Pompe Disease (Late-onset)Phase 1/2FORTISNCT04174105

Gene Transfer Study in Patients With Late Onset Pompe Disease

A Phase 1/2 study testing zocaglusagene nuzaparvovec in people with Pompe Disease (Late-onset), run by Astellas Gene Therapies at 4 sites in 2 countries.

Active, not recruiting

Under way, not looking for participants. Everyone needed has enrolled. The study is still running.

Official record

Search all trials

Trial summary

This is a phase 1/2 open-label, ascending dose, multicenter clinical study to evaluate the safety and efficacy of AT845 in adult (aged ≥ 18 years) subjects, ambulatory or nonambulatory, with Late Onset Pompe Disease (LOPD). Read more about this study

Who is it for?: Ages 18 to 80 years
Conditions the study is for: Pompe Disease (Late-onset)
What is being tested?: zocaglusagene nuzaparvovec
Type of treatment: Injection or infusion
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 11 participants
Where: 4 sitesin 2 countries
Study dates: 27 Oct 2020to 28 Feb 2035
Phase: Phase 1/2
Are there results?: Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 18 to 80 years
All sexes
No healthy volunteers
Adult, Older adult

Who may be able to join

Participant is aged ≥ 18 years.
Participant has a documented clinical diagnosis of Pompe disease by genetic testing.
Participant has received enzyme replacement therapy (ERT) with rhGAA for the previous ≥ 2 years.
Participant has been on a stable standard dose (at least 20 mg/kg every 2 weeks) of ERT with rhGAA for at least the previous 6 months.
Participant or legally authorized representative(s) (LAR) (if applicable) provides written informed consent.
Participant and LAR(s) are willing and able to comply with study visits and study procedures.

Show all 9Show fewer

Participant must agree to refrain from blood or blood products donation and sperm or egg donation from the time of AT845 administration until the later of 90 days or 3 consecutive negative viral shedding samples
Participants enrolled in previous protocol versions 1 through 9: Participant has upright FVC ≥ 30% of predicted normal value. Participants enrolled starting with protocol version 10 and subsequent amendments: Participant has upright FVC ≥ 30% and ≤ 85% of predicted normal value.
Participants enrolled starting with protocol version 10 and subsequent amendments: Participant who is able to ambulate ≥ 40 m without stopping and without the use of an assistive device. The use of an assistive device for community ambulation is acceptable. (Participants enrolled under previous protocol versions 1 through 9 will not be excluded if they do not meet this criterion during Rescreening visit).

Who cannot join

Participant is currently participating in an interventional study or has received gene or cell therapy.
Participant tests positive for AAV8 antibodies with titers >1:20 neutralizing.
Participant has received immune-modulating agents within 90 days before dosing (use of inhaled corticosteroids is allowed); use of other concomitant medications to manage chronic conditions must have been stable for at least 30 days before dosing. Concomitant medications that may predispose the participant to peripheral neuropathy will be evaluated.
Participant has any clinically significant laboratory values (other than those directly associated with LOPD [e.g., GAA, serum creatine kinase (CK)]) that would preclude participation in the study.
Participant has serological or viral load evidence of HIV-1 or HIV-2.
Participant has received drugs for treatment of myopathy or neuropathy with immunosuppressive therapy (e.g., corticosteroids, cyclosporine, tacrolimus, methotrexate, cyclophosphamide, IV immunoglobulin, rituximab) within 3 months prior to starting the study

