Glycogen Storage Disease Type II Late OnsetPhase 4AVANCT07652814

Safety and Efficacy of Avalglucosidase Alfa in Patients With Non-classic Pompe Disease Aged ≥ 5 Years

A Phase 4 study testing Avalglucosidase Alfa in people with Glycogen Storage Disease Type II Late Onset and Pompe Disease (Late-onset), run by Iris Plug at 1 site in Netherlands.

Active, not recruiting

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

Official record

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Trial summary

The goal of this clinical trial is to study the efficacy and safety of treatment with avalglucosidase alfa in patients with late onset Pompe disease that previously deteriorated on alglucosidase alfa. Read more about this study

Who is it for?: Ages 5 to 55 years
Conditions the study is for: Glycogen Storage Disease Type II Late Onset, Pompe Disease (Late-onset), Pompe Disease Late-Onset
What is being tested?: Avalglucosidase Alfa
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 6 participants
Where: 1 siteNetherlands
Study dates: 13 Oct 2022to 9 Mar 2028
Phase: Phase 4
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 5 to 55 years
All sexes
No healthy volunteers
Child, Adult

Who may be able to join

Age> 5 years and < 55 years
Childhood or juvenile/adult onset
Residing in the Netherlands
Current ERT with alglucosidase alfa> 2 years (dose regimen 20 or 40 mg/kg bi-weekly).
Confirmed diagnosis: enzyme deficiency in any tissue source and/or 2 confirmed disease-causing variants in the GAA gene.
Willing and able to adhere to study procedures
Deterioration in pulmonary function and/or 6MWT and/or muscle strength despite current treatment regimen with alglucosidase alfa.
Disease status: measurable pulmonary (dys)function: (F)VC ≤ 80% predicted (mechanic ventilation during the day or night allowed); Measurable muscle weakness in proximal and/or distal muscle groups (non- ambulant/wheelchair bound patients allowed); measurable functional ability

Who cannot join

Age>55 years
Invasive mechanical ventilation
No remaining useful functional ability, as decided by the treating physician
Unmanageable, sever IAR's on alglucosidase alfa
Deterioration due to high levels of anti-alglucosidase alfa antibodies interfering with treatment efficacy
Female patient of childbearing potential not protected by highly effective contraceptive method of birth control and/or who is unwilling or unable to be tested for pregnancy

Trial locations and contacts

1 site in 1 country.

Netherlands1 site

Erasmus MC
Rotterdam, 3015 GD

Other trials in Netherlands

About this study

Official title: An Open Label, Single Center, Exploratory Study of the Safety and Efficacy of Avalglucosidase Alfa Patients With Non-classic Pompe Disease Aged ≥ 5 Years

The main question it aims to answer is:

Is switching to avalglucosidase alfa in late-onset Pompe patients deteriorating on alglucosidase alfa safe?
Is switching to avalglucosidase alfa in late-onset Pompe patients deteriorating on alglucosidase alfa potentially more effective?

Participants will switch to biweekly avalglucosidase alfa infusions (instead of alglucosidase alfa infusions) and perform assessment for:

Efficacy: muscle strength and function, pulmonary function, patient-reported outcomes.
Safety: Adverse events assessment, physical examination, clinical laboratory evaluations, vital signs, ECGs and immunogenicity assessments.
Pharmacokinetic assessments during 2 avalglucosidase alfa infusions.

Read the detailed description

Rationale: Not all patients with non-classic Pompe disease have a good response to current treatment with alglucosidase alfa. Therefore innovative enzyme replacement therapies are developed. The study drug avalglucosidase alfa has been tested in multiple clinical studies and will now be studied in a small population of patients that are unresponsive to alglucosidase alfa.

Objective: To explore safety, tolerability and efficacy of avalglucosidase alfa in patients with non-classic Pompe disease aged ≥ 5 years of whom clinical condition deteriorates while on standard treatment with alglucosidase alfa.

Study design: Single-center, open-label, repeated bi-weekly intravenous infusion study of avalglucosidase alfa in patients with non-classic Pompe disease patients aged ≥ 5 years, previously treated with alglucosidase alfa.

Study population: Non-classic Pompe disease patients aged ≥ 5 years and ≤ 55 years previously treated ≥ 2 years with alglucosidase alfa, who deteriorate despite treatment with alglucosidase alfa at a dose of 20 or 40 mg/kg bi-weekly.

