Breaking News

Allogene Therapeutics presented data from multiple studies across lead anti-CD19 AlloCAR T therapy programs in two poster presentations at the 2021 American Society of Clinical Oncology Annual Meeting being held virtually June 4 - 8, 2021. The ASCO presentations include data from Phase 1 ALPHA and ALPHA2 trials in relapsed/refractory non-Hodgkin lymphoma, developed in collaboration with Servier, and presented in the Developmental Therapeutics - Immunotherapy session by Frederick L. Locke, M.D., Co-Leader, Moffitt Immuno-Oncology Program, Vice Chair and Associate Member Department of Blood and Marrow Transplant and Cellular Immunotherapy, Moffitt Cancer Center. Safety, pharmacokinetic and pharmacodynamic data from ALLO-647, a component of the Company's differentiated lymphodepletion regimen, will be presented in the same session by Michael Tees, M.D., M.P.H., Associate Member Physician, Colorado Blood Cancer Institute, Sarah Cannon Research Institute. Due to the virtual nature of the meeting, the ASCO presentations were finalized in advance of Allogene's CD19 Forum on May 19, 2021. As such, data presented at the CD19 Forum, accessible via this link and included below, is more comprehensive and reflects information collected as of May 12, 2021 from the ALPHA and ALPHA2 studies. The Company intends to initiate a Phase 2 trial with ALLO-501A, pending regulatory feedback, by the end of 2021. The next clinical update on the CD19 program is planned for Q4 2021. Data presented from the ALPHA trial supports the ability of a single administration of ALLO-501 to generate deep and durable responses at a rate that is similar to approved autologous CAR T therapies. As of the April 19, 2021 data cutoff, 42 patients were enrolled and 41 received ALLO-501, including nine who had previously received autologous CAR T treatment. The one patient not treated was enrolled but removed from the study prior to lymphodepletion due to lymphoma related obstructive kidney disease. In the trial, 98% of patients received ALLO-501 and the median and mean time from enrollment to the start of therapy was five days. Responses were observed across all cell doses and tumor histologies and follicular lymphoma. The percent of these patients remaining in complete response at six months following a single infusion was 29%, with 36% in LBCL and 24% in FL. An additional four FL patients in response have yet to reach the six month timepoint. As of May 12, 2021, three LBCL patients remain in CR and eight FL patients remain in CR, with the longest ongoing CRs at 15 months. Redosing led to clinical responses, with an overall Treatment Failure Free Survival for autologous naive patients of 64% and 61% at six months for FL and LBCL, respectively. ALLO-647 was used in lymphodepletion with fludarabine/cyclophosphamide at doses ranging from 39mg to 90mg. No dose limiting toxicities or graft-vs-host disease were observed and one case of Grade 3 Immune Effector Cell-Associated Neurotoxicity Syndrome was reported. Cytokine release syndrome occurred in 27% of patients, was limited to Grade 1 or 2, and was manageable with standard protocols. Infection rates were similar to those observed in autologous CAR T trials. During this study, there were five treatment-emergent deaths in the absence of disease progression, one each from pneumonia, arrythmia, and stroke, and two instances of COVID-19 acquired in the community setting. Three of these patients were in ongoing CR at the time of death. ALLO-501A is a next generation anti-CD19 AlloCAR T candidate intended for a pivotal trial and is engineered without the rituximab recognition domains included in ALLO-501. This trial is only enrolling patients with relapsed/refractory LBCL. Following promising efficacy data from patients treated at dose level 2 patient enrollment in ALPHA2 focused on exploration of a consolidated dosing strategy that enabled patients who did not progress following an initial dose of ALLO-501A to receive a second, scheduled dose of cells. In consolidation dosing, 60mg ALLO-647 was provided with Flu/Cy for lymphodepletion before the first cell administration at DL2, and 30mg ALLO-647 with no Flu/Cy was provided for lymphodepletion before the second cell infusion at DL2 to patients with selective hematologic criteria. As of the April 19, 2021 data cutoff, 13 patients were enrolled and 12 patients were treated with ALLO-501A. One patient was treated with ALLO-647 but not ALLO-501A and deemed unable to proceed due to disease progression. Nine patients treated at the targeted 120M cell dose were evaluable for efficacy were CAR T naive, except for one who received prior autologous CAR T and previously had a 16-week CR followed by relapse. Data from these nine patients demonstrate efficacy and safety for ALLO-501A consistent with that observed for ALLO-501 in the ALPHA trial. As of May 12, 2021, all of the CRs remain ongoing, with a median follow-up of 2.3 months. Of the eight patients treated in the consolidation cohorts across both ALPHA studies, the ORR was 75% and CR rate was 63%, with four patients converting from a partial response at day 28 to a CR at day 56. No dose limiting toxicities, GvHD or ICANS were observed in ALPHA2.