ABSTRACT
Model-informed drug development (MIDD) refers to the application of various mathematical models in drug development, in order to facilitate the decision-making process. There have been common and mature applications of MIDD to address drug development and regulatory questions in interactional industries and advanced regulatory agencies, especially the US FDA. However, its application in innovative drug development is relatively rare in China. Representative case studies, clinical pharmacology review ex-periences, and relevant guidelines are reviewed in this article to present a preliminary discussion on the main applications of MIDD. Additionally, several suggestions for the application of MIDD in new drug development as well as general considerations for new drug registration are proposed in this paper, for the discussion or reference of industries and researchers.
ABSTRACT
Maternally inherited diabetes and deafness (MIDD) has been related to an A to G transition in the mitochondrial tRNA Leu (UUR) gene at the base pair 3243. This subtype of diabetes is characterized by maternal transmission, young age at onset and bilateral hearing impairment. Besides diabetes and deafness, the main diagnostic features, a wide range of multisystemic symptoms may be associated with the A3243G mutation. Organs that are most metabolically active, such as muscles, myocardium, retina, cochlea, kidney and brain are frequently affected. Gastrointestinal tract symptoms are also common in patients with mitochondrial disease and constipation and diarrhea are the most frequent manifestations. However, there are few prior reports of intestinal pseudo obstruction in MIDD patients. Here we report the case of a patient with MIDD associated with the mtDNA A3243G mutation who developed chronic intestinal pseudo obstruction, and the introduction of Coenzyme Q10 as adjunctive therapy led to a solution of the pseudo obstruction.
Diabetes mitocondrial ou diabetes e surdez de herança maternal (MIDD, acrônimo de maternally inherited diabetes and deafness) é freqüentemente associado à mutação mitocondrial A3243G. Esse subtipo de diabetes é caracterizado por transmissão materna, disacusia neuro-sensorial bilateral e idade precoce de aparecimento. Além do diabetes e da surdez, principais características diagnósticas, outros sintomas em diferentes órgãos podem também associar-se à mutação A3243G. Os órgãos que são metabolicamente mais ativos, tais como músculos, miocárdio, retina, cóclea, rim e cérebro, são freqüentemente afetados. Sintomas do trato gastrintestinal também são comuns em pacientes com doença mitocondrial, sendo diarréia e obstipação as manifestações mais freqüentes. Entretanto, há poucos relatos de pseudo-obstrução intestinal em portadores de diabetes mitocondrial. Este relato descreve o caso de uma paciente com diabetes mitocondrial que apresentou pseudo-obstrução intestinal e que com a introdução de coenzima Q10, como terapia adjunta, teve resolução o quadro.
Subject(s)
Female , Humans , Middle Aged , Diabetes Complications , Diabetes Mellitus , Deafness/complications , Intestinal Pseudo-Obstruction , Ubiquinone/analogs & derivatives , Vitamins/therapeutic use , DNA, Mitochondrial/genetics , Deafness/genetics , Diabetes Mellitus/genetics , Intestinal Pseudo-Obstruction/drug therapy , Intestinal Pseudo-Obstruction/genetics , Pedigree , Point Mutation/genetics , Ubiquinone/therapeutic useABSTRACT
The aim of the present study is to investigate the prevalence of ten described mitochondrial DNA (mtDNA) mutations in patients with type 2 diabetes, and search for new mutations in four mtDNA genes in a subgroup of patients with characteristics of maternally inherited diabetes and deafness (MIDD). These mutations were investigated in 407 type 2 diabetic patients without characteristics of mitochondrial diabetes ("classical" type 2 diabetes group) and in 38 type 2 diabetic patients with characteristics suggestive of MIDD. Through sequencing of four mtDNA genes in MIDD patients, we selected five others potentially pathogenic mutations that were also screened in the remaining patients. Overall, the frequency of the fifteen analyzed mutations was 36.84 percent in the MIDD group and 2.45 percent in the "classical" type 2 diabetes group (p < 0.001). In conclusion, our study reinforces the importance of mtDNA mutations in the pathogenesis of MIDD.
Os objetivos deste estudo foram investigar a prevalência de dez mutações conhecidas no DNA mitocondrial (mtDNA) em pacientes com diabetes tipo 2, e procurar por novas mutações em quatro genes mitocondriais em um subgrupo de pacientes com características de MIDD (Maternally Inherited Diabetes and Deafness). Estas mutações foram investigadas em 407 pacientes diabéticos tipo 2 sem características de diabetes mitocondrial (grupo de diabetes tipo 2 clássico) e em 38 pacientes com diabetes tipo 2 e com características sugestivas de MIDD. Através do seqüenciamento de quatro genes mitocondriais nos pacientes com MIDD, selecionou-se cinco outras mutações potencialmente patogênicas que também foram investigadas no restante dos pacientes. De uma forma geral, a freqüência total das 15 mutações analisadas foi de 36,8 por cento no grupo de pacientes com MIDD e de 2,4 por cento no grupo de diabetes tipo 2 clássico (p < 0,001). Em conclusão, nosso estudo reforça a importância de mutações mitocondriais na patogênese do MIDD.