Conducting Drug Treatment Trials in Children: Opportunities and Challenges.

Children were often referred to as "therapeutic orphans" in the past due to different reasons such as ethical, regulatory, economic, scientific, etc., ones. They were exposed to avoidable risks while missing out on therapeutic advances. Pediatric patients have suffered from a lack of scientific and regulatory standards (e.g., proper drug testing, authorization of medicines for their use, etc.), although the pharmaceutical legislative framework, which ensures the high standards of safety, quality, and efficacy of medicinal products for use in adults, was developed primarily in response to past "drug disasters," mainly involving children. The adoption of pediatric regulatory initiatives first in the USA and then in Europe and other countries and regions has significantly changed the worldwide frameworks and permanently changed pediatric drug research and development. This article tries to give various perspectives with historical context, a review of the different challenges and opportunities as well as important stakeholders in pediatric drug development. The pediatric trial networks are probably the most important stakeholder that enables efficient patient recruitment, access to better resource utilization, and global collaboration of different stakeholders necessary for performing quality and well-designed clinical trials.

A novel MCGDM technique based on correlation coefficients under probabilistic hesitant fuzzy environment and its application in clinical comprehensive evaluation of orphan drugs.

Probabilistic hesitant fuzzy sets (PHFSs) are superior to hesitant fuzzy sets (HFSs) in avoiding the problem of preference information loss among decision makers (DMs). Owing to this benefit, PHFSs have been extensively investigated. In probabilistic hesitant fuzzy environments, the correlation coefficients have become a focal point of research. As research progresses, we discovered that there are still a few unresolved issues concerning the correlation coefficients of PHFSs. To overcome the limitations of existing correlation coefficients for PHFSs, we propose new correlation coefficients in this study. In addition, we present a multi-criteria group decision-making (MCGDM) method under unknown weights based on the newly proposed correlation coefficients. In addition, considering the limitations of DMs' propensity to use language variables for expression in the evaluation process, we propose a method for transforming the evaluation information of the DMs' linguistic variables into probabilistic hesitant fuzzy information in the newly proposed MCGDM method. To demonstrate the applicability of the proposed correlation coefficients and MCGDM method, we applied them to a comprehensive clinical evaluation of orphan drugs. Finally, the reliability, feasibility and efficacy of the newly proposed correlation coefficients and MCGDM method were validated.

[Translated article] Current situation and evolution of the availability of drugs in the pediatric population in Spain.

OBJECTIVE: To analyze the characteristics of the new medicines approved in the pediatric population in the last 3 years, both those with studies only in the pediatric population and those that extend their indication in this population group, as well as the current situation in relation to their marketing and financing. METHODS: Descriptive observational study of all drugs that include an indication in the pediatric population in Spain (by extension of the indications of drugs already authorized or because they are new drugs that already include an indication in this population group), from January 2019 to March 2022. RESULTS: During the study period, 129 drugs included their indication in the pediatric population. 13.9% of them are not marketed, 46.5% are in a situation of non-financing, under study or without a request for financing, and 4.6% are financed for a specific pediatric subpopulation. 52.7% are original drugs, 4.7% are generic, 38.8% are biological, 3.8% are biosimilar, and 17.8% are orphan drugs. 57.36% of these medicines obtain the pediatric indication due to extension of the indication and 42.64% obtain it because they are new medicines that already include their studies in the pediatric population. CONCLUSIONS: Drugs with authorized indications are increasingly available in the pediatric population and the trend is to extend the indication of authorized drugs to the adult population. However, barriers in terms of financing and marketing need to be expedite and overcome to facilitate access to them.

Trends from two decades of orphan designations in paediatric rare neuromuscular diseases.

Rare diseases are characterized by substantial unmet need mostly because the majority have limited, or no treatment options and a large number also affect children. Since the inception of EU orphan regulation in 2000 the European Medicines Agency Committee for Orphan Medicinal Products has received several applications for paediatric rare neuromuscular diseases (PERAN) however treatment options remain limited. Here we discuss the results form an observational, retrospective, cross-sectional study to characterize the currently authorised orphan medicinal products (OMP) and orphan designations (OD) given to products for PERAN in the last two decades. In the EU about half of PERAN diseases have at least one active OD approved since 2000, and about half of these are for Duchenne muscular dystrophy (DMD). The large majority of PERAN diseases do not have an authorised medicine with only 6 OMP currently authorised for Spinal muscular atrophy (3); DMD (1) and Myasthenia gravis (2). One in five products have inactive or discontinued regulatory development but clinical trials are ongoing for the vast majority of PERAN diseases, and more than half are in the final stage of clinical research with significantly more products with medical plausibility based in clinical data reaching advanced stages in clinical development.

