A Phase 1 interventional study of Dopacell and Immunosuppressive Regimen in Parkinson Disease (PD), sponsored by Royan Institute. Recruiting at 3 sites in Iran. Open to participants aged 30 Years to 70 Years. Per ClinicalTrials.gov, last updated 2026-06-18.
Sponsored by Royan Institute · Phase 1, Interventional, and Treatment
Dopason is a phase I, open-label, multicenter, single-arm clinical trial designed to evaluate the safety and feasibility of intraputaminal transplantation of human embryonic stem cell-derived dopaminergic progenitor cells (DopaCells) in patients with moderately severe Parkinson's disease.
During this trial phase, a total of six participants will be included and distributed between two clinical centers. Each participant will undergo one standardized surgical procedure consisting of bilateral stereotactic intraputaminal transplantation of approximately 10 × 10⁶ cells in total (about 5 × 10⁶ cells per putamen), aiming to achieve an estimated survival of 200,000 neurons. All procedures will be performed using the same surgical delivery system and an almost identical operative protocol across both sites to ensure procedural consistency. After transplantation, patients will receive immunosuppressive therapy for a duration of one year and will be systematically followed for study outcomes for at least 12 months.
4,573 studies on the registry are indexed under Parkinson Disease; 1,086 are open to participants now.
This study's planned enrollment of 6 is below the median of 40 across 3,353 interventional studies indexed under Parkinson Disease.
Browse Parkinson Disease studies →Royan Institute is the lead sponsor of 94 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.
The performance of different organs based on laboratory evaluations:
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.
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.
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.
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.
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.
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.
Short tests of memory and thinking, each scored out of 30. Lower scores suggest more difficulty; criteria give a range, either to include people with memory problems or to leave them out.
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.
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 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.
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 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.
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.
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.
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.
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.
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.
MMSE and MoCA
Short tests of memory and thinking, each scored out of 30. Lower scores suggest more difficulty; criteria give a range, either to include people with memory problems or to leave them out.
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.
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 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.
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.
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.
Experimental: DopaCell Biological: DopaCell, 5 million cells per putamen Immunosuppressive Regimen: Basiliximab, Tacrolimus, Prednisolone Device: Customized microinjection device
Biological: Dopacell · Drug: Immunosuppressive Regimen · Device: Customized microinjection device
DopaCells are dopamine-producing progenitor cells generated from human embryonic stem cells through differentiation under GMP-compliant conditions.
Basiliximab, Tacrolimus, Prednisolone
For intraputaminal delivery of DopaCell
Safety
Incidence and severity of treatment-emergent adverse events (TEAEs)
Time frame: Baseline to 12 Months Post-Transplant
Safety
Evidence of any post-transplantation anatomical changes at the transplant site suggestive of tumor formation, as assessed by MRI imaging.
Time frame: Baseline to 12 Months Post-Transplant
Feasibility
Successful completion of a single-session intraputaminal transplantation with of the intended cell dose
Time frame: Baseline to 12 Months Post-Transplant
Efficacy
Changes in the duration of OFF and ON periods following intracerebral DopaCells transplantation as assessed by the Hauser diary
Time frame: Baseline to 12 Months Post-Transplant
Efficacy
Changes in the Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part III score from baseline following intracerebral DopaCells transplantation during ON and OFF periods ( MDS-UPDRS Part III ranges from 0 to 132, where higher scores indicate worse motor impairment.)
Time frame: Baseline to 12 Months Post-Transplant
Efficacy
Graft survival following intracerebral DopaCells transplantation based on TRODAT SPECT imaging findings.
Time frame: Baseline to 12 Months Post-Transplant
Continuous Safety
Continuous Safety: The number and severity of treatment-emergent adverse events
Time frame: Baseline to 60 Months Post-Transplant
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