What the Orphan Drug Act has done lately for children with rare diseases: a 10-year analysis

Generic orphan drug substitution: a critical analysis of global practices and Saudi Arabia's perspective

In an era of cost pressure, substituting generic drugs represents one of the main cost-containment strategies of healthcare systems. Despite the obvious financial benefits, in a minority of cases, substitution may require caution or even be contraindicated. In most jurisdictions, to obtain approval, the bioequivalence of generic products with the brand-name equivalent needs to be shown via bioavailability studies in healthy subjects. Rare diseases, defined as medical conditions with a low prevalence, are a group of heterogenous diseases that are typically severe, disabling, progressive, degenerative, and life-threatening or chronically debilitating, and disproportionally affect the very young and elderly. Despite these unique features of rare diseases, generic bioequivalence studies are typically carried out with single doses and exclude children or the elderly. Furthermore, the excipients and manufacturing processes for generic/biosimilar products can differ from the brand products which may affect the shelf-life of the product, its appearance, smell, taste, bioavailability, safety and potency. This may result in approval of generics/biosimilars which are not bioequivalent/comparable in their target population or that meet bioequivalence but not therapeutic equivalence criteria. Another concern relates to the interchangeability of generics and biosimilars which cannot be guaranteed due to the phenomenon of biocreep. This review summarizes potential concerns with generic substitution of orphan drugs and discusses potentially problematic cases including narrow therapeutic index drugs or critical conditions where therapeutic failure could lead to serious complications or even death. Finally, we put forward the need for refining regulatory frameworks, with emphasis on Saudi Arabia, for generic substitution and recent efforts toward this direction.

Analysis of the first ten years of FDA's rare pediatric disease priority review voucher program: designations, diseases, and drug development

BACKGROUND

The Rare Pediatric Disease (RPD) Priority Review Voucher (PRV) Program was enacted in 2012 to support the development of new products for children. Prior to requesting a voucher, applicants can request RPD designation, which confirms their product treats or prevents a rare disease in which the serious manifestations primarily affect children. This study describes the trends and characteristics of these designations. Details of RPD designations are not publicly disclosable; this research represents the first analysis of the RPD designation component of the program.

RESULTS

We used an internal US Food and Drug Administration database to analyze all RPD designations between 2013 and 2022. Multiple characteristics were analyzed, including the diseases targeted by RPD designation, whether the product targeted a neonatal disease, product type (drug/biologic), and the level of evidence (preclinical/clinical) to support designation. There were 569 RPD designations during the study period. The top therapeutic areas were neurology (26%, n = 149), metabolism (23%, n = 131), oncology (18%, n = 105). The top diseases targeted by RPD designation were Duchenne muscular dystrophy, neuroblastoma, and sickle cell disease. Neonatology products represented 6% (n = 33), over half were for drug products and 38% were supported by clinical data.

CONCLUSIONS

The RPD PRV program was created to encourage development of new products for children. The results of this study establish that a wide range of diseases have seen development-from rare pediatric cancers to rare genetic disorders. Continued support of product development for children with rare diseases is needed to find treatments for all children with unmet needs.

Policy analysis in the field of rare diseases in China: a combined study of content analysis and Bibliometrics analysis

Introduction

The Chinese government has made significant strides in addressing the needs of individuals affected by rare diseases in recent years. This paper aims to provide a comprehensive analysis of national rare disease policies in China from 2009 to 2022, using a mixed-methods approach.

Methods

A two-dimensional analytical framework, which includes policy tools and policy themes, is introduced to analyze the rare disease policies comprehensively. Drawing on the policy tools theory proposed by Rothwell and Zegveld, this paper evaluates the tools used in rare disease policies. Co-word analyses and network analyses are employed to identify key themes in rare disease policies and collaboration among government departments.

Results

The rare disease policy landscape in China is undergoing rapid growth, with an increasing number of government departments involved in policy formulation. However, further collaboration between departments is needed to strengthen these policies. Environment-based and supply-based tools are preferred in rare disease policies. The policy themes can be grouped into four categories: (1) Registration, Approval and Supply of Rare Disease Drugs, (2) Construction of Diagnosis and Treatment System for Rare Diseases, (3) Development and Genericization of Rare Disease Drugs, and (4) Social Security for Patients with Rare Diseases.

