Challenges in Orphan Drug Development: Identification of Effective Therapy for Thyroid-Associated Ophthalmopathy.

Thyroid-associated ophthalmopathy (TAO), the ocular manifestation of Graves' disease, is a process in which orbital connective tissues and extraocular muscles undergo inflammation and remodeling. The condition seems to result from autoimmune responses to antigens shared by the thyroid and orbit. The thyrotropin receptor (TSHR), expressed at low levels in orbital tissues, is a leading candidate antigen. Recent evidence suggests that another protein, the insulin-like growth factor-I receptor (IGF-IR), is overexpressed in TAO, and antibodies against IGF-IR have been detected in patients with the disease. Furthermore, TSHR and IGF-IR form a physical and functional complex, and signaling initiated at TSHR requires IGF-IR activity. Identification of therapy for this rare disease has proven challenging and currently relies on nonspecific and inadequate agents, thus representing an important unmet need. A recently completed therapeutic trial suggests that inhibiting IGF-IR activity with a monoclonal antibody may be an effective and safe treatment for active TAO.

Innovative design and analysis for rare disease drug development.

One of the most challenges for rare diseases drug development is probably the availability of subjects with the diseases under a small patient population. It is then a great concern how to conduct clinical trials with the limited number of subjects available for obtaining substantial evidence regarding effectiveness and safety for approval of the drug product under investigation. For rare diseases drug development, FDA indicated that the Agency does not have the intention to create a statutory standard for approval of orphan drugs that is different from the standard for approval of drugs in common conditions. In this case, innovative thinking and approach for obtaining substantial evidence for approval of rare diseases drug products are necessarily applied. In this article, basic considerations for rare disease drug development are discussed. The innovative thinking of demonstrating not-ineffectiveness rather than effectiveness with a limited number of subjects available is outlined. In addition, an innovative approach utilizing a two-stage adaptive seamless trial design in conjunction with the concept of real-world data and real-world evidence is proposed not only to obtain substantial evidence for approval of rare diseases drug products, but also to meet the same standard as those drug products in common conditions. Under the two-stage adaptive seamless trial design, sample size calculation for rare diseases clinical trials based on the innovative probability monitoring procedure is also discussed.

Evaluating Canadians' Values for Drug Coverage Decision Making.

BACKGROUND: Decision makers are facing growing challenges in prioritizing drugs for reimbursement because of soaring drug costs and increasing pressures on financial resources. In addition to cost and effectiveness, payers are using other values to dictate which drugs are prioritized for funding, yet there are limited data on the Canadian public's priorities. OBJECTIVES: To measure the relative societal importance of values considered most relevant in informing drug reimbursement decisions in a representative sample of Canadians. METHODS: An online survey of 2539 Canadians aged 19 years and older was performed in which 13 values used in drug funding prioritization were ranked and then weighted using an analytic hierarchy process. RESULTS: Canadians value safe and efficacious drugs that have certainty of evidence. The values ranked in the top 5 by most of our subjects were potential effect on quality of life (65.4%), severity of the disease (62.6%), ability of drug to work (61.1%), safety (60.5%), and potential to extend life (49.4%). Values related to patient or disease characteristics such as rarity, socioeconomic status, and health and lifestyle choices held the lowest rankings and weights. CONCLUSIONS: Canadians value, above all, treatment-related factors (eg, efficacy and safety) and disease-related factors (eg, severity and equity). Decision makers are currently using additional justifications to prioritize drugs for reimbursement, such as rarity and unmet need, which were not found to be highly valued by Canadians. Decision makers should integrate the public's values into a Canadian reimbursement framework for prioritization of drugs competing for limited funds.

Statistical considerations for rare diseases drug development.

One of the most challenges for rare disease clinical trials is probably the availability of a small patient population. It is then a great concern on how to conduct clinical trials with a small number of subjects available for obtaining substantial evidence regarding safety and effectiveness for approval of the rare disease drug product under investigation. FDA, however, does not have the intention to create a statutory standard for approval of orphan drugs that are different from the standard for approval of drugs in common conditions. Thus, it is suggested that innovative trial designs such as a complete n-of-1 trial design or an adaptive design should be used for an accurate and reliable assessment of rare disease drug products under investigation. In this article, basic considerations, innovative trial designs, and statistical methods for data analysis are discussed. In addition, some innovative thinking for the evaluation of rare disease drug products is proposed.

