Ofatumumab + Chlorambucil vs Chlorambucil Monotherapy in Previously Untreated Patients With Chronic Lymphocytic Leukemia

OR is defined as the number of participants achieving an objective response (complete response [CR], CR with incomplete bone marrow recovery [CRi], partial response [PR], and nodular PR [nPR]). CR (all the criteria at least 2 months after last treatment): no lymphadenopathy (Ly) > 1.5 cm/ hepatomegaly/ splenomegaly/ constitutional symptoms; neutrophils >1500 per microliter (µL), platelets (PL) >100,000/µL, hemoglobin (Hb) >11 grams/deciliter (g/dL), lymphocytes (LC) <4000/µL, bone marrow (BM) sample must be normocellular for age, <30% LC, no lymphoid nodule. CRi: CR criteria, persistent anemia/thrombocytopenia/neutropenia unrelated to CLL but related to drug toxicity. PR: >=50% decrease in LC, Ly, size of liver and spleen and at least one of the following results: PL >100,000/µL or 50% improvement over Baseline (BL), Hb >11 g/dL or 50% improvement over BL. nPR: persistent nodules BM.

MRD was performed by flow cytometry on a bone marrow or peripheral blood sample taken at least 2 months after final treatment. MRD negative was defined as less than one CLL cell per 10000 leukocytes.

Overall survival is defined as the time from randomization to death due to any cause. Each participant was followed at the time when the total IRC-assessed PFS events occurred. Participants who had not died were censored at the date of last contact.

Time to response is defined as the time from randomization to the first response (CR, CRi, nPR, or PR). CR (all the criteria at least 2 months after last treatment): no lymphadenopathy (Ly) > 1.5 cm/ hepatomegaly/ splenomegaly/ constitutional symptoms; neutrophils >1500 per microliter (µL), platelets (PL) >100,000/µL, hemoglobin (Hb) >11 grams/deciliter (g/dL), lymphocytes (LC) <4000/µL, bone marrow (BM) sample must be normocellular for age, <30% LC, no lymphoid nodule. CRi: CR criteria, persistent anemia/thrombocytopenia/neutropenia unrelated to CLL but related to drug toxicity. PR: >=50% decrease in LC, Ly, size of liver and spleen and at least one of the following results: PL >100,000/µL or 50% improvement over Baseline (BL), Hb >11 g/dL or 50% improvement over BL. nPR: persistent nodules BM. Participants with unknown or missing responses were considered as non-responders. Only responders (CR, CRi, PR, nPR) were included in the analysis.

DOR is defined as the time from the initial response (CR, CRi, nPR, or PR) to the first documented sign of PD or death due to any cause. PD requires at least one of the following: lymphadenopathy, appearance of any new lesion such as enlarged lymph nodes (>1.5 cm) spleen or liver or other infiltrates or an increase by 50% or more in the greatest diameter of any previous site; an increase by 50% or more in the previously noted enlargement of the liver or spleen, an increase by 50% or more in the numbers of blood lymphocytes with at least 5000 lymphocytes per microliter, transformation to a more aggressive histology, or occurrence of cytopenia attributable to chronic lymphocytic leukaemia. Par. who were alive and had not progressed at the time of analysis or if a progression event occurred after extensive lost-to-follow-up time (>= 12 weeks) were censored at the date of the last visit with adequate assessment. Par. with unknown or missing responses were considered as non-responders.

Time to progression is defined as the time from the date of randomization to disease progression (PD). PD requires at least one of the following: lymphadenopathy, appearance of any new lesion such as enlarged lymph nodes (>1.5 cm) spleen or liver or other infiltrates or an increase by 50% or more in the greatest diameter of any previous site; an increase by 50% or more in the previously noted enlargement of the liver or spleen, an increase by 50% or more in the numbers of blood lymphocytes with at least 5000 lymphocytes per microliter, transformation to a more aggressive histology, or occurrence of cytopenia attributable to chronic lymphocytic leukaemia. Participants who were alive and had not progressed at the time of analysis or if a progression event occurred after extensive lost-to-follow-up time were censored at the date of the last visit with adequate assessment.

Time to next therapy is defined as the time from randomization until the start of the next-line of treatment.

