Allogene Therapeutics, Inc. (NASDAQ:ALLO), a clinical-stage biotechnology company pioneering the development of allogeneic CAR T (AlloCAR T™) therapies for cancer, in collaboration with its development partner Servier, an independent international pharmaceutical company, announced the release of the abstract related to an upcoming oral presentation at the American Society of Clinical Oncology (ASCO) Annual Meeting. This will be the first data from Allogene’s Phase 1 dose escalation ALPHA study of ALLO-501 in relapsed/refractory non-Hodgkin lymphoma (NHL). This study utilizes ALLO-647, Allogene's anti-CD52 monoclonal antibody (mAb), as a part of its differentiated lymphodepletion regimen.
“As we look ahead to the end of the month to the virtual ASCO meeting, we are excited to present initial clinical data from our first-in-human study of ALLO-501 and ALLO-647,” said Rafael G. Amado, M.D., Executive Vice President of Research & Development and Chief Medical Officer of Allogene. “These findings will provide an early glimpse into the potential of our AlloCAR T pipeline and ALLO-647 based lymphodepletion strategy, which we believe will be foundational in driving the future success and broad applicability of AlloCAR T therapies.”
The ASCO abstract includes preliminary data on the first nine patients treated with escalating doses of ALLO-501 and lower dose (39mg) ALLO-647. No dose limiting toxicities or graft-vs-host disease (GvHD) was observed. The most common Grade (Gr) ≥ 3 adverse events were neutropenia (55.6%), leukopenia (33.3%) and anemia (22.2%). Two patients (22.2%) developed cytokine release syndrome (one Gr1 and one Gr2) that resolved within 72 hours without steroids or tocilizumab. One patient developed Gr1 neurotoxicity that resolved without treatment. One patient developed upper respiratory tract infection (Gr2), CMV (Gr3) and EBV viremia (Gr1), which all resolved. One patient had a Gr2 infusion reaction to ALLO-647 which resolved with antihistamines.
In this limited dataset with a small number of patients, the overall response rate (ORR) was 78% (95% exact CI: 40%, 97%) with three complete responses (CR) and four partial responses (PR). As of the January 2020 data cutoff, there was a median follow up of 2.7 months with four patients in ongoing response and three patients having progressed at 2, 4 and 6 months.
The virtual presentation will include data on 11 patients across ALLO-501 cell dose cohorts and the lower dose (39mg) of ALLO-647, as well as additional patients treated with ALLO-501 and the higher dose (90mg) of ALLO-647. The Phase 1 ALPHA study continues to enroll patients with higher dose ALLO-647 in an effort to optimize lymphodepletion.
This virtual presentation will be available on demand when ASCO releases pre-recorded presentations on May 29, 2020 at 5:00 a.m. PT/8:00 a.m. ET. Allogene will also host a conference call on May 29th following the release of the presentation.
Oral Abstract Session: Hematologic Malignancies - Lymphoma and Chronic Lymphocytic Leukemia
Title: First-in-Human Data of ALLO-501 and ALLO-647 in Relapsed/Refractory Large B-cell or Follicular Lymphoma (R/R LBCL/FL): ALPHA Study.
Presenter: Sattva S. Neelapu, MD, The University of Texas MD Anderson Cancer Center, Department of Lymphoma/Myeloma, Houston, TX
Session Release Date & Time: May 29, 2020 at 5:00 a.m. PT/8:00 a.m. ET
Location: On demand virtual presentation
Allogene is the sponsor of this Phase 1 trial which is designed to assess the safety and tolerability at increasing dose levels of ALLO-501 and ALLO-647 in patients with relapsed/refractory diffuse large B-cell lymphoma and follicular lymphoma.
Allogene expects to initiate enrollment in ALPHA2, a Phase 1 trial with abbreviated dose escalation of ALLO-501A, in Q2 2020. ALLO-501A is the next generation of ALLO-501, which eliminates the rituximab recognition domains, and it is intended for Phase 2 development.