Boceprevir
and telaprevir are currently only approved for hepatitis C-mono-infected people
by the EU and US licensing agencies. But in the UK, NICE (the body producing
clinical standards in health and social care) recently gave a favourable
opinion on boceprevir and telaprevir-based triple therapy with interferon and
ribavirin.5
“This
‘approval’ includes co-infected patients,” says Dr Sanjay Bhagani of London’s Royal
Free Hospital,
“though whether commissioners will pay for this or not is a different matter.”
These new
drugs are not cheap. The ‘list prices’ (the ones the NHS ends up paying are
likely to be lower) are £30,800 for a 44-week course of boceprevir and £22,398
for a 12-week course of telaprevir – and, on top of that, you have to add in
£11,000 for the interferon and ribavirin.
At this
stage, your best chance of receiving these new drugs is through being part of a
clinical trial, as the drug company has to pay for the cost of these. “There is
no access to the new hepatitis C treatments for co-infected patients on a
routine basis,” says Dr Mark Nelson of London’s Chelsea and Westminster
Hospital. “But you can
get the drugs from major centres like us and the Royal Free, who will be doing
the clinical trials people need to join."
Whether you
should try the new drugs depends primarily on whether you have progressive
liver disease. Just as HIV treatment has been based on worsening immune
deficiency, hepatitis C treatment should be based on worsening liver fibrosis.
Not everyone
with hepatitis C will need treatment. Only a quarter of hepatitis
C-mono-infected people develop serious liver disease, and this typically takes
10 to 40 years, often with no symptoms until advanced stages. For co-infected
people without an urgent need for hepatitis C treatment, there’s probably time
to wait.
Even if the
approved drugs were more readily available, Mark Nelson comments, they're like
the first-generation HIV protease inhibitors.
"Telaprevir
and boceprevir are relatively difficult to take and relatively toxic compared
to the second generation. If you have minimal liver disease, probably the best
option is to wait."
Daniel Fierer
from Mount Sinai Hospital
in New York
adds that boceprevir and telaprevir are "unpleasant, onerous drugs...
Think AZT if we're lucky or, if we're unlucky, ddC... If you don't need it,
don't take it." He’s even more pessimistic when it comes to re-treatment.
"If patients have failed treatment a number of times, their chances of
cure with the new drugs are pitiful," he said. "Taking treatment now
may prevent you from getting into a clinical trial further down the line, and
you may develop resistance."
Other
patients, however, do not have the luxury of time. The risk of progression to
liver damage is higher and it happens faster in co-infected people; successful
treatment can slow, halt or even reverse it. Doctors do not want to give
treatment to people who never would have progressed to liver damage without it,
but are also concerned not to delay too long because once people get to the
stage of cirrhosis, treatment becomes more difficult and less effective.
"If
people need to be treated, they need to be treated now," said Dieterich.
"If they have significant liver disease, I think it's definitely indicated
to go ahead. If you need to take pegylated interferon and ribavirin with all
their side-effects, you want to optimise your chance of success."
At a CROI
symposium on treating HIV/hepatitis C co-infected patients, Jürgen Rockstroh
from the University
of Bonn proposed an
algorithm for deciding when to consider therapy:
- People
with no or minimal fibrosis (stage F0-F1) may defer treatment and wait for
better therapies.
- People
with moderate to advanced liver disease (stages F2-F3) have the biggest
risk of progression that could be controlled with treatment now.
- People
with cirrhosis (stage F4) have the highest need, but also the lowest
response rate and greatest risk of complications, and should only be
treated in specialised centres.
It is not as
easy to predict who will experience liver disease progression, or even to tell
if it is occurring, as it is to measure CD4 cells. Liver biopsy remains the
gold standard for staging liver damage, but it is too invasive and expensive to
repeat often. Fibroscan (which uses
sound waves to measure liver stiffness) and various blood biomarkers are widely
used, but they may not be able to distinguish between intermediate stages where
decision-making is most critical.
"It's a
balancing act," Rockstroh concluded. "How much progression will
happen in one, two, or three years, versus the window of development of new
therapies?"