Evaluation of Lymphodepletion With ALLO-647 in Adults With R/R Large B Cell Lymphoma Receiving ALLO-501A Allogeneic CAR T Cell Therapy

To assess the clinical efficacy of ALLO-647 (in a lymphodepletion regimen before ALLO-501A) compared to FC alone as measured by PFS and assessed by Independent Review Committee (IRC) in subjects with R/R (Relapsed / Refractory) LBCL (Large B Cell Lymphoma). In this study, PFS is defined as the time from randomization to disease progression, or relapse per the Lugano classification criteria (Cheson et al, 2014) as assessed by IRC or death.

Time frame: Up to 60 months

Population: Intent-to-Treat (ITT) Analysis Set: All randomized participants. Data does not exist as assessment of efficacy per Independent Review Committee was not performed.

To characterize the depth and duration of lymphodepletion with and without ALLO-647, as assessed by lymphocyte count.

Time frame: From study treatment to study discontinuation, death, withdrawal of consent, or date of initiation of another anticancer therapy, whichever occurs first, for a maximum of 9 months. Only Day 28 lymphocyte counts are available for both participants.

Population: Safety-Analysis Set: All randomized participants who received at least one (partial or complete) dose of FCA/FC or ALLO-501A. Only Day 28 lymphocyte counts are available for both participants.

To characterize the efficacy of ALLO-647 as measured by Duration of Response (DOR) and assessed by Independent Review Committee (IRC) between treatment arms. DOR is defined as time from the first observed response to disease progression or relapse (per IRC) or death.

Time frame: Up to 60 months

Population: ITT Analysis Set: All randomized participants. Data does not exist as assessment of efficacy per Independent Review Committee was not performed.

To characterize the efficacy of ALLO-647 as measured by response rate per investigator, Duration of Response (DOR), Event-Free Survival (EFS), Progression-Free Survival (PFS), assessed by investigator assessments between treatment arms. DOR is defined as time from the first observed response to disease progression or relapse per investigator assessment, or death. EFS is defined as the time from randomization to disease progression or relapse per investigator assessment per the Lugano classification criteria, new anti-cancer therapy, or death. PFS is defined as time from the randomization to progression or relapse per investigator assessment per the Lugano classification criteria, or death.

Time frame: Neither participant was a responder, therefore DOR was not followed. EFS and PFS were followed from first dose of study treatment until disease progression, subsequent anticancer therapy, or death. EFS and PFS were followed for 0.99 to 1.84 months.

Population: ITT Analysis Set: All randomized participants. Duration of Response data is not applicable since there are no responders per investigator assessment.

To assess clinical efficacy of ALLO-647 with FC (in a lymphodepletion regimen before ALLO-501A) compared to FC alone as measured by Event-Free Survival (EFS) and assessed by Independent Review Committee (IRC) in subjects with R/R LBCL. EFS is defined as the time from randomization to disease progression or relapse per the Lugano classification criteria 2014 as assessed by IRC, new anti-cancer therapy, or death.

Time frame: Up to 60 months

Population: ITT Analysis Set: All randomized participants. Data does not exist as assessment of efficacy per Independent Review Committee was not performed.

To evaluate the overall safety profile of ALLO-501A following lymphodepletion.

Time frame: Up to 60 months, study completion, or death, whichever occurs earlier. Related TEAEs were followed for 4.5 and 10.09 months for each participant in the FCA and FC arm, respectively.

Population: Safety-Analysis Set: All randomized participants who received at least one (partial or complete) dose of ALLO-647 or ALLO-501A.

To evaluate the overall safety profile of ALLO-647 by comparing FCA lymphodepletion with FC lymphodepletion.

Time frame: Up to 60 months, study completion, or death, whichever occurs earlier. TEAEs were followed for 4.5 and 10.09 months for each participant in the FCA and FC arm, respectively.

Population: Safety-Analysis Set: All randomized participants who received at least one (partial or complete) dose of ALLO-647 or ALLO-501A.

To characterize the efficacy of ALLO-647 as measured by response rate per investigator, Overall Response Rate (ORR), and assessed by investigator assessments between treatment arms. ORR in FCA vs FC alone per investigator assessment at any time up through commencement of new anti-cancer therapy or withdrawal of consent.

Time frame: Overall Response Rate was followed until disease progression or subsequent anticancer therapy, whichever occurred earlier. Specifically, ORR was followed for 0.99 to 1.84 months for each participant in the FCA and FC arm, respectively.

Population: ITT Analysis Set: All randomized participants.

To assess the clinical efficacy of ALLO-647 as measured by ORR and assessed by Independent Review Committee (IRC) between treatment arms. ORR is defined as best overall response (Complete Response and Partial Response, assessed using the Lugano classification criteria 2014; Cheson , et al, 2014) by IRC at any time up through commencement of new anti-cancer therapy or withdrawal of consent.

Time frame: Up to 60 months

Population: ITT Analysis Set: All randomized participants. Data does not exist as assessment of efficacy per Independent Review Committee was not performed.

To characterize the efficacy of ALLO-647 as measured by OS, defined as the time from randomization to death.

Time frame: Up to 60 months, study completion, or death, whichever occurs earlier. Specifically, OS was followed for 4.5 and 10.09 months for each participant in the FCA and FC arm, respectively.

Population: ITT Analysis Set: All randomized participants.