Adopting orphan drugs--two dozen years of treating rare diseases

Preparing for the future of precision medicine: synthetic cell drug regulation

Synthetic cells are a novel class of cell-like bioreactors, offering the potential for unique advancements in synthetic biology and biomedicine. To realize the potential of those technologies, synthetic cell-based drugs need to go through the drug approval pipeline. Here, we discussed several regulatory challenges, both unique to synthetic cells, as well as challenges typical for any new biomedical technology. Overcoming those difficulties could bring transformative therapies to the market and will create a path to the development and approval of cutting-edge synthetic biology therapies. Graphical Abstract.

Pharmaceutical policy and innovation for rare diseases: A narrative review

This article aims to synthesize the existing literature on the implementation of public policies to incentivize the development of treatments for rare diseases, (diseases with very low prevalence and therefore with low commercial interest) otherwise known as orphan drugs. The implementation of these incentives in the United States (US), Japan, and in the European Union (EU) seems to be related to a substantial increase in treatments for these diseases, and has influenced the way the pharmaceutical research & development (R&D) system operates beyond this policy area. Despite the success of the Orphan Drug model, the academic literature also highlights the negative implications that these public policies have on affordability and access to orphan drugs, as well as on the prioritization of certain disease rare areas over others. The synthesis focuses mostly on the United States' Orphan Drug Act (ODA) as a model for subsequent policies in other regions and countries. It starts with a historical overview of the creation of the term "rare diseases", continues with a summary of the evidence available on the US ODA's positive and negative impacts, and provides a summary of the different proposals to reform these incentives in light of the negative outcomes described. Finally, it describes some key aspects of the Japanese and European policies, as well as some of the challenges captured in the literature related to their impact in Low- and Middle-Income Countries (LMICs).

European Academy of Neurology guidance for developing and reporting clinical practice guidelines on rare neurological diseases

BACKGROUND AND PURPOSE

Rare diseases affect up to 29 million people in the European Union, and almost 50% of them affect the nervous system or muscles. Delays in diagnosis and treatment onset and insufficient treatment choices are common. Clinical practice guidelines (CPGs) may improve the diagnosis and treatment of patients and optimize care pathways, delivering the best scientific evidence to all clinicians treating these patients. Recommendations are set for developing and reporting high-quality CPGs on rare neurological diseases (RNDs) within the European Academy of Neurology (EAN), through a consensus procedure.

METHODS

A group of 27 experts generated an initial list of items that were evaluated through a two-step Delphi consensus procedure and a face-to-face meeting. The final list of items was reviewed by an external review group of 58 members.

RESULTS

The consensus procedure yielded 63 final items. Items are listed according to the domains of the AGREE instruments and concern scope and purpose, stakeholder involvement, rigour of development, and applicability. Additional items consider reporting and ethical issues. Recommendations are supported by practical examples derived from published guidelines and are presented in two tables: (1) items specific to RND CPGs, and general guideline items of special importance for RNDs, or often neglected; (2) items for guideline development within the EAN.

CONCLUSIONS

This guidance aims to provide solutions to the issues specific to RNDs. This consensus document, produced by many experts in various fields, is considered to serve as a starting point for further harmonization and for increasing the quality of CPGs in the field of RNDs.

The urgent need to empower rare disease organizations in China: an interview-based study

BACKGROUND

Each rare disease only affects a small number of population. However, a total of 7000 rare diseases may affect 10% of the population. Due to the severity and lack of rare disease awareness, rare disease represents a huge challenge for the healthcare system. In Western countries, patient organizations have been playing an integral role in raising awareness, advocating legislation, and supporting drug development. This study aims to assess the unmet needs of rare disease patient organizations in China, and identify their unmet needs, providing essential information for the government and legislators.

RESULTS

A total of 28 individuals representing 28 patient organizations in China were interviewed. Most organizations do not have official registration, employees, written standard operation protocol, or reliable financial resources. Misdiagnosis or delayed diagnosis is common, and treatment is often lacking. Due to the lack of financial resources, no organizations have been able to sponsor academic research, unlike their counterparts in Western countries. As to challenges, 71.4% of interviewees listed lack of rare disease awareness among the general public, while 67.9% selected lack of financial resources. Further, only 7.3% of these organizations received support from the government, and 28.6% received support from the general public. As to recommendations to the government, 82.1% of interviewees selected special insurance programs for rare diseases because rare diseases have been generally excluded from the national medical insurance programs. In addition, 78.6% of interviewees recommended to stimulate rare disease research, 75% recommended to import orphan drugs, and 71.4% recommended legislation of an orphan drug act, highlighting the urgent need of therapies.

CONCLUSIONS

Due to lack of support and rare disease awareness, patient organizations in China are still in the early phase. To empower these patient organizations, the interviewees' recommendations, including legislating orphan drug act and releasing official definition of rare diseases, should be considered by the government and legislators.

Indications for Rituximab Use in an Integrated Health Care Delivery System

BACKGROUND

Rituximab is a top-selling biologic that was first approved by the FDA in 1997 for a non-Hodgkin lymphoma orphan indication. It has since been approved for additional orphan indications, with rheumatoid arthritis as the only FDA-approved, nonorphan indication. Evidence suggests that rituximab is frequently used off-label, but information on its use over time and indications for use in the United States is limited.

OBJECTIVE

To assess incident rituximab use over time in an integrated health care delivery system.

METHODS

This was a cross-sectional, retrospective study. Data were collected from administrative databases and manual chart reviews. Patients who received their first rituximab infusion between October 1, 2009, and December 31, 2017, and who were not a part of a clinical trial were included. Indication for use (FDA-approved orphan/nonorphan, off-label) was determined. Proportions of use were assessed over time. Multivariable logistic regression modeling was performed to assess factors associated with receiving rituximab for an FDA-approved indication.

RESULTS

A total of 1,674 patients were included. The majority (66.4%) of patients had an FDA-approved indication, with lymphoma being the most common approved indication (66.4%). The most common indication for off-label use was neurologic conditions (72.7%), predominantly demyelinating diseases. Off-label indication use increased from 1.2% in 2009 to 55.6% in 2017. Factors associated with rituximab use for an FDA-approved indication included increased age (adjusted odds ratio [AOR] = 1.05, 95% CI = 1.04-1.07) and increased burden of chronic disease (chronic disease score: AOR = 1.07, 95% CI = 1.02-1.12; Charlson Comorbidity Index score: AOR = 3.52, 95% CI = 3.03-4.10).

