Clinical trial safety population size: analysis of drug approvals for rare and common indications by FDA Center for Drug Evaluation and Research

Achieving big with small: quantitative clinical pharmacology tools for drug development in pediatric rare diseases

Pediatric populations represent a major fraction of rare diseases and compound the intrinsic challenges of pediatric drug development and drug development for rare diseases. The intertwined complexities of pediatric and rare disease populations impose unique challenges to clinical pharmacologists and require integration of novel clinical pharmacology and quantitative tools to overcome multiple hurdles during the discovery and development of new therapies. Drug development strategies for pediatric rare diseases continue to evolve to meet the inherent challenges and produce new medicines. Advances in quantitative clinical pharmacology research have been a key component in advancing pediatric rare disease research to accelerate drug development and inform regulatory decisions. This article will discuss the evolution of the regulatory landscape in pediatric rare diseases, the challenges encountered during the design of rare disease drug development programs and will highlight the use of innovative tools and potential solutions for future development programs.

The Impact of Variability in Patient Exposure During Premarket Clinical Development on Postmarket Safety Outcomes

We characterized the size of the premarket safety population for 278 small-molecule new molecular entities (NMEs) and 61 new therapeutic biologics (NTBs) approved by the US Food and Drug Administration (FDA) between October 1, 2002, and December 31, 2014, evaluating the relationship of premarket safety population size to regulatory characteristics and postmarket safety outcomes. The median size of the safety population was 1,044, and was lower for NTBs than NMEs (median: 920 vs. 1,138, P = 0.04), orphan products than nonorphan products (393 vs. 1,606, P < 0.001), and for products with fast-track designation (617 vs. 1,455, P < 0.001), priority review (630 vs. 1,735, P < 0.001), and accelerated approval (475 vs. 1,164, P < 0.001), than products without that designation. The median number of postmarket safety label updates and issues added to the label were higher with larger premarket exposure among nonorphan products, but not among orphan products. Products with accelerated approval using a surrogate end point had a higher median number of safety issues added to the label than those with full approval, but this did not vary with the size of the safety population; fast-track and priority review were not associated with the number of safety issues added to the label. A smaller safety population size was associated with a longer time to first safety outcome for nonorphan products but not orphan products. For orphan and nonorphan products combined, smaller premarket safety population size is not associated with the number or timing of postmarket safety outcomes, regardless of expedited program participation.

Design and Endpoints for Clinical Trials in Primary Sclerosing Cholangitis

Primary sclerosing cholangitis (PSC) is a rare and chronic liver disease for which there is no effective therapy. Interest has grown in developing treatments for this condition, with several agents proposed as potential therapies. However, there is a lack of clarity about how to measure clinical benefit in trials involving patients with this complex and rare disease. This article reviews regulatory information, the available literature on natural history, as well as potential candidate clinical and surrogate endpoints for PSC. (Hepatology 2018; 00:000-000).

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.

The growing number of hemophilia registries: Quantity vs. quality

Registries for rare diseases provide a tool for obtaining an overview of the clinical situation and can be used to discover points of improvement and to monitor long-term safety. Registries could also become a powerful tool to provide supporting information for marketing authorization. There is an urgent need for a pan-European or global strategy that supports consistent data. Therefore, transparency in data collection, harmonization of the database structures, and the convergence of scientific approaches are required.