Publications by authors named "Günther Metz"

8 Publications

  • Page 1 of 1

Real-World Clinical Experience With Idebenone in the Treatment of Leber Hereditary Optic Neuropathy.

J Neuroophthalmol 2020 12;40(4):558-565

Department of Neurology (CBC, OM, TK), Friedrich-Baur-Institute, University Hospital of the Ludwig-Maximilians-University, Munich, Germany; German Center for Neurodegenerative Diseases (DZNE) (CBC, TK), Munich, Germany; Department of Ophthalmology (BL, CP, FL, GR), University Hospital of the Ludwig-Maximilians-University Munich, Germany; New York Eye and Ear Infirmary of Mount Sinai (RB), New York, New York; Ophthalmology Department (SM), Waikato Hospital, Hamilton, New Zealand; Scheie Eye Institute (MAT), University of Pennsylvania, Philadelphia, Pennsylvania; Institut Català de Retina (LC), Barcelona, Spain; Augenklinik (CF), Universitätsklinikum Giessen, Giessen, Germany; University Hospital Southampton (CAH), Southampton, United Kingdom; McGovern Medical School (JAL), UTHealth, Houston, Texas; Department of Ophthalmology (GLT, KL, SJL), University Hospital and University of Zurich, Zurich, Switzerland; Neuro-ophthalmology Associates (GA), Ankara, Turkey; Manchester Centre for Genomic Medicine (GCMB), Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Sciences Centre, St Mary's Hospital, Manchester, United Kingdom; Division of Evolution and Genomic Sciences (GCMB), Neuroscience and Mental Health Domain, School of Health Sciences, Faculty of Biology, Medicines and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom; Ophthalmology Unit (CD), Hospital de Poniente, El Ejido, Almería, Spain; Save Sight Institute (CLF), University of Sydney, Sydney, Australia; Department of Pediatric Traumatology and Emergency Medicine (JJ), Wroclaw Medical University, Poland; Poland SPEKTRUM Ophthalmology Clinic (JJ), Wroclaw, Poland; University Hospital Ramon y Cajal (FJM-N), IRYCIS, Madrid, Spain; Emory University School of Medicine (NJN), Atlanta Georgia; Nuffield Dept Obstetrics and Gynaecology (JP), University of Oxford, The Women's Centre, Oxford, United Kingdom; Department of Ophthalmology (ES), East Kent Hospitals University Foundation Trust, United Kingdom; Neuro-Ophthalmology Division (PS), University of Colorado School of Medicine, Aurora, Colorado; Department of Neuroinflammation (ATT), Queen Square MS Centre, UCL Institute of Neurology, University College London, London, United Kingdom; Hospital Sant Joan de Déu Barcelona (MV), Barcelona, Spain; Eye Department (ALV), Greenlane Clinical Centre, Auckland, New Zealand; School of Optometry and Vision Sciences (MV), Cardiff University, Cardiff, United Kingdom; Department of Developmental Neurology (MZ), Poznan University of Medical Sciences, Poznan, Poland; Manchester Centre for Clinical Neuroscience (AZ), Salford Royal NHS Foundation Trust, Salford, United Kingdom; Neuro-ophthalmology Unit (MS, XL, GM) Santhera Pharmaceuticals, Pratteln, Switzerland; and Munich Cluster for Systems Neurology (SyNergy) (TK), Munich, Germany.

Background: Leber hereditary optic neuropathy (LHON) leads to bilateral central vision loss. In a clinical trial setting, idebenone has been shown to be safe and to provide a trend toward improved visual acuity, but long-term evidence of effectiveness in real-world clinical practice is sparse.

Methods: Open-label, multicenter, retrospective, noncontrolled analysis of long-term visual acuity and safety in 111 LHON patients treated with idebenone (900 mg/day) in an expanded access program. Eligible patients had a confirmed mitochondrial DNA mutation and had experienced the onset of symptoms (most recent eye) within 1 year before enrollment. Data on visual acuity and adverse events were collected as per normal clinical practice. Efficacy was assessed as the proportion of patients with either a clinically relevant recovery (CRR) or a clinically relevant stabilization (CRS) of visual acuity. In the case of CRR, time to and magnitude of recovery over the course of time were also assessed.

Results: At time of analysis, 87 patients had provided longitudinal efficacy data. Average treatment duration was 25.6 months. CRR was observed in 46.0% of patients. Analysis of treatment effect by duration showed that the proportion of patients with recovery and the magnitude of recovery increased with treatment duration. Average gain in best-corrected visual acuity for responders was 0.72 logarithm of the minimal angle of resolution (logMAR), equivalent to more than 7 lines on the Early Treatment Diabetic Retinopathy Study (ETDRS) chart. Furthermore, 50% of patients who had a visual acuity below 1.0 logMAR in at least one eye at initiation of treatment successfully maintained their vision below this threshold by last observation. Idebenone was well tolerated, with most adverse events classified as minor.