CONCLUSIONS

Off-label use of rituximab grew dramatically over the course of the study. With the recent FDA approval of the rituximab biosimilar and its expected lower price, off-label use will likely continue to rise. Opportunities for cost savings and to ensure appropriate use of these medications should be evaluated.

DISCLOSURES

This study was funded by Kaiser Permanente. All authors except Hansen are employed by Kaiser Permanente. Hansen has nothing to disclose. Preliminary results were presented at the Mountain States Conference for Residents and Preceptors in May 2019 in Salt Lake City, UT, and at an encore presentation October 2019 at the American College of Clinical Pharmacy Annual Meeting in New York, NY.

Rare Genetic Diseases: Nature's Experiments on Human Development

Rare genetic diseases are the result of a continuous forward genetic screen that nature is conducting on humans. Here, we present epistemological and systems biology arguments highlighting the importance of studying these rare genetic diseases. We contend that the expanding catalog of mutations in ∼4,000 genes, which cause ∼6,500 diseases and their annotated phenotypes, offer a wide landscape for discovering fundamental mechanisms required for human development and involved in common diseases. Rare afflictions disproportionately affect the nervous system in children, but paradoxically, the majority of these disease-causing genes are evolutionarily ancient and ubiquitously expressed in human tissues. We propose that the biased prevalence of childhood rare diseases affecting nervous tissue results from the topological complexity of the protein interaction networks formed by ubiquitous and ancient proteins encoded by childhood disease genes. Finally, we illustrate these principles discussing Menkes disease, an example of the discovery power afforded by rare diseases.

Performance of matching methods in studies of rare diseases: a simulation study

Matching is a common method of adjusting for confounding in observational studies. Studies in rare diseases usually include small numbers of exposed subjects, but the performance of matching methods in such cases has not been evaluated thoroughly. In this study, we compare the performance of several matching methods when number of exposed subjects is small. We used Monte Carlo simulations to compare the following methods: Propensity score matching (PSM) with greedy or optimal algorithm, Mahalanobis distance matching, and mixture of PSM and exact matching. We performed the comparisons in datasets with six continuous and six binary variables, with varying effect size on group assignment and outcome. In each case, there were 1,500 unexposed subjects and a varying number of exposed: N = 25, 50, 100, 150, 200, 250, or 300. The probability of outcome in unexposed subjects was set to 5% (rare), 20% (common), or 50% (frequent). We compared the methods based on the bias of estimate of risk difference, coverage of 95% confidence intervals for risk difference, and balance of covariates. We observed a difference in performance of matching methods in very small samples (N = 25-50) and in moderately small samples (N = 100-300). Our study showed that PSM performs better than other matching methods when number of exposed subjects is small, but the matching algorithm and the matching ratio should be considered carefully. We recommend using PSM with optimal algorithm and one-to-five matching ratio in very small samples, and PSM matching with any algorithm and one-to-one matching in moderately small samples.

Review: Understanding Rare Genetic Diseases in Low Resource Regions Like Jammu and Kashmir - India

Rare diseases (RDs) are the clinical conditions affecting a few percentage of individuals in a general population compared to other diseases. Limited clinical information and a lack of reliable epidemiological data make their timely diagnosis and therapeutic management difficult. Emerging Next-Generation DNA Sequencing technologies have enhanced our horizons on patho-physiological understanding of many of the RDs and ushered us into an era of diagnostic and therapeutic research related to this ignored health challenge. Unfortunately, relevant research is meager in developing countries which lack a reliable estimate of the exact burden of most of the RDs. India is to be considered as the "Pandora's Box of genetic disorders." Owing to its huge population heterogeneity and high inbreeding or endogamy rates, a higher burden of rare recessive genetic diseases is expected and supported by the literature findings that endogamy is highly detrimental to health as it enhances the degree of homozygosity of recessive alleles in the general population. The population of a low resource region Jammu and Kashmir (J&K) - India, is highly inbred. Some of its population groups variably practice consanguinity. In context with the region's typical geographical topography, highly inbred population structure and unique but heterogeneous gene pool, a huge burden of known and uncharacterized genetic disorders is expected. Unfortunately, many suspected cases of genetic disorders remain undiagnosed or misdiagnosed due to lack of appropriate clinical as well as diagnostic resources in the region, causing patients to face a huge psycho-socio-economic crisis and many a time suffer life-long with their ailment. In this review, the major challenges associated with RDs are highlighted in general and an account on the methods that can be adopted for conducting fruitful molecular genetic studies in genetically vulnerable and low resource regions is also provided, with an example of a region like J&K - India.

Systematic Review and Meta-Analysis of the Magnitude of Structural, Clinical, and Physician and Patient Barriers to Cancer Clinical Trial Participation

BACKGROUND

Barriers to cancer clinical trial participation have been the subject of frequent study, but the rate of trial participation has not changed substantially over time. Studies often emphasize patient-related barriers, but other types of barriers may have greater impact on trial participation. Our goal was to examine the magnitude of different domains of trial barriers by synthesizing prior research.

METHODS

We conducted a systematic review and meta-analysis of studies that examined the trial decision-making pathway using a uniform framework to characterize and quantify structural (trial availability), clinical (eligibility), and patient/physician barrier domains. The systematic review utilized the PubMed, Google Scholar, Web of Science, and Ovid Medline search engines. We used random effects to estimate rates of different domains across studies, adjusting for academic vs community care settings.

RESULTS

We identified 13 studies (nine in academic and four in community settings) with 8883 patients. A trial was unavailable for patients at their institution 55.6% of the time (95% confidence interval [CI] = 43.7% to 67.3%). Further, 21.5% (95% CI = 10.9% to 34.6%) of patients were ineligible for an available trial, 14.8% (95% CI = 9.0% to 21.7%) did not enroll, and 8.1% (95% CI = 6.3% to 10.0%) enrolled. Rates of trial enrollment in academic (15.9% [95% CI = 13.8% to 18.2%]) vs community (7.0% [95% CI = 5.1% to 9.1%]) settings differed, but not rates of trial unavailability, ineligibility, or non-enrollment.