Orphan drug development: the increasing role of clinical pharmacology.

Over the last few decades there has been a paradigm shift in orphan drug research and development. The development of the regulatory framework, establishment of rare disease global networks that support drug developments, and advances in technology, has resulted in tremendous growth in orphan drug development. Nevertheless, several challenges during orphan drug development such as economic constraints; insufficient clinical information; fewer patients and thus inadequate power; etc. still exist. While the standard regulatory requirements for drug approval stays the same, applications of scientific judgment and regulatory flexibility is significantly important to help meeting some of the immense unmet medical need in rare diseases. Clinical pharmacology presents a vital role in accelerating orphan drug development and overcoming some of these challenges. This review highlights the critical contributions of clinical pharmacology in orphan drug development; for example, dose finding, optimizing clinical trial design, indication expansion, and population extrapolation. Examples of such applications are reviewed in this article.

Towards regulatory endorsement of drug development tools to promote the application of model-informed drug development in Duchenne muscular dystrophy.

Drug development for rare diseases is challenged by small populations and limited data. This makes development of clinical trial protocols difficult and contributes to the uncertainty around whether or not a potential therapy is efficacious. The use of data standards to aggregate data from multiple sources, and the use of such integrated databases to develop statistical models can inform protocol development and reduce the risks in developing new therapies. Achieving regulatory endorsement of such models through defined pathways at the US Food and Drug Administration and European Medicines Authority allows such tools to be used by the drug development community for defined contexts of use without further need for discussion of the underlying model(s). The Duchenne Regulatory Science Consortium (D-RSC) has brought together multiple stakeholders to develop a clinical trial simulation tool for Duchenne muscular dystrophy using such an approach. Here we describe the work of D-RSC as an example of how such an approach may be effective at reducing uncertainty in drug development for rare diseases, and thus bringing effective therapies to patients faster.

The impact of orphan drug policies in treating rare diseases.

This paper is based on Shalini Weerasooriya's Masters dissertation in Public Health at the University of Sheffield. A literature review was conducted to understand the role that orphan drug policies have played in the development of new treatments for rare diseases. The impacts of the policies were categorised as 'tangible' or 'intangible' and further synthesis identified 10 main themes such as incentives for investment, criteria for eligibility and assessment of drug applications and further guidance to industry during the drug development cycle. The review concludes that whilst policies have contributed positively towards improving the research and development of orphan drugs it has not exhausted its uses and must now shift its focus to facilitating greater accessibility and affordability of the treatments and that stakeholders are essential to the success of this process. Implications for practice are identified, for example the need to further update and refine the policy with changing demographics and advancing technologies and, in particular, greater collaboration and involvement through, for example, evidence based training programmes is recommended. It is concluded that focus must shift to address the gap between having available drugs and being able to access and afford them. F.J.

[Orphan drugs : New opportunities for the treatment of rare diseases]. / Orphan Drugs : Neue Möglichkeiten zur Behandlung seltener Erkrankungen.

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.

Do we need authorized orphan drugs when compounded medications are available?

WHAT IS KNOWN AND OBJECTIVE: Orphan drugs are used to diagnose, prevent or treat a rare disease. This Commentary aims to present a number of case studies questioning the need for designating compounded medications with a long history of effective use, which is well-supported by published clinical evidence. COMMENT: Prior to the market introduction of orphan drugs, medication compounding was done in our hospital pharmacy for several rare diseases. Examples include amifampridine for the treatment of Lambert-Eaton myasthenic syndrome (Firdapse(®)), ibuprofen for the treatment of neonatal patent ductus arteriosus (Pedea(®)) and zinc acetate for the treatment of Wilson's disease (Wilzin(®)). Several 'non-orphan' pharmaceutical products, used off-label for the treatment of rare diseases, that became orphan medicinal products include Hydrea(®) for the treatment of sickle-cell syndrome (Siklos(®)) and Viagra(®) for the treatment of pulmonary arterial hypertension (Revatio(®)). WHAT IS NEW AND CONCLUSION: In our opinion, as indicated by our examples, a better balance should be struck between the development of orphan drugs along the recently established regulatory pathways and the pragmatic use of pharmacy-compounded products and evidence-based off-label use of already available commercial products. Societal needs would be best met by focusing orphan drug development on rare diseases for which there is a high unmet medical need.

