Lentiviral Vector Gene Therapy - The GuardOne Trial of AVR-RD-02 for Subjects With Type 1 Gaucher Disease

• Status: Recruiting
• Trial end date: 2023-12-01
• Target enrollment: 0
• Participant gender: All

Summary

This is a multinational, open-label study to assess the safety and efficacy of AVR-RD-02 in approximately 8 to 16 subjects (male or female) who are ≥18 and ≤45 years of age and postpubertal at Screening with a confirmed diagnosis of Type 1 Gaucher disease (based on clinical phenotype, genotyping, and deficient GCase enzyme activity in whole blood).

• Phase: Phase 1/Phase 2
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: AvroBio

Criteria

INCLUSION CRITERIA for all Enrolled (Switch-stable and Treatment-naïve) Subjects:

1. Subject is ≥18 and ≤45 years old and postpubertal

2. Subject has a confirmed diagnosis of Type 1 Gaucher disease based on genotyping, deficient GCase enzyme in whole blood, and clinical phenotype at Screening.

a. For switch-stable subjects, documentation of intracellular leukocyte GCase enzyme activity prior to having been started on ERT is required. If GCase levels prior to ERT are not available, trough GCase enzyme activity in whole blood at Screening is required.

3. Female subjects of reproductive potential.

a. Female subjects will be counseled regarding the risks, benefits, limitations, and alternatives associated with female fertility preservation. Oocyte harvesting and cryopreservation will be offered prior to conditioning treatment. Female subjects must agree to refrain from donating eggs after undergoing conditioning treatment.

4. Male subjects must be willing to refrain from donating sperm at any time after receiving conditioning therapy. For subjects planning on (or for whom there is a possibility of) fathering children in the future, sperm banking before administration of the conditioning regimen will be recommended.

5. All subjects who have not undergone successful surgical sterilization (ie, vasectomy, hysterectomy, bilateral tubal ligation, or bilateral oophorectomy) must agree to remain sexually abstinent or use two effective methods of contraception while sexually active from the day of conditioning administration until 52 weeks post-transplantation (ie, the Week 52 study visit). Two methods of contraception are required even with documented medical assessment of surgical success of sterilization.

1. For male subjects and for male spouses/partners of female subjects, condoms are an acceptable method of barrier contraception.

2. For female subjects and for female spouses/partners of male subjects, acceptable methods of barrier contraception include diaphragm, cervical cap, or contraceptive sponge

6. Male and female subjects must agree to refrain from donating sperm and eggs, respectively, after undergoing conditioning.

7. Subject must be willing to refrain from donating blood, organs, tissues, or cells for transplantation any time after AVR-RD-02 treatment.

8. Subject must be willing and able to provide written informed consent for the study in accordance with applicable regulations and guidelines and to comply with all study visits and procedures, including the use of any data collection device(s) that may be used to directly record subject data.

Additional Inclusion Criteria for Switch-stable Subjects (in addition to criteria 1-8 above):

9. Subject has undergone ERT ≥15 U/kg and ≤60 U/kg every other week (or equivalent; ie, any combination of infusions resulting in a total monthly ERT dose of >30 U/kg and <120 U/kg) for ≥24 consecutive months for Gaucher disease at the time of Screening.

10. Subject has normal or near-normal hematologic values (Hemogloblin concentration and Platelet count) at Screening as one or more of the following:

1. Hemoglobin concentration ≥10 g/dL

2. Platelet count ≥80x10^9

11. Subject has stable Gaucher disease during the 6 months immediately preceding Screening defined by stable hemoglobin concentration and platelet count based on documented lab results:

1. Stable hemoglobin concentration (ie, within a range of ±12 g/dL of the Screening value) based on documented historical clinical laboratory results and

2. Stable platelet count (within ±20% of the Screening value) based on documented historical clinical laboratory results

12. Subject has not received SRT for Gaucher disease during the 12 months immediately preceding Screening.

Additional Inclusion Criteria for Treatment-naïve Subjects (in addition to inclusion criteria 1 through 8, above, treatment-naïve subjects must meet the following inclusion criteria for participation in this study):

13. Subject has not received ERT or SRT for Gaucher disease within 12 months of Screening.

14. Subject has a hemoglobin level ≤2 g/dL below the lower limit of normal (LLN) for age and sex at Screening and at least one of the following at Screening:

1. Platelet count <120 X 10^9/L

2. Enlarged liver by palpation, confirmed on abdominal MRI

3. Moderate splenomegaly by palpation, confirmed on abdominal MRI

EXCLUSION CRITERIA:

1. Subject has Type 2 or 3 Gaucher disease, is suspected of having Type 3 Gaucher disease, has severe neurological signs and symptoms, defined as complete ocular paralysis, overt myoclonus or history of seizures, characteristic of neuronopathic Gaucher disease, or has a tremor, peripheral neuropathy or symptoms of Parkinson's disease.

