Impact Of The Priority Review Voucher Program On Drug Development For Rare Pediatric Diseases

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.

European priority review vouchers for neglected disease product development

INTRODUCTION

Neglected diseases are a significant global health challenge. Encouraging the development of therapeutics and vaccines for these diseases would address an important unmet medical need. We propose a priority review voucher programme for the European Union (EU). The developer of a drug or vaccine for a neglected disease would receive a voucher for accelerated assessment of a different product at the European Medicines Agency (EMA).

METHODS

This study uses retrospective observational data to estimate the potential commercial value of the proposed voucher programme using a five-step approach: (1) estimating the time saved in the EMA accelerated regulatory review; (2) gauging time reductions in accelerated pricing and reimbursement decisions by EU member states; (3) selecting 10 high-revenue products launched between 2015 and 2020 representing typical voucher users; (4) analysing IQVIA MIDAS sales data for the selected products and (5) calculating the net present value (NPV) of the voucher based on the 10 products.

RESULTS

The accelerated EMA review would reduce regulatory time by an average of 182 days. Additionally, products could save more than a year in many member states through an expedited 120-day pricing and reimbursement review. The estimated NPV of regulatory acceleration by two quarters would be €100 million. In addition, if France, Italy and Spain reviewed pricing and reimbursement in only 120 days, then the value would double.

CONCLUSION

An EU voucher estimated at more than €100 million, coupled with a US$100 million counterpart, offers a meaningful incentive for novel product development. However, the voucher programme should be part of a comprehensive strategy for tackling neglected diseases, rather than a standalone solution.

Timing for First-in-Minor Clinical Trials of New Cancer Drugs

OBJECTIVES

To describe the delay for first-in-minor cancer clinical trials and its relationship with the Food and Drug Administration (FDA) approval.

STUDY DESIGN

We used ClinicalTrials.gov to create a sample of pediatric-relevant cancer drugs starting efficacy testing in adults from 2006 through 2011. We characterized the delay between first-in-adult efficacy trials and first-in-minor trials. We also assessed the proportion of drugs evaluated in minors that failed to gain approval, the proportions that were not evaluated in minors before receiving the FDA approval, and whether shorter delay was associated with larger effect sizes or greater probability of regulatory approval.

RESULTS

Thirty-four percent of the 185 drugs in our cohort were evaluated in minors; the median delay to clinical trials was 4.16 years. Of all drugs, 17% received the FDA approval, 41% of which were never tested in minors before licensing. Of the 153 drugs not attaining approval, 78% were not evaluated in minors. Earlier testing did not significantly predict greater response rates (P = .13). Drugs not attaining regulatory approval were evaluated significantly earlier (3.0 for drugs not approved vs 5.4 years delayed testing for approved drugs, P = .019).

CONCLUSIONS

New cancer drugs were typically evaluated in minors years after adult efficacy evaluation. This delay likely eliminated some drugs lacking desirable pharmacology before pediatric testing. However, some drugs that were eliminated may have had activity in pediatric indications. Approaches for prioritizing drugs for pediatric testing warrants further consideration.

Clinical development of new drugs for adults and children with cancer, 2010-2020

BACKGROUND

Many new molecular entities enter clinical development to evaluate potential therapeutic benefits for oncology patients. We characterized adult and pediatric development of the set of new molecular entities that started clinical testing in 2010-2015 worldwide.

METHODS

We extracted data from AdisInsight, an extensive database of global pharmaceutical development, and the FDA.gov website. We followed the cohort of new molecular entities initiating first-in-human phase I clinical trials in 2010-2015 to the end of 2020. For each new molecular entity, we determined whether it was granted US Food and Drug Administration (FDA) approval, studied in a trial open to pediatric enrollment, or stalled during development. We characterized the cumulative incidence of these endpoints using statistical methods for censored data.