Conclusions: These data demonstrate the benefit of idebenone treatment in recovering lost vision and maintaining good residual vision in a real-world setting. Together, these findings indicate that idebenone treatment should be initiated early and be maintained more than 24 months to maximize efficacy. Safety results were consistent with the known safety profile of idebenone.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/WNO.0000000000001023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7657145PMC
December 2020

Rating disease progression of Friedreich's ataxia by the International Cooperative Ataxia Rating Scale: analysis of a 603-patient database.

Brain 2013 Jan;136(Pt 1):259-68

Santhera Pharmaceuticals, Hammerstrasse 49, CH-4410 Liestal, Switzerland.

The aim of this cross-sectional study was to analyse disease progression in Friedreich's ataxia as measured by the International Cooperative Ataxia Rating Scale. Single ratings from 603 patients with Friedreich's ataxia were analysed as a function of disease duration, age of onset and GAA repeat lengths. The relative contribution of items and subscales to the total score was studied as a function of disease progression. In addition, the scaling properties were assessed using standard statistical measures. Average total scale progression per year depends on the age of disease onset, the time since diagnosis and the GAA repeat length. The age of onset inversely correlates with increased GAA repeat length. For patients with an age of onset ≤14 years associated with a longer repeat length, the average yearly rate of decline was 2.5 ± 0.18 points in the total International Cooperative Ataxia Rating Scale for the first 20 years of disease duration, whereas patients with a later onset progress more slowly (1.8 ± 0.27 points/year). Ceiling effects in posture, gait and lower limb scale items lead to a reduced sensitivity of the scale in the severely affected population with a total score of >60 points. Psychometric scaling analysis shows generally favourable properties for the total scale, but the subscale grouping could be improved. This cross-sectional study provides a detailed characterization of the International Cooperative Ataxia Rating Scale. The analysis further provides rates of change separated for patients with early and late disease onset, which is driven by the GAA repeat length. Differences in the subscale dynamics merit consideration in the design of future clinical trials applying this scale as a neurological assessment instrument in Friedreich's ataxia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/brain/aws309DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3624678PMC
January 2013

A randomized placebo-controlled trial of idebenone in Leber's hereditary optic neuropathy.

Brain 2011 Sep 25;134(Pt 9):2677-86. Epub 2011 Jul 25.

Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, NE1 3BZ, UK.

Major advances in understanding the pathogenesis of inherited metabolic disease caused by mitochondrial DNA mutations have yet to translate into treatments of proven efficacy. Leber's hereditary optic neuropathy is the most common mitochondrial DNA disorder causing irreversible blindness in young adult life. Anecdotal reports support the use of idebenone in Leber's hereditary optic neuropathy, but this has not been evaluated in a randomized controlled trial. We conducted a 24-week multi-centre double-blind, randomized, placebo-controlled trial in 85 patients with Leber's hereditary optic neuropathy due to m.3460G>A, m.11778G>A, and m.14484T>C or mitochondrial DNA mutations. The active drug was idebenone 900 mg/day. The primary end-point was the best recovery in visual acuity. The main secondary end-point was the change in best visual acuity. Other secondary end-points were changes in visual acuity of the best eye at baseline and changes in visual acuity for both eyes in each patient. Colour-contrast sensitivity and retinal nerve fibre layer thickness were measured in subgroups. Idebenone was safe and well tolerated. The primary end-point did not reach statistical significance in the intention to treat population. However, post hoc interaction analysis showed a different response to idebenone in patients with discordant visual acuities at baseline; in these patients, all secondary end-points were significantly different between the idebenone and placebo groups. This first randomized controlled trial in the mitochondrial disorder, Leber's hereditary optic neuropathy, provides evidence that patients with discordant visual acuities are the most likely to benefit from idebenone treatment, which is safe and well tolerated.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/brain/awr170DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3170530PMC
September 2011

Effect of calpain and proteasome inhibition on Ca2+-dependent proteolysis and muscle histopathology in the mdx mouse.

FASEB J 2008 Dec 26;22(12):4190-200. Epub 2008 Aug 26.

Santhera Pharmaceuticals (Switzerland) Ltd, Hammerstrasse 47, CH-4410 Liestal, Switzerland.

Dystrophin deficiency is the underlying molecular cause of progressive muscle weakness observed in Duchenne muscular dystrophy (DMD). Loss of functional dystrophin leads to elevated levels of intracellular Ca(2+), a key step in the cellular pathology of DMD. The cysteine protease calpain is activated in dystrophin-deficient muscle, and its inhibition is regarded as a potential therapeutic approach. In addition, previous work has shown that the ubiquitin-proteasome system also contributes to muscle protein breakdown in dystrophic muscle and, therefore, also qualifies as a potential target for therapeutic intervention in DMD. The relative contribution of calpain- and proteasome-mediated proteolysis induced by increased Ca(2+) levels was characterized in cultured muscle cells and revealed initial Ca(2+) influx-dependent calpain activity and subsequent Ca(2+)-independent activity of the ubiquitin-proteasome system. We then set out to optimize novel small-molecule inhibitors that inhibit both calpain as well as the 20S proteasome in a cellular system with impaired Ca(2+) homeostasis. On administration of such inhibitors to mdx mice, quantitative histological parameters improved significantly, in particular with compounds strongly inhibiting the 20S proteasome. To investigate the role of calpain inhibition without interfering with the ubiquitin-proteasome system, we crossed mdx mice with transgenic mice, overexpressing the endogenous calpain inhibitor calpastatin. Although our data show that proteolysis by calpain is strongly inhibited in the transgenic mdx mouse, this calpain inhibition did not ameliorate muscle histology. Our results indicate that inhibition of the proteasome rather than calpain is required for histological improvement of dystrophin-deficient muscle. In conclusion, we have identified novel proteasome inhibitors that qualify as potential candidates for pharmacological intervention in muscular dystrophy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1096/fj.07-099036DOI Listing
December 2008

Homology models of dipeptidyl peptidases 8 and 9 with a focus on loop predictions near the active site.