CONCLUSIONS

These findings emphasize the enormous need to address structural and clinical barriers to trial participation, which combined make trial participation unachievable for more than three of four cancer patients.

How Often are Orphan Drugs Orphaned by the Thermochemical Community?

Orphan drug products (e.g. drugs and biologics) in the United States are those that treat people with rare chronic diseases, often cancer or metabolic disease. The rare disease condition being treated by these orphan drugs must serve a patient population of less than 200,000 people in the U.S. in order to earn the orphan drug product title. Just as the disease conditions are seen as "orphans," so, we assert is the thermochemical understanding of the drugs themselves in terms of the chemical structures that define those drugs. This article illustrates this orphan thermochemical status for a recent series of orphan drugs.

Administration of gamma-hydroxybutyrate instead of beta-hydroxybutyrate to a liver transplant recipient suffering from propionic acidemia and cardiomyopathy: A case report on a medication prescribing error

Beta‐hydroxybutyrate (BHB) is a synthetic ketone body used as an adjuvant energy substrate in the treatment of patients with metabolic cardiomyopathy. A medication prescribing error led to the administration of the general anesthetic sodium gamma‐hydroxybutyrate (GHB) instead of sodium BHB in a liver transplant recipient with propionic acidemia and cardiomyopathy, causing acute coma. A 15‐year‐old boy suffering from neonatal propionic acidemia underwent liver transplantation (LT) for metabolic decompensation and cardiomyopathy (treated with cardiotropic drugs and BHB) diagnosed a year previously. The patient had been rapidly extubated after LT, and was recovering well. Eight days after LT, the patient suddenly became comatose. No metabolic, immunological, hypertensive, or infectious complications were apparent. The brain magnetic resonance imaging and electroencephalography results were normal. The coma was soon attributed to a medication prescribing error: administration of GHB instead of BHB on day 8 post‐LT. The patient recovered fully within a few hours of GHB withdrawal. The computerized prescription system had automatically suggested the referenced anesthetic GHB (administered intravenously) instead of the non‐referenced ketone body BHB, triggering coma in our patient. A computerized prescription system generated a medication prescribing error for a rare disease, in which the general anesthetic GHB was mistaken for the nonreferenced energy substrate BHB.

The Role of the Food and Drug Administration in Drug Development: On the Subject of Proarrhythmia Risk

The Food and Drug Administration (FDA) is responsible for the regulation of the pharmaceutical industry in the interest of protecting public health. The aim of this review was to outline the evolution and current role of the FDA in the development and approval of new drugs. Additionally, we describe current assessments of proarrhythmia risk to illustrate recent FDA initiatives intended to harness information technology to modernize the regulatory process. In order to identify the literature required to produce this review, search tools such as PubMed and Google Scholar were used to locate relevant web pages and articles. The job of the FDA is not only to ensure that high standards for drug efficacy and safety are applied to products available to American consumers and patients but also to balance the lengthy, costly process of maintaining these standards against the pressure to provide access to effective treatments earlier and without surplus expenditures. In order to provide expedited access to the newest effective therapies for critically ill patients in the safest way possible, the FDA has developed several accelerated pathways to fast-track drug approval. Through partnerships with industry and academic institutions, research is being conducted into how information technology can be integrated into the drug development process to improve its cost-effectiveness.

Strategies for eliciting and synthesizing evidence for guidelines in rare diseases

Background

Rare diseases are a global public health priority. Though each disease is rare, when taken together the thousands of known rare diseases cause significant morbidity and mortality, impact quality of life, and confer a social and economic burden on families and communities. These conditions are, by their nature, encountered very infrequently by individual clinicians, who may feel unprepared to address their diagnosis and treatment. Clinical practice guidelines are necessary to support clinical and policy decisions. However, creating guidelines for rare diseases presents specific challenges, including a paucity of high certainty evidence to inform panel recommendations.

Methods

This paper draws from the authors’ experience in the development of clinical practice guidelines for three rare diseases: hemophilia, sickle cell disease, and catastrophic antiphospholipid syndrome.

Results

We have summarized a number of strategies for eliciting and synthesizing evidence that are compatible with the rigorous, internationally accepted standards for guideline development set out by the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. These strategies include: use of pre-existing and ad hoc qualitative research, use of systematic observation forms, use of registry data, and thoughtful use of indirect evidence. Their use in three real guideline development efforts, as well as their theoretical underpinnings, are discussed. Avenues for future research to improve clinical practice guideline creation for rare diseases – and any disease affected by a relative lack of evidence - are also identified.

Conclusions

Rigorous clinical practice guidelines are needed to improve the care of the millions of people worldwide who suffer from rare diseases. Innovative evidence elicitation and synthesis methods will benefit not only the rare disease community, but also individuals with common diseases who have rare presentations, suffer rare complications, or require nascent therapies. Further refinement and improved uptake of these innovative methods should lead to higher quality clinical practice guidelines in rare diseases.

Effect of Mexiletine on Muscle Stiffness in Patients With Nondystrophic Myotonia Evaluated Using Aggregated N-of-1 Trials

IMPORTANCE

In rare diseases it is difficult to achieve high-quality evidence of treatment efficacy because of small cohorts and clinical heterogeneity. With emerging treatments for rare diseases, innovative trial designs are needed.

OBJECTIVE

To investigate the effectiveness of mexiletine in nondystrophic myotonia using an aggregated N-of-1 trials design and compare results between this innovative design and a previously conducted RCT.

DESIGN, SETTING, AND PARTICIPANTS

A series of aggregated, double-blind, randomized, placebo-controlled N-of-1-trials, performed in a single academic referral center. Thirty Dutch adult patients with genetically confirmed nondystrophic myotonia (38 patients screened) were enrolled between February 2014 and June 2015. Follow-up was completed in September 2016.

INTERVENTIONS

Mexiletine (600 mg daily) vs placebo during multiple treatment periods of 4 weeks.

MAIN OUTCOMES AND MEASURES

Reduction in daily-reported muscle stiffness on a scale of 1 to 9, with higher scores indicating more impairment. A Bayesian hierarchical model aggregated individual N-of-1 trial data to determine the posterior probability of reaching a clinically meaningful effect of a greater than 0.75-point difference.

