European Human Genetics Conference 2007 June 16 – 19, 2007 ...

Therapy for genetic disease
P1405. Safety of agalsidase alfa enzyme replacement therapy in
a cohort of 1329 patients in FOS - the Fabry Outcome Survey
G. Sunder-Plassmann 1 , M. Beck 2 , J. Clarke 3 , A. Linhart 4 , A. Mehta, on behalf
of the FOS Investigators 5 ;
1 Division of Nephrology and Dialysis, Vienna, Austria, 2 University of Mainz,
Mainz, Germany, 3 Hospital for Sick Children, Toronto, ON, Canada, 4 Charles
University, Prague, Czech Republic, 5 Royal Free Hospital, London, United
Kingdom.
Background: FOS was established in 2001 to monitor the long-term
efficacy and safety of enzyme replacement therapy (ERT) with agalsidase
alfa in patients with Fabry disease. This is a rare X-linked lysosomal
storage disorder that results in progressive accumulation of the
enzyme substrate globotriaosylceramide in cells throughout the body,
leading to organ failure and premature death. The FOS database has
recently been expanded to include patients from non-European countries.
The present analysis provides demographic and safety data from
a total cohort of 1329 patients enrolled in FOS as of January 2007.
Methods: The FOS database was analysed in terms of patient demography
and safety of ERT.
Results: The 1329 patients in FOS have been recruited from 109 centres
in 19 countries. Of those enrolled, 828 (62%) are receiving ERT.
Approximately equal numbers of males and females are on treatment,
and 154 (18.6%) are receiving treatment at home. More than 25 men
have been given agalsidase alfa for at least 6 years, and > 50% of the
200 children in FOS are receiving ERT. Mild infusion reactions are the
most common drug-related adverse events, reported in 11% of males
and 4% of females and representing < 1% of the infusions given. Most
reactions occurred between 3 and 6 months after the start of treatment
and then declined in frequency. No IgE antibodies have been
detected.
Conclusion: Long-term safety data from a large cohort of male, female
and paediatric patients in FOS confirm that ERT with agalsidase alfa
is very well tolerated.
P1406. A Gaucher disease ex vivo response study: the
pharmacological chaperone AT2101 increases levels of
glucocerebrosidase in patient-derived cells
C. W. Pine1 , B. E. Ranes1 , F. Insinga1 , K. Ludwig1 , G. A. Grabowski2 , N. J.
Weinreb3 , G. M. Pastores4 , D. Gruskin5 , P. Kaplan6 , H. Do1 , D. J. Lockhart1 , B.
A. Wustman1 ;
1 2 Amicus Therapeutics, Cranbury, NJ, United States, Division of Human Genetics,
Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United
States, 3University Research Foundation for Lysosomal Storage Diseases Inc,
Northwest Oncology Hematology Associates, Coral Springs, FL, United States,
4Departments of Neurology and Pediatrics, New York University School of
Medicine, New York, NY, United States, 5Departments of Human Genetics and
Pediatrics, Emory University School of Medicine, Atlanta, GA, United States,
6Section of Metabolic Diseases, Children’s Hospital of Philadelphia, University
of Pennsylvania School of Medicine, Philadelphia, PA, United States.
Gaucher disease (GD) is caused by a deficiency of lysosomal glucocerebrosidase
(GCase). Deficient GCase activity leads to symptoms such
as anemia, thrombocytopenia, hepatosplenomegaly, bone necrosis,
infarcts and osteoporosis, and in some cases, neuropathic disease.
To evaluate the effects of a pharmacological chaperone, AT2101, on
mutant GCase levels, we conducted an ex vivo response study using
macrophages and EBV-transformed lymphoblasts derived from peripheral
leukocytes. Plasma was also screened for potential biomarkers
associated with inflammation, bone metabolism, multiple myeloma
and neurodegeneration. An interim analysis was conducted on samples
from 40 patients enrolled at 5 sites in the United States. Results:
The study included 21 males and 18 females with type I GD, and one
male with type III GD. Patients ranged in age from 7 to 83 years, 38
of 40 patients were receiving enzyme replacement therapy (ERT) and
blood was drawn prior to ERT infusion. Analysis of 40 potential markers
in plasma showed elevated TRACP 5b, PARC, IL-8, IL-17, VEGF,
MIP-1α and α-synuclein and reduced bone-specific alkaline phosphatase
levels in most patients. Macrophages were successfully derived
from 34 of 40 patients, of which 32 demonstrated a dose-dependent
increase in GCase levels (average = 2.8-fold, range = 1.5- to 6.5-fold)
when treated with AT2101 (5 days). Similar results were observed for
5 additional patient-derived lymphoblast cell lines. AT2101 significantly
increased GCase levels in cells from patients with different genotypes
including N370S/N370S (n=11), N370S/L444P (n=8), N370S/84insG
(n=11), N370S/R163X, N370S/Y212H, L444P/del 136T, L444P/F216Y,
L444P/L174F, G202R/R463C, and K79N/complex B exon 9/10 (type
III GD).
