A Phase 1/2 interventional study of PBKR03 in Leukodystrophy, Globoid Cell, sponsored by Gemma Biotherapeutics. Suspended at 9 sites in 6 countries. Open to participants aged 1 Month to 9 Months. Per ClinicalTrials.gov, last updated 2026-06-30.
Sponsored by Gemma Biotherapeutics · Phase 1/2, Interventional, and Treatment
PBKR03 is a gene therapy for Krabbe Disease (Globoid cell leukodystrophy) intended to deliver a functional copy of the GALC gene to the brain and peripheral tissues. This study will evaluate the safety, tolerability and efficacy of this treatment by first evaluating two different doses in two different age groups, then confirming the optimal dose to be used for confirmation of safety and efficacy.
PBKR03 is an adeno-associated viral vector serotype Hu68 carrying the gene encoding for human galactosylceramidase, GALC, formulated as a solution for injection into the cisterna magna.
This is a global interventional, multicenter, single-arm, dose escalation, study of PBKR03 delivered as a one-time dose administered into the cisterna magna of subjects with early infantile Krabbe Disease.
The dose-ranging portion of the study will enroll independent dose escalation cohorts in two age groups of subjects with early infantile Krabbe disease:
Part 1 of the study will enroll a total of four cohorts, enrolled sequentially with separate age-based dose-escalation cohorts. Enrollment will initiate in Cohort 1. Following completion of Cohort 1, simultaneous enrollment in Cohort 2 and Cohort 3 will occur. Cohort 4 will follow completion of cohort 3.
The confirmatory cohort, Part 2, will enroll subjects with early infantile Krabbe Disease, aged >1 to \<9 months. These subjects will receive a dose chosen based on the data obtained in part 1 of the study This will be a 2-year study with a 3-year safety extension.
31 studies on the registry are indexed under Leukodystrophy, Globoid Cell; 8 are open to participants now.
This study's planned enrollment of 24 is below the median of 38 across 15 interventional studies indexed under Leukodystrophy, Globoid Cell.
Browse Leukodystrophy, Globoid Cell studies →Gemma Biotherapeutics is the lead sponsor of 3 studies on the registry; 1 is 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.
Symptomatic subjects must exhibit a minimum level of neurological and developmental function that indicates that they have the potential to benefit from treatment, at least with slowing or stabilization of their disease. In particular, the subject must demonstrate the following clinical features (when age-appropriate):
Exclusion Criteria:
Hematological abnormalities
Abnormal respiratory function
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.
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.
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.
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.
Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.
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.
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 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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Cohort 1: Subjects aged \>4 to \<9 months Drug: PBKR03 1.5 x 10\^11 GC/g\* Single dose of PBKR03, via intra cisterna magna Cohort 2: Subjects aged \>4 to \<9 months Drug: PBKR03 5.0 x 10\^11 GC/g\* Single dose of PBKR03, via intra cisterna magna Cohort 3: Subjects aged \>1 to \<4 months Drug: PBKR03 1.5 x 10\^11 GC/g\* Single dose of PBKR03, via intra cisterna magna Cohort 4: Subjects aged \>1 to \<4 months Drug: PBKR03 5.0 x 10\^11 GC/g\* Single dose of PBKR03, via intra cisterna magna \*GC/g: genome copiesy per gram of estimated brain weight
Biological: PBKR03
Cohort 5: Subjects aged \>1 to \<9 months Drug: PBKR03 Single dose of PBKR03, via intra cisterna magna Dose to be used for the confirmatory cohorts in Part 2 will be defined after a review of data from Part 1. \*GC/g: genome copiesy per gram of estimated brain weight
Biological: PBKR03
Single dose of PBKR03, via intra cisterna magna
Number of participants with treatment-related adverse events (AEs) and serious adverse events (SAEs) at Grade 3 or higher within 24 months of dosing
Assess the number of adverse events and serious adverse events at Grade 3 or higher as assessed by CTCAEv5.0
Time frame: Up to 5 years (multiple visits)
Change from baseline in nerve conduction and velocity in motor nerve conduction studies
NCS will measure velocity and amplitude in distal segments of the median, peroneal and tibial motor nerves to evaluate effects on peripheral nerve integrity.
