A Preliminary Assessment of Safety and Antiviral Activity of Open-label Entecavir in Subjects With Chronic Hepatitis B Following Monotherapy in Other Entecavir Trials

Overall Study: Number of Participants With Death As Outcome, Any Adverse Event (AE), Grade 3-4 AEs, Serious Adverse Events (SAEs), and Discontinuations Due to AEs

Time Frame: Continuously from Day 1 through Week 240

An AE is a new unfavorable symptom, sign, or disease or worsening of a preexisting condition that may not be causally related to treatment. An SAE is an unfavorable medical event that at any dose results in death, persistent or significant disability/incapacity, or drug dependency or abuse; is life-threatening, an important medical event, or a congenital anomaly/birth defect; or requires or prolongs hospitalization. Grade 1=mild; Grade 2=moderate; Grade 3=severe; Grade 4=life-threatening or disabling. ALT=alanine transaminase; ULN=upper limit of normal.

Overall Study: Number of Participants With Normal Hematology Values at Baseline and Abnormalities in Hematology Laboratory Test Results Through Week 240

Time Frame: Day 1 of treatment through Week 240

Hemoglobin (g/dL): Grade (Gr) 1=9.5-11.0; Gr 2=8.0-\<9.5; Gr 3=6.5-\<8.0; Gr 4=\<6.5 White blood cells (cells/mm\^3): Gr 1=2,500-\<4,000; Gr 2=1,000-\<2,500; Gr 3=800-\<1,000; Gr 4=\<800. Neutrophils (cells/mm\^3): Gr 1=1000-\<1500; Gr 2=750-\<1000; Gr 3=500-\<750; Gr 4=\<500. Platelets (cells/mm\^3): Gr 1=75,000-99,000; Gr 2=50,000-\<75,000; Gr 3=20,000-\<50,000; Gr 4=\<20,000. Prothrombin time (seconds): Gr 1=1.01-\<1.26\*ULN; Gr 2=1.26-\<1.51 \*ULN; Gr 3=1.51-3\*ULN; Gr 4=\>3\*ULN. INR: Gr 1=1.24-1.5; Gr 2=1.5-2; Gr 3=2-3; Gr 4=\>3. INR=international normalized ratio; ULN=upper limit of normal. .

Overall Study: Number of Participants With Normal Pancreatic Enzyme and Renal Function Values at Baseline and Abnormalities in Pancreatic Enzyme and Renal Function Laboratory Test Results at End of Dosing

Time Frame: Day 1 of treatment through Week 240

Amylase: Grade 1=1.10-\<1.40\*ULN; Grade 2=1.40-\< 2.10\*ULN; Grade 3=2.10-5.00\*ULN; Grade 4=\>5.00\*ULN. Lipase: Grade 1.1-\<1.4\*ULN; Grade 2=1.4-\<2.1\*ULN; Grade 3=2.1-5.0\*ULN; Grade 4=\>5.0\*ULN. Creatinine: Grade 1=1.10-\< 1.60\*ULN; Grade 2=1.60-\<3.10\*ULN; Grade 3=3.10-6.00\*ULN; Grade 4=\>6.00\*ULN. Blood urea nitrogen (BUN): Grade 1=1.25-\<2.60\*ULN; Grade 2=2.60-\<5.10\*ULN; Grade 3=5.10-10\*ULN; Grade 4=\>10\*ULN. ULN=upper limit of normal.

Overall Study: Number of Participants With Normal Electrolyte and Fasting Glucose Values at Baseline and Abnormalities in Electrolyte and Fasting Glucose Laboratory Test Results at End of Dosing

Time Frame: Day 1 of treatment through Week 240

Hypochloremia: Grade (Gr) 1=90-93; Gr 2=85-\<90; Gr 3=80-\<85; Gr 4=40-\<80. Hyperchloremia: Gr 1=113-\<117; Gr 2=117-\<121; Gr 3=121-125; Gr 4\>125. Hypocarbia: Gr 1=19-21; Gr 2=15-\<19; Gr 3=41-45; Gr 4=\>45. Hypercarbia: Gr 1=31-36; Gr 2=37-40; Gr 3=41-45; Gr 4=\>45. Hyponatremia: Gr 1=130-132; Gr 2=123-\<130; Gr 3=116-\<123; Gr 4\<116. Hypernatremia: Gr 1=148-\<151; Gr 2=151-\<158; Gr 3=158-165; Gr 4=\>165. Hypokalemia: Gr 1=3-3.4; Gr 2=2.5-\<3; Gr 3=2-\<2.5; Gr 4=\<2. Hyperkalemia: Gr 1=5.6-\<6.1; G2=6.1-\<6.6; Gr 3=6.6-7; Gr 4=\>7. Hypoglycemia: Gr 1=55-64; Gr 2=40-\<55; Gr 3=30-\< 40; G4=-\<30. Hyperglycemia: Gr 1=116-\<161; Gr 2=161-\<251; Gr 3=251-500; Gr 4\>500.

Week 144: Number of Participants With Death As Outcome, Any AE, Grade 3-4 AEs, SAEs, Discontinuations Due to AEs, and Abnormalities in Selected Laboratory Test Results

Time Frame: Continuously from Day 1 through Week 144

An AE is any new unfavorable symptom, sign, or disease or worsening of a preexisting condition that does not necessarily have a causal relationship with treatment. An SAE is any unfavorable medical event that at any dose results in death, persistent or significant disability/incapacity, or drug dependency or abuse; is life-threatening, an important medical event, or a congenital anomaly/birth defect; or requires or prolongs hospitalization. Grade 1=mild; Grade 2=moderate; Grade 3=severe; Grade 4=life-threatening or disabling. AST=aspartate aminotransferase; ULN=upper limit of normal.

Week 192: Number of Participants With Death As Outcome, Any AE, Grade 3-4 AEs, SAEs, Discontinuations Due to AEs, and Abnormalities in Selected Laboratory Test Results

Time Frame: Continuously from Day 1 through Week 192

An AE is any new unfavorable symptom, sign, or disease or worsening of a preexisting condition that does not necessarily have a causal relationship with treatment. An SAE is any unfavorable medical event that at any dose results in death, persistent or significant disability/incapacity, or drug dependency or abuse; is life-threatening, an important medical event, or a congenital anomaly/birth defect; or requires or prolongs hospitalization. CTC Grade 1=mild; Grade 2=moderate; Grade 3=severe; Grade 4=life-threatening or disabling. ALT=alanine aminotransferase; ULN=upper limit of normal.

Off-treatment Follow-up: Percentage of Participants With Sustained Hepatitis B Virus (HBV) DNA <10,000 Copies by Polymerase Chain Reaction (PCR) Assay (Amendment 11 Cohort)

Time Frame: End of dosing to Week 48 off-treatment follow-up

The Amendment 11 Cohort consisted of participants who were hepatitis B e antigen (HBeAg) negative and who had compensated liver disease, a minimum of 192 weeks (4 years) of treatment with entecavir, HBV DNA \<300 copies/mL by PCR assay for ≥48 weeks before end of dosing and on the last observed result ≤24 weeks prior to end of dosing, and serum ALT levels ≤1.0\*ULN at the end of study drug dosing.ALT=alanine aminotransferase; ULN=upper limit of normal.