Avastin.
But the safety of the two drugs may not be equal- there is a
potentially greater risk of adverse effects with the use of Avastin
than with Lucentis, according to a review article by Pasquale
Ventrice and others.5
It appears to be a small increase in risk and does not include any
increased risk of death. A large review of 145,000 Medicare patients
treated for macular degeneration found NO difference in heart attacks
or death and no statistically significant increase in bleeding or
stroke.6
However, the cost of treating a patient monthly (as it was approved
and labeled) would be about $23,400 for Lucentis, while Avastin
monthly treatment would cost only $600, a difference of almost $23,000
per patient per year. Treating 1,000 patients with Avastin instead of
Lucentis would save about $23 million. So if there were one additional
serious adverse event per 1,000 patients treated with Avastin instead
of Lucentis,7
we would have to assign a cost of $23 million to that event in order
to offset the basic difference in price. It is clear that the risk
of additional non-fatal systemic adverse events with Avastin instead
of Lucentis is extremely unlikely to justify the cost difference.
It
is completely understandable why Genentech undertook to develop a
different anti-VEGF agent for macular degeneration, rather than
entering clinical trials with Avastin. Using an antibody fragment
rather than the whole antibody might have had clinical significance,
although it turned out not to be the case. But more importantly,
from the Company's perspective, it was an effort to keep from competing
with their own product at a very low cost. Why do they charge about 40 times more for a dose of Lucentis for AMD as the cost of a dose of Avastin prepared for AMD? Because they hope they can. However, the
pharmacoeconomics says it absolutely is not worth it. In a future
post, I will look at how drug marketing succeeds in the face of such
evidence.
1Andrew
Pollack, Treatment
Could
Influence
Doctors'
Advice, New York Times, April 18, 1014 at A1 (also available online
at
http://www.nytimes.com/2014/04/18/business/treatment-cost-could-influence-doctors-advice.html?hp&_r=0)
2Published
in Health
Qual Life Outcomes,
in 2003
and available online at
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC317370/
(visited April 18, 2014).
3Of
course, QALYs used even in this way are based on assumptions about
general preferences, whereas an individual's preferences may differ.
A particular patient might prefer 3 years of being alive, alert,
and bedridden to 2 years of being alive, alert, and able to go about
the activities of daily life, though the latter outcome would likely
be assigned a greater value in QALYs.
4
Maria
Seyrig, The
Economic Cost of Advanced Liver Disease,
Henry Ford Health Systems, November 7th, 2011, online at
http://www.henryford.com/body.cfm?id=46335&action=detail&ref=1465.
5
Pasquale Ventrice, et al, Anti-Vascular Endothelial Growth
Factor Drugs Safety And Efficacy In Opthalmic Diseases, J
Pharmacol Pharmacother. Dec 2013; 4(Suppl1): S38–S42,
online at
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3853666/?report=printable
6 Curtis
LH,
Hammill
BG,
Schulman
KA,
Cousins
SW,
Risks
of mortality, myocardial infarction, bleeding, and stroke associated
with therapies for age-related macular degeneration,
128(10) Arch.
Ophthalmol.
1273-9
(October 2010), abstract at
http://www.ncbi.nlm.nih.gov/pubmed/20937996.
7For
yet another look at the risks, albeit another inconclusive look, see
the CATT group study in the May 19, 2011 New England Journal of
Medicine, Ranibizumab and Bevacizumab for Neovascular Age- Related
Macular Degeneration (364:20) NEJM 1897).
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