Protease Inhibitor: Invirase (Saquinavir)

PROTEASE INHIBITOR:
INVIRASE (SAQUINAVIR)

What are Protease Inhibitors?
P rotease inhibitors are a new type of antiretroviral (a drug
that stops the reproduction of HIV in your body).
Protease drugs work by blocking a part of HIV called
protease. With protease blocked, HIV makes copies of virus
that can't infect new cells. Studies (clinical trials) of
protease inhibitors have shown that these drugs, taken alone
or in combination with other antiretroviral drugs (AZT, ddl,
ddC, d4T, 3TC ), can lower viral load (the amount of HIV in
your blood) and raise T-cells (CD4 cells). The greatest effect
has been seen in people taking combination therapy.
However, it's important to remember that more studies are
needed to better understand how to use these drugs.
When Should I Start Taking Protease Inhibitors?
No one knows exactly when is the best time to begin
taking protease inhibitors. Several studies of people who
have low T-cells (100 or lower) have found that those who
add a protease inhibitor along to other HIV medicine get
about half as sick as those who do not. Based on these
results, if you have: 1) low T-cells, 2) high viral load, 3)
symptoms of illness, and/or 4) have had HIV disease for a
long time, you may want to talk with your doctor about
starting a combination that inclues a protease inhibitor.
Doctors have not yet confirmed that taking these drugs
early in HIV disease-when T-cells are high and viral load
is low-will help prolong life or prevent the development
of AIDS. In theory, starting a protease inhibitor when viral
load is low will allow the drug to be more effective.
Can Drug Resistance Occur with
Protease Inhibitors?
Yes. HIV eventually learns to work around the effect of
the drug. This is called drug resistance. Resistance
causes the drug to work less well or not to work at all.
Resistant HIV may not go away, even if you stop taking the
drug. Also, developing HIV that has resistance to one antiprotease drug will often mean that the HIV is resistant to
other such drugs as well. This is called cross-resistance.
Some studies show that taking protease inhibitors in
combination with other anti-HIV drugs may greafly reduce
the chance of developing resistance by further controlling
the virus. To avoid or delay the development of drug
food guidelines and not taking the drugs on schedule
weakens the drugs' effect. HIV can then reproduce more.
The more HIV reproduces, the better its chance to develop

drug resistance. If you think that you are not able to follow
the treatment routine which you and your doctor have put
together, then you might want to wait until you are better
prepared to take the drugs properly.

Invirase (also called saquinavir):
Dose
Three 200 mg capsules taken three times a day within
two hours after eating a full meal, preferably high in
fat. Invirase must be taken on a full stomach to be
effective. Some healthier foods that are high in fat
include: lean red meat, peanut butter, avocado, cheese,
bread with butter, whole or 2 percent milk products.
Unlike other protease inhibitors, Invirase has been
shown to be effective only when used in combination with
other anti-viral drugs, including AZT, ddC or AZT/ddC.
Talk with your doctor about which combination and which
doses are best for you.
Clinical studies have shown that Invirase is not as
potent as other protease inhibitors in lowering the level of
virus in the blood. This is mostly due to the fact that
Invirase is poorly absorbed into the blood. A new,
improved version of Invirase (the soft gel capsule) will be
available in late 1997 that will increase the levels of
Invirase in the blood eight or nine times.
Another way to increase the level of Invirase in the
blood is to take it in combination with the Abbott protease
inhibitor, Norvir. Norvir greatly reduces the breakdown of
Invirase by the liver. Studies have found that this
combination is highly effective against HIV. Other trials are
now looking at combining the new version of Invirase with
either Norvir or Viracept, a protease inhibitor with an effect
on the liver that is somewhat weaker than Norvir's.
Storage
Keep capsules in their bottle at room temperature.
Side Effects
Invirase has fewer side effects than other the other protease
drugs. Side effects might include diarrhea, stomach upset,
and nausea. However, most people in the clinical studies
did not develop these problems.
Cost
Invirase sells for about $7,800.00 a year. Most Medicaid
programs and private insurers reimburse the cost of the
drug. The ADAP programs in New York and many other
states also pay for Invirase. Hoffman-La Roche, the
maker of Invirase, has a patient assistance program for
people who are not covered by insurance and who cannot
furthe informaion, cl
1-800-282-7780.JEt4II ~7 'L I7

I

Availability
Invirase is an approved
drug and is available
through any pharmacy.

Inirseshud IOTbetae
wih ifam in r.1fbti (y 91ti
terfnadie (eldae), ste izo
9* aalpenbi talpheny in
(Dln in),dexm.hasI.9eadrn

For other Fact Sheets or for more information, contact GMHC, Department of Treatment Education and Advocacy, 119 West 24th Street, New York, NY 10011 [phone]