Kaletra – brand name

lopinavir/ritonavir – generic name

Kaletra belongs to a class of HIV drugs called protease inhibitors (PIs).

The PIs block protease, a protein that HIV needs to make more copies of itself. This may slow down HIV disease.

The Food and Drug Administration (FDA) has approved Kaletra for use in combination with other HIV drugs for the treatment of HIV infection in adults and children over six months old. 

Kaletra comes in:

• Film-coated tablets that contain 200 milligrams (mg) lopinavir and 50 mg ritonavir
• Liquid

(The original formulation of Kaletra was a soft-gel capsule. This formulation is being discontinued in March 2006. The capsule is being replaced by the tablet because the tablet does not require refrigeration, has no food restrictions, and requires fewer pills per dose.)

Kaletra can be taken once or twice a day:

Once a day

• The standard dose is four tablets of Kaletra once a day.
• This option is only approved for HIV+ people who are starting therapy for the first time.

Twice a day

• The standard dose is two tablets of Kaletra twice a day.
• This option is approved for HIV+ people who have taken other HIV medications in the past.

There are no food restrictions with Kaletra tablets.

Check with your child’s doctor for children’s dosing.

Kaletra must be used with other HIV medications to treat HIV.

Tell your doctor if you have liver problems, diabetes, or hemophilia.

As with all HIV drugs, it is important to take Kaletra as prescribed. Missing or skipping doses can cause your blood levels of the drug to fall too low and resistance can develop. When your virus becomes resistant to an HIV medication, that drug may stop working.

Kaletra can be used both for HIV+ people being treated for the first time and for those who are switching from other drugs that no longer work.

Kaletra may be a good “salvage therapy” option because it reaches high levels in the blood and works well against HIV that has developed resistance to other protease inhibitors.

Your doctor can run a resistance test to help determine whether Kaletra is likely to work for you.

If your virus develops resistance to Kaletra then it may stop working or not work as well for you. You also may not get as much benefit from the other PIs.

Sometimes taking more than one medication can cause drug interactions. Taking certain drugs (including methadone, some antifungals, antidepressants, TB drugs, other HIV drugs, drugs to treat erectile dysfunction such as Viagra, and cholesterol-lowering drugs) with Kaletra can change the amount of each drug in your blood. Your doctor may need to adjust the doses of your drugs to avoid under- or overdosing.

Kaletra decreases the effectiveness of birth control pills, so alternative birth control methods should be used.

Certain medications (including some acid reflux/heartburn drugs, antibiotics, antihistamines, calcium channel blockers, antipsychotics, other PIs, sedatives, migraine medications, and heart medications) should not be taken with Kaletra. Do not take St. John’s wort with Kaletra either.

People taking liquid Kaletra should not take Antabuse (disulfiram) or Flagyl (metronidazole).

Be sure your doctor knows about all the medications you are taking (including over-the-counter, prescription, street drugs, and herbs), even if you only use them occasionally.

For more information and additional resources to check interactions between the particular drugs you are taking, see our info sheet on drug interactions.

It is not uncommon to experience Kaletra side effects. However, if you do, they are likely to be temporary and go away as your body adjusts to the medication. Studies suggest that the new Kaletra tablet is less likely to cause gastrointestinal problems than the old capsule formulation. If you experience any of the side effects listed below, call your doctor for advice. Do not just stop taking your medication.

• Diarrhea
• Nausea
• Vomiting
• Abdominal pain
• Headaches
• Fatigue (unusual tiredness)
• Weakness

More serious side effects:

• Liver toxicity: this may be indicated by elevated liver enzymes or yellowing of the skin and eyes (jaundice).
• Pancreatitis (inflammation of the pancreas): symptoms include sudden or sharp pains in the middle of the abdomen, fever, nausea, or vomiting.
• Lipodystrophy, which may include elevated blood sugar (glucose), elevated lipid levels ( cholesterol and triglycerides), and fat gain or loss in certain areas. Kaletra can cause significant increases in lipid levels. The exact causes of lipodystrophy are not known, but may include HIV and/or HIV drugs. It is unclear if Kaletra will cause or impact other symptoms of lipodystrophy. For more information on lipodystrophy, see our info sheet.
• Some patients taking Kaletra have had changes in their heart rhythm.  It is not know whether these changes were caused by Kaletra or by an interaction between Kaletra and some other medication the patients were taking.  If you have any underlying problems with your heart, discuss with your doctor whether you should take Kaletra.

If you are experiencing persistent, unusual, or serious side effects, call your doctor right away.

Kaletra is a new protease inhibitor and has not been studied in as many people as older HIV drugs.

Research on Kaletra pharmacokinetics (how the drug is processed by the body) has produced conflicting results. Some shows that the drug behaves similarly in the bodies of women and men, some suggests that women eliminate Kaletra faster than men, and some indicates that concentrations of Kaletra reach higher levels (as much as 20 percent higher) in women. The drug manufacturer does not recommend any dose adjustments based on weight or sex.

Studies to date show that Kaletra is one of the most effective HIV drugs. Study 863 compared Zerit (stavudine or d4T) plus Epivir (lamivudine or 3TC) plus Kaletra to Zerit plus Epivir plus Viracept (nelfinavir) in people who had not been treated before with PIs. This study included 20 percent women, or about 130 women out of 653 total participants. In this trial Kaletra worked better that Viracept, especially in people with high viral loads.

Study 888 compared Kaletra to other PIs when used with Viramune (nevirapine) plus nucleoside reverse transcriptase inhibitors (NRTIs). It included 288 participants who had experience taking other PIs, 14 percent (or about 40) of whom were women. In this study, people taking Kaletra were more likely to have undetectable HIV viral loads.

Study AI424-043 looked at 290 participants who had already used HIV drugs, 19 percent (or about 52) of whom were women. In this trial, Kaletra plus two NRTIs worked better than Reyataz (atazanavir) plus two NRTIs.

Study M97-720 has been following 68 people taking Kaletra for nearly five years now, and a majority still have undetectable viral loads.

In terms of side effects, some research suggests that women are more likely to experience gastrointestinal side effects while taking Kaletra, but that men are more likely to develop high blood fat levels. Some studies suggest that the metabolic side effects (lipodystrophy) associated with PIs may be somewhat different in women and men. However, it is still unclear if women are more likely to gain or lose body fat in certain areas than men.

Studies have shown that pregnant women who use HIV drugs can greatly reduce the risk of passing HIV on to their babies. There have been no formal studies of Kaletra during pregnancy.

A Study of 955 births among women in the Antiretroviral Pregnancy Registry from September 2000 through July 2007 showed that the rate of birth defects among women taking Kaletra during pregnancy was no greater than the rate of birth defects among the general population of women giving birth.

Check with your doctor about the best treatment options for you and your baby if you are thinking of getting pregnant.

Click this link for more information about pregnancy.

People who are starting HIV treatment for the first time may develop Immune Reconstitution Syndrome or IRS (also called Immune Reconstitution Inflammatory Syndrome or IRIS). IRS can happen as a result of the immune system getting stronger and responding to an HIV-related infection such as Mycobacterium avium infection (MAC), cytomegalovirus (CMV), Pneumocystis jirovecii pneumonia (PCP), or tuberculosis (TB). People may have been treated for these infections in the past or not even know they have them. If you notice any unusual symptoms soon after starting HIV drugs for the first time, let your doctor know right away so you can be evaluated and, if necessary, treated.