Show all 29Show fewer

Participant has a high risk for a severe allergic reaction to rhGAA (ie, previous moderate to severe anaphylactic reaction to alglucosidase alfa or and/or a history of sustained high immunoglobulin G [IgG] antibody titers to alglucosidase alfa that suggests a high risk for an allergic reaction to ERT).
Participant has a history of hypersensitivity to β2 agonist drugs such as albuterol, levalbuterol, bitolterol, pirbuterol, terbutaline, salmeterol, which contraindicates pulmonary function testing.
Participant has an active viral infection based on clinical observation.
Participant has a history of or concurrent medical condition other than Pompe disease that could jeopardize safety of the participant or impact study results.
Participant has a history of, or currently has, a clinically important cardiac condition, such as an echocardiogram (ECHO) with ejection fraction below 40% or has symptoms or signs of cardiomyopathy that precludes enrollment.
Participant has a contraindication to study drug or to corticosteroids, or has demonstrated hypersensitivity to any of the components of the study drug.
Participant tests positive for GAA antibodies with titers > 1:50,000 total
Participant has a history of hypersensitivity to MRI contrast agents including gadolinium.
Participant has a known hypersensitivity to local anesthetics such as lidocaine.
Participant has a bleeding diathesis, e.g., due to anti-coagulation or anti-platelet treatments.
Participant has a concurrent medical condition (including uncontrolled diabetes, alcohol use disorder, certain autoimmune conditions, Lyme disease, active malignancy requiring chemotherapy and/or radiation, uremic nephropathy, known exposure to heavy metals) commonly associated with peripheral neuropathy. Other concurrent medical conditions that may predispose to peripheral neuropathy will be evaluated and action taken on a case-by-case basis, following discussion between the Investigator and Medical Monitor.
Participant who is unwilling to withdraw from ERT.
Participant has an active symptomatic large fiber peripheral neuropathy diagnosed by a neurologist at a screening visit.
Age-related sensory changes on NCS without symptoms or mononeuropathy (refers to focal involvement of a single nerve, usually due to a local cause such as trauma, compression or entrapment) will not be excluded.
Participant has clinically significant underlying liver disease at Screening, or has any of the following:
Alanine Aminotransferase (ALT) > 2 × upper limit of normal (ULN)
Aspartate aminotransferase (AST) > 2 × ULN
Total bilirubin > 1.5 × ULN
Alkaline phosphatase (ALP) > 2 × ULN
ALT and AST are often higher than the normal range in Pompe disease patients. Participants whose liver laboratory tests fall outside the above ranges may be retested and, if the eligibility criteria are met on retesting, may be enrolled after confirmation by the Medical Monitor.
In addition, participants with abnormal laboratory results related to confirmed benign liver conditions including Gilbert's syndrome (defined by asymptomatic unconjugated hyperbilirubinemia [17 to 70 µmol/L or 1 to 4 mg/dL]) and asymptomatic gallstones, will be considered eligible for the study notwithstanding their abnormal laboratory results and may be enrolled.
Participant is currently on antiviral therapy for hepatitis B or C, or chronic/active hepatitis B or active hepatitis C evidenced by hepatitis B surface antigen (HBsAg), hepatitis B core antibody (HBcAb), hepatitis B virus (HBV)-DNA positivity or hepatitis C virus (HCV)-RNA viral load positivity, respectively.
Negative viral load assays in 2 samples, collected at least 6 months apart, will be required to be considered negative. Both natural clearers and those who have cleared HCV on antiviral therapy are eligible. Participant has an active viral infection based on clinical observation.

Trial locations and contacts

4 sites in 2 countries.

Country

City, postcode or hospital

4 sites in 2 countries

United States3 sites

University of California Irvine, Department of Neurology
Orange, California, 92868
Stanford University
Palo Alto, California, 94304
University of Utah, Division of Medical Genetics
Salt Lake City, Utah, 84108

Other trials in United States

United Kingdom1 site

Newcastle Upon Tyne Hospitals Foundation Trust Clinical Research Facility
Newcastle upon Tyne, NE1 4LP

Other trials in United Kingdom

About this study

Official title: A Phase 1/2, Open-Label, Ascending-Dose Clinical Study to Evaluate the Safety and Preliminary Efficacy of AT845, an AAV8-Delivered Gene Transfer Therapy in Patients With Late Onset Pompe Disease

Read the detailed description

This study (FORTIS) will evaluate the safety and efficacy of an investigational gene replacement therapy, AT845, in adult subjects with LOPD. Subjects will receive a single dose of AT845 delivered via intravenous (IV) infusion.

Up to 3 nominal dose levels of AT845 are planned to be evaluated in this study. A single AT845 administration via IV infusion is planned for each subject. The initial dosing cohort received a single dose of 3x10^13 vg/kg of AT845. The second dose cohort will receive a single dose of 6×10^13 vg/kg. The third dose cohort will receive a single dose of 1×10^14 vg/kg. Dose escalation between cohorts will be based on evaluations of safety and in consultation with the independent DMC.

There will be a core observation period of 48 weeks with scheduled visits and assessments. Following the conclusion of the core observation period, subjects will be seen every 6 months for a safety follow-up visit for up to 10 years postdose.