Total number of patients = 6.

Intervention: Avalglucosidase alfa. Sterile lyophilized powder administered by intravenous infusion following reconstitution and dilution. 20 mg/kg bi-weekly

Main study parameters:

Safety
Assessment of adverse events / treatment-emergent adverse events, including infusion associated reactions (IARs)
Clinical laboratory evaluations including hematology, biochemistry, urinalysis
Immunogenicity assessments
Pharmacokinetics
Single and multiple dose estimates for Cmax, AUC, CL,.
Efficacy
Muscle strength: manual muscle testing (MMT), hand- held dynamometry (HHD).
Muscle function: Quick Motor Function test (QMFT), six Minute Walk Test (6MWT), timed tests.
Pulmonary function: (forced) vital capacity ((F)VC) in sitting and supine positions, Maximum Inspiratory Pressure (MIP), Maximum Expiratory Pressure (MEP).
'PRO-measures': Rasch-build Pompe Activity scale (R- Pact), Quality of Life (QoL), modified Borg scale,

Nature and extent of burden and risks associated with participation, benefit and group relatedness: Blood samples will be collected at 14 time points, the amount of blood will not exceed the maximum amount of 5 ML/kg over a period of 8 weeks. Patients will visit the hospital every other week to receive treatment. This treatment will last 4-6 hours. During every visit the vital signs of the patients will be checked and a physical examination is performed.

Conditions: Glycogen Storage Disease Type II Late Onset, Pompe Disease (Late-onset), Pompe Disease Late-Onset, Pompe's Disease Juvenile Onset, Pompe Disease
Being tested: Avalglucosidase Alfa
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.

Avalglucosidase AlfaDrug
Enzyme replacement therapy

Study groups in NCT07652814
Study group	Role	What they receive
avalglucosidase alfa treatment	Other	Treatment with avalglucosidase alfa, 20 mg/kg/every other week for a period of 5 years. Receives: Drug: Avalglucosidase Alfa