Discussion

The study provides valuable insights into the current state of rare disease policies in China and offers suggestions for policy improvement. The results show that the Chinese government has made efforts to address the needs of individuals affected by rare diseases, but there is still room for improvement. The collaboration between government departments needs to be strengthened to achieve better rare disease policies. The findings of this study have implications for other countries with similar healthcare systems and can contribute to a better understanding of the impact of rare disease policies on public health.

Using four decades of FDA orphan drug designations to describe trends in rare disease drug development: substantial growth seen in development of drugs for rare oncologic, neurologic, and pediatric-onset diseases

BACKGROUND

Orphan drug designations are a useful proxy to investigate trends in rare disease drug development. Drug developers must receive a designation before they are eligible for the economic incentives of the Orphan Drug Act in the United States. We created a database of all orphan drugs designated between 1983 and 2019 that included numerous drug characteristics, including therapeutic area. In addition, we constructed a "broad disease" categorization of designations as an alternative to therapeutic area, based on disease etiology and age of onset rather than organ system. By looking at the pattern of orphan drug designations over the past four decades, this analysis studied the impact of the evolving rare disease drug development landscape and considers the future of rare disease therapies over the coming decades.

RESULTS

Between 1983 and 2019, a total of 5099 drugs and biologics received orphan drug designation. Designations more than doubled between the 1980s and 1990s, almost doubled between the 1990s and 2000s, and almost tripled in number between the 2000s and 2010s. The top three therapeutic areas represented in the orphan drug designations were: oncology (1910, 37%), neurology (674, 13%), and infectious diseases (436, 9%). The broad disease categorization found that the proportion of designations for pediatric-onset diseases has increased in the most recent decade to 27%.

CONCLUSIONS

Analysis of the last four decades of orphan drug designation indicates seismic shifts have occurred in the rare disease drug development space. The number of designations granted more than quadrupled between the 1990s and 2010s. While these substantial increases led to growth in the absolute number of designations within all therapeutic areas (bar one) and broad disease categories, the relative proportions have seen considerable change over time. In the most recent decade, there have been notable increases in the proportion of drugs in oncology, pediatric-onset diseases, and neurologic disorders. The dramatic rise in overall orphan designations over the past four decades suggests we may continue to see an upward trajectory in designations leading to an increased number of approvals for drugs and biologics designed specifically for diagnosing, preventing, and treating rare diseases in the coming decades.

Market Exclusivity for Drugs with Multiple Orphan Approvals (1983-2017) and Associated Budget Impact in the US

OBJECTIVES

The Orphan Drug Act extends exclusivity of branded drugs by 7 years for each rare disease approval. By extending market exclusivity, manufacturers can forestall generic competition. We determined the prevalence of drugs with multiple orphan approvals, the duration for which manufacturers are able to maintain exclusivity using this mechanism, and the budget impact of these additional exclusivity periods on US spending on orphan drugs.

METHODS

We analyzed a retrospective cohort of US orphan drug approvals filed between 1983 and 2017. Drug costs throughout this time period were measured using IQVIA claims data. We estimated additional years of exclusivity per drug per orphan approval using mixed-effects negative binomial regression. The budget impact analyzed potential cost-savings for exclusivity periods greater than 7 years after the initial orphan approval based on potential price reductions from the introduction of biosimilar/generic competition.

RESULTS

A total of 432 branded drugs were approved for 615 orphan indications, of which 108 had multiple indications. Market exclusivity, beyond the initial 7 years, increased by 4.7 years with two orphan approvals, and there were 3.1-, 2.7-, and 2.9-year extensions for three, four, and five approvals, respectively (p < 0.05). Drugs with five approvals averaged 13.4 additional years of exclusivity. Sixteen drugs had exclusivity periods extending at least 1 decade beyond the original exclusivity period. The potential budget impact of additional exclusivity was estimated at US$591 billion for 7 years following the end of the first approval.

CONCLUSIONS

Multiple blockbuster drugs have received exclusivity of > 10 years through the Orphan Drug Act, thereby delaying rare disease cohorts' access to generic/biosimilar equivalents.

Pediatric Orphan Drug Indications: 2010-2018

BACKGROUND

Orphan drug development is crucial for children, who are disproportionately affected by rare diseases. Data are lacking on the number, nature, and benefit of recently approved pediatric orphan indications.

