Inclusion Criteria:

- Pathological confirmation of HCC or noninvasive criteria following AASLD guidelines

- Measurable or evaluable disease based on RECIST criteria

- Progressive disease on sorafenib or intolerance to sorafenib

- ECOG performance status 0-2

- Child Pugh Class A or B

- Adequate hepatic, bone marrow, and renal function

Exclusion Criteria:

- Prior ABT-888 or other PARP inhibitor treatment

- Anticipation of need for major surgery during the study

- Any of the following within 6 months before enrollment: myocardial infarction,
severe/unstable angina, congestive heart failure, or severe pulmonary disease

- Women who are pregnant or lactating

- Women and men of child-bearing potential who are not using a reliable form of
contraception

- History of allergic reactions attributed to compounds of similar chemical or biologic
composition to ABT-888 and temozolomide

- Concurrent malignancy (i.e. malignancy other than hepatocellular cancer) unless 1)
the subject has been curatively treated and disease free for at least 2 years or 2)
the cancer was non-melanoma skin cancer or early cervical cancer.

- Uncontrolled intercurrent illness including, but not limited to, ongoing or active
infection (excluding active hepatitis B or C) or psychiatric illness/ social
situations that would limit compliance with study requirements