Inclusion Criteria:

- Age >=18 years, either sex, any race.

- Eastern Cooperative Oncology group performance status of 0 or 1.

- Adequate hematologic, renal, and hepatic organ function and laboratory parameters.

- For subjects with MCL:

- Diagnosis of MCL according to the World Health Organization (WHO) criteria.

- Received at least one prior chemotherapeutic regimen, but no more than two
regimens including stem cell transplantation..

- Measurable or assessable disease by the Revised Response Criteria for Malignant
Lymphoma.

- For subjects with B-CLL

- Documented B-CLL according to the National Cancer Institute Working Group
(NCI-WG) criteria.

- Received at least one prior alkylating agent-based regimen and one fludarabine-
or pentostatin-containing regimen, but must not have received more than two
prior regimens.

- Measurable or assessable disease by NCI-WG criteria.

Exclusion Criteria:

- Known central nervous system involvement of MCL or B-CLL.

- Previous treatment with SCH 727965 or other cyclin-dependent kinase inhibitors.

- For MCL, previous treatment with bortezomib.

- For B-CLL, previous treatment with alemtuzumab.

- Known HIV infection.

- Known active hepatitis B or C.