A Phase 1 interventional study of ALLO-501 and ALLO-647 in Relapsed/Refractory Large B Cell Lymphoma and Relapsed/Refractory Follicular Lymphoma, sponsored by Allogene Therapeutics. Completed at 7 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-03-02.
Sponsored by Allogene Therapeutics · Phase 1, Interventional, and Treatment
The purpose of the ALPHA study is to assess the safety, efficacy, cell kinetics and immunogenicity of ALLO-501 in adults with relapsed or refractory large B-cell lymphoma or follicular lymphoma after a lymphodepletion regimen comprising fludarabine, cyclophosphamide, and ALLO-647.
1,891 studies on the registry are indexed under Lymphoma, Follicular; 290 are open to participants now.
This study's enrollment of 50 is close to the median of 48 across 1,503 interventional studies indexed under Lymphoma, Follicular.
Browse Lymphoma, Follicular studies →Allogene Therapeutics is the lead sponsor of 9 studies on the registry; 3 are open to participants now.
Compared within Lymphoma, Follicular, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Recurrence. The counts are of registry records indexed under each term, refreshed daily. How we classify →
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
After a transplant from a donor, the donor’s immune cells attack the recipient’s body, often the skin, gut or liver.
Relapsed and refractory
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Line of therapy
A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Measurable disease
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Allogeneic and autologous transplant
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GVHD (graft-versus-host disease)
After a transplant from a donor, the donor’s immune cells attack the recipient’s body, often the skin, gut or liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Genetic: ALLO-501 · Biological: ALLO-647 · Drug: Fludarabine · Drug: Cyclophosphamide
ALLO-501 is an allogeneic CAR T cell therapy targeting CD19
ALLO-647 is a monoclonal antibody that recognizes a CD52 antigen
Chemotherapy for lymphodepletion
Chemotherapy for lymphodepletion
Proportion of subjects experiencing Dose Limiting Toxicities at increasing doses of ALLO-501
Dose limiting toxicity is defined as protocol-defined ALLO-501-related adverse events with onset within 28 days following infusion
Time frame: 28 days
Proportion of patients experiencing Dose Limiting Toxicity with ALLO-647 in combination with fludarabine/cyclophosphamide administered prior to ALLO-501
Dose-limiting toxicity is defined as protocol-defined ALLO-647-related adverse events with onset within 33 days following 1st infusion
Time frame: 33 days
Ran from May 2019 to primary completion in Oct 2021, 29 months.
Of 84 industry-sponsored phase 1 interventional studies under Lymphoma, Follicular, half reached primary completion within 44 months of starting (the median), counting those still running; a quarter within 21 and three quarters within 71. This study's 29 months is below that.
Counting every sponsor, half of 173 studies reached it within 51 months; a quarter within 30 and three quarters within 80.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Feb 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Anti-CD52 Monoclonal Antibody ALLO-647
Allogene Therapeutics