Time frame: From baseline to 5 years (multiple visits)
Change from baseline in nerve conduction and velocity in sensory nerve conduction studies
NCS will measure velocity and amplitude in distal segments of the sural, radial and median sensory nerves to evaluate effects on peripheral nerve integrity
Time frame: From baseline to 5 years (multiple visits)
Number of Participants with Clinically Significant Laboratory Abnormalities as Measured Using Hematology, Chemistry and Coagulation Tests
Assess the number of participants with clinically significant laboratory changes including hematology, serum chemistry, and coagulation tests
Time frame: Up to 5 years (multiple visits)
Assess Humoral Response Against the Vector and Transgene in Serum
Assess serum antibody titers against AAVhu68 and against GALC following ICM administration of PBKR03
Time frame: Up to 5 years (multiple visits)
Assess Humoral Response Against the Vector and Transgene in CSF
Assess antibody titers in the cerebrospinal fluid against AAVhu68 and against GALC following ICM administration of PBKR03
Time frame: Up to 5 years (multiple visits)
Change from Baseline in Developmental Milestones as Assessed by the Bayley Scale of Infant and Toddler Development, Third Edition
Assess changes in the developmental age and the total number of developmental milestones using the Bayley Scale of Infant and Toddler Development, Third Edition instrument
Time frame: From baseline to 2 years (multiple visits)
Change from Baseline in Developmental Milestones as Assessed by the Vineland Adaptive Behavior Scale-II
Assess changes in the developmental age and the total number of developmental milestones using the Vineland Adaptive Behavior Scale-II instrument
Time frame: From baseline to 2 years (multiple visits)
Change in Biomarkers of GALC Activity in Blood
Assess change in biomarkers of GALC activity in blood when compared with baseline
Time frame: From baseline to 2 years (multiple visits)
Change in Biomarkers of GALC Activity in CSF
Assess change in biomarkers of GALC activity when compared with baseline
Time frame: From baseline to 2 years (multiple visits)
Change in Biomarkers of GALC Substrates in Blood
Assess change in concentration of GALC substrates in blood
Time frame: From baseline to 2 years (multiple visits)
Change in Biomarkers of GALC Substrates in CSF
Assess change in concentration of GALC in CSF when compared with baseline
Time frame: From baseline to 2 years (multiple visits)
Change in Concentration of Biomarker of Disease Progression in Plasma
Assess change in neurofilament light chain (NfL) concentration as a marker for neurodegeneration and disease progression in plasma
Time frame: From baseline to 2 years (multiple visits)
Change in Concentration of Biomarker of Disease Progression in CSF
Assess change in neurofilament light chain concentration (NfL) as a marker for neurodegeneration and disease progression in CSF
Time frame: From baseline to 2 years (multiple visits)
Change in Brain Anatomy as Assessed by MRI
Assess change in disease severity, volumetric MRI measures, brain diffusivity, and white matter lesions by MRI imaging
Time frame: From baseline to 2 years (multiple visits)
Change in Quality of Life Using Pediatric Quality of Life Scale
Assess change in quality of life as measured by Pediatric Quality of Life Scale (Peds QL)
Time frame: From baseline to 2 years (multiple visits)
Change in Quality of Life Using Pediatric Quality of Life Scales
Assess change in quality of life as measured by the Pediatric Quality of Life - Infant Scale (PedsQL-IS)
Time frame: From baseline to 2 years (multiple visits)
Change in Ventilator-Free Survival Compared with Natural History Data
Assess change compared with natural history data in ventilator-free survival and chronic ventilatory support.
Time frame: From baseline to 2 years (multiple visits)
Incidence of Feeding Tube Placement at or Before Month 24
Though speech and swallowing assessment, study participants will be evaluated to determine whether a feeding tube is warranted
Time frame: 24 months
Plan to share: No
Started Feb 2022 (actual). Primary completion is estimated for Jan 2027, 59 months after the start.
How these figures are worked out, and which studies are left out of them.
This study is suspended, as verified in Nov 2025. You cannot join it, but the record below documents what was studied.
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Leukodystrophy, Globoid Cell →
Gemma Biotherapeutics