Home-based ERT for Pompe can be safely implemented, study suggests
Surveys were conducted in the Netherlands, where it's been available for 15 years
“Insights from this study can be used as a base for implementing home-based ERT in other countries and to further optimize patient care,” researchers wrote.
The study, “Home-based enzyme replacement therapy in children and adults with Pompe disease; a prospective study,” was published in the Orphanet Journal of Rare Diseases.
More than 80% of Pompe patients in the Netherlands receive ERT at home
Pompe disease is caused by mutations in the GAA gene, which provides instructions to produce the enzyme acid alpha-glucosidase that’s required to break down a complex sugar molecule called glycogen.
Enzyme deficiency leads to the toxic accumulation of glycogen inside cells, particularly muscle cells, leading to symptoms such as progressive muscle weakness and breathing problems.
ERT involves the administration of a functional enzyme that replaces the dysfunctional or missing enzyme in Pompe patients. In the U.S., Lumizyme (sold outside the U.S. as Myozyme) and Nexviazyme are approved ERTs for Pompe disease.
Home-based ERT has been available in the Netherlands since 2008, where it has been shown to be safe and to reduce treatment burden. It also increases patients’ autonomy and flexibility in access to treatment. More than 80% of those with Pompe disease in the Netherlands receive their ERT infusions at home. However, in most countries, the treatment is administered in the hospital due to the risk of severe reactions associated with the infusion.
In this study, researchers surveyed 116 Pompe disease patients receiving home-based ERT: 17 patients had the classic infantile-onset disease, while two had atypical infantile-onset, 15 had childhood-onset, and 82 had adult-onset disease.
Insights from this study can be used as a base for implementing home-based ERT in other countries and to further optimize patient care.
Patients were eligible for home-based ERT infusions after one year of receiving the treatment at the hospital, if ERT was found to be safe and without recent infusion-associated reactions (IARs).
The participants had a median age of 51.8 years, and were undergoing ERT for a median of 11.3 years. They filled out a total of 423 questionnaires in one year, corresponding to an overall response rate of 88.1%. The questionnaire evaluated the previous treatment infusion, and the IARs in the three months before filling out the questionnaire.
Most patients (85.3%) did not report ERT-associated health complaints to the treating hospital, Erasmus MC University Medical Center. However, 17 patients reported health complaints 27 times during or within two days after the infusion. Fatigue was the most common complaint (in 11 patients, 9.5%), followed by headaches in nine patients (7.8%), and seven patients reported feeling unwell (6%).
Gastrointestinal complaints such as abdominal pain, diarrhea, heartburn, and vomiting were only reported after the infusion. The only complaint reported during infusion was nausea.
Those who were sick or ill before the infusion were more likely to experience health complaints. This is “possibly due to activation of the immune system,” according to the researchers.
Specifically, there were five complaints in 13 questionnaires of patients reported to be sick before the infusion (38.5%), versus 22 complaints on 410 questionnaires of those who were not sick before the infusion (5.4%).
In four instances, reported by two patients with classic infantile-onset disease (14.8%), the health complaints were reported to the hospital as IARs, including skin rash, chills, headache, fever, skin redness, and itching.
‘This study demonstrates that home-based ERT in Pompe disease is safe’
For the three months before the questionnaire, most patients (96.2%) reported no IARs. However, three classic infantile-onset disease patients indicated experiencing IARs in one or several questionnaires, some of which were reported to the hospital.
In these patients, 25 interventions resolved all IARs, including pausing the infusion, contacting the hospital, giving medications, and adapting the infusion speed. One patient was admitted to hospital due to fluid retention and defecation problems. None of the IARs required emergency care.
Among adult-onset disease patients, three indicated experiencing IARs. In total, five interventions, such as giving medication or contacting the hospital, resolved nearly all cases.
Steps to prevent IARs at subsequent infusions included premedication and adapting the infusion schedule.
No IARs were reported during the one-year follow-up among atypical infantile-onset and childhood-onset patients.
“This study demonstrates that home-based ERT in Pompe disease is safe across [disease types]. We did not encounter any new ERT-related health problems,” the researchers wrote.
They noted that it is essential to “inquire whether the patient experiences minor health complaints around infusions during outpatient clinic visits. If any complaints are reported, then the burden of these complaints should be explored, and medical action should be taken if necessary.”