The number of clinical trials in Japan that aim to obtain regulatory approval for new drugs and devices has increased for adults, but not children. The following reasons have been proposed for this discrepancy: the wide range of ages from newborns to adolescents, requirements for many drug formulations, the difficulties associated with obtaining consent, and less profit for companies. The processes required to obtain regulatory approval for drugs and devices, particularly in the pediatric field, differ among Japan, Europe, and the United States (US). While clinical trials are not necessarily required for the development of new drugs or obtaining additional indications in Japan, laws in Europe and the US require clinical trials on children for newly developed drugs; however, pharmaceutical companies are entitled to a 6-mo extension for a patent when pediatric data are added to the attached documents for clinical trials. We herein discuss the current status of and issues associated with pediatric drug development, including clinical trials, in Japan as well as future perspectives.
Hypophosphatasia (HPP) is a rare bone disease caused by inactivating mutations in the ALPL gene, which encodes tissue-nonspecific alkaline phosphatase (TNSALP). Patients with HPP have varied clinical manifestations and are classified based on the age of onset and severity. Recently, enzyme replacement therapy using bone-targeted recombinant alkaline phosphatase (ALP) has been developed, leading to improvement in the prognosis of patients with life-threatening HPP. Considering these recent advances, clinical practice guidelines have been generated to provide physicians with guides for standard medical care for HPP and to support their clinical decisions. A task force was convened for this purpose, and twenty-one clinical questions (CQs) were formulated, addressing the issues of clinical manifestations and diagnosis (7 CQs) and those of management and treatment (14 CQs). A systematic literature search was conducted using PubMed/MEDLINE, and evidence-based recommendations were developed. The guidelines have been modified according to the evaluations and suggestions from the Clinical Guideline Committee of The Japanese Society for Pediatric Endocrinology (JSPE) and public comments obtained from the members of the JSPE and a Japanese HPP patient group, and then approved by the Board of Councils of the JSPE. We anticipate that the guidelines will be revised regularly and updated.
Achondroplasia (ACH) is a skeletal dysplasia that presents with limb shortening, short stature, and characteristic facial configuration. ACH is caused by mutations of the FGFR3 gene, leading to constantly activated FGFR3 and activation of its downstream intracellular signaling pathway. This results in the suppression of chondrocyte differentiation and proliferation, which in turn impairs endochondral ossification and causes short-limb short stature. ACH also causes characteristic clinical symptoms, including foramen magnum narrowing, ventricular enlargement, sleep apnea, upper airway stenosis, otitis media, a narrow thorax, spinal canal stenosis, spinal kyphosis, and deformities of the lower extremities. Although outside Japan, papers on health supervision are available, they are based on reports and questionnaire survey results. Considering the scarcity of high levels of evidence and clinical guidelines for patients with ACH, clinical practical guidelines have been developed to assist both healthcare professionals and patients in making appropriate decisions in specific clinical situations. Eleven clinical questions were established and a systematic literature search was conducted using PubMed/MEDLINE. Evidence-based recommendations were developed, and the guidelines describe the recommendations related to the clinical management of ACH. We anticipate that these clinical practice guidelines for ACH will be useful for healthcare professionals and patients alike.
An individual’s sexual phenotype is usually determined by the presence or absence of the Y chromosome in the embryo’s karyotype, however, due to abnormal X/Y terminal exchange through male meiosis, a few individuals develop male genitalia in the absence of the Y chromosome. This case report presents an adolescent referred to the Pediatric Endocrinology Unit due to bilateral gynecomastia. A diagnosis of hypergonadotropic hypogonadism was established and chromosomal analysis disclosed 46,XX karyotype, with the SRY gene locus found on one of his X chromosomes. A multidisciplinary approach, including psychological support and genetic counseling, is ideal for the management of these patients. Neoplastic transformation of the dysgenetic gonads has been described in several cases, and hence self-examinations and regular ultrasounds are commonly advised.