METHODS

We classified the 402 orphan indications the US Food and Drug Administration approved between 2010 and 2018 as "pediatric" if they were approved for children only or targeted pediatric diseases. We determined the number of unique diseases targeted by pediatric orphan indications and calculated the proportion that were for (1) novel drugs, (2) non-novel drugs approved to treat ≥1 common disease, and (3) non-novel drugs approved only to treat rare diseases. Among pediatric orphan indications eligible for US Food and Drug Administration breakthrough designation (granted to drugs potentially representing major therapeutic advances), we calculated the proportion receiving this designation.

RESULTS

Of the 402 orphan indications, 136 (33.8%) were pediatric. These 136 indications targeted 87 unique diseases; 21 diseases were targeted by ≥1 indication. Of the 136 pediatric orphan indications, 60 (44.1%) were for novel drugs, 45 (33.1%) were for non-novel drugs approved to treat ≥1 common disease, and 31 (22.8%) were for non-novel drugs approved only to treat rare diseases. Among 97 indications eligible for breakthrough designation, 20 (20.6%) received this designation.

CONCLUSIONS

Recent orphan drug development has increased the availability of treatments for pediatric rare diseases. Most pediatric orphan indications expanded use of existing drugs, and many targeted the same disease. Some indications may represent breakthroughs, but substantial unmet need for treatments remains for most pediatric rare diseases.

The third generation sequencing: the advanced approach to genetic diseases

Genomic sequencing technologies have revolutionized mutation detection of the genetic diseases in the past few years. In recent years, the third generation sequencing (TGS) has been gaining insight into more genetic diseases owing to the single molecular and real time sequencing technology. This paper reviews the genomic sequencing revolutionary history first and then focuses on the genetic diseases discovered through the TGS and the clinical effects of the TGS, which is followed by the discussion of the improvement in the bioinformatic analysis for the TGS and its limitations. In summary, the TGS has been enhancing the diagnostic accuracy of genetic diseases in molecular level as well as paving a new way for basic researches and therapies.

Developing interactions with industry in rare diseases: lessons learned and continuing challenges

The National Institutes of Health (NIH) established the Rare Diseases Clinical Research Network to address the unique challenges of performing research on rare diseases. The Urea Cycle Disorders Consortium (UCDC) was one of the original ten consortia established. The UCDC represents a unique partnership among clinicians, patients, and the NIH with a primary goal of increasing the development of therapeutics that improve patient outcomes for persons affected with a UCD. Based in part on financial incentives associated with the Orphan Drug Act biopharmaceutical and investment entities have an intense interest in engaging with research consortia like the UCDC, which have compiled potentially valuable longitudinal data characterizing outcomes in a relatively large number of affected individuals. We describe the UCDC experience and the bases for evaluating partnerships with such private entities. We review early industry interactions, the development of policies and procedures, and describe the establishment of an Industry Relations Committee, including guiding principles. Challenges encountered, particularly in the transition when products are approved, and potential solutions are discussed. By building a framework for industry partnerships that guides us in resolving inevitable challenges, we can enthusiastically pursue novel and promising collaborations that can lead to breakthroughs in therapeutic interventions for patients.

Generic Substitution of Orphan Drugs for the Treatment of Rare Diseases: Exploring the Potential Challenges

Generic drugs are important components of measures introduced by healthcare regulatory authorities to reduce treatment costs. In most patients and conditions the switch from a branded drug to its generic counterpart is performed with no major complications. However, evidence from complex diseases suggests that generic substitution requires careful evaluation in some settings and that current bioequivalence criteria may not always be adequate for establishing the interchangeability of branded and generic products. Rare diseases, also called orphan diseases, are a group of heterogeneous diseases that share important characteristics: in addition to their scarcity, most are severe, chronic, highly debilitating, and often present in early childhood. Finding a treatment for a rare disease is challenging. Thanks to incentives that encourage research and development programs in rare diseases, several orphan drugs are currently available. The elevated cost of orphan drugs is a highly debated issue and a cause of limited access to treatment for many patients. As patent protection and the exclusivity period of several orphan drugs will expire soon, generic versions of orphan drugs should reach the market shortly, with great expectations about their impact on the economic burden of rare diseases. However, consistent with other complex diseases, generic substitution may require thoughtful considerations and may be even contraindicated in some rare conditions. This article provides an overview of rare disease characteristics, reviews reports of problematic generic substitution, and discusses why generic substitution of orphan drugs may be challenging and should be undertaken carefully in rare disease patients.