RESULTS

The 572 new molecular entities starting first-in-human studies in 2010-2015 were studied in 6142 trials by the end of 2020. Most new molecular entities were small molecules (n = 316, 55.2%), antibodies (n = 148, 25.9%), or antibody-drug conjugates (n = 44, 7.7%). After a mean follow-up of 8.0 years, 173 new molecular entities did not advance beyond first-in-human trials, and 39 were approved by the FDA. New molecular entities had a 10.4% estimated probability (95% confidence interval = 6.6% to 14.1%) of being approved by the FDA within 10 years of first-in-human trials. After a median of 4.6 years since start of first-in-human trials, 67 (11.7%) new molecular entities were tested in trials open to pediatric patients, and 5 (0.9%) were approved for pediatric indications.

CONCLUSIONS

More efficient clinical development strategies are needed to evaluate new cancer therapies, especially for children, and incorporate approaches to ensure knowledge gain from investigational products that stall in development.

Changing incentives to ACCELERATE drug development for paediatric cancer

BACKGROUND

More effective incentives are needed to motivate paediatric oncology drug development, uncoupling it from dependency on adult drug development. Although the current European and North-American legislations aim to promote drug development for paediatrics and rare diseases, children and adolescents with cancer have not benefited as expected from these initiatives and cancer remains the first cause of death by disease in children older than one. Drug development for childhood cancer remains dependent on adult cancer indications and their potential market. The balance between the investment needed to execute a Paediatric Investigation Plan (PIP) in Europe and an initial Paediatric Study Plan (iPSP) in the US, coupled with the potential financial reward has not been sufficiently attractive to incite the pharmaceutical industry to develop drugs for rare indications such as childhood cancer.

METHODS

We propose changes in the timing and nature of the rewards within the European Paediatric Medicine Regulation (PMR) and Regulation on Orphan Medicinal Products (both currently under review), which would drive earlier initiation of paediatric oncology studies and provide incentives for drug development specifically for childhood indications.

RESULTS

We suggest modifying the PMR to ensure mechanism-of-action driven mandatory PIP and reorganization of incentives to a stepwise and incremental approach. Interim and final deliverables should be defined within a PIP or iPSP, each attracting a reward on completion. A crucial change would be the introduction of the interim deliverable requiring production of paediatric data that inform the go/no-go decisions on whether to take a drug forward to paediatric efficacy trials.

CONCLUSION

Additionally, to address the critical gap in the current framework where there is a complete lack of incentives to promote paediatric-specific cancer drug development, we propose the introduction of early rewards in the Orphan Regulation, with a variant on the US-Creating Hope Act and its priority review vouchers.

How Compounding Pharmacies Fill Critical Gaps in Pediatric Drug Development Processes: Suggested Regulatory Changes to Meet Future Challenges

Drugs administered to children in the United States fall into two broad categories: (1) those that have followed the US Food and Drug Administration (US-FDA) pediatric drug approval process and are marketed as finished dosage forms with pediatric labeling; and (2) all others, many of which are used "off-label". The use of most drug products in pediatrics is still off label, often requiring special preparation, packaging, and, in some cases, compounding into preparations. The latter category includes compounded preparations that incorporate either a US-FDA approved finished dosage form (e.g., a sterile solution, sterile powder, nonsterile capsules, oral solution, crushed tablets, etc.), or rely on bulk active pharmaceutical ingredients (APIs). Compounded preparations are prepared for individual patients in 503A pharmacies, or on a larger scale and not just for specific patients, in licensed 503B establishments. Critical gaps in the current drug approval process for finished dosage forms have created a proverbial "Gordian knot" that needs to be untangled thoughtfully to facilitate increased production and approval of vitally needed medications for pediatric patients. This opinion will describe current regulatory processes pertaining to pediatrics-only drug approval in the United States. Additionally, discussed are steps required for a product to acquire pediatric labeling. Gaps in regulatory approval pathways for both manufactured and compounded pediatric drugs will be identified, especially those that complicate and slow development and availability to patients. Finally, suggestions for regulatory modifications that may enhance pediatric product development strategies for both manufacturers and compounders are suggested.

