Two lersivirine 250 milligram (mg) tablets (equivalent to lersivirine 500 mg), a placebo tablet matched to lersivirine and a placebo tablet matched to efavirenz orally once daily along with tenofovir disoproxil fumarate (DF) 300 mg tablet and emtricitabine 200 mg tablet orally once daily, in the evening up to 96 weeks. Participants enrolled in pharmacokinetic (PK) substudy switched to lersivirine morning dosing regimen, received 2 Lersivirine 250 mg tablets, a placebo tablet matched to lersivirine orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet were continued in the evening in PK substudy. Evening dosing was continued for the remainder of the study up to Week 96.

Three Lersivirine 250 mg tablets (equivalent to lersivirine 750 mg) and a placebo tablet matched to efavirenz orally once daily along with tenofovir DF 300 mg and emtricitabine 200 mg tablet orally once daily, in the evening up to 96 weeks. Participants enrolled in PK substudy switched to morning dosing regimen, received 3 Lersivirine 250 mg tablets orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet were continued in the evening in PK substudy. Evening dosing was continued for the remainder of the study up to Week 96.

Three placebo tablets matched to lersivirine, efavirenz 600 mg tablet orally once daily along with tenofovir DF 300 mg and emtricitabine 200 mg tablet orally once daily, in the evening up to 96 weeks. Participants enrolled in PK substudy switched to morning dosing regimen, received 3 placebo tablets matched to lersivirine and efavirenz 600 mg tablet orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. Efavirenz 600 mg tablet, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet were continued in the evening in PK substudy. Evening dosing was continued for the remainder of the study up to Week 96.

Two lersivirine 250 milligram (mg) tablets (equivalent to lersivirine 500 mg), a placebo tablet matched to lersivirine and a placebo tablet matched to efavirenz orally once daily along with tenofovir disoproxil fumarate (DF) 300 mg tablet and emtricitabine 200 mg tablet orally once daily, in the evening up to 96 weeks. Participants enrolled in pharmacokinetic (PK) substudy switched to lersivirine morning dosing regimen, received 2 Lersivirine 250 mg tablets, a placebo tablet matched to lersivirine orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet were continued in the evening in PK substudy. Evening dosing was continued for the remainder of the study up to Week 96.

Two lersivirine 250 milligram (mg) tablets (equivalent to lersivirine 500 mg), a placebo tablet matched to lersivirine and a placebo tablet matched to efavirenz orally once daily along with tenofovir disoproxil fumarate (DF) 300 mg tablet and emtricitabine 200 mg tablet orally once daily, in the evening up to 96 weeks. Participants enrolled in pharmacokinetic (PK) substudy switched to lersivirine morning dosing regimen, received 2 Lersivirine 250 mg tablets, a placebo tablet matched to lersivirine orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet were continued in the evening in PK substudy. Evening dosing was continued for the remainder of the study up to Week 96.

Two lersivirine 250 milligram (mg) tablets (equivalent to lersivirine 500 mg), a placebo tablet matched to lersivirine and a placebo tablet matched to efavirenz orally once daily along with tenofovir disoproxil fumarate (DF) 300 mg tablet and emtricitabine 200 mg tablet orally once daily, in the evening up to 96 weeks. Participants enrolled in pharmacokinetic (PK) substudy switched to lersivirine morning dosing regimen, received 2 Lersivirine 250 mg tablets, a placebo tablet matched to lersivirine orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet were continued in the evening in PK substudy. Evening dosing was continued for the remainder of the study up to Week 96.

Two lersivirine 250 milligram (mg) tablets (equivalent to lersivirine 500 mg), a placebo tablet matched to lersivirine and a placebo tablet matched to efavirenz orally once daily along with tenofovir disoproxil fumarate (DF) 300 mg tablet and emtricitabine 200 mg tablet orally once daily, in the evening up to 96 weeks. Participants enrolled in pharmacokinetic (PK) substudy switched to lersivirine morning dosing regimen, received 2 Lersivirine 250 mg tablets, a placebo tablet matched to lersivirine orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet were continued in the evening in PK substudy. Evening dosing was continued for the remainder of the study up to Week 96.

Two lersivirine 250 milligram (mg) tablets (equivalent to lersivirine 500 mg), a placebo tablet matched to lersivirine and a placebo tablet matched to efavirenz orally once daily along with tenofovir disoproxil fumarate (DF) 300 mg tablet and emtricitabine 200 mg tablet orally once daily, in the evening up to 96 weeks. Participants enrolled in pharmacokinetic (PK) substudy switched to lersivirine morning dosing regimen, received 2 Lersivirine 250 mg tablets, a placebo tablet matched to lersivirine orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet were continued in the evening in PK substudy. Evening dosing was continued for the remainder of the study up to Week 96.