2. Subject has any one of the following:

1. Hemoglobin value <9.0 g/dL, or

2. Platelet count <70 X 109/L, or

3. Spleen volume >10 X normal, or

4. Pulmonary hypertension

3. Subject has undergone a partial or total splenectomy or is scheduled to undergo a partial or total splenectomy.

4. Subject has experienced a prior anaphylactic or anaphylactoid reaction (of any severity) to ERT.

5. Treatment-naïve subject has clinically significant anti-GCase antibodies.

6. Subject has a contraindication to ERT, in the opinion of the Investigator.

7. Subject has a contraindication to HSC transplantation, in the opinion of the Investigator.

8. Subject presents with iron, folic acid and/or vitamin B12 deficiency sustained anemia during Screening.

9. Subject has idiopathic thrombocytopenic purpura (ITP), thrombotic thrombocytopenic purpura (TTP), thrombocytopenia, anemia, hepatomegaly, splenomegaly, and/or osteoporosis, unrelated to Gaucher disease.

10. Subject has a clinical co-morbidity such as neurologic, cardiovascular, pulmonary, hepatic, gastrointestinal, renal, hematologic, endocrine, metabolic, genetic, immunologic, neoplastic, or psychiatric disease, other medical condition(s), or intercurrent illnesses that may confound the study results or, in the opinion of the Investigator, may preclude participation in the study.

11. Subject is a pregnant and/or lactating female.

12. Subject is unable to understand the nature, scope, and possible consequences of the study.

13. Subject has diabetes mellitus (Type 1 or Type 2).

14. Subject has active, progressive bone necrosis.

15. Subject has an active chronic infection during the Screening, Baseline, or Pre-transplant Period of the study.

16. Subject has an active uncontrolled acute bacterial, viral, fungal, parasitic, or prion-associated infection during the Screening, Baseline, or Pre-transplant Period of the study.

17. Subject has a history of (or current) tuberculosis.

18. Subject tests positive for hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV, Type 1 or 2), human T-cell lymphotropic virus (HTLV)-1, HTLV-2, and/or syphilis on Venereal Disease Research Laboratory (VDRL) test, chemiluminescent microplate immunoassay (CMIA), or enzyme immunosorbent assay (EIA) at Screening.

19. Subject has a prior history of (or current) cancer or precancerous lesion or has a known genetic predisposition to cancer. The one exception is a prior history of resected squamous cell carcinoma.

20. Subject has any other medical condition that predisposes him/her to (or conveys increased risk of) malignancy, in the opinion of the Investigator.

21. Subject has a history of alcohol or illicit drug abuse, according to the Investigator's judgment.

22. Subject has undergone, or is scheduled to undergo, bone marrow transplant, HSC transplant, and/or solid organ transplant. NOTE: Subjects who are otherwise eligible for the study but are scheduled for bone marrow or HSC transplant to treat Type 1 Gaucher disease may be enrolled in the study (instead of receiving an allogeneic transplant) and undergo gene therapy with AVR-RD-02.

23. Subject has white blood cell count (WBC) <3.0x109/L and/or uncorrected bleeding disorder from enrollment (ie, signing of informed consent at Screening) through the Transplant Period of the study (ie, the day of AVR-RD-02 infusion).

24. Subject has clinically significant immunosuppressive disease or condition, in the opinion of the Investigator, at Screening.

25. Subject is on (or requires treatment with) cytotoxic or immunosuppressive agents from 60 days prior to signing informed consent at Screening (ie, study enrollment) through the Week 52 study visit; the one exception is treatment with cytotoxic or immunosuppressive agents required per protocol for stem cell transplant.

26. Subject is on (or requires treatment with) red blood cell (RBC) growth factor (eg, erythropoietin) from 6 months prior to enrollment (ie, signing of informed consent at Screening) through the Week 52 study visit.

27. Subject has any condition that makes it impossible to perform MRI studies.

28. Subject has medical conditions(s) and/or is receiving medication(s) that would contraindicate ability to undergo mobilization (including contraindication to G-CSF and/or plerixafor), apheresis, or conditioning.

29. Busulfan is contraindicated for the subject.

30. Subject has previously received treatment with AVR-RD-02 or any other gene therapy.

31. Subject is participating in (or plans to participate in) any other investigational drug trial, or plans to be exposed to any other investigational agent, device and/or procedure, from 30 days prior to enrollment (ie, signing of informed consent at Screening) through study completion.