Impact of biomarker usage on oncology drug development.

WHAT IS KNOWN AND OBJECTIVE: The increasing cost of drug research and development and the decreasing number of new drugs being launched are serious issues for pharmaceutical companies. Biomarkers for predicting drug effectiveness are regarded as useful tools for combating these trends. However, the extent to which these biomarkers actually help in improving drug development is unclear. Here, we investigated the efficiency of biomarker usage in oncology drug development by focusing on stratification markers. METHODS: Anti-tumour agents for which clinical studies were initiated between 1998 and 2009 were identified using commercially available data sources, and clinical trials registered in ClinicalTrials.gov were examined to identify the use of stratification marker. Phase transition probability for each clinical phase was calculated and analysed along with various other factors that may affect the efficiency of the development process. RESULTS AND DISCUSSION: Of 908 anti-tumour agents identified, 121 (13·3%) utilized stratification markers in their clinical studies. Phase I, II and III transition probabilities for all agents were 76·4%, 50·8% and 58·5%, respectively. Corresponding Phase I, II and III transition probabilities of agents developed with stratification markers of 90·4%, 69·0% and 85·0%, respectively, were significantly higher than those for agents without stratification markers. Orphan designation positively affected phase transition probabilities of agents without stratification markers in all phases, while it did not affect transition probabilities of agents with stratification markers, except for Phase II. This shows that stratification markers help improve the probability of success in the development of agents without orphan designation. WHAT IS NEW AND CONCLUSION: Stratification markers contribute to improving the efficiency of development of anti-cancer drugs. The majority of non-orphan drugs are still being developed without stratification markers. Finding reliable stratification markers for all drugs should improve the success rates in drug development.

Orphan drug development.

Commercial treatment for a lysosomal storage disorder (LSD; i.e., Gaucher disease) became available in 1991 as a consequence of collaborative efforts between the National Institutes of Health and a biotechnology company, Genzyme Corporation, fostered by the Orphan Drug Act. (ODA, 1983) Other therapies were subsequently introduced for other LSDs (e.g., for Fabry disease) through ODA-driven incentives, as combined projects between academia and industry, facilitated by the Bayh-Dole Act (1980). Today, several enzyme therapies are available and other treatment options are anticipated, including small molecular drugs which inhibit substrate synthesis or act as pharmacologic chaperones. Disease-specific therapies has modified disease course to varying extents, and on-going data collection through registry/observational programs are in place to characterize both long-term safety and efficacy. Aspects of disease that remain challenging include those resulting from bone and brain involvement, which may necessitate novel therapeutic strategies. Issues related to high cost of therapy and access also remain to be addressed.

Multidisciplinary approach to R&D in vitiligo, a neglected skin disease.

A global interest in therapies for neglected diseases is rising, but traditional biopharma research and development (R&D) process is prohibitively expensive to justify cost of their development. Vitiligo is a multifactorial orphan disease that affects at minimum 35 million people worldwide, yet no therapeutic solutions exist. The present authors describe a budget-minded pursuit of the new therapy development for vitiligo, which includes a multidiscipline collaboration and effective bridging between academic research, biobanking, and bioinformatics. The present authors anticipate that the present authors' "theoretically induced and empirically guided" discovery process will enable development of more leads, with a much greater probability of success and under tighter budgets compared with those of the biopharma company. Ultimately, the multidisciplinary approach described below facilitates the collaborative development of personalized treatments for different patient subpopulations in vitiligo and other neglected diseases.

Availability, accessibility and delivery to patients of the 28 orphan medicines approved by the European Medicine Agency for hereditary metabolic diseases in the MetabERN network.