Proteins 2007 Jan;66(1):160-71

Santhera Pharmaceuticals (Switzerland) Ltd., Hammerstrasse 47, 4410 Liestal, Switzerland.

Dipeptidyl peptidase 4 (DP4) inhibitors are currently under intensive investigation in late-stage clinical trials as a treatment for type II diabetes. Lack of selectivity toward the related enzymes DP8 and DP9 has recently emerged as a possible source of drug-induced toxicity. Unlike DP4, X-ray structures of DP8 and DP9 are not yet available. As an aid to understanding the structural basis for selectivity, the authors have constructed homology models of DP8 and DP9 based on the X-ray coordinates of DP4. Accurate sequence alignment reveals common structural features indicative for a well-preserved overall fold comprising two domains, namely, a hydrolase domain and a so-called beta-propeller, which together form the active site deeply buried within the protein. The conformation of two loops inside this deep cavity is particularly relevant for the active sites. The authors used a published protocol for loop prediction based on conformational sampling and energy analysis to generate plausible solutions for these two loops. The predictive power of the approach was successfully evaluated for the template protein DP4 and two additional known structures from the same protein family, namely, FAP and DPX. The authors also show that inclusion of the covalent ligand NVP-728 greatly enhances the refinement. Based on the established evaluation protocol, the corresponding loops of DP8 and DP9 were predicted and the resulting active sites were compared with DP4. In particular, the authors conclude that differences in the P2-pocket are relevant for the design of selective DP4 inhibitors. The loss of key interactions in DP8 and DP9 as predicted from their models is consistent with the selectivity profile of the DP4 clinical candidate MK-431.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/prot.21138DOI Listing
January 2007

The reversed binding of beta-phenethylamine inhibitors of DPP-IV: X-ray structures and properties of novel fragment and elaborated inhibitors.

Bioorg Med Chem Lett 2006 Mar 11;16(6):1744-8. Epub 2006 Jan 11.

Medicinal Chemistry, Santhera Pharmaceuticals, Im Neuenheimer Feld 518-519, D-69120 Heidelberg, Germany.

The co-crystal structure of beta-phenethylamine fragment inhibitor 5 bound to DPP-IV revealed that the phenyl ring occupied the proline pocket of the enzyme. This finding provided the basis for a general hypothesis of a reverse binding mode for beta-phenethylamine-based DPP-IV inhibitors. Novel inhibitor design concepts that obviate substrate-like structure-activity relationships (SAR) were thereby enabled, and novel, potent inhibitors were discovered.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bmcl.2005.11.103DOI Listing
March 2006

In silico fragment-based discovery of DPP-IV S1 pocket binders.

Bioorg Med Chem Lett 2006 Mar;16(5):1405-9

Computational Discovery, Santhera Pharmaceuticals, Im Neuenheimer Feld 518-519, 69120 Heidelberg, Germany.

Dipeptidyl peptidase IV is a clinically validated target for type-2 diabetes and belongs to a family of peptidases with a quite unique post-proline cleavage specificity. Known inhibitors contain a limited number of molecular anchors occupying the small prototypical S1 pocket. A virtual screening approach for such S1-binding fragments was carried out using FlexX docking to evaluate its potential to confirm known and find novel compounds. Several low molecular weight inhibitors exhibiting activities in the micromolar range could be identified as starting points for structure-based design.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bmcl.2005.11.038DOI Listing
March 2006

Custom chemical microarray production and affinity fingerprinting for the S1 pocket of factor VIIa.

Anal Biochem 2004 Dec;335(1):50-7

Graffinity Pharmaceuticals AG, Im Neuenheimer Feld 518-519, D-69120 Heidelberg, Germany.

The goal of this study was to explore the applicability of surface plasmon resonance (SPR)-based fragment screening to identify compounds that bind to factor VIIa (FVIIa). Based on pharmacophore models virtual screening approaches, we selected fragments anticipated to have a reasonable chance of binding to the S1-binding pocket of FVIIa and immobilized these compounds on microarrays. In affinity fingerprinting experiments, a number of compounds were identified to be specifically interacting with FVIIa and shown to fall into four structural classes. The results demonstrate that the chemical microarray technology platform using SPR detection generates unique chemobiological information that is useful for de novo discovery and lead development and allows the detection of weak interactions with ligands of low molecular weight.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ab.2004.08.033DOI Listing
December 2004