Phase I/II Study of CAMPATH in Patients With Relapsing or Refractory Non-Hodgkin's Lymphoma

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.