Comparative analysis of the scope of European Union paediatric investigation plans with corresponding orphan designations

BACKGROUND

Market forces may not be sufficient to stimulate research and development of medicines for small patient populations, such as children and patients with rare diseases. Both the European Union Orphan and Paediatric Regulations were introduced to address the unmet public health needs of these smaller patient populations through the use of incentives, rewards and obligations. Developers for new medicines for rare diseases must agree a paediatric investigation plan (PIP) or waiver with the European Medicines Agency's (EMA) Paediatric Committee (PDCO), and can also apply for an orphan designation (OD) from the EMA's Committee of Orphan Medicinal Products (COMP). The scope of both the OD and the PIP (or waiver) is defined by the agreed condition.

OBJECTIVES

The aim of this study was to analyse the approach of PDCO and COMP in defining the appropriate condition for a PIP or OD, respectively, in order to investigate potential challenges in the paediatric development of orphan medicines which have to meet the requirements of both legislations.

METHODS

A comparative analysis of PIP conditions and OD conditions was performed for medicines that have been reviewed by both Committees.

RESULTS

We found that in the substantial majority of cases there is no divergence between the conclusions of COMP and PDCO with regard to the condition for which a medicine is to be developed.

CONCLUSION

These findings demonstrate that a collaborative approach allows both Regulations to work synergistically to foster pharmaceutical development for rare diseases in childhood.

Enhancing the Pediatric Drug Development Framework to Deliver Better Pediatric Therapies Tomorrow

Health care professionals involved in the clinical management of children have long appreciated the limited number of therapies suitably evaluated for their optimal use in the pediatric population. In the past century, advances in regulatory policy significantly evolved adult drug evaluation. The scarcity of available patient populations, practical complexities of drug development research, and minimal financial returns have hampered pharmaceutical investment in the study of therapies for children. More recently, pediatric policy and legislation in the United States and Europe have instituted a system of obligations and incentives to stimulate investment in pediatric drug development. These initiatives, in conjunction with a more sophisticated process of drug discovery and development, have led to significant advancements in the labeling of drugs for pediatric use. Facilitated by the emergence of new targets, precision medicine, and innovations in regulatory science, there is now a subtle shift in focus toward drug development research for children rather than simply in children. Although there has been an increase in pediatric studies of investigational agents and labeling of pediatric information for use, there have been unintended consequences of existing policies. As a result, limited progress has been made in certain therapeutic areas and for off-patent therapies. Future policy reform to enhance the availability and accessibility of pediatric medicines should not only reflect an understanding not only of the successes of existing policy and legislative initiatives but also constructively address failures and unintended consequences. Taken together, policy reform, global cooperation, and innovation in regulatory science will more ably deliver better pediatric therapies tomorrow.

Food and Drug Administration's Humanitarian Device Exemption Marketing Approval Pathway: Insights for Developing Devices for Rare Diseases

The Food and Drug Administration's (FDA) Humanitarian Device Exemption (HDE) is a unique marketing approval pathway for medical devices targeting diseases affecting small (rare) patient populations. In an effort to increase the utilization and success of this pathway, the FDA has analyzed data from HDE approvals from 2007 to 2015 to identify factors that have contributed to a successful HDE marketing application. There were 28 HDE approvals during the analysis period and were based on a broad range of data constituting valid scientific evidence. Most had at least one prospectively conducted clinical trial to support safety and probable benefit. An analysis of these HDE approvals demonstrates that the FDA exercises a high degree of flexibility when reviewing HDE applications.

Orphan drug policies and use in pediatric nephrology

Orphan drugs designed to treat rare diseases are often overpriced per patient. Novel treatments are sometimes even more expensive for patients with ultra-rare diseases, in part due to the limited number of patients. Pharmaceutical companies that develop a patented life-saving drug are in a position to charge a very high price, which, at best, may enable these companies to further develop drugs for use in rare disease. However, is there a limit to how much a life-saving drug should cost annually per patient? Government interventions and regulations may opt to withhold a life-saving drug solely due to its high price and cost-effectiveness. Processes related to drug pricing, reimbursement, and thereby availability, vary between countries, thus having implications on patient care. These processes are discussed, with specific focus on three drugs used in pediatric nephrology: agalsidase beta (for Fabry disease), eculizumab (for atypical hemolytic uremic syndrome), and cysteamine bitartrate (for cystinosis). Access to and costs of orphan drugs have most profound implications for patients, but also for their physicians, hospitals, insurance policies, and society at large, particularly from financial and ethical standpoints.

