NEW YORK (Reuters Health) - Long-term, continuous enzyme replacement therapy (ERT) with alglucerase or imiglucerase in children with Gaucher disease type 1 normalizes linear growth, enhances bone mineralization, and reduces liver and spleen volume, according to data from a large registry study.
Many cases of Gaucher disease type 1 begin in childhood, and disease manifestations -- organomegaly, hematologic disorders, and bone disease -- tend to be worse in pediatric cases than in adults, Dr. Hans C. Andersson and colleagues note in the December issue of Pediatrics. Until now, there have been no reports on the specific effects of ERT in a large cohort of children.
Dr. Andersson, at Tulane University Medical School in New Orleans, and his associates analyzed data from the International Collaborative Gaucher Group Registry for 884 subjects up to 18 years of age treated with alglucerase or imiglucerase (Ceredase or Cerezyme, both from Genzyme) for 8-12 years. Mean ERT dose was 78.6 U/kg per 4 weeks.
Median height z score for the study population improved from -1.4 to -0.3. "After 8 years of enzyme replacement therapy, the patients' median height was not substantially different from the median for the normal population," the authors report. Similar results were observed for median bone mineral density z score after 12 years' treatment (-0.35 at baseline; 0.29 at final follow-up).
Patients also demonstrated significant reductions in liver and spleen volume size, as well as significant improvement in hemoglobin levels and platelet counts.
Most disease manifestations resolved substantially during the first year, with continued improvement for the duration of treatment.
The authors note that prior to enzyme treatment, 90 patients had reported bone crises -- that is, acute bone pain that required immobilization of the affected area and narcotic treatment lasting longer than 3 days. "After 2 years of ERT, there were no new bone crises among patients who reported an event before initiation of ERT," they report.
"The study shows the ongoing benefit of ERT… for pediatric patients over many years, justifying the need for continuous long-term treatment," Dr. Andersson's group concludes.
They advise that patients who do not maintain a response to ERT should be reevaluated for complicating factors, such as comorbid illness or neutralizing antibodies.
