Lenalidomide Plus Rituximab for Recurrent/Refractory CNS and Intraocular Lymphoma

Rationale for the Proposed Study

There is evidence that immunomodulatory drugs such as lenalidomide stimulate immune effectors
such as natural killer (NK) cells, and thus promote rituximab efficacy via ADCC. Because of
the evidence for synergy between rituximab and lenalidomide in NHL, patients who do not
respond to lenalidomide monotherapy will receive combined intravenous plus intraventricular
rituximab in addition to lenalidomide. To maximize delivery to the central nervous system
(CNS), the investigators propose to administer rituximab via both intravenous and
intraventricular routes. The rationale for intraventricular administration of rituximab is
the demonstration that approximately 0.1% of systemically administered rituximab penetrates
the cerebral spinal fluid (CSF) but that intraventricular administration of rituximab is both
feasible and achieves high concentrations that are associated with anti-lymphoma activity.
This study will thus build upon the two Phase 1 trials of intraventricular rituximab that
have been conducted at UCSF to define the safety of the intraventricular route of
administration; this study will, however, be the first to evaluate the combination of
intraventricular plus intravenous treatment.

The rationale for intravenous administration of rituximab in recurrent CNS lymphoma is that
the blood-brain-barrier is likely partially disrupted, particularly when there is
lymphoma-associated contrast enhancement detectable on the MRI, and the fact that there is
evidence for activity when rituximab is administered intravenously, both as monotherapy
(Batchelor et al., 2011) and potentially in combination with chemotherapy.

Inclusion Criteria:

- Ability to give written informed consent and willingness to comply with the
requirements of the protocol

- Age eighteen years or older

- Tumors must be CD20+ on prior pathologic analysis

- All prospective participants must have an Ommaya reservoir (or equivalent ventricular
access device) inserted as part of their standard clinical care prior to initiation of
study treatment.

- No concurrent methotrexate, thiotepa, cytarabine, or investigational agents

- Absolute neutrophil count (ANC) > 1,500 (growth factors permitted)

- Platelets >50,000 (platelet transfusion allowed)

- Total bilirubin
- AST (SGOT) and ALT (SGPT)
- Stable dose of glucocorticoids pre-therapy. If patients are receiving dexamethasone,
the dose of dexamethasone should not increase during the 96 hours prior to initiation
of therapy.

- Renal function assessed by calculated creatinine clearance. Patients must have
calculated creatinine clearance >/= 60ml/min by Cockcroft-Gault formula or 24 hour
urine demonstrating CrCl >/= 60ml/min .

- Females of childbearing potential (FCBPs)† must have a negative serum or urine
pregnancy test with a sensitivity of at least 25 mIU/mL within 10 - 14 days and again
within 24 hours prior to receiving lenalidomide for Cycle 1 and must either commit to
continued abstinence from heterosexual intercourse or begin TWO acceptable methods of
birth control, one highly effective method and one additional effective method AT THE
SAME TIME, at least 28 days before she starts taking lenalidomide. FCBPs must also
agree to ongoing pregnancy testing and for 28 days after receiving their last dose of
lenalidomide.

- Men must agree to use a latex condom during sexual contact with a FCBP even if they
have had a successful vasectomy.

- Able to take aspirin (81 or 325 mg) daily as prophylactic anticoagulation (patients
intolerant to aspirin may use warfarin or low molecular weight heparin).

- All study participants must be registered into the mandatory RevAssist® program, and
be willing and able to comply with the requirements of RevAssist®.

Exclusion Criteria:

- Intraventricular chemotherapy or radiation therapy within 4 days of starting treatment

- Intravenous rituximab within 30 days of starting treatment

- Persistent neurotoxicity from intraventricular methotrexate, cytarabine, thiotepa

- Anticipated survival of less than 1 month

- Pregnant women and women of child-bearing potential who are not using an effective
method of birth control.

- Known hypersensitivity to thalidomide or lenalidomide

- The development of erythema nodosum if characterized by a desquamating rash while
taking thalidomide or similar drugs.

- Known seropositive for or active viral infection with human immunodeficiency virus
(HIV), hepatitis B virus (HBV) or hepatitis C virus (HCV). Patients who are
seropositive because of hepatitis B virus vaccine are eligible.

- Contraindication to aspirin. If unable to take aspirin, contraindication to warfarin
or low molecular weight heparin.