Taxonomy of rare genetic metabolic bone disorders

This article reports a taxonomic classification of rare skeletal diseases based on metabolic phenotypes. It was prepared by The Skeletal Rare Diseases Working Group of the International Osteoporosis Foundation (IOF) and includes 116 OMIM phenotypes with 86 affected genes.

INTRODUCTION

Rare skeletal metabolic diseases comprise a group of diseases commonly associated with severe clinical consequences. In recent years, the description of the clinical phenotypes and radiographic features of several genetic bone disorders was paralleled by the discovery of key molecular pathways involved in the regulation of bone and mineral metabolism. Including this information in the description and classification of rare skeletal diseases may improve the recognition and management of affected patients.

METHODS

IOF recognized this need and formed a Skeletal Rare Diseases Working Group (SRD-WG) of basic and clinical scientists who developed a taxonomy of rare skeletal diseases based on their metabolic pathogenesis.

RESULTS

This taxonomy of rare genetic metabolic bone disorders (RGMBDs) comprises 116 OMIM phenotypes, with 86 affected genes related to bone and mineral homeostasis. The diseases were divided into four major groups, namely, disorders due to altered osteoclast, osteoblast, or osteocyte activity; disorders due to altered bone matrix proteins; disorders due to altered bone microenvironmental regulators; and disorders due to deranged calciotropic hormonal activity.

CONCLUSIONS

This article provides the first comprehensive taxonomy of rare metabolic skeletal diseases based on deranged metabolic activity. This classification will help in the development of common and shared diagnostic and therapeutic pathways for these patients and also in the creation of international registries of rare skeletal diseases, the first step for the development of genetic tests based on next generation sequencing and for performing large intervention trials to assess efficacy of orphan drugs.

Incremental cost per quality-adjusted life year gained? The need for alternative methods to evaluate medical interventions for ultra-rare disorders

Drugs for ultra-rare disorders (URDs) rank prominently among the most expensive medicines on a cost-per-patient basis. Many of them do not meet conventional standards for cost-effectiveness. In light of the high fixed cost of R&D, this challenge is inversely related to the prevalence of URDs. The present paper sets out to explain the rationale underlying a recent expert consensus on these issues, recommending a more rigorous assessment of the clinical effectiveness of URDs, applying established standards of evidence-based medicine. This may include conditional approval and reimbursement policies, which should be combined with a firm expectation of proof of a minimum significant clinical benefit within a reasonable time. In contrast, current health economic evaluation paradigms fail to adequately reflect normative and empirical concerns (i.e., morally defensible 'social preferences') regarding healthcare resource allocation. Hence there is a strong need for alternative economic evaluation models for URDs.

Improving access to novel agents for childhood leukemia

Leukemia is the most common pediatric cancer. Despite great progress in the development of curative therapy, leukemia remains a leading cause of death from disease in childhood, and survivors are at life-long risk of complications of treatment. New agents are needed to further increase cure rates and decrease treatment-associated toxicities. The complex biology and aggressive nature of childhood leukemia, coupled with the relatively small patient population available for study, pose specific challenges to the development of new therapies. In this review, the authors discuss strategies and initiatives designed to improve access to new agents in the treatment of pediatric leukemia.

The influence of the European paediatric regulation on marketing authorisation of orphan drugs for children

Background

Drug development for rare diseases is challenging, especially when these orphan drugs (OD) are intended for children. In 2007 the EU Paediatric Drug Regulation was enacted to improve the development of high quality and ethically researched medicines for children through the establishment of Paediatric Investigation Plans (PIPs). The effect of the EU Paediatric Drug Regulation on the marketing authorisation (MA) of drugs for children with rare diseases was studied.

Methods

Data on all designated orphan drugs, their indication, MA, PIPs and indication group (adult or child) were obtained from the European Medicines Agency (EMA). The outcome and duration of the process from orphan drug designation (ODD) to MA, was compared, per indication, by age group. The effect of the Paediatric Drug Regulation, implemented in 2007, on the application process was assessed with survival analysis.