The Impact of the Priority Review Voucher on Research and Development for Tropical Diseases

BACKGROUND

In 2007, the priority review voucher (PRV) was implemented in the US to incentivize research and development (R&D) for tropical diseases. The PRV is issued by the US FDA and grants a quicker review to manufacturers upon successful development of a product for a disease eligible for the program.

OBJECTIVE

The objective of this analysis was to assess whether the PRV has incentivized R&D (measured as clinical trial activity) for the intended tropical diseases.

METHOD

We used a difference-in-difference-in-differences (DDD) strategy by exploiting variation in its implementation across diseases and registries around the world. Clinical trials were retrieved from the World Health Organization International Clinical Trials Registry Platform for the years 2005-2019.

RESULTS

We found a positive, but not statistically significant, effect of the PRV on stimulating R&D activity. Delayed effects of the policy could not be found.

CONCLUSION

Our findings, which were robust across a series of robustness tests, suggest that the PRV program is not associated with a trigger in innovation for neglected diseases and therefore should not be considered as a stand-alone solution. It should be supplemented with other government measures to incentivize R&D activity. To increase the value of the program, we recommend that the PRV only be awarded to novel products and not to products that have already been licensed outside the US. Doing so would restrict the number of vouchers awarded and slow down their ongoing market depreciation. Finally, we propose that product sponsors be required to submit an access plan for PRV-awarded products.

​US Tropical Disease Priority Review Vouchers: Lessons In Promoting Drug Development And Access

The COVID-19 global pandemic has devastated lives and economies. It has served as a reminder of how critical it is to invest in preventing and treating infectious diseases. Until the COVID-19 pandemic, the largest US government-sponsored reward for infectious disease drug and vaccine development was the Tropical Disease Priority Review Voucher program. Under this program, the Food and Drug Administration awards a priority review voucher to the sponsor of a new drug or vaccine for tropical infectious diseases. The voucher then can be exchanged for the faster review of one drug. We provide case studies for tropical disease voucher recipients between 2007 and 2018, examine the effects of the voucher program on product innovation and access, and recommend that policy makers protect the voucher program while creating complementary incentives.

Publication Trends of Pediatric and Adult Randomized Controlled Trials in General Medical Journals, 2005-2018: A Citation Analysis

Policy has been developed to promote the conduct of high-quality pediatric randomized controlled trials (RCTs). Whether these strategies have influenced publication trends in high-impact journals is unknown. We aim to evaluate characteristics, citation patterns, and publication trends of pediatric RCTs published in general medical journals (GMJs) compared with adult RCTs over a 13-year period. Studies were identified using Medline, and impact metrics were collected from Web of Science and Scopus. All RCTs published from 2005–2018 in 7 GMJs with the highest impact factors were identified for analysis. A random sample of matched pediatric and adult RCTs were assessed for publication characteristics, academic and non-academic citation. Citations were counted from publication until June 2019. Among 4146 RCTs, 2794 (67.3%) enrolled adults, 591 (14.2%) enrolled children, and 761 RCTs (18.3%) enrolled adult and pediatric patients. Adult RCTs published in GMJs grew by 5.1 publications per year (95% CI: 3.3–6.9), while the number of pediatric RCTs did not show significant change (−0.4 RCTs/year, 95% CI: −1.4–0.6). Adult RCTs were cited more than pediatric RCTs (median(IQR): 29.9 (68.5–462.8) citations/year vs. 13.2 (6.8–24.9) citations/year; p < 0.001); however, social media attention was similar (median(IQR) Altmetric Attention Score: 37 (13.75–133.8) vs. 26 (6.2–107.5); p = 0.25). Despite policies which may facilitate conduct of pediatric RCTs, the publishing gap in high-impact GMJs is widening.

