Successful pregnancy and lactation outcome in a patient with Gaucher disease receiving enzyme replacement therapy, and the subsequent distribution and excretion of imiglucerase in human breast milk

Management and monitoring recommendations for the use of eliglustat in adults with type 1 Gaucher disease in Europe

PURPOSE

In Gaucher disease, diminished activity of the lysosomal enzyme, acid β-glucosidase, leads to accumulation of glucosylceramides and related substrates, primarily in the spleen, liver, and bone marrow. Eliglustat is an oral substrate reduction therapy approved in the European Union and the United States as a first-line treatment for adults with type 1 Gaucher disease who have compatible CYP2D6 metabolism phenotypes. A European Advisory Council of experts in Gaucher disease describes the characteristics of eliglustat that are distinct from enzyme augmentation therapy (the standard of care) and miglustat (the other approved substrate reduction therapy) and recommends investigations and monitoring for patients on eliglustat therapy within the context of current recommendations for Gaucher disease management.

RESULTS

Eliglustat is a selective, potent inhibitor of glucosylceramide synthase, the enzyme responsible for biosynthesis of glucosylceramides which accumulate in Gaucher disease. Extensive metabolism of eliglustat by CYP2D6, and, to a lesser extent, CYP3A of the cytochrome P450 pathway, necessitates careful consideration of the patient's CYP2D6 metaboliser status and use of concomitant medications which share metabolism by these pathways. Guidance on specific assessments and monitoring required for eliglustat therapy, including an algorithm to determine eligibility for eliglustat, are provided.

CONCLUSIONS

As a first-line therapy for type 1 Gaucher disease, eliglustat offers eligible patients a daily oral therapy alternative to biweekly infusions of enzyme therapy. Physicians will need to carefully assess individual Gaucher patients to determine their appropriateness for eliglustat therapy. The therapeutic response to eliglustat and use of concomitant medications will require long-term monitoring.

Imiglucerase in the management of Gaucher disease type 1: an evidence-based review of its place in therapy

Introduction

Gaucher disease is the first lysosomal disease to benefit from enzyme replacement therapy, thus serving as model for numerous other lysosomal diseases. Alglucerase was the first glucocerebrosidase purified from placental extracts, and this was then replaced by imiglucerase – a Chinese hamster ovary cell-derived glucocerebrosidase.

Aim

The aim was to review the evidence underlying the use of imiglucerase in Gaucher disease type 1

Evidence review

Data from clinical trials and Gaucher Registries were analyzed.

Conclusion

Imiglucerase has been prescribed and found to have an excellent efficacy and safety profile. We report herein the evidence-based data published for 26 years justifying the use of imiglucerase.

Recommendations for the use of eliglustat in the treatment of adults with Gaucher disease type 1 in the United States

In Gaucher disease, deficient activity of acid β-glucosidase results in accumulation of its substrates, glucosylceramide and glucosylsphingosine, within the lysosomes of cells primarily in the spleen, liver, bone marrow, and occasionally the lung. The multisystem disease is predominantly characterized by hepatosplenomegaly, anemia, thrombocytopenia, and skeletal disease. Enzyme replacement therapy with recombinant human acid β-glucosidase has been the first-line therapy for Gaucher disease type 1 for more than two decades. Eliglustat, a novel oral substrate reduction therapy, was recently approved in the United States and the European Union as a first-line treatment for adults with Gaucher disease type 1. Eliglustat inhibits glucosylceramide synthase, thereby decreasing production of the substrate glucosylceramide and reducing its accumulation. Although existing recommendations for the care of patients with Gaucher disease remain in effect, unique characteristics of eliglustat require additional investigation and monitoring. A panel of physicians with expertise in Gaucher disease and experience with eliglustat in the clinical trials provide guidance regarding the use of eliglustat, including considerations before starting therapy and monitoring of patients on eliglustat therapy.

[Pregnancy in Gaucher disease]

Gaucher disease is a lysosomal storage disorder due to deficiency of glucocerebrosidase. The association with pregnancy exposes the worsening of the disease and complications of pregnancy and puerperium. We report a case of pregnancy in a woman of 35 years, suffering from Gaucher disease type 1. Pregnancy had a favorable outcome. Complications occurred. They were kept under control. The outcome was favorable. The authors discuss the evolution of the disease during pregnancy and management of complications. They can occur during pregnancy, post-partum and breastfeeding. Support begins with preconception consultation. It involves finding and correcting the biological problems and deficiencies, and management of complications. Genetic counseling is important, it helps prevent inbreeding.

First experience with enzyme replacement therapy during pregnancy and lactation in Pompe disease

Enzyme replacement therapy (ERT) with alglucosidase alfa was registered as a treatment for Pompe disease in 2006. It is as yet unknown whether ERT can be safely applied during pregnancy and lactation. A primiparous 40-year-old woman diagnosed with Pompe disease continued receiving ERT during pregnancy and lactation. Before pregnancy, she had moderate limb-girdle weakness and used nocturnal ventilation. During pregnancy, her clinical condition remained fairly stable until the 25th gestational week. Thereafter she experienced more problems with mobility and respiration. Fetal growth was normal as monitored by regular ultrasound investigations. A healthy boy was born at a gestational age of 37 weeks and 5 days by elective Cesarean section. There were no maternal complications and the child developed normally. One year after delivery the mother's physical condition was similar as prior to her pregnancy. Pharmacokinetic studies following enzyme infusion showed that alglucosidase alfa was secreted into the breast milk. Activity levels in the milk (245 nmol/ml.h) peaked at 2.5h after the end of the infusion; which was 2h later than in the plasma (80 μmol/ml.h). Twenty-four hours after start of the infusion, the enzyme activity in the breast milk was back to the pre-infusion level. In this case report, the continuation of treatment with alglucosidase alfa during pregnancy and lactation has been safe for the mother and the child.