BACKGROUND: The European Medicine Agency granted marketing approval to 164 orphan medicinal products for rare diseases, among which 28 products intended for the treatment of hereditary metabolic diseases. Taking advantage of its privileged connection with 69 healthcare centres of excellence in this field, MetabERN, the European Reference Network for hereditary metabolic diseases, performed a survey asking health care providers from 18 European countries whether these products are available on the market, reimbursed and therefore accessible for prescription, and actually delivered in their centre. RESULTS: Responses received from 52 centres (75%) concerned the design of treatment plans, the access to marketed products, and the barriers to delivery. Treatment options are always discussed with patients, who are often involved in their treatment plan. Most products (26/28) are available in most countries (15/18). Among the 15 broadly accessible products (88.5% of the centres), 9 are delivered to most patients (mean 70.1%), and the others to only few (16.5%). Among the 10 less accessible products (40.2% of the centres), 6 are delivered to many patients (66.7%), and 4 are rarely used (6.3%). Information was missing for 3 products. Delay between prescription and delivery is on average one month. Beside the lack of availability or accessibility, the most frequent reasons for not prescribing a treatment are patients' clinical status, characteristic, and personal choice. CONCLUSIONS: Data collected from health care providers in the MetabERN network indicate that two-third of the orphan medicines approved by EMA for the treatment of hereditary metabolic diseases are accessible to treating patients, although often less than one-half of the patients with the relevant conditions actually received the approved product to treat their disease. Thus, in spite of the remarkable achievement of many products, patients concerned by EMA-approved orphan medicinal products have persistent unmet needs, which deserve consideration. The enormous investments made by the companies to develop products, and the high financial burden for the Member States to purchase these products emphasize the importance of a scrupulous appreciation of treatment value involving all stakeholders at early stage of development, before marketing authorization, and during follow up.

Feasibility Study for Bedside Production of Recombinant Human Acid α-Glucosidase: Technical and Financial Considerations.

OBJECTIVE: The high cost of orphan drugs limits their access by many patients, especially in low- and middle-income countries. Many orphan drugs are off-patent without alternative generic or biosimilar versions available. Production of these drugs at the point-of-care, when feasible, could be a cost-effective alternative. METHODS: The financial feasibility of this approach was estimated by setting up a small-scale production of recombinant human acid alpha-glucosidase (rhGAA). The commercial version of rhGAA is Myozyme™, and Lumizyme™ in the United States, which is used to treat Pompe disease. The rhGAA was produced in CHO-K1 mammalian cells and purified using multiple purification steps to obtain a protein profile comparable to Myozyme™. RESULTS: The established small-scale production of rhGAA was used to obtain a realistic cost estimation for the magistral production of this biological drug. The treatment cost of rhGAA using bedside production was estimated at $3,484/gram, which is 71% lower than the commercial price of Myozyme ™. CONCLUSION: This study shows that bedside production might be a cost-effective approach to increase the access of patients to particular life-saving drugs.

Implementing reflective multicriteria decision analysis (MCDA) to assess orphan drugs value in the Catalan Health Service (CatSalut).

BACKGROUND: Orphan medicines show some characteristics that hinder the evaluation of their clinical added value. The often low level of evidence available for orphan drugs, together with a high budget impact and an incremental cost-effectiveness ratio many times higher than drugs used for non-orphan diseases, represent challenges in their appraisal and effective access to clinical use. In order to explore how to handle these hurdles, the Catalan Health Service (CatSalut) began an initiative on a multidimensional assessment of drugs value during the appraisal process. Reflective multicriteria decision analysis (MCDA) using analytical methods was chosen, since it may help to standardise and contextualize all the relevant data related with the drug that could contribute to a decision. The aim of the study was to determine whether the implementation of reflective MCDA methodology could support the decision-making process about orphan medicines in the context of CatSalut. METHODS: The assessment and decision-making process for orphan drugs in the Programa d'Harmonització Farmacoterapeutica (PHF) of CatSalut was prioritized to test the implementation of the reflective MCDA both a qualitative and quantitatively. A staged approach was used with the following main steps: selection and structuration of quantitative criteria (Core Model) and qualitative criteria (Contextual Tool), framework scoring and assessment of three orphan drug case studies. This proof-of-concept would grant a continued refinement of the methodology and, if and when validated, its potential integration to other therapeutic areas of the PHF. RESULTS: The final framework was composed by 10 quantitative criteria (Core Model) and 4 qualitative criteria (Contextual Tool) according to the PHF goals being the most important criteria "disease severity", "unmet need", "comparative effectiveness" and "comparative safety /tolerability". The matrix developed for the case studies served as a guide for the selection of the essential information that the decision-makers were expected to include in a framework. The reflective discussion was considered the most relevant phase of the approach to support inputs for health decision-making processes reflecting both drug value and place in therapy. CONCLUSIONS: The study showed that reflective MCDA methodology could be implemented to complement the decision-making process in CatSalut, as an aid to determine the clinical added value for orphan medicines. MCDA provided transparency and a structured discussion during the committee meetings, thus increasing transparency and predictability of the relevant items supporting the agreements adopted on orphan drugs access.

