ClinicalTrials.gg
TerminatedNCT04525352Updated Jul 13, 2022

A Trial to Evaluate Safety and Efficacy of RP-L401-0120 in Subjects With Infantile Malignant Osteopetrosis

A Phase 1 interventional study of RP-L401 in Infantile Malignant Osteopetrosis, sponsored by Rocket Pharmaceuticals Inc.. Terminated at 1 site in United States. Open to participants aged 1 Month and older. Per ClinicalTrials.gov, last updated 2022-07-13.

Sponsored by Rocket Pharmaceuticals Inc. · Phase 1, Interventional, and Treatment

Why this study was terminated
Study discontinued due to feasibility.

From the registry’s dates

  • Primary completion was May 2021, 5 years 5 months ago, and no results have been posted to the registry.
Phase
Phase 1
Study type
Interventional
Enrollment
1
Allocation
Not applicable
Ages
1 Month and older
Sex
All
01

Study summary

The primary objective of this Phase 1 study is to evaluate the therapeutic safety and feasibility of the investigational product (IP), RP-L401.

Read the detailed description

This is a non-randomized Phase 1 study to evaluate the preliminary safety and efficacy of hematopoietic gene therapy consisting of autologous CD34+ enriched hematopoietic cells transduced with the lentiviral vector (LV) carrying the human TCIRG1 transgene (RP-L401) in pediatric patients with IMO. Following myeloablative conditioning patients will receive an infusion of the genetically modified hematopoietic stem and progenitor cells (HSPCs).

02

Conditions studied

  • Infantile Malignant Osteopetrosis

Keywords

  • Impaired bone resorption
  • Deficient osteoclast development
  • Autosomal Recessive Disorder
  • Musculoskeletal Diseases
  • Bone Diseases
  • Hypocalcemia
  • Bone marrow failure
03

In context

Musculoskeletal Diseases

752 studies on the registry are indexed under Musculoskeletal Diseases; 164 are open to participants now.

This study's enrollment of 1 is below the median of 76 across 518 interventional studies indexed under Musculoskeletal Diseases.

Browse Musculoskeletal Diseases studies →

Lead sponsor

Rocket Pharmaceuticals Inc. is the lead sponsor of 19 studies on the registry; 7 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
1 Month and older
Sexes eligible
All
Accepts healthy volunteers
No

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.

Inclusion criteria

  1. A confirmed diagnosis of IMO with documented TCIRG1 mutation.
  2. Age at least 1 month with minimum weight of 4 kg
  3. Absence of debilitating hydrocephalus (defined as hydrocephalus at v5.0 Grade 3 or higher persisting despite shunt or similar procedural intervention).
  4. Lansky Play Scale of at least 60%
  5. Preserved hepatic function (/ALT ≤3.0 ; ≤1.5 ULN; to minimize potential for excessive toxicity from busulfan conditioning)
  6. No concomitant medical or other conditions that would represent a to hematopoietic stem cell transplant.
  7. of ≥500/mm3 and count of ≥25,000/mm3
  8. No prior allogeneic or other hematopoietic stem cell transplant.
  9. Availability of a non-autologous rescue (back-up) hematopoietic stem cell donor/source

Exclusion criteria

Exclusion Criteria:

  1. Availability of medically-feasible HLA-matched sibling donor for HSCT.
  2. Any medical or other for either apheresis or autologous transplant as determined by the Investigator.
  3. Participation in another clinical trial with an drug within 14 days before the signature. Participation in observational studies is allowed.
  4. Active hematologic or solid organ , not including non-melanoma skin cancer or another carcinoma in situ.
  5. Uncontrolled seizure disorder.
  6. Renal dysfunction as defined by a \<30 mL/min/1.73m2 or dialysis dependence.
  7. Serious infections with persistent bloodstream pathogens at time of trial entry
  8. Pulmonary dysfunction as defined by either:

    • Need for supplemental oxygen during the prior 2 weeks (in absence of acute infection) or
    • Oxygen saturation (by pulse oximetry) \<90% resulting from pulmonary conditions (intermittent hypoxia secondary to IMO-related choanal atresia will not be considered exclusionary)
Terms in these criteria, in plain language(12)

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.

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.

1
Mild.
2
Moderate.
3
Severe.
4
Life-threatening.
5
Death due to the event.

“Side effects of earlier treatment resolved to grade 1 or less” means they have settled to mild or gone.

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.

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.

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.

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.

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.

Absolute neutrophil count (ANC)

The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.

It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.

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.

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.

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.

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.

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.

05

Study design

Phase
Phase 1
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
1 participant (actual)

Study arms

  • Experimental
    Experimental - RP-L401

    RP-L401 is a gene therapy product containing autologous genetically modified CD34+ hematopoietic cells transduced with lentiviral vector carrying the TCIRG1 transgene

    Biological: RP-L401

Interventions

  • BiologicalRP-L401

    CD34+ enriched hematopoietic stem cells from pediatric subjects with infantile malignant osteopetrosis transduced ex vivo with lentiviral vector carrying the TCIRG1 transgene

06

What researchers measure

Primary outcomes

  1. Number of participants with treatment-related adverse events as assessed by the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) v5.0

    Evaluation of safety associated with treatment with RP-L401

    Time frame: 2 years

Secondary outcomes

  1. Assessment of vector copy number (VCN) after infusion of RP-L401

    Evaluation of the presence of gene-modified blood and bone marrow cells post infusion via blood and bone marrow assessments

    Time frame: 2 years

  2. Assessment of endocrine and metabolic status after infusion of RP-L401

    Evaluation of normalization of serum calcium levels via a blood assessment

    Time frame: 2 years

  3. Assessment of blood counts after infusion of RP-L401

    Evaluation of the stabilization or improvement in blood counts as assessed by NCI CTACE

    Time frame: 2 years

  4. Assessment of bone abnormalities after infusion of RP-L401

    Evaluation of the qualitative improvement in bone formation via x-ray studies

    Time frame: 2 years

  5. Assessment of auditory status after infusion of RP-L401

    Evaluation of the stabilization or improvement in hearing loss via auditory tests

    Time frame: 2 years

  6. Assessment of ophthalmology status after infusion of RP-L401

    Evaluation of optical abnormalities via visual assessments of the eye

    Time frame: 2 years

  7. Assessment of hepatosplenomegaly after infusion of RP-L401

    Evaluation of hepatosplenomegaly improvement via abdominal ultrasound

    Time frame: 2 years

  8. Assessment of head, mouth and gum abnormalities

    Photographic documentation of head, mouth and gums to assess disease stabilization, progression or improvement

    Time frame: 2 years

07

Study locations

1 site
  • University of California, Los Angeles
    Los Angeles, California 90095, United States
08

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reached

Ran from Nov 2020 to primary completion in May 2021, 6 months.

How these figures are worked out, and which studies are left out of them.

Registered
Aug 11, 2020
First posted
Aug 25, 2020
StartActual
Nov 19, 2020
Primary completionActual
May 21, 2021
CompletionActual
May 21, 2021
Last update
Jul 13, 2022
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Jul 13, 2022, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT04525352
Lead sponsor
Rocket Pharmaceuticals Inc.
Collaborators
California Institute for Regenerative Medicine (CIRM)
Responsible party
Sponsor
First posted
Aug 25, 2020
Start date
Nov 19, 2020
Primary completion
May 21, 2021
Completion
May 21, 2021
Last update
Jul 13, 2022

Study contacts

Donald B Kohn, MD
principal investigator · University of California, Los Angeles

Oversight

Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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This study is terminated, as verified in Jul 2022. You cannot join it, but the record below documents what was studied.

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