Successes and pitfalls in orphan drug development for sickle cell disease.

ABSTRACT: Sickle cell disease (SCD) is a hereditary red cell disorder with a large disease burden at a global level. In the United States and Europe, medicines may qualify for orphan designation (OD), a regulatory status that provides incentives to boost development. We evaluated the development of new therapies for SCD using data for OD granted in the United States and Europe over the last 2 decades (2000-2021). We analyzed their characteristics, pathophysiological targets, trends, and OD sponsors. We then investigated the approval outcomes, including the phase success rate and reasons for discontinuation across different variables. We identified 57 ODs for SCD: 43 (75.4%) small molecules, 32 (56.1%) for oral administration, and 36 (63.1%) for chronic use to prevent SCD complications. At the end of the study (2021), development of 34 of 57 ODs was completed. Four ODs were approved with a success rate of 11.8%. Products targeting upstream causative events of SCD pathophysiology had a 1.8 higher success rate compared with products targeting disease consequences. Large companies showed a fourfold higher success rate compared with small-medium enterprises. Failures in clinical development were mainly seen in phase 3 for a lack of efficacy on vaso-occlusive crisis as the primary study end point, likely related to variable definitions and heterogeneity of pain scoring and treatment. Both advances in SCD knowledge and regulatory incentives paved the way for new therapies for SCD. Our finding of high failure rates in late-stage clinical development signals the need for better early-stage predictive models, also in the context of meaningful clinical end points.

2023 in review: FDA approvals of new medicines.

An analysis of all new entities approved by both the Center for Drug Evaluation and Research (CDER) and the Center for Biologics Evaluation and Research (CBER) identified the approval of 69 new entities in the year 2023, 50 % more than in the previous year. Oncology drugs tied with congenital and infectious diseases drugs for the most approvals. Although orphan and priority approvals continued at a high pace, the rate of fast-track approvals continued to decline. The rate of industry consolidation also picked up again after decreasing slightly in 2022.

A systematic review of real-world evidence (RWE) supportive of new drug and biologic license application approvals in rare diseases.

BACKGROUND: Real-world evidence (RWE) generated using real-world data (RWD) presents the potential to contextualize and/or supplement traditional clinical trials for regulatory approval of rare diseases (RDs). This systematic review evaluated the use of RWD for non-oncologic RD therapies with orphan drug designation (ODD) to support efficacy outcomes in regulatory application packages to the US Food and Drug Administration (FDA). New drug applications (NDAs) and biologic license applications (BLAs) submitted between January 2017 and October 2022 were obtained from publicly available FDA drug approval websites. NDAs and BLAs of non-oncologic RD therapies were screened, and manually reviewed using RWE-related keywords. Quantitative summary of number/proportion of study types was provided, whereas qualitative synthesis focused on key categories of output assessing the use of RWD in overall drug approval process, including agency's feedback on its strengths and key challenges. RESULTS: A total of 868 NDAs and BLAs were identified, of which 243 were screened for non-oncologic RDs with ODD, and 151 were subsequently reviewed for the RWD used to support efficacy outcomes. Twenty (12 NDAs, 8 BLAs) applications met the review inclusion criteria. Most (19; 95%) applications used only retrospective RWD, while one (5%) collected RWD both retrospectively and prospectively. RWD studies included natural history including registry-based/retrospective historical controls (14; 70%), retrospective medical chart-reviews (4; 20%), and external RWD controls from other studies (2; 10%). The FDA generally accepted RWD studies demonstrating a large effect size despite the noted concerns and criticisms. However, the agency expressed concerns about overall quality and comparability of RWD with trial data for some applications, including RWD study designs with respect to differences in patients' baseline characteristics, missing information, and potential bias and measurement errors. CONCLUSIONS: This systematic review highlights potential benefits of appropriately conducted RWE studies in RD, which can strengthen the clinical evidence for efficacy comparison and contextualization to support product approval efforts, particularly when a large magnitude of effect is observed for the new intervention. Nonetheless, quality and completeness of RWD and its comparability with trial data remain areas of concern that can serve as valuable learnings for advancing future science and regulatory approvals.

Prescription Drug Prices: An AAN Position Statement.

