Glycogen storage disease Type II
ICD-10 E74.0 · ICD-11 5C51.3.8

Glycogen Storage Disease Type II with Hypertrophic Cardiomyopathy: What to Do When Initial Enzyme Replacement Therapy Has Not Met Goals

Clinical Scenario

This protocol targets infantile-onset Pompe disease presenting at birth or within the first months of life, characterised by hypertrophic cardiomyopathy, in patients who are not CRIM (Cross Reactive Immune Material) negative. The disease may manifest with hypotonia, feeding difficulties, or respiratory problems from the earliest weeks of life.

Previous Treatment — Failure Condition

Prior line did not reach targets

The preceding regimen — enzyme replacement therapy (ERT) with Alglucosidase alfa — was directed at achieving improvement of hypertrophic cardiomyopathy, improved gross motor outcomes, and improved pulmonary function measures. This protocol applies when those goals have not been adequately met, or when a suboptimal response, clinical plateau, or clinical decline is observed on that regimen.

Next-Step Approach (Partial Overview)

Dose escalation strategy

The next step involves adjustment of Alglucosidase alfa dosing for patients who show inadequate response on the initial regimen. The specific thresholds for escalation, the complete dosing structure, and clinical decision criteria are defined in the full structured protocol.

Full regimen details — including dose levels, frequency, and decision algorithm — are available behind the link below.

Treatment Goals

Instant Access to Structured Evidence-Based Regimens

References

DOI: 10.1186/s13023-024-03373-w

The disease may be present at birth or within the first few months of life with hypotonia, feeding difficulties or respiratory problems.

A hypertrophic cardiomyopathy is characteristically present and may already develop in utero.

About one third of infantile Pompe disease patients, depending on their genotype, do not express any GAA protein and are defined CRIM negative.

Dose may be increased up to 40 mg/kg/eow or 40 mg/kg/w in patients with classic infantile and in late onset patients showing a suboptimal response, plateau, or clinical decline.

Further, a high-dose regimen of 40 mg/kg week showed a better effect on survival and also on walking ability than the recommend dose in classic infantile patients.

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