Results

Eighty-one orphan drugs obtained MA since 2000 and half are authorised for (a subgroup of) children; another 34 are currently undergoing further investigations in children through agreed PIPs. The Paediatric Drug Regulation did not significantly increase the number of ODDs with potential paediatric indications (58% before vs 64% after 2007 of ODDs, p = 0.1) and did not lead to more MAs for ODs with paediatric indications (60% vs 43%, p = 0.22). ODs authorised after 2007 had a longer time to MA than those authorised before 2007 (Hazard ratio (95% CI) 2.80 (1.84-4.28), p < 0.001); potential paediatric use did not influence the time to MA (Hazard ratio (95% CI) 1.14 (0.77-1.70), p = 0.52).

Conclusions

The EU Paediatric Drug Regulation had a minor impact on development and availability of ODs for children, was associated with a longer time to MA, but ensured the further paediatric development of drugs still off-label to children. The impact of the Paediatric Drug Regulation on research quantity and quality in children through PIPs is not yet clear.

Surgical curability of medullary thyroid cancer in multiple endocrine neoplasia 2B: a changing perspective

OBJECTIVE

This investigation aimed at exploring the suitability of nonendocrine manifestations preceding medullary thyroid cancer (MTC) for early diagnosis of multiple endocrine neoplasia type 2B (MEN 2B).

BACKGROUND

MEN 2B patients, running a high risk of metastatic MTC, must be diagnosed early for biochemical cure.

METHODS

Forty-four MEN 2B patients carrying inherited (3 patients) and de novo (41 patients) M918T RET mutations were examined for signs and symptoms prompting MEN 2B.

RESULTS

All 3 patients with inherited mutations were diagnosed before the age of 1 year and cured of their C-cell disease. Among 41 patients with de novo mutations, MEN 2B was diagnosed in 12 patients after recognition of nonendocrine manifestations [intestinal ganglioneuromatosis (6 patients), oral symptoms (5 patients), ocular ("tearless crying") (4 patients), and skeletal stigmata (1 patient) alone or concomitantly]. In the remaining 29 patients with de novo mutations, the diagnosis of MEN 2B was triggered by symptomatic MTC (28 patients) or pheochromocytoma (1 patient). The former patients, being significantly (P < 0.001) younger (means of 5.3 vs 17.6 years) and having lower calcitonin levels (means of 115 vs 25,519 pg/mL), smaller tumors (67% vs 0% were ≤10 mm) and less often extrathyroidal extension (0% vs 81%), lymph node (42% vs 100%), and distant metastases (8% vs 79%), were biochemically cured more often (58% vs 0%).

CONCLUSIONS

MTC is curable in patients with de novo mutations when nonendocrine MEN 2B components are quickly appreciated and surgical intervention is performed before patients turn 4 years old.

Next-generation sequencing applied to rare diseases genomics

Genomics has revolutionized the study of rare diseases. In this review, we overview the latest technological development, rare disease discoveries, implementation obstacles and bioethical challenges. First, we discuss the technology of genome and exome sequencing, including the different next-generation platforms and exome enrichment technologies. Second, we survey the pioneering centers and discoveries for rare diseases, including few of the research institutions that have contributed to the field, as well as an overview survey of different types of rare diseases that have had new discoveries due to next-generation sequencing. Third, we discuss the obstacles and challenges that allow for clinical implementation, including returning of results, informed consent and privacy. Last, we discuss possible outlook as clinical genomics receives wider adoption, as third-generation sequencing is coming onto the horizon, and some needs in informatics and software to further advance the field.

New Financial and Research Models for Pediatric Orphan Drug Development - Focus on the NCATS TRND Program

While there are approximately 7,000 identified human diseases considered as "rare" based on population prevalence or incidence, the cumulative impact runs into the millions of patients globally. Although the genetic underpinnings of more than 2,000 rare diseases have been elucidated, there remains a paucity of therapeutic options, frequently due to lack of commercial interest. Development programs suffer high attrition within the so-called "Valley of Death," in which the risks of scientific failure are still too high to justify the increasing development costs. This problem is common to any drug development campaign, but it is particularly exacerbated in the rare diseases, many of which arise in childhood. To stimulate development of therapeutics for these otherwise underserved patient populations, a number of regulatory incentives and research initiatives have been established. Extended patent protections, expedited regulatory reviews for qualified drug sponsors, and clinical trial grant support aim to foster interest in completing development programs. To stimulate researchers to embark on rare disease drug development campaigns, earlier-stage preclinical research resources have been created, as well, such as the Therapeutics for Rare and Neglected Diseases (TRND) program at the U.S. National Institutes of Health (NIH). TRND is a unique NIH program created to support drug development through formation of public-private partnerships. These partnerships leverage the robust biopharmaceutical industry experience of the TRND staff scientists and the deep disease area expertise of the collaborating partners. Each project adopted into the TRND portfolio aims to satisfy two broad goals: developing a novel therapy for a rare or otherwise neglected disease, and exploring ways to accelerate the drug development process overall so that lessons learned can be disseminated to the wider community undertaking translational research. This article discusses common obstacles and opportunities for therapeutic development, and provides examples of the types of projects TRND has undertaken across a broad range of pediatric rare disorders.