This position statement serves to establish the AAN's stance on the methods to address the cost of prescription drugs being considered by state and federal policymakers so that the AAN can continue to advocate effectively for its members. Neurologists seek to provide high-value care for patients with neurologic diseases at the lowest cost possible. However, many therapies for neurologic diseases are among the most expensive in the United States. The 3 major cost challenges include (1) unjustified increases in the pricing for drugs used to treat neurologic disorders, (2) the high cost of medications used to treat rare diseases where there are limited or no therapeutic options available, and (3) the high cost of noninnovative (already FDA-approved) therapies that used accelerated FDA approval pathways or Orphan Drug Act designated to expedite approvals in neurologic disorders. In each of these cases, AAN is concerned that the high cost does not deliver sufficient value to patients or society. The AAN's position is that action must be taken to ensure that effective prescription medications are accessible for patients with complex, chronic neurologic conditions. Potential solutions should be affordable, simple, and transparent. Cost-containment efforts must also address the burden on the entire healthcare system because high prescription drug prices may be shifted and absorbed in ways that negatively affect patient and prescriber access to important medications. AAN supports price negotiations, the cost saving potential of generics and biosimilars, development of novel therapeutics, price transparency, and importation.

Analysis of US Food and Drug Administration new drug and biologic approvals, regulatory pathways, and review times, 1980-2022.

U.S. laws enacted since 1983 have aimed to enhance the development and marketing of new pharmaceutical products. We thoroughly characterized all new molecular entities, therapeutic biologics, and gene and cell therapies approved by the US Food and Drug Administration (FDA) during the period 1980-2022 in the context of these laws and regulations. Throughout the study period, the FDA approved 1355 new pharmaceutical products. The median FDA review time decreased from 26.6 months prior to the Prescription Drug User Fee Act (1992), which authorized the FDA to collect fees from drug companies to 9.9 months after the Food and Drug Administration Safety and Innovation Act (2012), which created new designations that eliminated the requirement for evidence of added therapeutic benefit for FDA expedited drug review. The greatest increase in approvals occurred in antineoplastic and immunomodulating drugs, biologics, and orphan drugs. More than half of new drug approvals benefited from regulatory designations and pathways that did not require addressing unmet medical needs or demonstrating therapeutic benefit over available alternatives. The legislative goal of bringing more drugs to the market faster has been achieved. Further studies are needed to determine the therapeutic value to patients of new drugs approved using expedited approval pathways.

A Step Toward the Development of the First National Multi-Criteria Decision Analysis Framework to Support Healthcare Decision Making in Saudi Arabia.

OBJECTIVES: To assess the feasibility of implementing multi-criteria decision analysis (MCDA) and to select the criteria for preparing a national MCDA framework for health technology assessment of orphan drugs in the Kingdom of Saudi Arabia (KSA). METHODS: The study was conducted in 3 phases. In phase I, a targeted literature review was performed to gather relevant information on the implementation of MCDA in healthcare decision making. Phase II was a cross-sectional survey, conducted to obtain insights from different stakeholders and key opinion leaders on specific topics from the KSA perspective. Phase III included a round-table discussion involving experts to validate the results obtained in the phase II survey and further elaborate on specific requirements that may be critical for developing the first national MCDA framework in the KSA. RESULTS: All the key opinion leaders involved in the study acknowledged the importance of implementing MCDA in the KSA. The Ministry of Health was assigned the responsibility of chairing the MCDA decision process. The experts selected the quantitative, qualitative, and economic criteria to be considered for the MCDA framework. The stakeholders decided to initiate a pilot phase using the deliberative MCDA methodology for the assessment of orphan drugs based on the selected criteria for a period of 1 year and then reevaluate the need to adapt the pragmatic MCDA model. CONCLUSION: This article describes the novel initiative that examined the feasibility and process required for the development of the first MCDA framework in the KSA to support healthcare decision making.

Orphan drug development: Challenges, regulation, and success stories.

Rare diseases, also known as orphan diseases, are diseases with low occurrence in the population. Developing orphan drugs is challenging because of inadequate financial and scientific resources and insufficient subjects to run clinical trials. With advances in genome sequencing technologies, emergence of cell and gene therapies, and the latest developments in regulatory pathways, some orphan drugs that have curative potential have been approved. In India, due to its large population and resource crunch, developing orphan drugs is phenomenally challenging. After adopting the Orphan Drug Act, the US-FDA has continuously made advances in regulatory pathways for orphan drugs. Particularly, n-of-one clinical trials have been successful in some cases. India has recently adopted policies that have impacted the long-neglected rare-disease ecosystem; however, there is no clear regulatory path for orphan drug development in India. We have proposed a multi-pronged approach involving close collaboration between the government, regulatory bodies, industries, and patient advocacy groups to boost orphan drug development in India. We believe that rapidly evolving technologies and business models can enable better and faster development of novel orphan drugs in India and other resource-constrained countries.

