Extension Study of Idelalisib in Participants With Chronic Lymphocytic Leukemia (CLL) Who Participated in GS-US-312-0116 (NCT01539512)

ORR was defined as the percentage of participants who achieved a complete response (CR) or partial response (PR). The determination of CLL response and progression were based on standardized International Workshop on Chronic Lymphocytic Leukemia (IWCLL) criteria, as specifically modified for this study to reflect current recommendations which considered the mechanism of action of idelalisib and similar drugs. CR and PR are defined in Protocol Amendment 9, Sections 7.5.1 and 7.5.2.

Lymph node response rate was defined as the percentage of participants who achieved a ≥ 50% decrease from baseline in the sum of the products of the greatest perpendicular diameters (SPD) of index lymph nodes.

CR rate was defined as the percentage of participants who achieved a CR (full definition in Protocol Amendment 9, Section 7.5.1). The determination of CLL response and progression were based on standardized IWCLL criteria, as specifically modified for this study to reflect current recommendations which considered the mechanism of action of idelalisib and similar drugs.

TTR was defined as the time interval from start of study therapy to the first documentation of CR or PR.

DOR was defined as the time interval from the first documentation of CR or PR to the earlier of the first documentation of definitive disease progression or death from any cause. DOR was analyzed using KM estimates.

The best percent change from baseline in lymph node area (SPD) was defined as the largest decrease in tumor size during the study. The baseline SPD was the last value prior to the baseline reference date. For the participants who only had increases in tumor size from baseline, the smallest increase was considered as the best change from baseline in SPD.

Splenomegaly response rate was defined as the percentage of participants with baseline splenomegaly who achieved an on-study normalization or a 50% decrease (minimum 2 cm) from baseline in the enlargement of the splenic longest vertical dimension (LVD) (by imaging).

Hepatomegaly response rate was defined as the percentage of participants with baseline hepatomegaly who achieved an on-study normalization or a 50% decrease (minimum 2 cm) from baseline in the hepatic LVD (by imaging).

ALC response rate was defined as the percentage of participants with baseline lymphocytosis (ALC ≥ 4 x 10^9 cells/L) who achieved an on-study ALC < 4 x 10^9 cells/L or demonstrated a ≥ 50% decrease in ALC from baseline; ALC values within 4 weeks post-baseline were excluded from the ALC response rate evaluation.

Platelet response rate was defined as the percentage of participants with baseline thrombocytopenia (platelet count < 100 x 10^9/L) who achieved an on-study platelet count ≥ 100 x 10^9/L or demonstrated a ≥ 50% increase in platelet count from baseline; platelet values within 4 weeks post-baseline or after 8 days post transfusion were excluded from the platelet response rate evaluation.

Hemoglobin response rate was defined as the percentage of participants with baseline anemia (hemoglobin < 110 g/L [11.0 g/dL]) who achieved an on-study hemoglobin ≥ 110 g/L (11.0 g/dL) or demonstrated a ≥ 50% increase in hemoglobin from baseline; hemoglobin values within 4 weeks post-baseline or after 4 weeks of receiving packed cell/whole blood transfusion or after 6 weeks of receiving exogenous growth factors (eg, darbepoetin alfa) were excluded from the hemoglobin response evaluation.

Neutrophil response rate was defined as the percentage of participants with baseline neutropenia (absolute neutrophil count [ANC] ≤ 1.5 x 10^9/L) who achieved an ANC > 1.5 x 10^9/L or demonstrated a ≥ 50% increase in ANC from baseline; ANC values within 4 weeks of post-baseline or after 2 weeks of receiving exogenous growth factors (eg, filgrastim, granulocyte-colony stimulating factor [G-CSF], lenograstim) or after 4 weeks of receiving Neulasta® were excluded from response evaluation.

Overall survival was defined as the time interval from start of study therapy to death from any cause. Overall survival was analyzed using KM estimates. Data presented includes all available survival information from Study GS-US-312-0116 (including data in long-term follow-up) and Study GS-US-312-0117 (including any data in long-term follow-up) up to the database finalization dates. Data from surviving participants were censored at the last time that the participant was known to be alive on study or long-term follow-up. Data presented includes all participants who were randomized to Study GS-US-312-0116 regardless if they entered Study GS-US-312-0117 or not.

The FACT-Leu questionnaire included subscales for physical well-being (PWB, 7 items), social/family well-being (SWB, 7 items), emotional well-being (EWB, 6 items), functional well-being (FWB, 7 items), and additional concerns or Leukemia-Specific Subscale (LeuS, 17 items). The FACT-Leu scoring guide identified those negatively stated items that must have been reversed before being added to obtain subscale totals. Negatively stated items were reversed by subtracting the response from "4". After reversing proper items, all subscale items were summed to get total subscale scores with the range of 0-28, 0-28, 0-24, 0-28, 0-68 for PWB, SWB, EWB, FWB, and LeuS, respectively. FACT-Leu total score ranged from 0 to 176. Higher scores indicated a better quality of life. Best change from baseline was defined as the highest value of change from baseline among all postbaseline visits. For participants who did not enter Study GS-US-312-0117, baseline values were from Study GS-US-312-0116.

KPS is a tool used to measure the ability to perform ordinary tasks. The score ranges from 0 to 100, with a higher score indicating that the participant is better able to carry out daily activities. Best change from baseline was defined as the highest value of change from baseline among all postbaseline visits. For participants who did not enter Study GS-US-312-0117, baseline values were from Study GS-US-312-0116.

The percent of average on-treatment biomarker concentration of baseline (%Baseline) was used to evaluate the overall pharmacodynamics change on the biomarkers with IDL treatment. The average on-treatment biomarker concentration is calculated using area under curve (AUC) following the trapezoidal rule. The biomarkers with median AUC value of 100 indicated no overall on-treatment biomarker changes compared to the baseline. The biomarkers with median AUC value greater than 100 or less than 100 indicated an increase or decrease, respectively, on-treatment biomarker changes from the baseline.

Adherence percentage was calculated as the sum of tablets dispensed - the sum of tablets returned divided by the sum of the overall dosing period (total daily tablets x dosing duration), taking into account investigator-prescribed interruptions.

Change in health status was defined as the change from baseline in overall health and single-item dimension scores as assessed using the EQ-5D utility measure. Percentage of participants with different level of problem were reported. Level 1: indicated no problem; Level 2: indicated some problems; and Level 3: indicated extreme problems. For participants who did not enter Study GS-US-312-0117, baseline values were from Study GS-US-312-0116.