92. First steps towards determination of the most efficient and effective newbornscreening (NBS) approach for LSD

Dietrich Matern, Jean Lacey, Karen Sanders, Mark Magera, Giselle Bentz Pino, ElyseGrycki, Elisabeth Wooley, Kimiyo Raymond, Biochemical Genetics Lab, Department ofLaboratory Medicine, Mayo Clinic College of Medicine

Several methods for the detection of a few LSD in dried blood spots (DBS) havebeen described in recent years. To date, a tandem mass spectrometry (MS/MS)approach has found acceptance in several NBS programs and is supported by the CDCsNewborn Screening Quality Assurance Program (NSQAP) which provides calibratorsand QC samples. Our laboratory has implemented the MS/MS based assay for Pompe,Fabry, Gaucher, Krabbe, and Niemann-Pick A/B diseases and enzyme-specific fluoro-metric assays for Pompe, Fabry and Gaucher diseases. We aim to determine a NBSapproach for LSD that is characterized by highest sensitivity and specificity. A firststep towards this goal is the implementation and comparison of the various screeningmethods proposed. Here we report such comparison of the aforementioned methodsin DBS samples of confirmed cases of Pompe (n = 13), Fabry (n = 12 males, 7 females),and Gaucher (n = 13) diseases. Determination of alpha-glucosidase, alpha-galactosi-dase, and beta-glucosidase activities by both methods in normal controls (n = 125,123, and 74, respectively) revealed regression coefficients of 0.92, 0.69, and 0.80,respectively. Enzyme activities determined by both methods and compared againstnormal control ranges revealed abnormal results in all patients with confirmed diag-noses. Alpha-galactosidase activities for carrier females were higher than in affectedmales but below their respective control range.

This comparison indicates that both enzyme assays allow identification of affectedpatients and that the fluorometric methods can be used as second tier assays to confirmabnormal results of the multiplex MS/MS analysis, thereby improving NBS specificity.

doi:10.1016/j.ymgme.2009.10.109

93. A Phase2 clinical trial to assess the safety and tolerability of the pharmaco-logical chaperone AT 2101 in treatment-nave adult patients with type IGaucher disease

Atul Mehta, Derralynn Hughes, Eugene Schneider, Quinn Dinh, Royal Free & UniversityCollege Medical School, Amicus Therapeutics

Background: AT 2101 (afegostat tartrate) is an orally administered small moleculepharmacological chaperone designed to selectively bind and stabilize glucocerebro-sidase (GCase), thereby increasing GCase trafficking to the lysosome and cellularactivity. The first clinical trial of AT 2101 in Type 1 Gaucher disease (GD) was con-ducted in 30 participants at 11 U.S. sites. AT 2101 was generally well-tolerated atall doses evaluated with no reported serious adverse events. Leukocyte GCase activitywas increased in 20 of the 26 evaluable subjects, with higher doses of AT 2101 pro-ducing more consistent elevations of GCase. Treatment with AT 2101 for 4 weekswas not associated with changes in hematologic parameters or biological markersof disease progression in stable subjects with Type 1 GD who suspended enzymereplacement therapy (ERT) for 7 weeks. We now report preliminary results of the sec-ond clinical trial of AT 2101 in patients with Type 1 GD.

Study design: This was a randomized, open-label study to assess the safety andtolerability of AT 2101 in treatment-naive adult patients with Type 1 GD.

Objectives: (1) to evaluate the safety and tolerability of 2 dose regimens of orallyadministered AT 2101; (2) to assess pharmacodynamic (PD) effects of these 2 doseregimens.

Methods: The study consisted of a screening period of up to 21 days, followed byrandomization, a 24-week treatment period, and a 14-day post-treatment follow-upperiod. Study participants were randomized to one of two AT 2101 treatment cohorts:(1) one cycle of 225 mg once daily for 7 days on and 7 days off then continue on 3 dayson and 4 days off regimen for 22 weeks; (2) 225 mg once daily for 7 days on and 7 daysoff for 24 weeks. Patient Demographics and Baseline Characteristics: 19 patients wereenrolled across 10 study centers worldwide. Subjects average age was 43 years (range:17 years 10 mo to 69 years), 15 were males and 4 females, 18 out of 19 were Caucasian.The subjects relevant clinical characteristics at baseline were as follows: averagehemoglobin concentration was 13 g/dL (range: 11–15.9 g/dL), average platelet countwas 73 109/L (range: 41123 109/L), average spleen volume was 12 multiples of nor-mal (MN) (range: 3–64 MN), average liver volume was 1.5 MN (range: 1–3.6 MN).

