Being Alive 1997 Apr 5: 4
What are Protease Inhibitors?
Protease inhibitors are a new type of antiretroviral (drugs
that stop the reproduction of hiv in your body). Protease drugs
work by blocking a part of hiv called protease. Without
protease, 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 antiviral drugs (AZT, ddI, ddC, d4T, 3TC), can lower
viral load (the amount of hiv in your blood) and raise T-cells
(CD4 cells). The greatest effect was seen in people taking
combination therapy. However, it's important to remember that
more studies are needed to better understand how to use these
When Should I Start Taking Protease Inhibitors?
No one knows yet the best time to begin taking protease
inhibitors. One study of people with aids who have low T-cells
(100 or lower) showed that those who took a protease inhibitor
lived longer (by approximately six months) than those who did
not take a protease inhibitor. 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 protease
Doctors do not yet know whether 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 drug when viral load is low could allow the
drug to be more effective.
Can Drug Resistance Occur with Protease Inhibitors?
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. Resistance does not go
away. Also, developing resistance to one protease drug will
often mean that you are resistant to other protease drugs as
well. This is called cross-resistance.
Some studies show that taking protease inhibitors in
combination with other anti-hiv drugs may greatly reduce the
chance of developing resistance. But the best way, at this
time, to avoid or delay the development of drug resistance is
to make sure you take the drugs properly. Skipping doses,
taking lower than prescribed doses, not following food
guidelines, and not taking the drugs on schedule, all encourage
the development of 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
feel you really need the drugs or are better prepared to take
the drugs properly.
The standard dosage is two 400 mg capsules taken every eight
hours (3 times a day-e.g., 8 am, 4 pm, 12 midnight). Crixivan
must be taken on an empty stomach or, if necessary, with a
light, low-protein, low-fat meal (e.g., corn flakes, skim milk,
apple juice, dry toast, coffee or tea; do not take with
grapefruit juice). Take each dose with a large glass of water
and drink at least six more large glasses of liquid throughout
In studies, the greatest effect was seen with Crixivan in
combination with AZT/3TC. Other combinations may also be useful
but have not been tested yet. In deciding which combination to
take, think about possible side effects and, if possible, look
for a combination that you have not taken before.
Storage and Cost
Keeping capsules dry in their bottle is very important. To do
this, put the small cloth package or cotton that comes in the
bottle back after every use.
Crixivan sells for about $6,000 a year. Most Medicaid programs
and private insurers cover it. Crixivan is covered by the ADAP
program in California. Merck, the company that makes Crixivan,
runs a patient-assistance program that will supply the drug at
no cost if you meet certain qualifications. Call 1.800.927.8888
Monday-Friday, 9 am-8 pm, for more information regarding
Nephrolithiasis (defined as pain in the sides, blood in urine
or kidney stones) occurred in 4% of people in clinical studies.
Drinking at least eight large glasses of water throughout the
day can help prevent nephrolithiasis. Other side effects
include nausea, abdominal pain, headache, weakness/fatigue,
diarrhea, taste changes and back pain. Less than 2% of patients
reported having these side effects in clinical studies.
Most drugs can be taken with Crixivan. Rifabutin and
ketoconazole (Nizoral) will require a change in the amount of
Rifampin, terfinadine (Seldane), astemizole (Hismanal),
cisapride (Propulsid), triazolam (Halcion) and midazolam
(Versed) should not be taken with Crixivan.
Speak to your doctor about other possible drug interactions.
This information is reprinted from a GMHC Fact Sheet. For other
Fact Sheets or more information contact Gay Men's Health
Crisis, 129 W. 20th St., New York, NY 10011 or call