Conditions: Pompe Disease (Late-onset)
Being tested: zocaglusagene nuzaparvovec
Keywords: LOPD
Medical subject headings: Glycogen Storage Disease Type II

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

zocaglusagene nuzaparvovecGenetic
Also called AT845
AT845 is an AAV8 vector delivering a functional copy of the human GAA gene, under the control of a muscle-specific promoter

Study groups in NCT04174105
Study group	Role	What they receive
Initial Dose Cohort	Experimental	3x10^13 vg/kg of AT845 administered via intravenous infusion Receives: Genetic: zocaglusagene nuzaparvovec
Second Dose Cohort	Experimental	6x10^13 vg/kg of AT845 administered via intravenous infusion Receives: Genetic: zocaglusagene nuzaparvovec
Third Dose Cohort	Experimental	1x10^14 vg/kg of AT845 administered via intravenous infusion Receives: Genetic: zocaglusagene nuzaparvovec

What is being measured

The primary outcome is the main question the study is designed to answer.

Safety and Tolerability over time
Frequency of adverse events (AEs), serious adverse events (SAEs), and changes from baseline in relevant clinical laboratory tests
Measured: Up to month 120
GAA enzymatic activity
Change from baseline in GAA enzymatic activity in muscle biopsies at week 12
Measured: Baseline and Week 12
GAA protein expression
Change from baseline in GAA protein expression in muscle biopsies at week 12.
Measured: Baseline and Week 12

Secondary outcomes (11)

Vector Copy Number
Change from baseline in vector copy number (VCN) in muscle biopsies at week 12
Measured: Baseline and Week 12
Thigh Fat Fraction
Change from baseline in thigh fat fraction by MRI
Measured: Baseline and Month 18
6-Minute Walk Test (for ambulatory patients)
Change from baseline in the distance walked in the 6 minute walk test (6MWT), which is a standardized assessment of how far an individual can walk on a hard, flat surface in a period of 6 minutes
Measured: Baseline, Week 24 and Week 48
Percentage Predicted for 6-Minute Walk Test (for ambulatory patients)
Change from baseline in percentage predicted for 6MWT, which is a standardized assessment of how far an individual can walk on a hard, flat surface in a period of 6 minutes
Measured: Baseline, Week 24 and Week 48
Forced Vital Capacity (FVC)
Change from baseline in percentage of predicted FVC measured by pulmonary function testing
Measured: Baseline, Week 24 and Week 48
Maximum Inspiratory Pressure (MIP)
Change from baseline in MIP measured by pulmonary function testing
Measured: Baseline, Week 24 and Week 48
Maximum Expiratory Pressure (MEP)
Change from baseline in MEP measured by pulmonary function testing
Measured: Baseline, Week 24 and Week 48
The Gait, Stairs, Gower Maneuver, Chair (GSGC)
The GSGC is a composite test that evaluates both the time to perform different motor activities and qualitatively measures motor function.
Measured: Baseline, Week 24 and Week 48
Rasch-built Pompe-specific Activity (R-PAct) scale
Change from baseline in the R-PAct scale, which was developed to measure Pompe patients' ability carry out daily life activities and social participation
Measured: Baseline and Week 48
EuroQol 5 Dimensions 5 Levels (EQ-5D-5L) Questionnaire
Change from baseline in health profiles and overall health status as assessed by the EQ-5D-5L
Measured: Baseline and Week 48
Patient-Reported Outcomes Measurement Information System (PROMIS)
Change from baseline in scores of PROMIS short forms for fatigue, physical function, social participation and sleep disturbance
Measured: Baseline and Week 48

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

27 Oct 202028 Feb 2035

First posted22 Nov 2019
Study start27 Oct 2020
Primary completion28 Feb 2035 (estimated)
Study completion28 Feb 2035 (estimated)

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Other trials for Pompe Disease (Late-onset)Studies of the same condition, open and under way.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase 1/2
Primary purpose: Treatment
Allocation: Non-randomised
Intervention model: Sequential
Model description: Up to 3 nominal dose levels of AT845 are planned to be evaluated in this study. A single AT845 administration via IV infusion is planned for each subject. The initial dosing cohort received a single dose of 3×10\^13 vg/kg. The second dose cohort will receive a single dose of 6×10\^13 vg/kg. The third dose cohort will receive a single dose of 1×10\^14 vg/kg. Dose escalation between cohorts will be based on evaluations of safety and in consultation with the independent DMC.
Masking: None (open label)
Enrolment: 11 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT04174105
Sponsor's protocol ID: AT845-01
Other IDs: 2019-003595-38, 2019
Acronym: FORTIS
Status last verified: Aug 2026
First submitted: 13 Nov 2019
Last updated: 2 Sep 2026
Results posted: No
Data monitoring committee: Yes
FDA-regulated drug: Yes
FDA-regulated device: No
Individual data sharing: No: Access to anonymized individual participant level data will not be provided for this trial. Further details on Astellas' data sharing policy can be found at https://www.clinicaltrials.astellas.com/transparency/.