What is being measured

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

Incidence/occurrence of adverse events
Assessment of the occurrence/number of adverse events / treatment-emergent adverse events, including infusion associated reactions (IARs). Adverse events are scored using the Common Terminology Criteria for Adverse Events (CTCAE), version 5.0.
Measured: From enrollment to the end of study duration at 5 years
The occurence of antibodies against avalglucosidase alfa
The titer of antibodies against avalglucosidase alfa, scored as either no to low antibodies (< 1:1,250), intermediate (1:1,250 to < 1:31,250), or high (≥ 1:31,250).
Measured: From enrollment to the end of study duration at 5 years
Clinical laboratory evaluations aimed at liver and muscle function.
Values of ASAT, ALAT and CK (measured in U/L) as markers for muscle and liver function.
Measured: From enrollment to the end of study duration at 5 years
Changes in muscle strength using manual muscle testing (MMT)
Manual muscle testing (MMT) is performed using the Medical Research Council (MRC) grading scale. Muscle strength is graded from 0-5 by physical examination, in which grade 5 represents normal muscle strength and grade 0 means paralysis of the muscle group tested.
Measured: From enrollment to the end of study duration at 5 years
Changes in muscle strength using hand-held dynamometry (HHD)
Muscle strength will also be measured with the Cytec handheld dynamometer (HHD). A mean value in Newton is calculated from three consecutive measurements per muscle group.
Measured: From enrollment to the end of study duration at 5 years
Changes in muscle function using Quick Motor Function Test (QMFT)
For the quick motor function test, the patient is asked to perform several activities in supine, sitting and standing position, the performance of the patient is scored on a 5-point ordinal scale (range 0-4). A sumscore is calculated based on the maximum total score.
Measured: From enrollment to the end of study duration at 5 years
Changes in muscle function using the 6-Minute Walk Test (6-MWT)
The 6MWT is a timed test that measures functional endurance. The primary measurement is the distance walked in 6 minutes, measured in meters. The percent of predicted distance and the amount of time walked (to quantify endurance, as not all patients may complete the full 6-minute walk) will also be recorded.
Eventual score is reported as a distance in meters (m) and a percent of the predicted score using the 1000 norms reference values.
Measured: From enrollment to the end of study duration at 5 years
Changes in muscle function using timed tests
Four timed tests will be performed to evaluate the impact of muscle weakness on the ability to perform functional activities of daily living. These timed tests include walking 10 meters, climbing four stairs, getting up from a supine position on the floor, and standing up from a chair. The number of seconds required to perform each activity will be noted.
Measured: From enrollment to the end of study duration at 5 years
Changes in pulmonary function using forced vital capacity (FVC)
Forced vital capacity in sitting and supine position will be measured and reported as percentage of predicted values, using the GLI 2012 reference values.
Measured: From enrollment to the end of study duration at 5 years
Changes in pulmonary function using Maximum Inspiratory Pressure (MIP) and Maximum Expiratory Pressure (MEP)
Both MIP and MEP are measured in kPa and then converted to a percentage of predicted values based on reference values.
Measured: From enrollment to the end of study duration at 5 years
Changes in patient reported outcome (PRO) measures using the Rasch-built Pompe-specific Activity scale (R-PAct)
The Rasch-Built Pompe-specific activity scale (R-PAct) will be performed in all patients who are ≥16 years at baseline. The R-PAct scale is a self-reported, 18-items questionnaire designed specifically for use in patients with Pompe disease, based upon experiences from patients about their most important and limiting aspects in daily life. All items have three response options: [0] unable to perform; [1] able to perform, but with difficulty or [2] able to perform without difficulty. If all items are answered, an appropriate centile metric score (range 0-100) will be calculated.
Measured: From enrollment to the end of study duration at 5 years
Changes in patient reported outcome (PRO) measures using the 36-Item Short Form Health Survey (SF-36)
The SF-36 is a health-related quality of life questionnaire, consisting of 36 items. The items are assigned to the domains of physical functioning, role functioning-physical, role functioning- emotional, social functioning, body pain, mental health, vitality, general health perception and change in health. The questionnaire will be used only for patients aged 16 years and older.
A sumscore will be calculated based on the score on each item, and converted to a percentage of predicted score based on Dutch norm-based values.
Measured: From enrollment to the end of study duration at 5 years
Changes in patient reported outcome (PRO) measures using the TNO-AZL Child Quality of Life Questionnaire)
The TACQOL (TNO-AZL Child Quality of Life Questionnaire) is a generic instrument that measures quality of life in children aged 6-15 years. The questionnaire includes items representing the following concepts: physical complaints, motor functioning, autonomous functioning, social functioning, cognitive functioning, positive moods, and negative moods. For each of these scales, a scale score is calculated, where a higher score corresponds with a better quality of life.
Measured: From enrollment to the end of study duration at 5 years
Changes in patient reported outcome (PRO) measures using the modified Borg scale
The modified Borg scale is a patient-reported scale, derived from the original Borg scale, which is used to assess the subjective sensation of dyspnea of a patient. It is quantified from 0 to 10, in which 0 represents no symptoms (i.e. no dyspnea/shortness of breath) and 10 represents maximum symptoms.
Measured: From enrollment to the end of study duration at 5 years
Pharmacokinetics of avalglucocidase alfa
Single and multiple dose estimates for Cmax (in µg/mL), AUC (in μg∙hr/ml) and CL (in L/h), measured at two separate avalglucosidase alfa infusions (at baseline and 52 weeks).
Measured: From enrollment up to 1 year of study duration.

Secondary outcomes (5)