RESULTS

Among 30 enrolled patients (mean age, 43.4 [SD, 15.24] years; 22% men; 19 CLCN1 and 11 SCN4A genotype), 27 completed the study and 3 dropped out (1 because of a serious adverse event). In 24 of the 27 completers, a clinically meaningful treatment effect was found. In the Bayesian hierarchical model, mexiletine resulted in a 100% posterior probability of reaching a clinically meaningful reduction in self-reported muscle stiffness for the nondystrophic myotonia group overall and the CLCN1 genotype subgroup and 93% posterior probability for the SCN4A genotype subgroup. In the total nondystrophic myotonia group, the median muscle stiffness score was 6.08 (interquartile range, 4.71-6.80) at baseline and was 2.50 (95% credible interval [CrI], 1.77-3.24) during the mexiletine period and 5.56 (95% CrI, 4.73-6.39) during the placebo period; difference in symptom score reduction, 3.06 (95% CrI, 1.96-4.15; n = 27) favoring mexiletine. The most common adverse event was gastrointestinal discomfort (21 mexiletine [70%], 1 placebo [3%]). One serious adverse event occurred (1 mexiletine [3%]; allergic skin reaction). Using frequentist reanalysis, mexiletine compared with placebo resulted in a mean reduction in daily-reported muscle stiffness of 3.12 (95% CI, 2.46-3.78), consistent with the previous RCT treatment effect of 2.69 (95% CI, 2.12-3.26).

CONCLUSIONS AND RELEVANCE

In a series of N-of-1 trials of mexiletine vs placebo in patients with nondystrophic myotonia, there was a reduction in mean daily-reported muscle stiffness that was consistent with the treatment effect in a previous randomized clinical trial. These findings support the efficacy of mexiletine for treatment of nondystrophic myotonia as well as the feasibility of N-of-1 trials for assessing interventions in some chronic rare diseases.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02045667.

Investigating the landscape of US orphan product approvals

Background

The Orphan Drug Act was enacted in 1983 to encourage the development of drugs for rare diseases. Previous research has attempted to examine the impact of the Act by assessing either the number of orphan designations that have been granted or the number of new orphan drugs approved for marketing. This study provides a more in-depth understanding of the effect of the Orphan Drug Act by investigating all types of drug approvals with an orphan designation, along with multiple characteristics of the drugs, over the entire 35 years of the Act. These orphan approvals include: new molecular entities (new drugs approved first for a rare disease), secondary indications (an expansion from the first approved indication), and new formulations.

Results

The results show that the number of approvals for orphan indications has been increasing over time, and the upward trend is especially large in the most recent years. Much of this increase has been driven by the increase in secondary indications being approved for previously approved drugs, although there have also been increases in the number of approved new drugs. We also find that while oncology indications have been increasing significantly, there has also been an increase in other therapeutic areas. Additionally, we find that the proportion of biologic drugs being approved has increased over time. Lastly, while other parts of this drug landscape have dramatically altered over time, the proportion of orphan approvals receiving priority review has not changed.

Conclusions

Our data suggest that the Orphan Drug Act appears to have stimulated significant drug development for rare diseases. Additionally, approvals of orphan indications have been increasing over time. This increasing effect has not targeted a single area of the rare disease space, rather, gains in approvals have been seen across: therapeutic areas, approval types (both new drugs and secondary indications), and for both biologics and small molecule drugs.

Electronic supplementary material

The online version of this article (10.1186/s13023-018-0930-3) contains supplementary material, which is available to authorized users.

Can Severity Outweigh Smaller Numbers? A Deliberative Perspective from Canada

OBJECTIVES

To use structured deliberation to elicit and describe the values of the public in Alberta, Canada, on the question of whether the severity of a rare condition can justify it being given priority in funding over common conditions affecting larger numbers of patients, and what aspects of a condition drive this judgment.

METHODS

Thematic analysis of transcripts of a group deliberative exercise carried out as part of two citizens' juries. The exercise was designed to elicit participants' conception of disease severity, and trade-offs between helping small groups with severe conditions and larger groups with less severe conditions.

RESULTS

In trading off severity and numbers, all groups were willing to choose a more severely ill but smaller group of patients over a less severely ill but larger group of patients, although how much of a severity differential was required varied between groups. Pain that could not be relieved by alternative means was the strongest motivator for choosing the smaller group. Other symptoms with no alternative means of relief were strong motivators as well.

CONCLUSIONS

These findings indicate that, all else being equal, the public would support giving priority to a smaller but more severely ill group of patients over a larger group when prioritizing the needs of the few is life-saving, extends life enough to give hope of future improvement, and relieves otherwise intractable symptoms, especially pain.

Harnessing the Digital Exhaust: Incorporating wellness into the pharma model

The increasing availability of devices capable of tracking biomarkers presents major opportunities in contemporary healthcare. Herein we advocate a new role for the pharmaceutical industry to capitalize on these opportunities and in doing so incorporate wellness and patient engagement programs into their standard business models. Medical grade decision making using diagnostic, prognostic, and monitoring biomarkers will require coordinated approaches between the pharmaceutical and technology industries and the careful design of longitudinal clinical studies to validate their efficacy. These studies will also require data capture, archiving, curating and sharing on a previously unprecedented scale, and raise additional concerns with regard to data security and ownership. Concurrently, systems-based approaches to the capture and interpretation of a new class of digital biomarkers are emerging, and hold promise for heightened levels of patient engagement and remote sensing. Collectively, if these new opportunities are approached within the context of the patient-provider ecosystem, major repositioning of the pharmaceutical industry may be possible in the near term.