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.

Trends in orphan medicinal products approvals in the European Union between 2010-2022.

BACKGROUND: Over the last twenty years of orphan drug regulation in Europe, the regulatory framework has increased its complexity, with different regulatory paths and tools engineered to facilitate the innovation and accelerate approvals. Recently, the proposal of the new Pharmaceutical Legislation for the European Union, which will replace at least three Regulations and one Directive, was released and its new framework is raising many questions. The aim of this study was to present a characterisation of the Orphan Medicinal Products (OMPs) authorised by the European Commission (EC), between 2010 and 2022, looking into eighteen variables, contributing to the ongoing discussion on the proposal and implementation of the new Pharmaceutical Legislation proposed. METHODS: Data of the OMPs identified and approved between 2010 and 2022 were extracted from the European Public Assessment Reports (EPARs) produced by the European Medicines Agency. Information regarding legal basis of the application, applicant, protocol assistance received, type of authorization, registration status, type of molecule, ATC code, therapeutic area, target age, disease prevalence, number of pivotal clinical trials supporting the application, clinical trial designs, respective efficacy endpoints and number of patients enrolled in the pivotal clinical trials were extracted. A descriptive statistical analysis was applied. RESULTS: We identified 192 OMPs approved in the period between 2010 and 2022. 89% of the OMPs have legal basis of "full application". 86% of the sponsors received protocol assistance whereas 64% of the MAA benefited from the accelerated assessment. 53% of the active substances are small molecules; about 1 in 5 molecules are repurposed. 40% of the OMPs have oncological therapeutic indications and 56% of the OMPs are intended to treat only adults. 71% of the products were approved based on a single pivotal trial. CONCLUSIONS: This analysis of OMPs approved between 2010 and 2022 shows that a shift has occurred in the rare disease medicine development space. Through the period studied we observe an increase of non-small molecules approved, accelerated assessment received and non-standard MA's granted.

Analysis and comparative evaluation of expedited programs for gene therapy products: insights from the United States, the European Union, Japan, and South Korea.

Gene therapy products (GTPs) used for incurable diseases can be expedited for early commercialization to fulfill unmet needs. This study analyzed the expedited programs available for GTPs in the US, EU, Japan, and South Korea using their regulatory authorities' websites, related regulations, and documents. In total, there were five expedited programs available for GTPs in the US, four in the EU, and three in both Japan and South Korea, of which four are tailored for GTPs. These programs, sharing similar objectives, can be categorized as those expediting drug development, review, and approval. However, variations are observed in eligibility criteria, specific benefits, and post-marketing study conditions across regulatory authorities. Additionally, the criteria for orphan drug designation for a rare disease differs in prevalence thresholds, incentive offered, and marketing exclusivity period. Overall, 19 GTPs were approved-13 in the US, 14 in the EU, eight in Japan, and three in South Korea-with majority obtaining regulatory approval through at least one expedited program. Therefore, future studies can analyze whether acquiring multiple expedited programs accelerates the drug development and commercialization of GTPs compared with when only one expedited program is processed. Additionally, inter-authority scientific discussion is encouraged for harmonization of expedited program requirements.

Orphan Drug Label Expansions: Analysis Of Subsequent Rare And Common Indication Approvals.

The Orphan Drug Act of 1983 was enacted to provide financial incentives to stimulate drug development for rare diseases. In recent years, concerns have been raised regarding these orphan drugs, including how many are being approved for both rare and common diseases and the number of subsequent indication approvals. Policy makers have suggested modifications to the Orphan Drug Act's incentives to address these concerns. In this study we investigated the approval "family trees" of orphan drugs. We found that 491 novel orphan drugs were approved between 1990 and 2022. To date, 65 percent have been approved for a single rare disease, 15 percent have been approved for multiple rare diseases, and 20 percent have been approved for both rare and common diseases. Ten percent of orphan drugs received a subsequent indication approval for a pediatric population of an orphan disease. Revenue estimates from 2021 show that one-third of the drugs approved for both rare and common indications and 6 percent of rare-only drugs were among the 200 top-selling drugs worldwide. The results have implications for the possible externalities of modifying the incentives of the Orphan Drug Act, such as a potential decrease in the initiation of programs to develop pediatric rare disease drugs.

Implementation status of pharmacological studies in the development of orphan drugs.

