ERN BOND: The key European network leveraging diagnosis, research, and treatment for rare bone conditions.

There is no universally accepted definition for rare diseases: in Europe a disease is considered to be rare when affecting fewer than 1 in 2000 people. European Reference Networks (ERNs) have been the concrete response to address the unmet needs of rare disease patients and many pan-European issues in the field, reducing inequities, and significantly increasing accessibility to high-quality healthcare across Europe. ERNs are virtual networks, involving centres and patient representatives with the general scope to facilitate discussion on complex cases requiring highly specialised competences and trained expertise. ERN BOND - the European Reference Network on rare BONe Diseases - is one of these 24 approved networks with the specific ongoing mission to implement measures facilitating multidisciplinary, holistic, continuous, patient-centred, and participative care provision to patients, and supporting them in the full realisation of their fundamental human rights. ERN BOND includes in 2023 a total of 53 centres of expertise from 20 European countries. Its governing structure installed in March 2017 includes decision-making, operative and consultative committees, which comprise experts in the field and patient representatives ensuring patient's voice and perspectives are taken into account. Over the years, ERN BOND has worked hard to achieve its mission and valuably contribute to the advancement of diagnosis, management, treatment, and research in rare diseases. The network activities are mainly related to (i) the provision of care which collectively involves averagely 2800 patients diagnosed per year, (ii) the development of education for and training of the healthcare personnel consisting until now in the realisation of 7 thematic workshops and 19 webinars, (iii) the dissemination and exchange and spread of knowledge via network's website (https://ernbond.eu/), social media channels, and newsletters, (iv) the management of related data through a disease registry currently mapping over 2300 cases and recording over 600 reported cases, and (v) the enhancement of research which now include two clinical trials endorsed by the network. ERN BOND represents therefore an unprecedented move to improve the healthcare management of patients suffering from rare bone diseases through European collaborations. This network, through the support from the European Health Programme, will continue to pursue its efforts to achieve its goals, always maintaining the patients and their families at the centre of healthcare services.

[Exploration of clinical pathway-oriented optimal management diagnosis and treatment model for rare diseases].

This study takes Cushing's syndrome, a rare disease, as a model, and adopts the path of "Plan, Do, Check, Action" (PDCA) to explore new methods to optimize the clinical path, can improve the quality and efficiency of diagnosis and treatment of rare diseases. After sorting out the problems existing in the previous diagnosis and treatment mode, our team optimizes the path in various ways and establishes a standard operation procedure (SOP) for the new path. In the evaluation of the optimized mode, 55 patients with Cushing's syndrome were admitted to the Department of Endocrinology, Peking Union Medical College Hospital, including 19 males and 36 females, aged (41.8±14.4) years (6-68 years). The pathway group (28 cases) and the control group (27 cases) were divided according to whether they were included in the new path management at the time of admission, and the effect of path optimization was assessed in terms of time, efficacy, safety and cost. The results showed that compared with the control group, the pathway group had a shorter time of hospitalization in the Department of Endocrinology and critical tests, such as blood cortisol rhythm, low-dose dexamethasone inhibition test, and bilateral inferior petrosal sinus sampling (all P<0.05). There was no significant differences in the decrease of total cortisol after operation, the incidence of postoperative complications, and hospitalization expenses (all P>0.05). The optimized path improves the medical efficiency while ensuring medical quality, safety and no increase in cost. This study proposes PDCA path optimization for complex diseases and establishes SOP process, which provides experience in management optimization for the patient-centered and clinical path-oriented diagnosis and treatment mode of rare diseases.

Designing rare disease care pathways in the Republic of Ireland: a co-operative model.

