A Phase 1/2 interventional study of Allogenic Human Islet Cells and Gastrin 17 in Diabetes Mellitus, Type 1, sponsored by City of Hope Medical Center. Recruiting at 1 site in United States. Open to participants aged 18 Years to 68 Years. Per ClinicalTrials.gov, last updated 2026-10-15.
Sponsored by City of Hope Medical Center · Phase 1/2, Interventional, and Treatment
This clinical study will evaluate the safety and effectiveness of Gastrin treatment with islet transplantation to help patients with difficult to control type 1 diabetes make insulin again and improve blood sugar control.
This study involves two investigational (experimental) products not yet approved by the U.S. Food and Drug Administration (FDA) as a treatment for any disease:
Islet cell transplantation involves transplanting the cells that make insulin from a pancreas of deceased organ donor to a patient with diabetes. Because there is a limited supply of donor islet cells available, this study is testing whether Gastrin injections can help make a fewer number of transplanted islets work better.
Gastrin is a natural gut hormone that is present in the pancreas during its development in the embryo but not after birth, and is believed to participate in the formation of the normal pancreas. Several studies have tried to use gastrin to help grow insulin making islet cells in laboratory experiments or after transplanting islets in laboratory animals. In early clinical trials, diabetic patients treated with gastrin and other growth factors required less insulin after 4 weeks of gastrin treatment and the effect lasted more than 12 weeks after stopping treatment, suggesting that gastrin may have increased the number of cells that make insulin.
This study will evaluate whether taking Gastrin injections following a single islet transplantation is safe, improves how well the islet transplant works and/or helps increase the number of insulin-making cells in the islets.
Qualified participants will receive treatment with a single islet transplant and two rounds of gastrin treatment (twice daily injections for 30 days) with transplant and again 6 months later. Study participants will also take anti-rejection medications (to prevent the body from rejecting the islet cells) and other medications to guard against infection and support their health and/or the health of the transplanted islets. Participants will need to return to City of Hope in Duarte, CA for frequent follow-up visits for one year after transplant.
3,754 studies on the registry are indexed under Diabetes Mellitus, Type 1; 600 are open to participants now.
This study's planned enrollment of 20 is below the median of 40 across 2,820 interventional studies indexed under Diabetes Mellitus, Type 1.
Browse Diabetes Mellitus, Type 1 studies →City of Hope Medical Center is the lead sponsor of 677 studies on the registry; 181 are open to participants now.
Of its 31 completed or terminated interventional studies of FDA-regulated products, 12 (39%) have results posted.
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.
Unstable blood glucose characterized by:
Frequent hypoglycemia (blood glucose less than or equal to 54 mg/dl more than once per week)
-and/or- Hypoglycemia unawareness (Clarke score of 4 or more).
-and/or- One or more severe hypoglycemic episodes in 12 months preceding enrollment
-and/or- Erratic blood glucose levels that interfere with daily activities
-and/or- One or more hospital visits for diabetic ketoacidosis in the 12 months preceding enrollment
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 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.
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.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
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.
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.
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.
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
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.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
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.
Able to have children. For women this usually means from the first period until menopause, unless permanently unable to through surgery; for men, unless permanently sterile. Read who the line is about — participants, women, men, or their partners.
Criteria about it usually ask for contraception during the study and for a time after it.
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.
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.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
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.
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.
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.
LVEF (left ventricular ejection fraction)
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
INR, PT and aPTT (clotting tests)
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
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.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Live vaccines
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Reproductive potential
Able to have children. For women this usually means from the first period until menopause, unless permanently unable to through surgery; for men, unless permanently sterile. Read who the line is about — participants, women, men, or their partners.
Criteria about it usually ask 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.
Biological: Allogenic Human Islet Cells · Drug: Gastrin 17
islet cells transplanted into the portal vein in the liver
Gastrin-17 (or GAST-17) - a gut hormone injected under the skin twice daily for 30 days soon after islet transplant and again 6 months later. Also, anti-rejection medications (to prevent the body from rejecting the islet cells) and other medications to guard against infection and support participant health and/or the health of the transplanted islets.
Proportion of subjects who are insulin independent, free from severe hypoglycemia and have HbA1c less than or equal to 6.5% ("complete response")
Time frame: 1 year post transplant (6 months after second course of Gastrin)
Proportion of subjects who are free of severe hypoglycemic episodes (SHE) and have a HbA1c less than or equal to 7.0% ("partial response").
Time frame: At Month 1, Month 2.5, and Month 6 post start of each Gastrin course
Reduction/elimination of hypoglycemia
Time frame: At Month 1, Month 2.5, and Month 6 post start of each Gastrin course
Reduction in daily insulin use
Time frame: At Month 1, Month 2.5, and Month 6 post start of each Gastrin course
Reduction of daily insulin use per 100,000 IEQ transplanted
Time frame: At Month 1, Month 2.5, and Month 6 post start of each Gastrin course
C-peptide/insulin secretion response to glucose/arginine stimulation and other metabolic studies.
Time frame: At Month 1, Month 2.5, and Month 6 post start of each Gastrin course
Incidence of treatment-related adverse events
Time frame: At Month 1, Month 2.5, and Month 6 post start of each Gastrin course
Incidence of a change in immunosuppression drug regimen
Time frame: At Month 1, Month 2.5, and Month 6 post start of each Gastrin course
The incidence of immune sensitization defined by presence of anti-HLA antibodies absent prior to transplant
Time frame: At Month 1, Month 2.5, and Month 6 post start of each Gastrin course
Incidence of discontinuation of immunosuppression
Time frame: At Month 1, Month 2.5, and Month 6 post start of each Gastrin course
Incidence of change or early discontinuation of Gastrin treatment
Time frame: At Month 1, Month 2.5, and Month 6 post start of each Gastrin course
Incidence of change or early discontinuation of sitagliptin/esomeprazole supportive therapy
Time frame: At Month 1, Month 2.5, and Month 6 post start of each Gastrin course
Improvement in glucose time in range during continuous glucose monitoring
Time frame: At Month 1, Month 2.5, and Month 6 post start of each Gastrin course
Improvement in Personal Glycemic State (PGS) score calculated from continuous glucose monitoring
Time frame: At Month 1, Month 2.5, and Month 6 post start of each Gastrin course
Started May 2019 (actual). Primary completion is estimated for Aug 2028, 110 months after the start.
Of 44 phase 1/2 interventional studies under Diabetes Mellitus, Type 1, half reached primary completion within 57 months of starting (the median), counting those still running; a quarter within 31 and three quarters within 93. This study's planned 110 months is above that.
Start moved once since we started tracking on Sep 25, 2026: Jul 2019 → May 2019, on Oct 15, 2026.
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 ↗
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.