Two lersivirine 250 milligram (mg) tablets (equivalent to lersivirine 500 mg), a placebo tablet matched to lersivirine and a placebo tablet matched to efavirenz orally once daily along with tenofovir disoproxil fumarate (DF) 300 mg tablet and emtricitabine 200 mg tablet orally once daily, in the evening up to 96 weeks. Participants enrolled in pharmacokinetic (PK) substudy switched to lersivirine morning dosing regimen, received 2 Lersivirine 250 mg tablets, a placebo tablet matched to lersivirine orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet were continued in the evening in PK substudy. Evening dosing was continued for the remainder of the study up to Week 96.

Two lersivirine 250 milligram (mg) tablets (equivalent to lersivirine 500 mg), a placebo tablet matched to lersivirine and a placebo tablet matched to efavirenz orally once daily along with tenofovir disoproxil fumarate (DF) 300 mg tablet and emtricitabine 200 mg tablet orally once daily, in the evening up to 96 weeks. Participants enrolled in pharmacokinetic (PK) substudy switched to lersivirine morning dosing regimen, received 2 Lersivirine 250 mg tablets, a placebo tablet matched to lersivirine orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet were continued in the evening in PK substudy. Evening dosing was continued for the remainder of the study up to Week 96.

Two lersivirine 250 milligram (mg) tablets (equivalent to lersivirine 500 mg), a placebo tablet matched to lersivirine and a placebo tablet matched to efavirenz orally once daily along with tenofovir disoproxil fumarate (DF) 300 mg tablet and emtricitabine 200 mg tablet orally once daily, in the evening up to 96 weeks. Participants enrolled in pharmacokinetic (PK) substudy switched to lersivirine morning dosing regimen, received 2 Lersivirine 250 mg tablets, a placebo tablet matched to lersivirine orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet were continued in the evening in PK substudy. Evening dosing was continued for the remainder of the study up to Week 96.

Two lersivirine 250 milligram (mg) tablets (equivalent to lersivirine 500 mg), a placebo tablet matched to lersivirine and a placebo tablet matched to efavirenz orally once daily along with tenofovir disoproxil fumarate (DF) 300 mg tablet and emtricitabine 200 mg tablet orally once daily, in the evening up to 96 weeks. Participants enrolled in pharmacokinetic (PK) substudy switched to lersivirine morning dosing regimen, received 2 Lersivirine 250 mg tablets, a placebo tablet matched to lersivirine orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet were continued in the evening in PK substudy. Evening dosing was continued for the remainder of the study up to Week 96.

Two lersivirine 250 milligram (mg) tablets (equivalent to lersivirine 500 mg), a placebo tablet matched to lersivirine and a placebo tablet matched to efavirenz orally once daily along with tenofovir disoproxil fumarate (DF) 300 mg tablet and emtricitabine 200 mg tablet orally once daily, in the evening up to 96 weeks. Participants enrolled in pharmacokinetic (PK) substudy switched to lersivirine morning dosing regimen, received 2 Lersivirine 250 mg tablets, a placebo tablet matched to lersivirine orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet were continued in the evening in PK substudy. Evening dosing was continued for the remainder of the study up to Week 96.

Participants enrolled in PK substudy received 2 Lersivirine 250 mg tablets and a placebo tablet matched to lersivirine orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet orally once daily were continued in the evening in PK substudy.

Participants enrolled in PK substudy received 3 Lersivirine 250 mg tablets orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet orally once daily were continued in the evening in PK substudy.

Participants enrolled in PK substudy received 2 Lersivirine 250 mg tablets and a placebo tablet matched to lersivirine orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet orally once daily were continued in the evening in PK substudy.

Participants enrolled in PK substudy received 3 Lersivirine 250 mg tablets orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet orally once daily were continued in the evening in PK substudy.

Participants enrolled in PK substudy received 2 Lersivirine 250 mg tablets and a placebo tablet matched to lersivirine orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet orally once daily were continued in the evening in PK substudy.

Participants enrolled in PK substudy received 3 Lersivirine 250 mg tablets orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet orally once daily were continued in the evening in PK substudy.

Participants enrolled in PK substudy received 2 Lersivirine 250 mg tablets and a placebo tablet matched to lersivirine orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet orally once daily were continued in the evening in PK substudy.

Participants enrolled in PK substudy received 3 Lersivirine 250 mg tablets orally once daily in the morning for 7 days prior to Week 4, and in the morning and evening on 1 day following Week 4. A placebo tablet matched to efavirenz, tenofovir DF 300 mg tablet and emtricitabine 200 mg tablet orally once daily were continued in the evening in PK substudy.