Type of study: Investigator initiated clinical study Study design: One arm, open label, pilot study (n=10) Research question Is treatment with Nevirapine + 3TC sufficient for HIV maintenance Risk Category B (no investigational drugs, non standard Tx) Therapies with 2 drugs are often done in HIV-maintenance. This is a systematical evaluation of such a two drug trial. Rescue therapy is well defined within the protocol. Centers (n) St. Gallen only Participants 10 HIV Patients already on nevirapine + 2 non-nuke RT-Inhibitors Study duration 24 weeks primary observation period after study termination, patients may opt to continue on the bi-therapy. Clinical follow up will then continue Sponsor/Investigator Pietro Vernazza, Kantonsspital St. Gallen Principal investigator Pietro Vernazza, MD. Kantonsspital St. Gallen Co-Investigators Patrick Schmid, MD, Matthias Hoffmann, MD

Financial source None (Pilot Study) If study demonstrates good results, an SNF grant proposal will be submitted

This is a pilot study to evaluate the efficacy of a two drug combination for Long term HIV maintenance therapy.

The study is conducted in order to confirm the feasibility of the combination of Nevirapine and lamivudine (3TC) in patients with long term fully suppressive therapy.

Patients (n=10) with a stable (>6 months) Nevirapine based triple therapy and a full viral load suppression for at least 2 years will continue their therapy for 6 months with Nevirapine+3TC.

The primary endpoint is treatment failure defined as an HIV-RNA value >100 cp/ml, confirmed by a second measurement.

Preliminary stopping rules are defined if results indicate futility. Futility is defined as a situation, where the investigators would stop their plan to conduct a multicenter comparative trial. Futility is reached, when the study documents more than 1 failure in the first 5 patients over 24 weeks of observation or more than 2 failures in all 10 patients.

Only 10 patients will be followed in this single center pilot study.

After an amendement (April 2017) the total number of 20 patients was increased to 20. Futility was defined as more than 2 failures in 20 patients.

Inclusion Criteria:

• HIV-pos, 18 years
• Stable ART, Nevirapine based (plus 2 nukleotide-analogues), at least 6 months
• Viral load suppression at least 24 months Prior to inclusion (<50cp/ml)

Exclusion Criteria:

• chronic Hepatitis B necessitating tenofovir therapy

not planned