Inclusion Criteria:

• Confirmation of the willingness of the patient to participate in this study after being informed on all the aspects of the trial that may influence their decision, signing and dating the written informed consent form approved by the Ethics Committee.
• The patient is 18 years of age or older.
• (Documented) HIV-1 infection.
• Receiving treatment with ZDV+3TC+ABC (in continuous antiretroviral treatment, without discontinuation periods, for the past 6 months).
• There is confirmation that during the 6 months prior to inclusion in the study the viral burdens were below 50 copies/mL.
• A viral burden below 50 copies/mL no more than 30 days before starting the study.
• No previous history of virological failure while on antiretroviral treatment with protease inhibitors (PIs). That is, they have never switched protease inhibitors for suspected or documented virological failure. The changes in protease inhibitor due solely to toxicity, simplification or optimization are acceptable.
• Clinical evidence of moderate to severe lipoatrophy (according to the case definition as scoring >- 2. For inclusion in the study, the subject should have moderate to severe lipoatrophy in at least one site, and defined by the physician.
• Absence of signs of acute disease.
• Patient has not been treated for an active opportunistic infection within the 30 days prior to the baseline visit.
• Patient with Karnofsky index >- 70.
• During the study, the patient does not require and agrees not to take any of the following drugs that are contraindicated with LPV/r: astemizole, terfenadine, midazolam, triazolam, cisapride, certain ergot derivatives (ergotamine, dihydroergotamine, ergonovine, methylergonovine), pimozide, propafenone, and flecainide. Rifampin, a potent enzyme inducer, should not be administered with the study medication due to the possibility of a significant decrease in LPV/r concentrations during concomitant administration, nor drugs contraindicated with 3TC and ABC that in principle should not be being taken, as they are part of the treatment at the screening.
• Patient agrees not to take any medication, including over-the-counter medicines, alcohol, drugs, or herbal preparations without the knowledge and approval of the principal investigator.
• Laboratory tests have been performed on the patients in the past 30 days:
• G/dL hemoglobin >8.0
• Absolute neutrophil count 750 cells/microl
• Platelet count 20,000/microl
• ALT or AST <5 x upper normal limit (UNL)
• Creatinine <1. 5 x UNL
• Triglycerides <750 mg/dL.
• For women, a negative result of a pregnancy test is available and they agree to use throughout the study a barrier contraceptive method of proven reliability in the investigator's opinion.

Exclusion Criteria:

• Patients with a history of virological failure on treatment with PIs; that is, that they have at some point switched to PIs for confirmed or documented virological failure.
• Patients with positive serum hepatitis B surface antigen.
• Patients requiring treatment with drugs where combination with LPV/r is contraindicated.
• Presence of active opportunistic disease or wasting syndrome or under antitumoral treatment with chemotherapy.
• Patients treated in the previous 16 weeks with agents susceptible to insulin (glitazones or metformin), anabolic steroids, growth hormone or any agent that could interfere with the study drugs.
• Active drug addiction or psychiatric disease that may prevent protocol compliance. Use of cannabis or being on methadone treatment are excepted, provided protocol compliance is not compromised in the investigator's opinion.
• Pregnant women or nursing mothers, and women of childbearing age if they do not agree to use a barrier contraceptive method throughout the study of proven reliability in the investigator's opinion.
• In the opinion of the principal investigator, the patient is unlikely to comply with the study protocol, or the patient is not eligible for any other reason.