The ECOG performance status scales and criteria are used by doctors and researchers to assess how a participant's disease is progressing, how the disease affects the daily living, and determines appropriate treatment and prognosis. Grade 0, fully active, able to carry on all pre-disease performance without restriction. Grade 1, restricted in physically strenuous activity but ambulatory and able to carry out work of a light or sedentary nature, e.g., light house work, office work. Grade 2, ambulatory and capable of all selfcare, but unable to carry out any work activities; up and about more than 50% of waking hours. Grade 3, capable of only limited selfcare; confined to bed or chair more than 50% of waking hours. Grade 4, completely disabled; cannot carry on any selfcare; totally confined to bed or chair. Grade 5, dead. Participants with an ECOG performance status of 0 or 1 are shown..

Assessment for the presence of the following symptoms were performed at Screening, Day 1 of each treatment cycle and at every Follow-up visit: night sweats (without signs of infection); unexplained, unintentional weight loss >= 10% within the previous 6 months; recurrent, unexplained fever of greater than 38 degrees celsius or 100.5 degrees fahrenheit for 2 weeks; and extreme fatigue. The best response refers to overall best response in terms of CR, CRi, PR or nPR. Data are presented for constitutional response= yes and no.

Serum samples for analysis of HAHA were collected at Baseline (Screening), Cycle 4 Day 1 (after 3 months of treatment), and at 1 month and 6 months post last dose of ofatumumab. All samples were first tested in a screening step; positive samples from the screening were further evaluated in a confirmation test. The confirmed positive samples were reported as HAHA-positive and further evaluated in the titration test to obtain a titer of HAHA.

Blood samples were collected to assess the plasma concentration of ofatumumab. Maximum concentration (Cmax) and observed drug concentration prior to the next dose (Ctrough) were determined. Blood samples were collected from participants who received ofatumumab plus chlorambucil at pre-dose and 0.5 hours after the end of the ofatumumab infusion at treatment Cycle 1 and Cycle 4 (Days 1, 8, and 85). In addition, pre-dose samples were collected prior to ofatumumab administration at Cycles 2, 3, 5, 6, 9 and 12 (Days 29, 57, 113, 141, 225 and 309), depending on the duration of treatment.

Plasma clearance is defined as the plasma volume which is totally cleared of drug per unit of time. Blood samples were collected from participants who received ofatumumab plus chlorambucil at pre-dose and 0.5 hours after the end of the ofatumumab infusion at treatment Cycle 1 and Cycle 4 (Days 1, 8, and 85). In addition, pre-dose samples were collected prior to the ofatumumab administration at Cycles 2, 3, 5, 6, 9 and 12 (Days 29, 57, 113, 141, 225 and 309), depending on duration of treatment. Samples were also collected during clinic visits on Day 15 (during Cycle 1) and Day 43 (during Cycle 2) and at 1, 3, and 6 months post-treatment.

Area under the concentration time curve over the dosing interval [AUC(0-tau)] is a measure of drug exposure over time. AUC(0-tau) is defined as the area under the ofatumumab plasma concentration-time curve from dosing to time tau, where tau is the length of the dosing interval of ofatumumab. For estimation of AUC(0-tau), blood samples were collected from participants who received ofatumumab plus chlorambucil at pre-dose and 0.5 hous after the end of the ofatumumab infusion at treatment Cycle 1 and Cycle 4 (Days 1, 8, and 85). In addition, pre-dose samples were collected prior to the ofatumumab administration at Cycles 2, 3, 5, 6, 9 and 12 (Days 29, 57, 113, 141, 225 and 309), depending on duration of treatment. Samples were also collected during clinic visits on Day 15 (during Cycle 1) and Day 43 (during Cycle 2) and at 1, 3, and 6 months post-treatment.

Volume of distribution at steady state (Vss) is defined as the distribution of a drug between plasma and the rest of the body at steady state. Blood samples were collected from participants who received ofatumumab plus chlorambucil at predose and 0.5 hour after the end of the ofatumumab infusion at treatment Cycle 1 and Cycle 4 (Days 1, 8, and 85). In addition, pre-dose samples were collected prior to ofatumumab administration at Cycles 2, 3, 5, 6, 9 and 12 (Days 29, 57, 113, 141, 225 and 309), depending on the duration of the treatment. Samples were also collected during clinic visits on Day 15 (during Cycle 1) and Day 43 (during Cycle 2) and at 1, 3, and 6 months post-treatment.