Pediatric Trials for Cancer Therapies With Targets Potentially Relevant to Pediatric Cancers

The Research to Accelerate Cures and Equity (RACE) for Children Act was enacted in 2017 to authorize the US Food and Drug Administration (FDA) to require pediatric studies for new cancer drugs that have a molecular target relevant to the growth or progression of a pediatric cancer. To assess the possible scope of this new policy, we examined all 78 adult cancer drugs approved by the FDA from 2007 to 2017. Only 17 (21.8%) drugs received any pediatric labeling information. Based on the FDA's Pediatric Molecular Target List, we found that the RACE Act could have increased the proportion of cancer drugs potentially subject to pediatric study requirements from 0% to 78.2%. However, the actual effect of the legislation will depend on how often regulators require pediatric trials and on timely completion of such trials.

Antiparasitic Drugs in the United States-Two Roads to High Prices

High prescription drug prices contribute significantly to healthcare spending in the United States and compromise patients' access to quality medical care. A number of factors allow drug manufacturers to set much higher prices in the US than in other comparable high-income nations. Price-control depends primarily on the entry and persistence of generic products following the expiration of the market exclusivity period granted to the manufacturer of the brand name drug. Unfortunately, barriers to generic entry are common, allowing off-patent drugs like albendazole to remain relatively expensive despite having been marketed in the US for decades. By contrast, miltefosine became FDA approved more recently and has maintained a high price tag by way of a novel incentive program-the neglected tropical disease (NTD) priority review voucher (PRV) program. The voucher has a high market value and can be sold or transferred well before the drug for which it was awarded becomes available on the market. While both drugs are used to treat parasitic infections that are uncommon in the US, they differ by market and regulatory conditions-each telling an interesting pricing story.

Noncompletion and nonpublication of trials studying rare diseases: A cross-sectional analysis

BACKGROUND

Rare diseases affect as many as 60 million people in the United States and Europe. However, most rare diseases lack effective therapies and are in critical need of clinical research. Our objective was to determine the frequency of noncompletion and nonpublication of trials studying rare diseases.

METHODS AND FINDINGS

We conducted a cross-sectional analysis of randomized clinical trials studying rare diseases as defined by the Genetic and Rare Disease Information Center database that were registered in ClinicalTrials.gov between January 1, 2010, and December 31, 2012, and completed or discontinued by December 31, 2014. Our main outcome measures were the frequency of trial noncompletion and, among completed studies, frequency of trial nonpublication at 2 and 4 years following trial completion. Reasons for discontinuation were extracted from the registry, and trial sponsors were contacted for additional information, as needed. Two independent investigators performed publication searches for each trial in PubMed, EMBASE, and GoogleScholar, allowing for a minimum of 45 months between trial completion and publication. When a publication could not be identified, trial sponsors were contacted to confirm publication status. The impact of funding source on trial noncompletion was assessed with multivariable logistic regression, and the effect on time to publication was examined with Cox proportional hazards regression. Control variables included intervention type, trial phase, masking, enrollment, and study population. We analyzed 659 rare disease trials accounting for 70,305 enrolled patients. Industry was the primary funder for 327 trials (49.6%) and academic institutions for 184 trials (27.9%). There were 79 trials (12.0%) focused on pediatric populations. A total of 199 trials (30.2%) were discontinued. Lack of patient accrual (n = 64, 32.1%) and informative termination (n = 41, 20.6%) were the most common reasons for trial noncompletion. Among completed trials, 306 (66.5%) remained unpublished at 2 years and 142 (31.5%) at 4 years. In multivariable analyses, industry-funded trials were less likely to be discontinued than trials funded by healthcare centers (odds ratio [OR] 2.42; 95% confidence interval [CI] 1.34-4.39, P = 0.003). We found no significant association between funding source and time to publication. A total of 18,148 patients were enrolled in trials that were discontinued or unpublished 4 years after completion. A potential limitation of our study is that certain interventional trials for rare diseases may not have been registered in ClinicalTrials.gov, in particular Phase 0 and Phase I trials, which are not required to be registered.

CONCLUSIONS

In this study, over half of clinical trials initiated for rare diseases were either discontinued or not published 4 years after completion, resulting in large numbers of patients with rare diseases exposed to interventions that did not lead to informative findings. Concerted efforts are needed to ensure that participation of patients in rare disease trials advances scientific knowledge and treatments for rare diseases.