Planning Future Clinical Trials for Machado-Joseph Disease

Spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD) is an autosomal dominant multiple neurological systems degenerative disorder caused by a CAG repeat expansion at ATXN3 gene. Only a few treatments were evaluated in randomized clinical trials (RCT) in SCA3/MJD patients, with a lack of evidence for both disease-modifying and symptomatic therapies. The present chapter discuss in detail major methodological issues for planning future RCT for SCA3/MJD. There are several potential therapies for SCA3/MJD with encouraging preclinical results. Route of treatment, dosage titration and potential therapy biomarkers might differ among candidate drugs; however, the core study design and protocol will be mostly the same. RCT against placebo group is the best study design to test a disease-modifying therapy; the same cannot be stated for some symptomatic treatments. Main outcomes for future RCT are clinical scales: the Scale for the Assessment and Rating of ataxia (SARA) is currently the instrument of choice to prove efficacy of disease-modifying or symptomatic treatments against ataxia, the most important disease feature. Ataxia quantitative scales or its composite scores can be used as primary outcomes to provide preliminary evidence of efficacy in phase 2 RCT, due to a greater sensitivity to change. Details regarding eligibility criteria, randomization, sample size estimation, duration and type of analysis for both disease modifying and symptomatic treatment trials, were also discussed. Finally, a section anticipates the methodological issues for testing novel drugs when an effective treatment is already available. We conclude emphasizing four points, the first being the need of RCT for a number of different aims in the care of SCA3/MJD. Due to large sample sizes needed to warrant power, RCT for disease-modifying therapies should be multicenter enterprises. There is an urge need for surrogate markers validated for several drug classes. Finally, engagement of at risk or presymptomatic individuals in future trials will enable major advances on treatment research for SCA3/MJD.

Computational drug repositioning for rare diseases in the era of precision medicine

There are tremendous unmet needs in drug development for rare diseases. Computational drug repositioning is a promising approach and has been successfully applied to the development of treatments for diseases. However, how to utilize this knowledge and effectively conduct and implement computational drug repositioning approaches for rare disease therapies is still an open issue. Here, we focus on the means of utilizing accumulated genomic data for accelerating and facilitating drug repositioning for rare diseases. First, we summarize the current genome landscape of rare diseases. Second, we propose several promising bioinformatics approaches and pipelines for computational drug repositioning for rare diseases. Finally, we discuss recent regulatory incentives and other enablers in rare disease drug development and outline the remaining challenges.

Drug discovery and development for rare genetic disorders

Approximately 7,000 rare diseases affect millions of individuals in the United States. Although rare diseases taken together have an enormous impact, there is a significant gap between basic research and clinical interventions. Opportunities now exist to accelerate drug development for the treatment of rare diseases. Disease foundations and research centers worldwide focus on better understanding rare disorders. Here, the state-of-the-art drug discovery strategies for small molecules and biological approaches for orphan diseases are reviewed. Rare diseases are usually genetic diseases; hence, employing pharmacogenetics to develop treatments and using whole genome sequencing to identify the etiologies for such diseases are appropriate strategies to exploit. Beginning with high throughput screening of small molecules, the benefits and challenges of target-based and phenotypic screens are discussed. Explanations and examples of drug repurposing are given; drug repurposing as an approach to quickly move programs to clinical trials is evaluated. Consideration is given to the category of biologics which include gene therapy, recombinant proteins, and autologous transplants. Disease models, including animal models and induced pluripotent stem cells (iPSCs) derived from patients, are surveyed. Finally, the role of biomarkers in drug discovery and development, as well as clinical trials, is elucidated.

Do investors value the FDA orphan drug designation?

Background

The Orphan Drug Act is an important piece of legislation that uses financial incentives to encourage the development of drugs that treat rare diseases. This analysis studies the effects of a portion of the Orphan Drug Act, the orphan drug designation. Specifically, it studies the value that investors place on the orphan drug designation, by investigating how investors react to companies’ announcing that their product has received the designation.

Results

The results, on average, show that the stock price of a company increases by 3.36% after the announcement of the designation, increasing the value of the company. The results are more pronounced for oncology drugs, and drugs being developed by the smallest companies.

Conclusion

The orphan designation appears to be successful at generating positive value for companies, as seen by the positive and significant average increases in stock price.

Electronic supplementary material

The online version of this article (doi:10.1186/s13023-017-0665-6) contains supplementary material, which is available to authorized users.

Drug development challenges and strategies to address emerging and resistant fungal pathogens

INTRODUCTION

Invasive fungal infections represent an expanding threat to public health. The recent emergence of Candida auris, which is often resistant to existing antifungal agents and is associated with a high mortality rate, underscores the urgent need for novel drug development strategies. Areas covered: In this paper, we examine both challenges and opportunities associated with antifungal drug development and explore potential avenues to accelerate the development pipeline, including data sharing, surrogate endpoints, and the role of historical controls in clinical trials. Expert commentary: We review important lessons learned from the study of other rare diseases, including mitochondrial storage diseases and certain forms of cancer that may inform strategies to develop new antifungal agents while highlighting promising new compounds such as SCY-078 for the treatment of invasive fungal infections.

[Orphan drugs : New opportunities for the treatment of rare diseases]

Not only in Europe and USA, but also in many other countries rare disorders-so-called orphan diseases-have attracted more and more attention. The formation of specialized centers for rare disorders has enabled the diagnosis of diseases that have been widely unknown before. In addition, pharmaceutical companies have recognized orphan diseases as a profitable source of revenue. The development and marketing of new drugs for rare diseases-so-called orphan diseases-means a great challenge for all who participate in the health care system: Because the number of patients who are available for a clinical study is mostly very small, it is often very difficult or even impossible to show statistically firm evidence of efficacy. The standard placebo-controlled, double-blind clinical trial is often inappropriate for the approval procedure of an orphan drug; thus other study designs or other parameters (e.g. biomarkers) have to be used to prove clinical efficacy of the study drug. Only relatively small amounts of drugs can be sold to the generally few patients affected by an orphan disease and clinical trials require an high amount of financial investment; therefore orphan drugs have in general extremely high prices. How long these high expenses can be borne by the health care system in view of the great number of rare diseases remains questionable.

Profitability and Market Value of Orphan Drug Companies: A Retrospective, Propensity-Matched Case-Control Study

Background

Concerns about the high cost of orphan drugs has led to questions being asked about the generosity of the incentives for development, and associated company profits.

Methods

We conducted a retrospective, propensity score matched study of publicly-listed orphan companies. Cases were defined as holders of orphan drug market authorisation in Europe or the USA between 2000–12. Control companies were selected based on their propensity for being orphan drug market authorisation holders. We applied system General Method of Moments to test whether companies with orphan drug market authorization are valued higher, as measured by the Tobin’s Q and market to book value ratios, and are more profitable based on return on assets, than non-orphan drug companies.

