A Phase 2/3 interventional study of RAPA-501 Autologous T stem cells in Amyotrophic Lateral Sclerosis, sponsored by Rapa Therapeutics LLC. Recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-29.
Sponsored by Rapa Therapeutics LLC · Phase 2/3, Interventional, and Treatment
RAPA-501-ALS is a phase 2/3 expansion cohort study of RAPA-501 autologous hybrid TREG/Th2 cells in patients living with amyotrophic lateral sclerosis (pwALS).
This is an open-label, non-randomized, multi-center phase 2/3 study evaluating RAPA-501 T stem cell therapy in pwALS on an expansion cohort. Amyotrophic lateral sclerosis (ALS) is a rare disease that is also considered an orphan disease according to the Orphan Drug Act.
After a subject consents to the study, an apheresis procedure will be performed to collect cells to manufacture the investigational product, RAPA-501 T stem cells. RAPA-501 T stem cells are manufactured ex vivo using epigenetic reprogramming to yield a T stem cell population that is enriched for a dual anti-inflammatory phenotype based on hybrid TREG and Th2 differentiation. RAPA-501 cells express both the TREG and Th2 transcription factors FOXP3 and GATA3, are enriched for expression of the ATP ectonucleotidase molecules CD39 and CD73, are enriched for the T cell homing molecule CD103, and suppress both effector T cell inflammatory molecules and CNS microglial cell inflammatory molecules.
This study consists of a phase 2/3 expansion cohort that is evaluating RAPA-501 T stem cell therapy at the dose of 80 x 10EE6 cells per infusion, with up to 4 infusions separated by six weeks between doses (infusion at time 0, and then after week 6, 12, and 18). Study subjects are then followed at the treatment site at 24 weeks and 30 weeks on-study. The primary objective in the expansion cohort is to determine the feasibility and safety of the highest established safe dose of RAPA-501 (80 x 10EE6 cells per infusion) in patients with standard-risk ALS (as defining by study entry values of: SVC greater than or equal to 70% of predicted normal; time interval since first ALS symptom, 24 months or less; and ALSFRS-R score between 34 and 45). Secondary study objectives relate to assessing the potential efficacy of RAPA-501 therapy through monitoring of ALSFRS-R scores, SVC values, time to King's stage transition, and survival.
978 studies on the registry are indexed under Amyotrophic Lateral Sclerosis; 277 are open to participants now.
This study's planned enrollment of 41 is close to the median of 38 across 662 interventional studies indexed under Amyotrophic Lateral Sclerosis.
Browse Amyotrophic Lateral Sclerosis studies →Rapa Therapeutics LLC is the lead sponsor of 6 studies on the registry; 3 are open to participants now.
Counted across the registry records on this site, refreshed daily.
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.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
The US National Cancer Institute’s scale of how severe an adverse event is — any unwanted medical event during a study, such as a symptom, an illness or an abnormal test result, whether or not a treatment caused it. Whether it did is judged separately.
“Side effects of earlier treatment resolved to grade 1 or less” means they have settled to mild or gone.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
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.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
CTCAE grade
The US National Cancer Institute’s scale of how severe an adverse event is — any unwanted medical event during a study, such as a symptom, an illness or an abnormal test result, whether or not a treatment caused it. Whether it did is judged separately.
“Side effects of earlier treatment resolved to grade 1 or less” means they have settled to mild or gone.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
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.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Phase 2/3 Expansion Cohort, Single-agent RAPA-501 T stem cells 80 x 10EE6 cells per infusion (no host conditioning)
Biological: RAPA-501 Autologous T stem cells
Experimental: Phase 2/3 Expansion Cohort, Single-agent RAPA-501 T stem cells 80 x 10EE6 cells per infusion (no host conditioning)
Also known as: RAPA-501 cells
In the expansion cohort enrolling standard-risk pwALS, determine the feasibility and safety of the highest established safe dose of RAPA-501 (80 x 10^6 cells per infusion).
Time frame: Through 30 Weeks On-Study
Characterize immune system parameters pre- and post-therapy.
Specifically, relative to pretreatment patient peripheral blood values, determine whether study interventions: (a) increase circulating Th2 and TREG cells; (b) reduce circulating Th1 cells; (c) increase T cell expression of programmed death-1 (PD-1); and (d) reduce inflammatory cytokines IL-1-beta, IL-6, and TNF-alpha.
Time frame: Through 30 Weeks On-Study
Relative to pretreatment values, characterize the potential effect of RAPA-501 therapy on serum markers of neurodegeneration (neurofilament light, NfL).
Time frame: Through 30 Weeks On-Study
Relative to pretreatment values, characterize the potential effect of RAPA-501 therapy on pulmonary function, as measured by slow vital capacity measurements (SVC, percent of predicted normal).
Time frame: Through 30 Weeks On-Study
Relative to pretreatment values, characterize the potential effect of RAPA-501 therapy on hand grip strength using hand-held dynamometry.
Time frame: Through 30 Weeks On-Study
Started Jan 2025 (actual). Primary completion is estimated for Jul 2027, 29 months after the start.
Of 22 phase 2/3 interventional studies under Amyotrophic Lateral Sclerosis, half reached primary completion within 25 months of starting (the median), counting those still running; a quarter within 18 and three quarters within 109. This study's planned 29 months is above that.
Since we started tracking on Sep 25, 2026, the dates moved once, on Sep 29, 2026: primary completion Jul 2026 → Jul 2027 and completion Jun 2027 → Jul 2028.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Amyotrophic Lateral Sclerosis →
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