Changes in vital signs using heart rate
Heart rate in beats per minute (bpm), scored prior to infusion, with each change in infusion rate and at the end of infusion.
Measured: From enrollment to the end of study duration at 5 years
Changes in vital signs using blood pressure
Systolic and diastolic blood pressure in mmHg, scored prior to infusion, with each change in infusion rate and at the end of infusion.
Measured: From enrollment to the end of study duration at 5 years
Changes in vital signs using respiratory rate
Respiratory rate measured in number of breaths per minute, scored prior to infusion, with each change in infusion rate and at the end of infusion
Measured: From enrollment to the end of study duration at 5 years
Changes or abnormalities of cardiac function measured by electrocardiogram (ECG)
A standard 12-lead electrocardiogram (ECG) will be performed using an electrocardiographic device.
The following variables will be assessed: heart rate (beats per minute), rhythm (type), interval from start of the Q wave to the end of the S wave (QRS) in milliseconds (ms), interval between the peaks of successive QRS complexes (RR) in ms, interval from the beginning of the P wave until the beginning of the QRS complex (PR) in ms, interval between the start of the Q wave and the end of the T wave (QT) in ms, QT interval corrected for heart rate (QTc) automatic correction evaluation (by the ECG device) in ms, QRS axis (direction), presence of left ventricular hypertrophy criteria, presence right ventricular hypertrophy criteria, and presence of repolarization charges (yes/no).
These measurements will be aggregated to arrive at one reported outcome measure: abnormal ECG (Yes/No). Abnormal ECG is defined as an abnormality in any of the measurements mentioned above.
Measured: From enrollment to the end of study duration at 5 years
Assessment of use of ventilator
At each visit use of mechanical ventilation will be assessed, including the hours of ventilation per day - if applicable.
Measured: From enrollment to the end of study duration at 5 years

Timeline

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

13 Oct 20229 Mar 2028

First posted17 Jun 2026
Study start13 Oct 2022
Primary completion9 Mar 2028 (estimated)
Study completion9 Mar 2028 (estimated)

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Other trials for Glycogen Storage Disease Type II Late OnsetStudies 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 4
Primary purpose: Treatment
Allocation: Not applicable
Intervention model: Single group
Model description: 6 patients with late onset Pompe disease will be treated
Masking: None (open label)
Enrolment: 6 participants (estimated)

IDs, dates and publications

ClinicalTrials.gov ID: NCT07652814
Sponsor's protocol ID: NL70885.078.21
Other IDs: 2024-518215-18-00, 2019-002251-42, 2019
Acronym: AVA
Status last verified: Jun 2026
First submitted: 1 Nov 2022
Last updated: 17 Jun 2026
Results posted: No
Data monitoring committee: No
FDA-regulated drug: No
FDA-regulated device: No
Individual data sharing: No

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

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All Glycogen Storage Disease Type II Late Onset trials

Study at a glance

From the registry record, last updated by the sponsor on 17 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: An Open Label, Single Center, Exploratory Study of the Safety and Efficacy of Avalglucosidase Alfa Patients With Non-classic Pompe Disease Aged ≥ 5 Years
ClinicalTrials.gov ID: NCT07652814
Acronym / sponsor ID: AVA / NL70885.078.21
Conditions: Glycogen Storage Disease Type II Late Onset, Pompe Disease (Late-onset), Pompe Disease Late-Onset, Pompe's Disease Juvenile Onset, Pompe Disease
Phase: Phase 4
Study type: Interventional
Recruitment status: Active, not recruiting
Enrolment: 6 participants (estimated)
Lead sponsor: Iris PlugUniversity, hospital or other
Collaborators: Sanofi
Study start: 13 Oct 2022 (actual)
Primary completion: 9 Mar 2028 (estimated)
Study completion: 9 Mar 2028 (estimated)
First posted: 17 Jun 2026 (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.

The main question it aims to answer is:

Is switching to avalglucosidase alfa in late-onset Pompe patients deteriorating on alglucosidase alfa safe?
Is switching to avalglucosidase alfa in late-onset Pompe patients deteriorating on alglucosidase alfa potentially more effective?

Participants will switch to biweekly avalglucosidase alfa infusions (instead of alglucosidase alfa infusions) and perform assessment for:

Efficacy: muscle strength and function, pulmonary function, patient-reported outcomes.
Safety: Adverse events assessment, physical examination, clinical laboratory evaluations, vital signs, ECGs and immunogenicity assessments.
Pharmacokinetic assessments during 2 avalglucosidase alfa infusions.

Detailed description

Total number of patients = 6.