Collaborative development of 2-hydroxypropyl-β-cyclodextrin for the treatment of Niemann-Pick type C1 disease

In 2010, the National Institutes of Health (NIH) established the Therapeutics for Rare and Neglected Diseases (TRND) program within the National Center for Advancing Translational Sciences (NCATS), which was created to stimulate drug discovery and development for rare and neglected tropical diseases through a collaborative model between the NIH, academic scientists, nonprofit organizations, and pharmaceutical and biotechnology companies. This paper describes one of the first TRND programs, the development of 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) for the treatment of Niemann-Pick disease type C1 (NPC1). NPC is a neurodegenerative, autosomal recessive rare disease caused by a mutation in either the NPC1 (about 95% of cases) or the NPC2 gene (about 5% of cases). These mutations affect the intracellular trafficking of cholesterol and other lipids, which leads to a progressive accumulation of unesterified cholesterol and glycosphingolipids in the CNS and visceral organs. Affected individuals typically exhibit ataxia, swallowing problems, seizures, and progressive impairment of motor and intellectual function in early childhood, and usually die in adolescence. There is no disease modifying therapy currently approved for NPC1 in the US. A collaborative drug development program has been established between TRND, public and private partners that has completed the pre-clinical development of HP-β-CD through IND filing for the current Phase I clinical trial that is underway. Here we discuss how this collaborative effort helped to overcome scientific, clinical and financial challenges facing the development of new drug treatments for rare and neglected diseases, and how it will incentivize the commercialization of HP-β-CD for the benefit of the NPC patient community.

Pharmacotherapy challenges of Fontan-associated plastic bronchitis: a rare pediatric disease

Pediatric pharmacotherapy is often challenging due to the paucity of available clinical data on the safety and efficacy of drugs that are commonly used in children. This quandary is even more prevalent in children with rare diseases. Although extrapolations for dosing and administration are often made from available adult data with similar disease states, this translation becomes even more problematic in rare pediatric diseases. Understanding of rare disease pathophysiology is typically poor, and few, if any, effective therapies have been studied and identified. One condition that illustrates these issues is plastic bronchitis, a rare, most often pediatric disease that is characterized by the production of obstructive bronchial airway casts. This illness primarily occurs in children with congenital heart disease, often after palliative surgery. Plastic bronchitis is a highly clinically relevant and therapeutically challenging problem with a high mortality rate, and, a generally accepted effective pharmacotherapy regimen has yet to be identified. Furthermore, the disease is ill defined, which makes timely identification and treatment of children with plastic bronchitis difficult. The pharmacotherapies currently used to manage this disease are largely anecdotal and vary between the use of macrolide antibiotics, mucolytics, bronchodilators, and inhaled fibrinolytics in a myriad of combinations. The purpose of this review is 2-fold: first, to highlight the dilemma of treating plastic bronchitis, and second, to bring attention to the continuing need for studies of drug therapies used in children so safe and effective drug regimens can be established, particularly for rare diseases.

New policies to address the global burden of childhood cancers

Childhood cancer is a major global health issue. Every year, almost 100 000 children die from cancer before the age of 15 years, more than 90% of them in resource-limited countries. Here, we review the key policy issues for the delivery of better care, research, and education of professionals and patients. We present a key list of time-limited proposals focusing on change to health systems and research and development. These include sector and system reforms to make care affordable to all, policies to promote growth of civil society around both cancer and Millennium Development Goals, major improvements to public health services (particularly the introduction of national cancer plans), improved career development, and increased remuneration of specialist health-care workers and government support for childhood cancer registries. Research and development proposals focus on sustainable funding, the establishment of more research networks, and clinical research specifically targeted at the needs of low-income and middle-income countries. Finally, we present proposals to address the need for clinical trial innovation, the complex dichotomy of regulations, and the threats to the availability of data for childhood cancers.

