A Study Of PF-05280586 (Rituximab-Pfizer) Or MabThera® (Rituximab-EU) For The First-Line Treatment Of Patients With CD20-Positive, Low Tumor Burden, Follicular Lymphoma (REFLECTIONS B328-06)

ORR was defined as the percentage of participants who achieved complete response (CR) or partial response (PR) in accordance with the revised response criteria for malignant lymphoma (Cheson 2007). CR was defined as disappearance of all evidence of disease. PR was defined as regression of measureable disease and no new sites.

An AE was any untoward medical occurrence in participants who received study drug without regard to possibility of causal relationship. SAE was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly. Treatment-emergent were events after first dose of study drug that were absent before treatment or that worsened relative to pretreatment state. AEs included both serious and non-serious.

Treatment-related AE was any untoward medical occurrence attributed to study drug in a participant who received study drug. SAE was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly. Treatment-emergent were events after first dose of study drug that were absent before treatment or that worsened relative to pretreatment state. Relatedness to treatment was assessed by investigator. AEs included both serious and non-serious AEs.

An AE was any untoward medical occurrence in participant who received study drug without regard to possibility of causal relationship. Grade 1=Mild, asymptomatic or mild symptoms, Grade 2=Moderate; minimal, local or noninvasive intervention indicated, Grade 3 (Severe) events=unacceptable or intolerable events, significantly interrupting usual daily activity, require systemic drug therapy/other treatment. Grade 4 (Life threatening) events caused participant to be in imminent danger of death. Grade 5 = death. Treatment-emergent were events after first dose of study drug that were absent before treatment or that worsened relative to pretreatment state.

Treatment-related AE was any untoward medical occurrence attributed to study drug in a participant who received study drug. Grade 1=Mild, asymptomatic or mild symptoms, Grade 2=Moderate; minimal, local or noninvasive intervention indicated; Grade 3 (Severe) events=unacceptable or intolerable events, significantly interrupting usual daily activity, require systemic drug therapy/other treatment. Grade 4 (Life-threatening) events caused participant to be in imminent danger of death. Grade 5 = death. Treatment-emergent were events after first dose of study drug that were absent before treatment or that worsened relative to pretreatment state.

Criteria for clinically significant laboratory abnormalities included total bilirubin (TB) less than (<) 2*upper limit of normal (ULN), alanine aminotransferase (ALT)<3*ULN; TB<2*ULN, ALT more than (>) 3 equal to (=) *ULN; TB<2*ULN, aspartate aminotransferase (AST)<3*ULN; TB<2*ULN, AST>=3*ULN. Data for only those categories are reported for which at least one participant had clinically significant laboratory abnormality.

TTF was defined as the time (in months) from date of randomization to first progression of disease based on central review, death due to any cause, or permanent discontinuation from treatment, or discontinuation from study for any reason, whichever came first. Progression was defined as any new lesion or increase by greater than or equal to (>=) 50% of previously involved sites from nadir. TTF was calculated using Kaplan-Meier method.

PFS was defined as the time (in months) from date of randomization to first progression of disease (PD) based on central review or death due to any cause in the absence of documented PD. PD was defined as any new lesion or increase by >=50% of previously involved sites from nadir. PFS was calculated using Kaplan-Meier method.

Complete Remission (CR) was defined as disappearance of all evidence of disease. CR was assessed by central review based on scans done at Week 26.

DOR was defined as the time (in months) from date of the first documentation of overall response (CR or PR) to the first documentation of progressive disease (PD) based on central review or to death due to any cause in the absence of documented PD. CR was defined as disappearance of all evidence of disease. PR was defined as regression of measureable disease and no new sites. PD was defined as any new lesion or increase by >=50% of previously involved sites from nadir. DOR was calculated using Kaplan-Meier method.

Overall survival was defined as the time (in months) from date of randomization to death due to any cause. For participants who were alive, overall survival was censored at the last contact. Overall survival was calculated using Kaplan-Meier method.

Human serum ADA samples were analyzed for the presence or absence of anti-rituximab antibodies or anti-PF-05280586 antibodies using the validated drug-specific assay with a tiered approach using screening, confirmation and titer/quantitation. Human NAb serum samples testing ADA positive were analyzed for the presence or absence of neutralizing anti-rituximab antibody and neutralizing anti-PF-05280586 antibody using the validated drug-specific assay with a tiered approach using screening, confirmation and titer/quantitation. Participants with their ADA titer >= 1.88 were considered to be ADA positive. Only participants with a positive ADA result were further tested for NAb.

Immune-based adverse effects included infusion related reaction (IRR), adverse events which fulfill Sampson's criteria, and adverse events which belong to the Standardized Medical Dictionary for Regulatory Activities (MedDRA) Queries (SMQs) anaphylaxis or hypersensitivity reactions. Potential allergic and anaphylactic reactions were identified programmatically based on the criteria of Sampson et al, (2006).