Results

86 companies with orphan drug approvals in European (4), USA (61) or both (21) markets were matched with 258 controls. Following adjustment, orphan drug market authorization holders have a 9.6% (95% confidence interval, 0.6% to 18.7%) higher return on assets than non-orphan drug companies; Tobin’s Q was higher by 9.9% (1.0% to 19.7%); market to book value by 15.7% (3.1% to 30.0%) and operating profit by 516% (CI 19.8% to 1011%). For each additional orphan drug sold, return on assets increased by 11.1% (0.6% to 21.3%), Tobin’s Q by 2.7% (0.2% to 5.2%), and market to book value ratio by 5.8% (0.7% to 10.9%).

Conclusions

Publicly listed pharmaceutical companies that are orphan drug market authorization holders are associated with higher market value and greater profits than companies not producing treatments for rare diseases.

Novel Treatments for Rare Cancers: The U.S. Orphan Drug Act Is Delivering-A Cross-Sectional Analysis

BACKGROUND

Rare cancers are a heterogeneous group of conditions with highly unmet medical needs. Although infrequent in individuals, rare cancers affect millions of people who deserve effective treatments. Therefore, we systematically analyzed the impact of the U.S. Orphan Drug Act of 1983 on delivery of novel treatments for rare cancers.

METHODS

Quantitative cross-sectional analysis was conducted on the U.S. Food and Drug Administration Orphan Drug Product database according to Strengthening the Reporting of Observational Studies in Epidemiology Statement criteria between 1983 and 2015.

RESULTS

Since 1983, a total of 177 approvals have originated from 1,391 orphan drug designations to treat rare cancers, which represents 36% of all approvals within the U.S. orphan drug act (n = 492). Two compounds (1%) to treat rare cancer were withdrawn after approval. Median time from designation to approval was 2.49 years (interquartile range 1.13-4.64) and decreased significantly over time (p < .001, linear regression). Over the last decade, rare cancer treatments have been transformed from nonspecific cytotoxic agents toward targeted therapies, such as protein kinase inhibitors and monoclonal antibodies, representing the largest groups of innovative rare cancer treatments today. Most compounds were approved to treat solid tumors and hematological malignancies.

CONCLUSION

The U.S. Orphan Drug Act and associated incentives, such as 7 years of marketing exclusivity, have fostered delivery of novel treatments for rare cancers. More than one-third of all orphan drug approvals address needs of patients suffering from rare cancers. Over the last decade, the understanding of tumorigenesis and genetic driver mutations in different tumor entities has produced innovative treatments, of which many were first approved within the U.S. Orphan Drug Act.

IMPLICATIONS FOR PRACTICE

Over the last 30 years, the U.S. Orphan Drug Act successfully delivered numerous novel treatments for rare cancers, of which some were subsequently used in other, nonorphan indications. The understanding of molecular mechanisms of diseases is directly connected to the search for novel therapies. The constant pursuit to translate basic research findings into clinical practice is a crucial prerequisite to address unmet medical needs in rare cancers, as in other rare diseases. Oncological drug development proves to be a major player in overall orphan drug research, displayed by more than one-third of all U.S. Food and Drug Administration-approved orphan drugs with oncological indications.

Changing the Paradigm for the Treatment and Development of New Therapies for FSGS

Focal segmental glomerulosclerosis (FSGS) is a renal pathology finding that represents a constellation of rare kidney diseases, which manifest as proteinuria, edema nephrotic syndrome, hypertension, and increased risk for kidney failure. Therapeutic options for FSGS are reviewed displaying the expected efficacy from 25 to 69% depending on specific therapy, patient characteristics, cost, and common side effects. This variability in treatment response is likely caused, in part, by the heterogeneity in the etiology and active molecular mechanisms of FSGS. Clinical trials in FSGS have been scant in number and slow to recruit, which may stem, in part, from reliance on classic clinical trial design paradigms. Traditional clinical trial designs based on the "learn and confirm" paradigm may not be appropriate for rare diseases, such as FSGS. Future drug development and testing will require novel approaches to trial designs that have the capacity to enrich study populations and adapt the trial in a planned way to gain efficiencies in trial completion timelines. A clinical trial simulation is provided that compares a classical and more modern design to determine the maximum tolerated dose in FSGS.

Developing methodology for the creation of clinical practice guidelines for rare diseases: A report from RARE-Bestpractices

Rare diseases are a global public health priority; they can cause significant morbidity and mortality, can gravely affect quality of life, and can confer a social and economic burden on families and communities. These conditions are, by their nature, encountered very infrequently by clinicians. Thus, clinical practice guidelines are potentially very helpful in supporting clinical decisions, health policy and resource allocation. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system is a structured and transparent approach to developing and presenting summaries of evidence, grading its quality, and then transparently interpreting the available evidence to make recommendations in health care. GRADE has been adopted widely. However, its use in creating guidelines for rare diseases – which are often plagued by a paucity of high quality evidence – has not yet been explored. RARE-Bestpractices is a project to create and populate a platform for sharing best practices for management of rare diseases. A major aim of this project is to ensure that European Union countries have the capacity to produce high quality clinical practice guidelines for rare diseases. On February 12, 2013 at the Istituto Superiore di Sanità, in Rome, Italy, the RARE-Bestpractices group held the first of a series of 2 workshops to discuss methodology for creating clinical practice guidelines, and explore issues specific to rare diseases. This paper summarizes key results of the first workshop, and explores how the current GRADE approach might (or might not) work for rare diseases. Avenues for future research are also identified.

Rare Disease Terminology and Definitions-A Systematic Global Review: Report of the ISPOR Rare Disease Special Interest Group

BACKGROUND

At present, there is no universal definition of rare disease.

OBJECTIVE

To provide an overview of rare disease definitions currently used globally.

METHODS

We systematically searched for definitions related to rare disease from organizations in 32 international jurisdictions. Descriptive statistics of definitions were generated and prevalence thresholds were calculated.