Intervention: Avalglucosidase alfa. Sterile lyophilized powder administered by intravenous infusion following reconstitution and dilution. 20 mg/kg bi-weekly

Main study parameters:

Safety
Assessment of adverse events / treatment-emergent adverse events, including infusion associated reactions (IARs)
Clinical laboratory evaluations including hematology, biochemistry, urinalysis
Immunogenicity assessments
Pharmacokinetics
Single and multiple dose estimates for Cmax, AUC, CL,.
Efficacy
Muscle strength: manual muscle testing (MMT), hand- held dynamometry (HHD).
Muscle function: Quick Motor Function test (QMFT), six Minute Walk Test (6MWT), timed tests.
Pulmonary function: (forced) vital capacity ((F)VC) in sitting and supine positions, Maximum Inspiratory Pressure (MIP), Maximum Expiratory Pressure (MEP).
'PRO-measures': Rasch-build Pompe Activity scale (R- Pact), Quality of Life (QoL), modified Borg scale,

Study design

Primary purpose: Treatment
Allocation: Not applicable
Intervention model: Single group
Masking: None (open label)
Number of arms: 1
Model description: 6 patients with late onset Pompe disease will be treated

Arm	Type	Receives
avalglucosidase alfa treatment	Other	Drug: Avalglucosidase AlfaTreatment with avalglucosidase alfa, 20 mg/kg/every other week for a period of 5 years.

Who may qualify

Ages: 5 to 55 years
Sex: All
Healthy volunteers: Not accepted
Age groups: Child, Adult

Key inclusion criteria (8 listed)

Age> 5 years and < 55 years
Childhood or juvenile/adult onset
Residing in the Netherlands
Current ERT with alglucosidase alfa> 2 years (dose regimen 20 or 40 mg/kg bi-weekly).
Confirmed diagnosis: enzyme deficiency in any tissue source and/or 2 confirmed disease-causing variants in the GAA gene.

Key exclusion criteria (6 listed)

Age>55 years
Invasive mechanical ventilation
No remaining useful functional ability, as decided by the treating physician
Unmanageable, sever IAR's on alglucosidase alfa
Deterioration due to high levels of anti-alglucosidase alfa antibodies interfering with treatment efficacy

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
Avalglucosidase AlfaEnzyme replacement therapy	Drug	avalglucosidase alfa treatment