The terminal half-life (t1/2) of ofatumumab is defined as the time required for the plasma concentration of ofatumumab to reach half of its original concentration. Blood samples were collected to assess the plasma half-life of ofatumumab. Blood samples were collected from participants who received ofatumumab plus chlorambucil pre-dose and 0.5 hours after the end of the ofatumumab infusion at treatment Cycle 1 and Cycle 4 (Days 1, 8, and 85). In addition, pre-dose samples were collected prior to ofatumumab administration at Cycles 2, 3, 5, 6, 9 and 12 (Days 29, 57, 113, 141, 225 and 309), depending on the duration of the treatment. Samples were also collected during clinic visits on Day 15 (during Cycle 1) and Day 43 (during Cycle 2) and at 1, 3, and 6 months post-treatment.

Blood samples for the determination of serum concentrations of chlorambucil and its metabolite PAAM were collected from participants in a substudy on Cycle 3 Day 1. The maximum observed concentration (Cmax) of chlorambucil and PAAM normalized to the administered dose was determined as a measure of exposure and compared to reference data from a prior study (LEUA1001) [No NCT number available for this study; GlaxoSmithKline Document Number RM1998/00449/00].

Blood samples for the determination of serum concentrations of chlorambucil and its metabolite PAAM were collected from participants in a substudy on Cycle 3 Day 1. The area under the plasma concentration-time curve from time zero (pre-dose) extrapolated to infinite time (AUC[0-inf]) and over 6 hours (AUC[0-6]) of chlorambucil and AUC(0-6) of PAAM normalized to the administered dose was determined as a measure of exposure and compared to reference data from a prior study (LEUA1001) [No NCT number available for this study; GlaxoSmithKline Document Number RM1998/00449/00].

HRQOL was assessed using European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTCQLQC30), Chronic Lymphocytic Leukemia module (EORTC QLQ-CLL16), EuorQoL-Five Dimension (EQ-5D), and HCQ. Period (P)1 (Day 85, Day 169, Day 253) and P2 (scheduled follow-up (FU) and withdrawal visits) analysis were considered. Baseline (BL) for P1 was defined as score from screening visit and BL for P2 was defined as the last on-treatment score. The 2 principal QoL outcomes were pre-specified as the Global Health scale (GHS/QOL) of the EORTC QLQ-C30 and fatigue scale of the EORTC QLQ-CLL16. For EORTC QLQ-C30,GHS/Qol, the possible scale range was 0-100 (with 100 being 'best') and a positive difference from BL is indicative of better functioning (range -100 to +100). For the EORTC QLQ-CLL16 fatigue scale, the possible scale range was 0-100 (with 0 being 'best') and a negative difference from BL represents an improvement in fatigue (range -100 to +100).

An AE is defined as any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a medicinal product. An SAE is defined as any untoward medical occurrence that, at any dose, results in death, is life threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity, is a congenital anomaly/birth defect, or is an event of possible drug-induced liver injury. Refer to the general Adverse AE/SAE module for a complete list of AEs and SAEs.

An AE is defined as any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a medicinal product. An SAE is defined as any untoward medical occurrence that, at any dose, results in death, is life threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity, is a congenital anomaly/birth defect, or is an event of possible drug-induced liver injury. Refer to the general Adverse AE/SAE module for a complete list of AEs and SAEs. Maximum severity grades were evaluated according to the National Cancer Institute (NCI) Common Toxicity Criteria for Adverse Events (CTCAE) version 3.0 (1, mild; 2, moderate; 3, severe; 4, life-threatening/disabling; 5, death).

Participants with a Grade 3 or Grade 4 myelosuppression (anemia, neutropenia, and thrombocytopenia) are presented by treatment cycle. Myelosuppression is defined as the decrease in the ability of the bone marrow to produce blood cells. AEs were graded according to NCI common terminology criteria for adverse events (CTCAE) grade, version 3.0 (1, mild; 2, moderate; 3, severe; 4, life-threatening/disabling; 5, death).

AIHA is a disease where the body's immune system fails to recognize red blood cells as "self" and begins destroying these red blood cells. The number of participants diagnosed with AIHA are presented.

Participants who received no transfusion and at least one transfusion during the study are presented. Participants who took any blood products are counted in this table.

Immunoglobulins, or antibodies, are large proteins used by the immune system to identify and neutralize foreign particles such as bacteria and viruses. Their normal blood levels indicate proper immune status. Low levels indicate immuno-suppression. IgA, IgG, and IgM were measured in the blood samples of the participants. Baseline IgA, IgG, and IgM values are the last pre-dose assessment values performed on Cycle 1 Day 1. Change from Baseline was calculated as the post-Baseline value minus the Baseline value.