RESULTS

We identified 296 definitions from 1109 organizations. The terms "rare disease(s)" and "orphan drug(s)" were used most frequently (38% and 27% of the definitions, respectively). Qualitative descriptors such as "life-threatening" were used infrequently. A prevalence threshold was specified in at least one definition in 88% of the jurisdictions. The average prevalence threshold across organizations within individual jurisdictions ranged from 5 to 76 cases/100,000 people. Most jurisdictions (66%) had an average prevalence threshold between 40 and 50 cases/100,000 people, with a global average of 40 cases/100,000 people. Prevalence thresholds used by different organizations within individual jurisdictions varied substantially. Across jurisdictions, umbrella patient organizations had the highest (most liberal) average prevalence threshold (47 cases/100,000 people), whereas private payers had the lowest threshold (18 cases/100,000 people).

CONCLUSIONS

Despite variation in the terminology and prevalence thresholds used to define rare diseases among different jurisdictions and organizations, the terms "rare disease" and "orphan drug" are used most widely and the average prevalence threshold is between 40 and 50 cases/100,000 people. These findings highlight the existing diversity among definitions of rare diseases, but suggest that any attempts to harmonize rare disease definitions should focus on standardizing objective criteria such as prevalence thresholds and avoid qualitative descriptors.

Value-based reimbursement decisions for orphan drugs: a scoping review and decision framework

BACKGROUND

The rate of development of new orphan drugs continues to grow. As a result, reimbursing orphan drugs on an exceptional basis is increasingly difficult to sustain from a health system perspective. An understanding of the value that societies attach to providing orphan drugs at the expense of other health technologies is now recognised as an important input to policy debates.

OBJECTIVES

The aim of this work was to scope the social value arguments that have been advanced relating to the reimbursement of orphan drugs, and to locate these within a coherent decision-making framework to aid reimbursement decisions in the presence of limited healthcare resources.

METHODS

A scoping review of the peer reviewed and grey literature was undertaken, consisting of seven phases: (1) identifying the research question; (2) searching for relevant studies; (3) selecting studies; (4) charting, extracting and tabulating data; (5) analyzing data; (6) consulting relevant experts; and (7) presenting results. The points within decision processes where the identified value arguments would be incorporated were then located. This mapping was used to construct a framework characterising the distinct role of each value in informing decision making.

RESULTS

The scoping review identified 19 candidate decision factors, most of which can be characterised as either value-bearing or 'opportunity cost'-determining, and also a number of value propositions and pertinent sources of preference information. We were able to synthesize these into a coherent decision-making framework.

CONCLUSION

Our framework may be used to structure policy discussions and to aid transparency about the values underlying reimbursement decisions for orphan drugs. These values ought to be consistently applied to all technologies and populations affected by the decision.

Toward a functional definition of a "rare disease" for regulatory authorities and funding agencies

BACKGROUND

The designation of a disease as "rare" is associated with some substantial benefits for companies involved in new drug development, including expedited review by regulatory authorities and relaxed criteria for reimbursement. How "rare disease" is defined therefore has major financial implications, both for pharmaceutical companies and for insurers or public drug reimbursement programs. All existing definitions are based, somewhat arbitrarily, on disease incidence or prevalence.

OBJECTIVES

What is proposed here is a functional definition of rare based on an assessment of the feasibility of measuring the efficacy of a new treatment in conventional randomized controlled trials, to inform regulatory authorities and funding agencies charged with assessing new therapies being considered for public funding.

METHODS

It involves a five-step process, involving significant negotiations between patient advocacy groups, pharmaceutical companies, physicians, and public drug reimbursement programs, designed to establish the feasibility of carrying out a randomized controlled trial with sufficient statistical power to show a clinically significant treatment effect.

RESULTS AND CONCLUSIONS

The steps are as follows: 1) identification of a specific disease, including appropriate genetic definition; 2) identification of clinically relevant outcomes to evaluate efficacy; 3) establishment of the inherent variability of measurements of clinically relevant outcomes; 4) calculation of the sample size required to assess the efficacy of a new treatment with acceptable statistical power; and 5) estimation of the difficulty of recruiting an adequate sample size given the estimated prevalence or incidence of the disorder in the population and the inclusion criteria to be used.

Orphan therapies: making best use of postmarket data

BACKGROUND

Postmarket surveillance of the comparative safety and efficacy of orphan therapeutics is challenging, particularly when multiple therapeutics are licensed for the same orphan indication. To make best use of product-specific registry data collected to fulfill regulatory requirements, we propose the creation of a distributed electronic health data network among registries. Such a network could support sequential statistical analyses designed to detect early warnings of excess risks. We use a simulated example to explore the circumstances under which a distributed network may prove advantageous.

METHODS

We perform sample size calculations for sequential and non-sequential statistical studies aimed at comparing the incidence of hepatotoxicity following initiation of two newly licensed therapies for homozygous familial hypercholesterolemia. We calculate the sample size savings ratio, or the proportion of sample size saved if one conducted a sequential study as compared to a non-sequential study. Then, using models to describe the adoption and utilization of these therapies, we simulate when these sample sizes are attainable in calendar years. We then calculate the analytic calendar time savings ratio, analogous to the sample size savings ratio. We repeat these analyses for numerous scenarios.

KEY RESULTS

Sequential analyses detect effect sizes earlier or at the same time as non-sequential analyses. The most substantial potential savings occur when the market share is more imbalanced (i.e., 90% for therapy A) and the effect size is closest to the null hypothesis. However, due to low exposure prevalence, these savings are difficult to realize within the 30-year time frame of this simulation for scenarios in which the outcome of interest occurs at or more frequently than one event/100 person-years.

CONCLUSIONS

We illustrate a process to assess whether sequential statistical analyses of registry data performed via distributed networks may prove a worthwhile infrastructure investment for pharmacovigilance.

When everyone is an orphan: against adopting a U.S.-styled orphan drug policy in Canada

Putting aside whether diseases that affect only small numbers of people ("rare diseases") should be prioritized over diseases that are otherwise orphaned, in this article I argue that a new approach to rare, orphan diseases is needed. The current model, first signaled by the United States' Orphan Drug Act and subsequently emulated by several other jurisdictions, relies on a set of open-ended criteria and market-based incentives in order to define and encourage drug therapies for rare, orphan diseases. Given a) the biopharmaceutical industries' growing interest in orphan diseases, b) progress in the sphere of personalized medicines enabling more and more common diseases to be reclassified as rare, and c) empirical evidence suggesting that the most orphan drugs target only a limited, lucrative subset of rare diseases, I argue that Canada, which recently announced plans to develop its own "orphan drug framework" should not follow the United States' orphan drug model.

