Inclusion Criteria:

Patients must have:

- Pathologically confirmed diagnosis of relapsing or refractory non-Hodgkin's lymphoma
that has failed conventional therapy.

- Measurable disease (lesions that can be accurately measured by CT scan and a greatest
transverse diameter larger or equal to 1 cm or palpable lesions that both diameters
larger or equal to 2 cm).

- Life expectancy of at least 12 weeks. - World Health Organization (WHO) performance
status (PS) of 0, 1, or 2.

- Adequate marrow and organ function (details are listed in the protocol).

- Female patients with childbearing potential must have a negative serum pregnancy test
within 2 weeks prior to enrollment. Male and female patients must agree to use an
effective contraceptive method while on study treatment, if appropriate, and for a
minimum of 6 months following study therapy.

- Signed, written informed consent.

Exclusion Criteria: Patients must not have:

- Prior autologous bone marrow or stem cell transplant within 6 months of study entry.

- A history of prior allogeneic bone marrow transplant or organ transplant.

- Previously untreated non-Hodgkin's lymphoma.

- Previously treated with CAMPATH.

- Patients with bulky disease, ie any single mass > 7.5cm.

- Prior radiotherapy to the only site of measurable disease.

- Medical condition requiring chronic use of oral, high-dose corticosteroids.

- Autoimmune thrombocytopenia.

- Use of investigational agents within previous 30 days or any anti-cancer therapy
within the previous 3 weeks. Patients must have recovered from all acute toxicities
of any prior therapy.

- Past history of anaphylaxis following exposure to humanized monoclonal antibodies.

- Active, uncontrolled infection, including human immunodeficiency virus (HIV)
positive.

- Active secondary malignancy.

- Active central nervous system (CNS) involvement with NHL.

- Pregnant or lactating women. Male or female patients who do not agree to use
effective contraceptive method(s) during the study.

- Any significant concurrent disease or illness that would, in the opinion of the
investigator, compromise patient safety or compliance, or interfere with the
interpretation of study results.