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See locations

Active, not recruiting
Effects of Whole-body Electrical Muscle Stimulation Exercise on Adults With Neuromuscular Disease
Neuromuscular Diseases (NMD), Amyotrophic Lateral Sclerosis
RecruitingObservational study
Pompe Disease Registry Protocol
Glycogen Storage Disease Type II, Pompe Disease
Not yet recruitingPhase 2
An Extension Study of S-606001 in Participants With Late-onset Pompe Disease (LOPD)
Pompe Disease
RecruitingPhase 1/2
A Study to Evaluate Safety, Tolerability, and Efficacy of AB-1009 Gene Therapy (GAA Gene) in Adult Participants With Late-Onset Pompe Disease (PROGRESS-GT LOPD)
Pompe Disease (Late-onset), Pompe Disease Late-Onset
Active, not recruiting
A Study About Antibody Levels and Biomarkers in the Blood in People With Late-onset Pompe Disease
Pompe Disease (Late-onset)

All Pompe Disease (Late-onset) trials

Study at a glance

From the registry record, last updated by the sponsor on 2 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: A Phase 1/2, Open-Label, Ascending-Dose Clinical Study to Evaluate the Safety and Preliminary Efficacy of AT845, an AAV8-Delivered Gene Transfer Therapy in Patients With Late Onset Pompe Disease
ClinicalTrials.gov ID: NCT04174105
Acronym / sponsor ID: FORTIS / AT845-01
Conditions: Pompe Disease (Late-onset)
Keywords: LOPD
Phase: Phase 1/2
Study type: Interventional
Recruitment status: Active, not recruiting
Enrolment: 11 participants (actual)
Lead sponsor: Astellas Gene TherapiesIndustry (pharma, biotech, devices)
Study start: 27 Oct 2020 (actual)
Primary completion: 28 Feb 2035 (estimated)
Study completion: 28 Feb 2035 (estimated)
First posted: 22 Nov 2019 (actual)
Results: Not posted in the source record

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Detailed description

Study design

Primary purpose: Treatment
Allocation: Non-randomised
Intervention model: Sequential
Masking: None (open label)
Number of arms: 3
Model description: Up to 3 nominal dose levels of AT845 are planned to be evaluated in this study. A single AT845 administration via IV infusion is planned for each subject. The initial dosing cohort received a single dose of 3×10^13 vg/kg. The second dose cohort will receive a single dose of 6×10^13 vg/kg. The third dose cohort will receive a single dose of 1×10^14 vg/kg. Dose escalation between cohorts will be based on evaluations of safety and in consultation with the independent DMC.

Arm	Type	Receives
Initial Dose Cohort	Experimental	Genetic: zocaglusagene nuzaparvovec3x10^13 vg/kg of AT845 administered via intravenous infusion
Second Dose Cohort	Experimental	Genetic: zocaglusagene nuzaparvovec6x10^13 vg/kg of AT845 administered via intravenous infusion
Third Dose Cohort	Experimental	Genetic: zocaglusagene nuzaparvovec1x10^14 vg/kg of AT845 administered via intravenous infusion

Who may qualify

Ages: 18 to 80 years
Sex: All
Healthy volunteers: Not accepted
Age groups: Adult, Older adult

Key inclusion criteria (9 listed)

Participant is aged ≥ 18 years.
Participant has a documented clinical diagnosis of Pompe disease by genetic testing.
Participant has received enzyme replacement therapy (ERT) with rhGAA for the previous ≥ 2 years.
Participant has been on a stable standard dose (at least 20 mg/kg every 2 weeks) of ERT with rhGAA for at least the previous 6 months.
Participant or legally authorized representative(s) (LAR) (if applicable) provides written informed consent.