The current status of orphan drug development in Europe and the US

Orphan drug legislation has been introduced in a number of countries in order to stimulate the development of treatments for rare diseases by introducing commercial incentives for companies wishing to undertake that development. In order to navigate the maze of regulatory regulations and procedures so that companies can make proper use of the orphan drug incentives, specialist knowledge is required. This article will review the current status of orphan drug development in the EU and the US, explain the incentives and procedures, and touch on the role of patient organisations in the process.

[Court-ordered access to treatment of rare genetic diseases: Fabry Disease in the state of Rio Grande do Sul, Brazil]

Court-ordered access to high-cost drugs for rare genetic diseases, such as Fabry Disease (alpha-galactosidase-A deficiency), is a growing phenomenon as yet lacking systematic study. An observational, cross-sectional and retrospective study was conducted to characterize the lawsuits related to access to treatment for Fabry Disease by Enzyme Replacement Therapy in the State of Rio Grande do Sul prior to 2007. The study identified 13 lawsuits and 17 plaintiffs, 11 requesting alfa and 6 betagalsidase. The State of RS, the Federal Government, and 5 municipalities figured as defendants, in the form of joinder of parties or otherwise. There were 13 requests for interlocutory relief of which 12 were granted, and 2 sentences were handed down, both favorable. "Risk of death" was alleged by doctors in 4 prescriptions and by lawyers in the 13 lawsuits. The data suggest the lack of discussions combining aspects of medical efficacy and safety, cost-effectiveness, economic impact, and legal and constitutional arguments, which requires a specific policy for rare genetic diseases to standardize access to treatment.

Funding innovation for treatment for rare diseases: adopting a cost-based yardstick approach

Background

Manufacturers justify the high prices for orphan drugs on the basis that the associated R&D costs must be spread over few patients. The proliferation of these drugs in the last three decades, combined with high prices commonly in excess of $100,000 per patient per year are placing a substantial strain on the budgets of drug plans in many countries. Do insurers spend a growing portion of their budgets on small patient populations, or leave vulnerable patients without coverage for valuable treatments? We suggest that a third option is present in the form of a cost-based regulatory mechanism.

Methods

This article explores the use of a cost-based price control mechanism for orphan drugs, adapted from the standard models applied in utilities regulation.

Results and conclusions

A rate-of-return style model, employing yardsticked cost allocations and a modified two-stage rate of return calculation could be effective in setting a new standard for orphan drugs pricing. This type of cost-based pricing would limit the costs faced by insurers while continuing to provide an efficient incentive for new drug development.

Clinical studies in lysosomal storage diseases: Past, present, and future

Lysosomal storage disorders (LSDs) consist of over 40 diseases, some of which are amenable to treatment. In this review, we consider the regulatory context in which LSDs studies are performed, highlight design specificities and explore operational challenges.

Orphan drug legislations, both in Europe and US, were effective to stimulate LSDs drug development. However, regulators flexibilities toward approval vary leading to global discrepancies in access to treatments.

Study designs are constrained because few patients can be studied. This implies LSDs treatments need to demonstrate large levels of clinical efficacy. If not, an appropriate level of evidence is difficult to achieve. While biomarkers could address this issue, none have been truly accepted as primary outcome.

Enrichment of study population can increase the chance of success, especially with clinical outcomes. Adaptive designs are operationally challenging. Innovative methods of analysis can be used, notably using a patient as his/her own control and responder analysis. The use of extension phases and patient registries as a source of historical comparison can facilitate data interpretation.

Operationally, few patients are available per centers and multiple centers need to be initiated in multiple countries. This impacts time-lines and budget.

In the future, regulators flexibility will be essential to provide patients access to innovative treatments.

Emergence of pediatric rare diseases: Review of present policies and opportunities for improvement

In this article we discuss the steps taken by the United States (US) and the European Union (EU) to meet the health care needs of children with rare diseases and suggest possible directions for future endeavors for further improvement. We reviewed 23 reports and nine legislative documents related to pediatric rare diseases and public policy. We assessed the outcome measures of access and satisfaction with medical services by utilizing the surveys done by the European Organization for Rare Diseases -Eurordis (n = 5,963). Comparable surveys were not available in the US. Our analyses of the existing policies and surveys indicate multiple differences between the US and EU. While the US policies seem to be aimed at disease diagnosis and neonatal screening, EU legislators appear to be focusing on access to existing specialized care. However, both systems have struggled with effectively promoting new treatments. Also, while Eurordis surveys have evaluated areas such as the access to medical services, access to social services and satisfaction with the services received in Europe, there are no comparable surveys in the United States. We conclude that better tools are needed to measure the quality of care, needs-assessment and outcome of pediatric rare diseases in both the EU and US. We suggest a better assessment of areas such as access to primary and specialty care, legal advocacy, comfort-care, end-of-life care, social and financial services, psychological support and quality outcome-measures.

Reported numbers of patients with rare diseases based on ten-year longitudinal national disability registries in Taiwan

This paper aims to describe a general demographic picture of patients with rare diseases in Taiwan and particularly focuses on the prevalence of rare diseases over time, age and gender distributions. We analyzed data mainly from the national disability registry from 2002 to 2011 in Taiwan, Republic of China. The results showed that the number of rare diseases increased from 93 to 193 between 2002 and 2011 and that the prevalence of rare diseases increased from 0.02 to 0.74 per 10,000 people in this time period. The gender ratio (male/female) was between 1.02 and 1.13 during this time period, with male cases representing a higher percentage than female cases in the rare disease population. The occurrence of rare diseases was significantly increased in children 3-5 years of age and elementary school children 6-14 years of age. The data also revealed that the occurrence of rare diseases in Taiwan was attributed primarily to pathogenic diseases and secondarily to genetic diseases. To obtain precise epidemiological data on rare diseases for future healthcare planning, this study highlights the importance of the cooperation of healthcare authorities with the social welfare department to strengthen the ability of the public healthcare system to regularly monitor and measure the occurrence of rare diseases in the community.