Study of Acalabrutinib Versus Chlorambucil Plus Rituximab in Adult Subjects With Previously Untreated Chronic Lymphocytic Leukemia

PFS was defined as the time from randomization to PD (assessed by BICR according to International Workshop on Chronic Lymphocytic Leukaemia [iwCLL] 2018 guideline criteria) or death due to any cause. PD was defined as meeting at least 1 of the below criteria of groups(g) A or B. gA: increase of ≥50% from baseline (BL) or from response in lymph nodes or liver and/or spleen size; any constitutional symptoms; increase of ≥50% over nadir with absolute count ≥ 5×10^9/liter (L) in circulating lymphocyte count (CLC); gB: decrease of ≥50% from BL secondary to CLL in platelet count; decrease of ≥2 gram per deciliter (g/dL) from BL secondary to CLL in hemoglobin (Hb); increase of CLL cells by ≥50% on successive biopsies in bone marrow (BM). Median PFS was calculated using Kaplan-Meier method and its confidence interval (CI) using Brookmeyer-Crowley method.

ORR:percentage of participants with complete response(CR),CR with incomplete BM recovery(CRi), partial response(PR)/nodular PR(nPR) assessed by BICR;investigator per IWCLL 2018 criteria at/before initiation of subsequent anti-cancer therapy.CR:No lymph nodes(target lesions)≥1.5 centimeter(cm), spleen<13cm,normal liver;CLC,no constitutional symptoms,platelets≥100,000/microliter(μL),Hb≥11.0 g/dL,BM:normocellular,no CLL cells&B-lymphoid nodules.PR:atleast 2 gA parameters;1 gB parameter need to improve if previously abnormal.If only 1 parameter of both gA,B was abnormal prior to therapy,only 1 needs to improve.gA:Decrease≥50% from BL in lymph nodes,liver & or spleen size,CLC;any constitutional symptoms, gB:platelet≥100,000/μL or increase 50% over BL;Hb≥11g/dL or increase≥50% over BL;BM:presence of CLL cells/B-lymphoid nodules/not done.CRi:all CR criteria+persistent anemia,thrombocytopenia or neutropenia unrelated to CLL,related to drug toxicity.nPR:CR+presence of B-lymphoid nodules in BM.

DOR was defined as the time from response (date of first documented response) to PD or death (absence of PD) as judged by BICR and investigator. PD was defined as meeting at least 1 of the below criteria of group A or group B. Group A: Increase of ≥ 50% from BL or from response in lymph nodes or liver and/or spleen size; any constitutional symptoms; increase of ≥50% over nadir with absolute count ≥ 5×10^9/L in CLC; group B: decrease of ≥50% from BL secondary to CLL in platelet count; decrease of ≥2 g/dL from BL secondary to CLL in hemoglobin; increase of CLL cells by ≥50% on successive biopsies in marrow. Median DOR was calculated using Kaplan-Meier method and its CI using Brookmeyer-Crowley method.

TTNT was defined as the time from the date of randomization to the date of initiation of non-protocol-specified anti-CLL therapy (either medication or radiotherapy for CLL) or death from any cause, whichever occurred first. Median TTNT was calculated using Kaplan-Meier method and its CI was calculated using Brookmeyer-Crowley method.

OS was defined as the time from the date of randomization until death due to any cause. The median OS was calculated using Kaplan-Meier method and its CI was calculated using Brookmeyer-Crowley method.

The MRD negative rate was defined as the percentage of participants with MRD-negativity (defined as <1 CLL cell per 10,000 leukocytes) measured in the peripheral blood by flow cytometry.

Blood samples were collected to determine the concentration of acalabrutinib and its metabolite ACP-5862 in plasma.

An adverse event (AE) was any untoward medical occurrence (other than progression of the malignancy under evaluation) in participant or clinical study participant administered medicinal product and which does not necessarily had a causal relationship with treatment. A serious adverse event (SAE) was an AE occurring during any study phase, that fulfilled 1 or more of following criteria: resulted in death, was life-threatening, required in-participant hospitalization/prolongation of existing hospitalization, resulted in persistent or significant disability or incapacity, was congenital abnormality or birth defect, and was an important medical event that jeopardized participant or required medical treatment to prevent 1 of outcomes listed above. TEAE was any AE that occurred or worsened in severity on or after date of the first dose of study drug up to 30 days after last dose of study drug or prior to initiation of a new anti-CLL therapy, whichever occurred first.