Primary outcome

Incidence/occurrence of adverse events
Time frame: From enrollment to the end of study duration at 5 years
Assessment of the occurrence/number of adverse events / treatment-emergent adverse events, including infusion associated reactions (IARs). Adverse events are scored using the Common Terminology Criteria for Adverse Events (CTCAE), version 5.0.
The occurence of antibodies against avalglucosidase alfa
Time frame: From enrollment to the end of study duration at 5 years
The titer of antibodies against avalglucosidase alfa, scored as either no to low antibodies (< 1:1,250), intermediate (1:1,250 to < 1:31,250), or high (≥ 1:31,250).
Clinical laboratory evaluations aimed at liver and muscle function.
Time frame: From enrollment to the end of study duration at 5 years
Values of ASAT, ALAT and CK (measured in U/L) as markers for muscle and liver function.
Changes in muscle strength using manual muscle testing (MMT)
Time frame: From enrollment to the end of study duration at 5 years
Manual muscle testing (MMT) is performed using the Medical Research Council (MRC) grading scale. Muscle strength is graded from 0-5 by physical examination, in which grade 5 represents normal muscle strength and grade 0 means paralysis of the muscle group tested.
Changes in muscle strength using hand-held dynamometry (HHD)
Time frame: From enrollment to the end of study duration at 5 years
Muscle strength will also be measured with the Cytec handheld dynamometer (HHD). A mean value in Newton is calculated from three consecutive measurements per muscle group.
Changes in muscle function using Quick Motor Function Test (QMFT)
Time frame: From enrollment to the end of study duration at 5 years
For the quick motor function test, the patient is asked to perform several activities in supine, sitting and standing position, the performance of the patient is scored on a 5-point ordinal scale (range 0-4). A sumscore is calculated based on the maximum total score.
Changes in muscle function using the 6-Minute Walk Test (6-MWT)
Time frame: From enrollment to the end of study duration at 5 years
The 6MWT is a timed test that measures functional endurance. The primary measurement is the distance walked in 6 minutes, measured in meters. The percent of predicted distance and the amount of time walked (to quantify endurance, as not all patients may complete the full 6-minute walk) will also be recorded. Eventual score is reported as a distance in meters (m) and a percent of the predicted score using the 1000 norms reference values.
Changes in muscle function using timed tests
Time frame: From enrollment to the end of study duration at 5 years
Four timed tests will be performed to evaluate the impact of muscle weakness on the ability to perform functional activities of daily living. These timed tests include walking 10 meters, climbing four stairs, getting up from a supine position on the floor, and standing up from a chair. The number of seconds required to perform each activity will be noted.
Changes in pulmonary function using forced vital capacity (FVC)
Time frame: From enrollment to the end of study duration at 5 years
Forced vital capacity in sitting and supine position will be measured and reported as percentage of predicted values, using the GLI 2012 reference values.
Changes in pulmonary function using Maximum Inspiratory Pressure (MIP) and Maximum Expiratory Pressure (MEP)
Time frame: From enrollment to the end of study duration at 5 years
Both MIP and MEP are measured in kPa and then converted to a percentage of predicted values based on reference values.
Changes in patient reported outcome (PRO) measures using the Rasch-built Pompe-specific Activity scale (R-PAct)
Time frame: From enrollment to the end of study duration at 5 years
The Rasch-Built Pompe-specific activity scale (R-PAct) will be performed in all patients who are ≥16 years at baseline. The R-PAct scale is a self-reported, 18-items questionnaire designed specifically for use in patients with Pompe disease, based upon experiences from patients about their most important and limiting aspects in daily life. All items have three response options: [0] unable to perform; [1] able to perform, but with difficulty or [2] able to perform without difficulty. If all items are answered, an appropriate centile metric score (range 0-100) will be calculated.
Changes in patient reported outcome (PRO) measures using the 36-Item Short Form Health Survey (SF-36)
Time frame: From enrollment to the end of study duration at 5 years
The SF-36 is a health-related quality of life questionnaire, consisting of 36 items. The items are assigned to the domains of physical functioning, role functioning-physical, role functioning- emotional, social functioning, body pain, mental health, vitality, general health perception and change in health. The questionnaire will be used only for patients aged 16 years and older. A sumscore will be calculated based on the score on each item, and converted to a percentage of predicted score based on Dutch norm-based values.
Changes in patient reported outcome (PRO) measures using the TNO-AZL Child Quality of Life Questionnaire)
Time frame: From enrollment to the end of study duration at 5 years
The TACQOL (TNO-AZL Child Quality of Life Questionnaire) is a generic instrument that measures quality of life in children aged 6-15 years. The questionnaire includes items representing the following concepts: physical complaints, motor functioning, autonomous functioning, social functioning, cognitive functioning, positive moods, and negative moods. For each of these scales, a scale score is calculated, where a higher score corresponds with a better quality of life.
Changes in patient reported outcome (PRO) measures using the modified Borg scale
Time frame: From enrollment to the end of study duration at 5 years
The modified Borg scale is a patient-reported scale, derived from the original Borg scale, which is used to assess the subjective sensation of dyspnea of a patient. It is quantified from 0 to 10, in which 0 represents no symptoms (i.e. no dyspnea/shortness of breath) and 10 represents maximum symptoms.
Pharmacokinetics of avalglucocidase alfa
Time frame: From enrollment up to 1 year of study duration.
Single and multiple dose estimates for Cmax (in µg/mL), AUC (in μg∙hr/ml) and CL (in L/h), measured at two separate avalglucosidase alfa infusions (at baseline and 52 weeks).

5 secondary outcomes

Changes in vital signs using heart rate
Time frame: From enrollment to the end of study duration at 5 years
Changes in vital signs using blood pressure
Time frame: From enrollment to the end of study duration at 5 years
Changes in vital signs using respiratory rate
Time frame: From enrollment to the end of study duration at 5 years
Changes or abnormalities of cardiac function measured by electrocardiogram (ECG)
Time frame: From enrollment to the end of study duration at 5 years
Assessment of use of ventilator
Time frame: From enrollment to the end of study duration at 5 years

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 17 Jun 2026.
Individual participant dataSharing planned: No

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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.

Nadine van der Beek, MD PHD principal investigator

Erasmus Medical Center

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A Phase 4 study testing Avalglucosidase Alfa in people with Glycogen Storage Disease Type II Late Onset and Pompe Disease (Late-onset), run by Iris Plug at 1 site in Netherlands.

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 8 inclusion and 6 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 17 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Netherlands. 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 phase mean?

Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.

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?

Incidence/occurrence of adverse events (time frame: From enrollment to the end of study duration at 5 years). The study lists 15 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 NCT07652814.

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 17 Jun 2026.