A long-term follow-up study analyzed the outcomes of 64 children with infantile-onset Pompe disease (PD) between 2004 and 2020, revealing high mortality and morbidity rates; the results were recently published in the European Journal of Neurology.
Enzyme replacement therapy for PD has been available in France since 2004, and this disease-modifying therapy has significantly improved survival among patients with infantile-onset PD. However, the production of anti-rhGAA antibodies could decrease the effectiveness of treatment in certain patients.
Studies focusing on long-term follow-up of large cohorts of patients with PD receiving enzyme replacement therapy are scarce. The authors aimed to retrospectively analyze the outcomes of 64 children with infantile-onset PD receiving enzyme replacement between 2004 and 2020.
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All of the included patients had cardiomyopathy at the time of diagnosis, and 92% had severe hypotonia. The median age at diagnosis was around 4 months.
Enzyme replacement therapy was initiated in 78% of patients, and an immunomodulation protocol was started in 27%. Enzyme replacement therapy was eventually stopped due to ineffectiveness in approximately 10% of patients receiving it; death occurred at a median of 11 months after treatment discontinuation.
Of the 64 included patients, 58% died at a median age of 13 years; this statistic included all patients with discontinued enzyme replacement therapy as well as 13 additional patients. Mortality reached its highest peaks before the age of 3 years and after the age of 12 years.
The authors noted that the rate of cardiomyopathy decreased as the population grew older. Conversely, the need for a wheelchair and ventilatory support increased with age. Only 2 patients survived to the age of 14 years, both requiring a wheelchair and ventilatory support.
“The main results of our study were the high mortality and morbidity rates at long term, with after an initial improvement with ERT, a secondary decline in muscular and respiratory functions,” the authors wrote. “This highlights the importance to develop new therapeutic approaches to target various aspects of pathogenesis and to improve long-term outcomes.”
Tardieu M, Cudejko C, Cano A, et al. Long‐term follow‐up of 64 children with classical infantile‐onset Pompe disease since 2004: a French real‐life observational study. Eur J Neurol. Published online May 26, 2023. doi:10.1111/ene.15894