Lenalidomide Plus Rituximab Followed by Lenalidomide Versus Rituximab Maintenance for Relapsed/Refractory Follicular, Marginal Zone or Mantle Cell Lymphoma.

Complete Response Rate (CRR)

Best Complete Response Rate (CRR), defined as the proportion of participants with a best response of at least CRu (including CR and CRu) after the first dose date of maintenance therapy and prior to any treatment change.

Time frame: From the first dose date of maintenance therapy up to CR or CRu (up to approximately 432 weeks)

Duration of Response (DOR)

DOR is from initial response (at least CRu) after the first dose date of maintenance therapy and prior to treatment change to documented disease progression or death. Participants who have not progressed or died at the time of the clinical data cutoff date will be censored at the last assessment showing no progression. Participants who change treatment without evidence of disease progression will be censored at the last assessment showing no progression prior to treatment change. Analysis was based on Kaplan Meier estimates.

Time frame: From the initial response (at least PR) after the first dose date of maintenance therapy and prior to treatment change to documented disease progression or death, whichever occurs first (up to approximately 432 weeks)

Time to Next Anti-lymphoma Treatment

Time to next anti-lymphoma treatment is defined as the time from the first dose date of maintenance therapy to the time of first documented administration of new anti-lymphoma therapy. Participants without new treatment therapy will be censored at the last visit. Analysis was based on Kaplan Meier estimates.

Time frame: From the first dose date of maintenance therapy to the time of first documented administration of new anti-lymphoma therapy (up to approximately 300 weeks)

Time to Histological Transformation

Time to histological transformation is defined as from the first dose date of maintenance therapy to the time of histological transformation as measured based on documentation of histological transformation (as assessed by the investigator). Analysis was based on Kaplan Meier estimates. In case of clinical suspicion of transformation, including rapid disease progression, unexpected changes in "B" symptoms or rapidly increasing LDH, a biopsy should be performed. In this clinical trial, histological transformation will be considered disease progression. This endpoint will not be calculated for participants randomized with transformed Follicular Lymphoma (tFL).

Time frame: From the first dose date of maintenance therapy to the time of histological transformation (up to approximately 432 weeks)

Duration of Complete Response (DOCR)

Duration of complete response (DOCR) is calculated as the time from the initial response (CR or CRu) after the first dose date of maintenance therapy and prior to treatment change to documented disease progression or death. Analysis was based on Kaplan Meier estimates. Participants who have not progressed or died at the time of the clinical data cutoff date will be censored at the last assessment showing no progression. Participants who change treatment without evidence of disease progression will be censored at the last assessment showing no progression prior to treatment change.

Time frame: From the initial CR/CRu after the first dose date of maintenance therapy and prior to treatment change to documented disease progression or death, whichever occurs first (up to approximately 432 weeks)

Participants Experiencing Treatment Emergent Adverse Events (TEAEs)

Number of participants experiencing AEs, SAEs, AEs leading to study discontinuation, and AEs of interest (AEIs). An Adverse Event (AE) is defined as any new untoward medical occurrence or worsening of a preexisting medical condition in a clinical investigation participant administered study treatment and that does not necessarily have a causal relationship with this treatment. SAEs is any untoward medical occurrence that, at any dose: results in death; is life-threatening; requires inpatient hospitalization; results significant disability; or is a congenital anomaly/birth defect. TEAEs are defined as AEs with an onset date on or after the first dose of study treatment up to 30 days after the last dose of study treatment in the study, or if a pre-existing condition worsens in severity or becomes serious after receiving the first dose of study treatment.

Time frame: From first dose up to 30 days after last dose (up to approximately 64 weeks for induction period and 427 weeks for maintenance period)

Participants Experiencing Adverse Events Related to Vital Signs

The number of participants who experienced adverse events related to vital sign measurements

Time frame: From first dose up to 30 days after last dose (up to approximately 64 weeks for induction period and 427 weeks for maintenance period)

Participants With Grade 3 or Grade 4 Hematology Parameters

Clinical laboratory values in induction period include any laboratory values that are taken after the first dose date of induction therapy through 28 days after the last dose date of induction therapy or before the first dose date of maintenance therapy, whichever is earlier. Graded according to the NCI CTCAE version 4.03, except for tumor flare reaction, which is accessed using NCI CTCAE version 3.0. Participants with zero maximum grade are excluded.

Time frame: From first dose up to 30 days after last dose (up to approximately 64 weeks for induction period and 427 weeks for maintenance period)

Participants With Grade 3 or Grade 4 Serum Chemistry Parameters

Clinical laboratory values in induction period include any laboratory values that are taken after the first dose date of induction therapy through 28 days after the last dose date of therapy. Graded according to the NCI CTCAE version 4.03, except for tumor flare reaction, which is accessed using NCI CTCAE version 3.0. Participants with zero maximum grade are excluded.

Time frame: From first dose up to 30 days after last dose (up to approximately 64 weeks for induction period and 427 weeks for maintenance period)