P1407. Hyperbranched polylysines as vehicles for gene delivery
into eucaryotic cells
A. A. Egorova 1 , A. V. Kiselev 2,1 , P. L. Il’ina 1 , V. Y. Aksenova 1 , A. N. Baranov 2 , V.
S. Baranov 2 ;
1 Saint-Petersburg State University, Saint-Petersburg, Russian Federation, 2 Ott’s
Institute for Obstetrics and Gynecology, Saint-Petersburg, Russian Federation.
Efficient gene delivery into eucaryotic cells is an extremely critical step
in gene therapy. Development of new non-viral DNA vectors seems to
be a perspective approach for effective gene delivery into cells. This
study was confined to the groups of hyperbranched polylysine vehicles
(spLLs). Hyperbranched polylysine with its arginine or histidine
surface modified derivatives was studied. Surface lysine/arginine or
histidine ratio was 1/1 or 9/1. All vehicles were studied for their capacity
to bind DNA and provide protection of plasmid DNA from nuclease
degradation. Beta-galactosidase gene expression in HeLa cells
indicated transfectional capacity of tested vehicles. All spLLs proved
their capacity to condense and protect plasmid DNA. Transfectional
capacity of arginine-modified spLLs had no distinguishable difference
from that of unmodified hyperbranched polylysine. Histidine-modified
polylysine compounds showed 7-20-fold increase of transfectional activity
in comparison with unmodified vehicle. Transfectional activity of
histidine-modified polylysines was not affected by glycerol treatment.
Thus histidine-modified spLLs were found out to provide more effective
DNA delivery into cells, compared to arginine-modified spLLs. We
suggest that modification of polylysine surface with histidine results
in increase of endosomolytic ability and augmented transfectional
activity. Inclusion of endosomolytic peptide JTS-1 into DNA/histidinemodified
spLLs complexes resulted in 4-fold increase of transfection
efficiency. The level of transfectional activity was comparable to that
of PAMAM-dendrimer Polyfect. The results demonstrate that polymer
surface modification with histidine might be perspective for development
of new effective gene delivery vehicles on the basis of hyperbranched
polylysines. This work was supported with grants of CRDF
(ST-012) and RFBR (06-04-08338).
P1408. Miglustat in Gaucher Disease Type 3
A. Vellodi 1 , C. Harris 2 , C. DeVile 3 , E. Davies 1 , E. Fitzgibbon 3 , L. Abel 4 , P. Campbell
2 , N. van Schaik 5 , W. Benko 3 , M. Timmons 3 , R. Schiffmann 3 ;
1 Great Ormond Street Hospital for Sick Children, London, United Kingdom,
2 University of Plymouth, Plymouth, United Kingdom, 3 National Institutes of
Health, Bethesda, MD, United States, 4 University of Melbourne, Melbourne,
Australia, 5 Academic Medical Centre, Amsterdam, The Netherlands.
Thirty patients (29 on ERT, one BMT) were randomized 2:1 to receive
for 12 months either miglustat 200 mg t.i.d. or no treatment. All enrolled
patients in the 12-month extension phase received miglustat.
Of the 30 patients who completed the first year of treatment, 28 entered
the extension study. Mean age (SD) was 10.2 (4.8) years (60%
female). The median exposure to miglustat was 729 days (6-802 days).
The prevalence and severity of the clinical manifestations were heterogeneous.
Comparison of 24 months versus 12 months of treatment did
not show a significant difference in vertical saccadic eye movement
velocity changes, the primary endpoint. Organ volumes and haematological
parameters were stable. A decrease in chitotriosidase levels
and an increase in pulmonary FVC were observed in some patients.
The most frequently reported adverse events (AEs) were diarrhoea
(72%), tremor (38%) and abdominal pain (34%). Diarrhoea was mild
and its frequency decreased over time. None of the previous AEs led
to study discontinuation. One patient had a confirmed polyneuropathy
and withdrew from the study and 3 had sub-clinical neuropathy (1
poly- and 2 mono-neuropathy); one of the latter was included in the no
treatment group. There were no deaths.
This 24-month miglustat trial in GD3 patients did not show an effect
on the neurological endpoints assessed, but some effects on systemic
disease parameters and lung function were observed. The tolerability
profile of miglustat at 200 mg t.i.d. was comparable to that reported
with the approved dose for GD1 (100 mg t.i.d.).