IOM Review of FDA--approved biologics labeled or studied for pediatric use

BACKGROUND

Studies have examined the extent to which public policies such as the Best Pharmaceuticals for Children Act have increased pediatric information in drug labeling. Little attention has focused on pediatric labeling of biologics. This analysis examines the extent to which biologics are labeled for pediatric use or have been studied in children.

METHODS

The analysis covers the 96 biologics (excluding vaccines) that were first licensed by the Food and Drug Administration between 1997 and 2010 and were still marketed as of 2010. Product labeling was consulted for information on approved pediatric uses, pediatric studies, or pediatric safety warnings based on analyses of adverse events. The online database ClinicalTrials.gov was searched for registered pediatric studies of these biologics. A separate analysis examined labeling and studies for 55 vaccines.

RESULTS

For ∼60% of the 96 biologics, labeling shows approved pediatric use or pediatric study information or both. Approximately 85% of the biologics have ≥1 registered pediatric trial completed, underway, or planned. Overall, ∼90% are labeled for pediatric use, have pediatric information in the label, have a registered pediatric study, or have some combination of these characteristics. For the 55 analyzed vaccines, the corresponding figure is 95%.

CONCLUSIONS

A majority of biologics approved in the past 15 years include some pediatric information in their labeling, and pediatric trials have been registered for a substantial majority of these products.

Orphan drugs, orphan diseases. The first decade of orphan drug legislation in the EU

PURPOSE

To assess the methodological quality of Orphan Medicinal Product (OMP) dossiers and discuss possible reasons for the small number of products licensed.

METHODS

Information about orphan drug designation, approval, refusal or withdrawal was obtained from the website of the European Medicines Agency and from the European Public Assessment Reports.

RESULTS

From 2000 up to 2010, 80.9 % of the 845 candidate orphan drug designations received a positive opinion from the European Medicines Agency (EMA)'s Committee on Orphan Medicinal Products. Of the 108 OMP marketing authorizations applied for, 63 were granted. Randomised clinical trials were done for 38 OMPs and placebo was used as comparator for nearly half the licensed drugs. One third of the OMPs were tested in trials involving fewer than 100 patients and more than half in trials with 100-200 cases. The clinical trials lasted less than one year for 42.9 % of the approved OMPs.

CONCLUSION

Although there may have been some small improvements over time in the methods for developing OMPs, in our opinion, the number of patients studied, the use of placebo as control, the type of outcome measure and the follow-up have often been inadequate. The present system should be changed to find better ways of fostering the development of effective and sustainable treatments for patients with orphan diseases. Public funds supporting independent clinical research on OMPs could bridge the gap between designation and approval. More stringent criteria to assess OMPs' efficacy and cost/effectiveness would improve the clinical value and the affordability of products allowed onto the market.

Functional Rescue of F508del-CFTR Using Small Molecule Correctors

High-throughput screens for small molecules that are effective in “correcting” the functional expression of F508del-CFTR have yielded several promising hits. Two such compounds are currently in clinical trial. Despite this success, it is clear that further advances will be required in order to restore 50% or greater of wild-type CFTR function to the airways of patients harboring the F508del-CFTR protein. Progress will be enhanced by our better understanding of the molecular and cellular defects caused by the F508del mutation, present in 90% of CF patients. The goal of this chapter is to review the current understanding of defects caused by F508del in the CFTR protein and in CFTR-mediated interactions important for its biosynthesis, trafficking, channel function, and stability at the cell surface. Finally, we will discuss the gaps in our knowledge regarding the mechanism of action of existing correctors, the unmet need to discover compounds which restore proper CFTR structure and function in CF affected tissues and new strategies for therapy development.

Quantitative analysis to guide orphan drug development

The development of orphan drugs for rare diseases has made impressive strides in the past 10 years. There has been a surge in orphan drug designations, but new drug approvals have not kept up. This article presents a three-pronged hierarchical strategy for quantitative analysis of data at the descriptive, mechanistic, and systems levels of the biological system that could represent a standardized and rational approach to orphan drug development. Examples are provided to illustrate the concept.