Preliminary results and conclusions: Pending at time of abstract submission.

doi:10.1016/j.ymgme.2009.10.110

94. The UBDRS predicts rate of JCNL (CLN3) disease progression

Jonathan Mink, Jennifer M. Kwon, Frederick J. Marshall, Heather R. Adams, Paul G.Rothberg, Elisabeth A. deBlieck, Amy Vierhile, Nicole J. Newhouse, Erika J. Levy, ErikaF. Augustine, Denia Ramirez-Montealegre, University of Rochester, Rochester, NY, USA

We developed the Unified Batten Disease Rating Scale (UBDRS) to measure phys-ical, behavioral and functional capability domains in patients with juvenile neuronalceroid lipofuscinosis (JNCL), a neurodegenerative lysosomal storage disorder. Wehave evaluated the UBDRS in subjects with JNCL since 2002 during which the scaleand has been refined to improve reliability and validity. Now that therapies are beingproposed to prevent, slow, or reverse the course of JNCL, the UBDRS will play animportant role in assessing clinical outcomes in research trials.

We administered the UBDRS to nearly 100 patients with Batten disease over 8years. The majority of these subjects have CLN3 mutations and have had serial annualresearch evaluations. From these data, the rate of physical and motor decline has beencalculated in subjects with known CLN3 mutations. The rate of decline over time wasquantified using multivariate linear regression and repeated measures analysis.

Of 99 subjects, 82 had JNCL with known CLN3 mutations. Fourty-two subjectswere seen more than once at least annually. The UBDRS physical subscale showsdecline over time that proceeds at a quantifiable linear rate in the years following ini-tial onset of clinical symptoms. This decline correlates with functional capability andis not influenced by gender or CLN3 genotype.

The UBDRS is a reliable and valid instrument that measures clinical progression inJNCL. Our data support the use of the UBDRS to predict the rate of decline in juvenile-onset NCL (JNCL) in clinical trials.

doi:10.1016/j.ymgme.2009.10.111

95. Developmental and functional surveillance in preschool children with lyso-somal storage diseases

Michael Msalla, Duffner Patriciab, Nancy Lyona, Elsa Shapiroc, aWomen and ChildrensHospital, University of Chicago, Buffalo, NY, USA, bHunter James Kelly Research Institute,Center on Excellence in Bioinformatics, University of Chicago, Buffalo, NY, USA, cUniversityof Minnesota, Minneapolis, MN, USA

Background: New treatments for children with lysosomal storage diseases (LSD)are being developed and applied to treatment. However, there are several barriersin assessing their effectiveness.

Objective: (1) To develop a phone-based surveillance system for capturing health,developmental, and functional outcomes. (2) To use validated tools for assessinghealth and developmental status, behavior, and adaptive competencies in early child-hood. (3) Link these scores to standard neuropsychological testing of cognitive andadaptive skills at ages 2 and 5 years.

Methods: Four initial preschool cohorts will be enrolled. (1) Children with con-firmed Krabbe disease (2) Children with Metachromatic Leukodystrophy (3) Childrenwith mucopolysaccharidosis (MPS) Type I Parent/caregiver of our cohorts will beinterviewed every 6 months via phone when their child is between 6 and 72 months.The following standardized assessments will be used to measure the childs progressand family supports: Ages and Stages Questionnaires (ASQ); Warner Initial Develop-mental Evaluation of Adaptive and Functional Skills (WIDEAFS); Pediatric Evaluationof Disability Inventory Caregiver Assistance (PEDICA); Strengths and DifficultiesQuestionnaire; Health Status SF-12; Center for Epidemiologic Studies DepressionScale (CES-D); Support Function Scale (SFS); Family Activity Scale (FAS) Outcomeswill be analyzed using the following categories: (1) Children who received enzymereplacement by infusion. (2) Children who received stem cell transplantation. (3)Children who received specific metabolic therapies. (4) Children who received com-bination of attenuation 1 through 3 listed above. (5) Children with early onset Lyso-somal disorders who did not receive any of the above interventions.

doi:10.1016/j.ymgme.2009.10.112

96. Natural history and structural–functional relationships (SFR) in Fabrynephropathy (FN)

Behzad Najafianb, Marie-Claire Gublera, Chester Whitleyb, Einar Svarstadc, LeifBostadc, Michael Mauerb, aUniversit Ren Descartes, Hpital Necker-Enfants Malades AP-HP, Paris, France, bDepartment of Pediatrics, University of Minnesota, Minneapolis, MN,USA, cMedical Department, and Departments of Pediatrics, and Pathology, HauklandUniversity Hospital, Bergen, Norway

Background: Most male and about 20% of female Fabry patients eventually devel-op end stage renal disease (ESRD). However, pathophysiology of FN is not well-under-stood. SFR studies can lead to the discovery of FN progression predictors.

Aim: To study FN natural history and renal function and structure in 50–60 Fabrypatients with a broad range of age from childhood to adulthood before starting en-zyme replacement therapy.

Preliminary data: We have so far studies renal biopsies from 20 (male/female = 2/1) Fabry patients, age 4–44 years; Glomerular structural parameters, including vol-ume fraction of globotriaosylceramide (GL3) inclusions in podocytes [Vv(Inc/PC)],

Abstracts/Molecular Genetics and Metabolism 99 (2010) S8–S41 S27