Key exclusion criteria (29 listed)

Participant is currently participating in an interventional study or has received gene or cell therapy.
Participant tests positive for AAV8 antibodies with titers >1:20 neutralizing.
Participant has received immune-modulating agents within 90 days before dosing (use of inhaled corticosteroids is allowed); use of other concomitant medications to manage chronic conditions must have been stable for at least 30 days before dosing. Concomitant medications that may predispose the participant to peripheral neuropathy will be evaluated.
Participant has any clinically significant laboratory values (other than those directly associated with LOPD [e.g., GAA, serum creatine kinase (CK)]) that would preclude participation in the study.
Participant has serological or viral load evidence of HIV-1 or HIV-2.

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
zocaglusagene nuzaparvovecAlso: AT845AT845 is an AAV8 vector delivering a functional copy of the human GAA gene, under the control of a muscle-specific promoter	Genetic	Initial Dose Cohort, Second Dose Cohort, Third Dose Cohort

Primary outcome

Safety and Tolerability over time
Time frame: Up to month 120
Frequency of adverse events (AEs), serious adverse events (SAEs), and changes from baseline in relevant clinical laboratory tests
GAA enzymatic activity
Time frame: Baseline and Week 12
Change from baseline in GAA enzymatic activity in muscle biopsies at week 12
GAA protein expression
Time frame: Baseline and Week 12
Change from baseline in GAA protein expression in muscle biopsies at week 12.

11 secondary outcomes

Vector Copy Number
Time frame: Baseline and Week 12
Thigh Fat Fraction
Time frame: Baseline and Month 18
6-Minute Walk Test (for ambulatory patients)
Time frame: Baseline, Week 24 and Week 48
Percentage Predicted for 6-Minute Walk Test (for ambulatory patients)
Time frame: Baseline, Week 24 and Week 48
Forced Vital Capacity (FVC)
Time frame: Baseline, Week 24 and Week 48
Maximum Inspiratory Pressure (MIP)
Time frame: Baseline, Week 24 and Week 48
Maximum Expiratory Pressure (MEP)
Time frame: Baseline, Week 24 and Week 48
The Gait, Stairs, Gower Maneuver, Chair (GSGC)
Time frame: Baseline, Week 24 and Week 48
Rasch-built Pompe-specific Activity (R-PAct) scale
Time frame: Baseline and Week 48
EuroQol 5 Dimensions 5 Levels (EQ-5D-5L) Questionnaire
Time frame: Baseline and Week 48
Patient-Reported Outcomes Measurement Information System (PROMIS)
Time frame: Baseline and Week 48

Results and safety

This study is still under way. Results are not available in the source record yet.

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 2 Sep 2026.
Individual participant dataSharing planned: No. Access to anonymized individual participant level data will not be provided for this trial. Further details on Astellas' data sharing policy can be found at https://www.clinicaltrials.astellas.com/transparency/.

Related trials for Pompe Disease (Late-onset)

Active, not recruiting
Effects of Whole-body Electrical Muscle Stimulation Exercise on Adults With Neuromuscular Disease
Neuromuscular Diseases (NMD), Amyotrophic Lateral Sclerosis
RecruitingObservational study
Pompe Disease Registry Protocol
Glycogen Storage Disease Type II, Pompe Disease
Not yet recruitingPhase 2
An Extension Study of S-606001 in Participants With Late-onset Pompe Disease (LOPD)
Pompe Disease
RecruitingPhase 1/2
A Study to Evaluate Safety, Tolerability, and Efficacy of AB-1009 Gene Therapy (GAA Gene) in Adult Participants With Late-Onset Pompe Disease (PROGRESS-GT LOPD)
Pompe Disease (Late-onset), Pompe Disease Late-Onset
Active, not recruiting
A Study About Antibody Levels and Biomarkers in the Blood in People With Late-onset Pompe Disease
Pompe Disease (Late-onset)

Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

Medical Director study director

Astellas Pharma Global Development, Inc.

4 sites in 2 countries: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A Phase 1/2 study testing zocaglusagene nuzaparvovec in people with Pompe Disease (Late-onset), run by Astellas Gene Therapies at 4 sites in 2 countries.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 9 inclusion and 29 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: under way, not looking for participants, as of the sponsor's last update on 2 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 4 sites in United States, United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this combined phase mean?

Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.

Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Safety and Tolerability over time (time frame: Up to month 120). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT04174105.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 2 Sep 2026.