BACKGROUND: The nonclinical as well as clinical development of orphan drugs is difficult, owing to unknown pathophysiology and the absence of animal models. Both, the U.S. Food and Drug Administration (FDA) Guidance and European Medicines Agency (EMA) Guidelines, for orphan drug development describe non-clinical studies, but lack specific information, such as animal species and study design. Against this background, this study aimed to elucidate efficient methods for evaluating nonclinical efficacy based on a review report of orphan drugs approved in Japan. RESULTS: A total of 184 orphan drugs, including 84 anticancer and 100 non-anticancer drugs, approved in Japan from January 2010 to December 2019 were investigated. Some anticancer drugs progressed to clinical development without distinct efficacy data in nonclinical studies. Patient-derived cells have been used for some drugs due to a lack of established cell lines. Cells used for non-clinical studies were devised for drugs indicated for cancers resistant to prior therapies, tumours with specific amino acid mutations in the target molecules, and solid tumours with specific biomarkers. For some non-anticancer drugs, similar disease animal models and normal animals were used for evaluation, since animal models did not exist. Biomarkers have been used specifically for evaluation in normal animals and as endpoints in some clinical trials. CONCLUSIONS: It was possible to evaluate drug efficacy by flexibly designing nonclinical studies according to disease characteristics for potentials orphan drugs. These approaches, which are not described in detail in the EMA Guideline or FDA Guidance, may thus lead to approval.

Applying the win ratio method in clinical trials of orphan drugs: an analysis of data from the COMET trial of avalglucosidase alfa in patients with late-onset Pompe disease.

BACKGROUND: Clinical trials for rare diseases often include multiple endpoints that capture the effects of treatment on different disease domains. In many rare diseases, the primary endpoint is not standardized across trials. The win ratio approach was designed to analyze multiple endpoints of interest in clinical trials and has mostly been applied in cardiovascular trials. Here, we applied the win ratio approach to data from COMET, a phase 3 trial in late-onset Pompe disease, to illustrate how this approach can be used to analyze multiple endpoints in the orphan drug context. METHODS: All possible participant pairings from both arms of COMET were compared sequentially on changes at week 49 in upright forced vital capacity (FVC) % predicted and six-minute walk test (6MWT). Each participant's response for the two endpoints was first classified as a meaningful improvement, no meaningful change, or a meaningful decline using thresholds based on published minimal clinically important differences (FVC ± 4% predicted, 6MWT ± 39 m). Each comparison assessed whether the outcome with avalglucosidase alfa (AVA) was better than (win), worse than (loss), or equivalent to (tie) the outcome with alglucosidase alfa (ALG). If tied on FVC, 6MWT was compared. In this approach, the treatment effect is the ratio of wins to losses ("win ratio"), with ties excluded. RESULTS: In the 2499 possible pairings (51 receiving AVA × 49 receiving ALG), the win ratio was 2.37 (95% confidence interval [CI], 1.30-4.29, p = 0.005) when FVC was compared before 6MWT. When the order was reversed, the win ratio was 2.02 (95% CI, 1.13-3.62, p = 0.018). CONCLUSION: The win ratio approach can be used in clinical trials of rare diseases to provide meaningful insight on treatment benefits from multiple endpoints and across disease domains.

Uptake of orphan drugs in the WHO essential medicines lists.

Objective: We evaluated the uptake of medicines licensed as orphan drugs by the United States Food and Drug Administration (FDA) or European Medicines Agency (EMA) into the WHO Model list of essential medicines and the WHO Model list of essential medicines for children from 1977 to 2021. Methods: We collated and analysed data on drug characteristics, reasons for adding or rejecting medicines, and time between regulatory approval and inclusion in the lists. We compared trends in listing orphan drugs before and after revisions to the inclusion criteria of the essential medicines lists in 2001, as well as differences in trends for listing orphan and non-orphan drugs, respectively. Findings: The proportion of orphan drugs in the essential medicines lists increased from 1.9% (4/208) in 1977 to 14.6% (70/478) in 2021. While orphan drugs for communicable diseases have remained stable over time, we observed a considerable shift towards more orphan drugs for noncommunicable diseases, particularly for cancer. The median period for inclusion in the essential medicines lists after either FDA or EMA first approval was 13.5 years (range: 1-28 years). Limited clinical evidence base and uncertainty about the magnitude of net benefit were the most frequent reasons to reject proposals to add new orphan drugs to the essential medicines lists. Conclusion: Despite lack of a global definition of rare diseases, the essential medicines lists have broadened their scope to include medicines for rare conditions. However, the high costs of many listed orphan drugs pose accessibility and reimbursement challenges in resource-constrained settings.