Lopinavir (with the trade name of
Kaletra) belongs in a class of anti-HIV drugs called protease
inhibitors. Protease inhibitors work by blocking, or inhibiting a part of
HIV called protease. When protease is blocked, copies HIV makes of itself
are are unable to infect new cells.
Kaletra is now approved for prescription.
Kaletra is the sixth protease inhibitor to be approved for the
treatment of HIV infection.
Taking the drug: The standard dose of
Kaletra is three pills taken twice a day with food. Each Kaletra pill
contains 133mg of
Kaletra and 33mg of the protease inhibitor Norvir (ritonavir). If
you're taking
Kaletra at the recommended dose, it's important to know that
you'll also be taking a total of 200mg of Norvir each day. If you're
allergic to Norvir it may not be possible for you to take
Kaletra - check with your doctor.
Kaletra is also available in a liquid form for children.
Trial results:
Kaletra has shown a strong anti-HIV effect in clinical trials. One
study investigated different doses of
Kaletra taken with d4T (Zerit) and 3TC (Epivir). No one in this
study had taken anti-HIV drugs before. After 72 weeks (nearly a year and a
half) of treatment, 80% of the 51 people taking the approved dose of Kaletra
had viral load levels less than 400 copies. T-cells increased by an average
of 256 cells. About 4% (1 in 25) of the participants dropped out of the
study because of side effects.
One reason a doctor might prescribe
Kaletra is because of its strength and because it seems to work for
people whose HIV has become resistant to other protease inhibitors.
Kaletra may be able to work for people whose HIV is resitant to the
other approved combinations of anti-HIV drugs. Up until
now, when someone has taken a lot of different anti-HIV drugs that have
stopped working, it has been complicated to figure out what regimen to take
next. Because of its strength, and
including Norvir which some people find difficult to take, the side effects
of
Kaletra may be stronger as well.
A large, ongoing study is comparing Kaletra taken with d4T and 3TC to the
combination of the protease inhibitor Viracept (nelfinavir) taken with d4T
and 3TC. The study involves 653 people that have never taken HIV drugs
before. After six months of treatment results are similar for both
combinations. In the
Kaletra/d4T/3TC group, 79% of the participants have viral loads less
than 400 copies. In the Viracept/d4T/3TC group, 70% of the participants have
viral loads less than 400 copies. T-cell counts in both groups increased by
an average of around 150 cells.
Side effects: Kaletra side effects can include diarrhea,
significant increases in blood fats (cholesterol and triglycerides), liver
toxicity (with increased liver enzymes), stomach pain, feeling weak or
tired, headache, nausea and vomiting. Increases in cholesterol and
triglycerides were also reported in up to a quarter of study participants.
In some cases increases in cholesterol and triglycerides were very large,
and regular monitoring of these blood fats is very important for anyone
taking Kaletra.Diarrhea was reported by about a
quarter of participants in Kaletra studies. People co-infected with hepatitis B and/or C may be at
greater risk of developing liver toxicity from Kaletra.
Kaletra may also be linked to a side effect called pancreatitis.
Pancreatitis is a potentially dangerous inflammation of an organ called the
pancreas. It is not yet certain if
Kaletra causes pancreatitis. All cases have involved people taking other
drugs. Researchers are now studying whether
Kaletra played a role in the cases of pancreatitis. The manufacturer
recommends monitoring triglycerides and amylase in people taking
Kaletra to watch for signs of pancreatitis. Currently this side effect has been seen in less than 1% (1 out of
100) people taking
Kaletra.
Combining
Kaletra with other anti-HIV drugs: There are no serious interactions
between
Kaletra and NRTI anti-HIV drugs. However, it's recommended that the NRTI
drug ddI (Videx) be taken one hour before or two hours after
Kaletra. The NNRTI drug delavirdine (Rescriptor) has
not been studied with
Kaletra. Based on what is already known about the drugs, it is likely
that Rescriptor will increase Kaletra levels. The NNRTI anti-HIV drugs efavirenz (Sustiva) and nevirapine
(Viramune) lower Kaletra levels in the body. When taking Sustiva or Viramune
with
Kaletra it is recommended the Kaletra dose be increased to 4 pills
twice-daily (total of 8 pills).
Drug interactions: The following drugs should NOT be taken with
Kaletra: astemizole (trade name Hismanal), cisapride (Propulsid),
flecainide (Tambocor), midazolam (Versed), propafenone (Rythmol), pimozide (Orap),
terfenadine (Seldane), triazolam (Halcion) and a class of migraine drugs
called ergot derivatives. Taking the fat-lowering drugs lovastatin (Mevacor) or simvastatin (Zocor) with
Kaletra is not recommended.
Kaletra may increase the levels of other fat-lowering drugs such as
atorvastatin (Lipitor), potentially increasing the chances of side effects.
Kaletra increases levels of the antibiotic rifabutin (Mycobutin)
making a 75% reduction of the normal rifabutin dose necessary.
Kaletra decreases the levels of methadone in the body and methadone
doses may need to be increased if these drugs are used together. The herbal
supplement St. John's Wort should not be taken as it is likely to
significantly decrease Kaletra levels. Great care should also be taken about
using Viagra. Kaletra is likely to greatly increase levels of Viagra in the
body which could lead to serious side effects. The TB drug rifampin should be
avoided as it also reduces
Kaletra levels. Other potential drug interactions are listed in the
label that comes with
Kaletra which can be downloaded from the Internet at
www.Kaletra.com.
The manufacturer of
Kaletra has set up a patient assistance program for people having
trouble accessing or affording the drug. Call (800) 659-9050 for more
information.
