Overall Response Rate (ORR) was defined as the percentage of participants whose best response was Complete Response, Complete Response unconfirmed or Partial Response. Participants who had discontinued before any response has been observed, or changed to other anti-lymphoma treatments before response had been observed, were considered as non-responders. Tumor Response was assessed by a modification of the International Lymphoma Workshop Response Criteria, IWRC, Cheson, 1999); CR is defined as the disappearance of all clinical and radiographic evidence of disease; CRu is defined as a CR, with a 1) residual lymph node mass >1.5 cm that has decreased by 75% in the sum of the product of the diameters (SPD). Individual nodes previously confluent decreased by more than 75% in the SPD compared with original mass; 2) indeterminate bone marrow; PR = is defined ≥50% decrease in 6 largest nodes or nodal masses.

ITT population defined as all enrolled participants who received at least one dose of study drug.

Kaplan Meier estimate for the duration of response (DoR) was calculated from the date of the first occurrence of initial response for responders (demonstrating evidence of at least a PR) to the date of first documented disease progression (any new lesion or increase by ≥ 50% of previously involved sites from nadir) or death (without documented progression) for participants who responded; participants who had not progressed (or died) were censored at the last valid assessment.

Includes participants from the ITT population who achieved a PR or better.

The percentage of participants whose best response was CR or CRu. Participants who had discontinued before CR/CRu was observed, or changed to other anti-lymphoma treatments before a CR/CRu response had been observed, were considered as non-responders. CR is defined as the disappearance of all clinical and radiographic evidence of disease; CRu is defined as a CR, with a 1) residual lymph node mass >1.5 cm that has decreased by 75% in the sum of the product of the diameters (SPD). Individual nodes previously confluent decreased by more than 75% in the SPD compared with original mass; 2) indeterminate bone marrow.

The ITT population was defined as all enrolled participants who received at least one dose of study drug.

Kaplan Meier estimates for the duration of CR/CRu was calculated from the date of the first occurrence of CR/CRu to the date of documented disease progression or death (without documented progression) for participants who obtained a CR/CRu; participants who had not progressed (or died) were censored at the last valid assessment.

Includes participants from the ITT population who achieved a CRu or better.

Kaplan Meier estimates of PFS was defined as the start of study drug therapy to the first observation of disease progression or death due to any cause, whichever comes first. If a participant had not progressed or died, PFS was censored at the time of last adequate assessment when the participant was known not to have progressed. For participants who received other anti-lymphoma therapy with no evidence of progression, PFS was censored at time of last adequate tumor assessment with no evidence of progression prior to the start of new anti-lymphoma treatment.

Intent to Treat population defined as all enrolled participants who received at least one dose of study drug.

Kaplan Meier estimate of time to progression was calculated as time from the start of the study drug therapy to the first observation of disease progression. Participants who died without progression were censored at the date of death; otherwise, the censoring rules presented above for PFS applied to the analysis of TTP. Progressive Disease(PD): Appearance of new lesion or increase by ≥50% from previously involved sites from nadir

Intent to Treat population was defined as all enrolled participants who received at least one dose of study drug.

Time to treatment failure (TTF) was calculated from the start of study drug therapy to early discontinuation from treatment due to any cause, including disease progression, toxicity, or death and was based on site-reported data.

Intent to Treat population was defined as all enrolled participants who received at least one dose of study drug.

Time to Response was defined as the time from first dose of study drug to the date of the first response (having at least a PR) and was calculated only for responding participants.

Included participants from the ITT population who achieved a PR or better.

Time to Complete Response (CR+CRu) was defined as the time from the first dose of study drug to the date of the first occurrence of at least CRu and was calculated only for participants with CR or CRu.

Included participants from the ITT population who achieved a CRu or better.

Kaplan Meier estimate of overall survival was calculated from the time the first dose of study drug to death from any cause. Participants who had not died were censored at the last date the participant was known to be alive.

Intent to Treat population defined as all enrolled participants who received at least one dose of study drug.

Adverse events were assessed using National Cancer Institute, Common Terminology Criteria for Adverse Events (NCI CTCAE), Version 3: according to the following scale: Grade 1 = Mild Adverse Event (AE), Grade 2 = Moderate AE, Grade 3 = Severe and Undesirable AE, Grade 4 = Life-threatening or Disabling AE, and Grade 5 = Death; Serious AEs (SAEs) are those that resulted in death, were life-threatening, required or prolonged inpatient hospitalization, resulted in persistent or significant disability/incapacity, congenital anomaly, or resulted in an important medical event that may have jeopardized the patient or required medical or surgical intervention to prevent one of the outcomes listed above. after the first dose of study drug and within 28 days after the last dose. A TEAE is defined as any AE occurring or worsening on or after the first dose of study drug and within 28 days after the last dose of study drug.

The safety population received at least one dose of lenalidomide was used for all safety analysis. This was identical to the ITT population.