A human-on-a-chip approach to tackling rare diseases.

Drug development for rare diseases, classified as diseases with a prevalence of < 200 000 patients, is limited by the high cost of research and low target population. Owing to a lack of representative disease models, research has been challenging for orphan drugs. Human-on-a-chip (HoaC) technology, which models human tissues in interconnected in vitro microfluidic devices, has the potential to lower the cost of preclinical studies and increase the rate of drug approval by introducing human phenotypic models early in the drug discovery process. Advances in HoaC technology can drive a new approach to rare disease research and orphan drug development.

International experiences in multicriteria decision analysis (MCDA) for evaluating orphan drugs: a scoping review.

Introduction: Orphan diseases are low-prevalence conditions with chronically debilitating or life-threatening consequences. Their treatments are generally called orphan drugs (OD). Health-technology assessment processes have traditionally considered cost-effectiveness analysis (CEA), when making reimbursement and pricing decisions for health-care plans. Valuing OD with standard CEA raises important issues due to uncertain evidence, inability to meet cost-effectiveness thresholds for reimbursement and high budget impact, among others. Multi-criteria decision analysis (MCDA) allows to overcome these issues and improve the technical and ethical quality of decisions regarding prioritization, coverage, and reimbursement of OD. Areas covered: A scoping review was conducted in order to characterize MCDA frameworks for assessing OD and implementation experiences. We reviewed electronic databases (Medline, Embase, Cochrane Library, EBSCO, CINAHL, EconLit, Web of Science, LILACS, Google Scholar) key journals (Orphanet Journal of Rare Diseases and Value in Health) and organization repositories. Expert opinion: The theoretical framework for MCDA considers areas related to characteristics of orphan diseases and their technologies' clinical and economic impact. Participation processes are critical in incorporating societal values in weighting different dimensions and constructing decision rules. Local implementation pilots considering different stakeholders are necessary in order to pinpoint specific barriers and opportunities.

Factors associated with positive and negative recommendations for cancer and non-cancer drugs for rare diseases in Canada.

BACKGROUND: In Canada, reimbursement recommendations on drugs for common and rare diseases are overseen by the Canadian Agency for Drugs and Technologies in Health (CADTH) and made through the pan-Canadian Oncology Drug Review (pCODR) and the Common Drug Review (CDR). While the agency specifies information requirements for the review of drug submissions, how that information is used by each process to formulate final reimbursement recommendations, particularly on drugs for rare diseases (DRDs) in which per patient treatment costs are often high, is unclear. The purpose of this study was to determine which factors contribute to recommendation type for DRDs. METHODS: Information was extracted from CDR and pCODR recommendations on drugs for diseases with a prevalence < 1 in 2000 from January 2012 to April 2018. Data were tabulated and multiple logistic regression was applied to explore the association between recommendation type and the following factors: condition/review process (cancer vs non-cancer), year, prevalence, clinical effectiveness (improvements in surrogate, clinical and patient reported outcomes), safety, quality of evidence (availability of comparative data, consistency between population in trial and indication, and bias), clinical need, treatment cost, and incremental cost-effective ratio (ICER). Two-way interactions were also explored. RESULTS: A total of 103 recommendations were included. Eleven were resubmissions, all of which received a positive recommendation. Among new submissions (n = 92), DRDs that were safe or offered improvements in clinical or patient reported outcomes were more likely to receive positive reimbursement recommendations. No associations between recommendation type and daily treatment cost, cost-effectiveness, or condition (cancer or non-cancer) were found. CONCLUSIONS: Clinical effectiveness, as opposed to economic considerations or whether the drug is indicated for cancer or non-cancer, determine the type of reimbursement recommendation.