To observe the efficacy and safety of simplified therapy regimen for treating with HIV-1 infected patients in Chinese real word.

This is an phase IV open-label, multicenter, single-arm clinical trial in. A total of 600 cases were planned to be recruited. These cases were given simplified therapy regimen of lopinavir (200mg) and ritonavir (50mg) (500mg, oral, bid ) combined with lamivudine (300mg, oral, qd. The observation duration is thirty-sixth months. Patients will be followed up before and 12, 24 and 36 months after receiving the simplified regimen, observing the viral inhibition rate and the change of CD4 cell count, the safety and patients'compliance.

Inclusion Criteria:

1. HIV-1 infection confirmed
2. Agree to use simplified therapy regimen.
3. Agree to detect CD4 count at least once per half a year

Exclusion Criteria:

1. Have participated in HIV vaccine clinical trial or other drug trials in the past three months.
2. Patients who could not complete the scheduled follow-up (such as weakness and poor compliance).
3. Patients who have the history of resistance or allergy to LPV/r or 3TC.

Patients who are prescribed to take the simplified therapy regimen (LPV/r+ 3TC) because they are unable to tolerate the side-effect of or are not fit for the first-line free regimen in China, for example renal failure or osteoporosis, according to clinical judgment, no matter of the HIV-RNA viral loads and CD4 cell counts.