BACKGROUND: Rare diseases (RDs) are often complex, serious, chronic and multi-systemic conditions, associated with physical, sensory and intellectual disability. Patients require follow-up management from multiple medical specialists and health and social care professionals involving a high level of integrated care, service coordination and specified care pathways. METHODS AND OBJECTIVES: This pilot study aimed to explore the best approach for developing national RD care pathways in the Irish healthcare system in the context of a lack of agreed methodology. Irish clinical specialists and patient/lived experience experts were asked to map existing practice against evidence-based clinical practice guidelines (CPGs) and best practice recommendations from the European Reference Networks (ERNs) to develop optimal care pathways. The study focused on the more prevalent, multisystemic rare conditions that require multidisciplinary care, services, supports and therapeutic interventions. RESULTS: 29 rare conditions were selected across 18 ERNs, for care pathway development. Multidisciplinary input from multiple specialisms was relevant for all pathways. A high level of engagement was experienced from clinical leads and patient organisations. CPGs were identified for 26 of the conditions. Nurse specialist, Psychology, Medical Social Work and Database Manager roles were deemed essential for all care pathways. Access to the therapeutic Health Service Professionals: Physiotherapy, Occupational Therapy, and Speech and Language Therapy were seen as key requirements for holistic care. Genetic counselling was highlighted as a core discipline in 27 pathways demonstrating the importance of access to Clinical Genetics services for many people with RDs. CONCLUSIONS: This study proposes a methodology for Irish RD care pathway development, in collaboration with patient/service user advocates. Common RD patient needs and health care professional interventions across all pathways were identified. Key RD stakeholders have endorsed this national care pathway initiative. Future research focused on the implementation of such care pathways is a priority.

mEDUrare: Supporting Integrated Care for Rare Diseases by Better Connecting Health and Education Through Policy.

Rare diseases affect an estimated 6-10% of the Australian population, a prevalence similar to that seen in other regions worldwide. These multi-system conditions are often severely debilitating and affect multiple domains of a person's life. A salient necessity for effective care provision thus, is holistic care, achieved by appropriate and continual multi-disciplinary and cross-sectoral collaboration. Synonymous with this priority for collaborative care, is the need for increased partnerships between the health and education sectors. This partnership has the potential to benefit people with rare disease of all educational ages, but in particular, school-aged children and young adults. More than 70% of rare diseases affect children, and this population often experiences difficulties with overall well-being and functioning, including impaired school performance and confounding mental and social comorbidities. Ensuring adequate schooling needs and experiences along with provision of adequate medical care, is crucial in ensuring overall well-being for this population. For this, effective partnerships between the health and education sectors are paramount. This article highlights fundamental elements of health and education priorities, ingrained in current strategic documents, to build a policy foundation that informs and supports increased inter-sectoral partnerships between health and education services. Shared priorities identified in both sectors' guidelines, co-developed with those with lived experience of rare diseases, build a strong policy base for future advocative initiatives to mold better integration between the sectors, a partnership which is vital to improving the overall quality of life, experiences and journeys of people living with rare disease.

Clinical trials in skeletal dysplasia: a paradigm for treating rare diseases.

BACKGROUND: Genetic skeletal dysplasia conditions (GSDs) account for 5% of all birth defects. Until recently, targeted treatments were only available for select few conditions; 1 however, opportunities arising from developments in molecular diagnostic technologies are now leading to unparalleled therapeutic advances. This review explores current GSD clinical trials, their challenges and the hopes for the future. SOURCES OF DATA: A systematic literature search of relevant original articles, reviews and meta-analyses restricted to English was conducted using PubMed up to February 2020 regarding emerging GSD therapies. AREAS OF AGREEMENT: We discuss current clinical trials for in achondroplasia, osteopetrosis, osteogenesis imperfecta, hypophosphataemic rickets, hypophosphatasia and fibrous ossificans progressiva. AREAS OF CONTROVERSY: We explore challenges in GSD drug development from clinician input, cost-effectiveness and evidenced-based practice. GROWING POINTS: We explore opportunities brought by earlier diagnosis, its treatment impact and the challenges of gene editing. AREAS TIMELY FOR DEVELOPING RESEARCH: We horizon scan for future clinical trials.

Glassy cell carcinoma of the uterine cervix: 20-year experience from a comprehensive cancer center.

PURPOSE: Glassy cell carcinoma (GCC) of the uterine cervix is a rare entity. This study aims at describing the clinical characteristics and outcomes of cervical GCC patients treated in a comprehensive cancer center. MATERIAL AND METHODS: We retrospectively reported patients and tumors characteristics, therapeutic management, overall survival (OS), progression-free progression (PFS), relapse rates, and toxicities. RESULTS: Between 1994 and 2014, 55 patients were treated with curative intent. The median age at diagnosis was 41 years (range, 20-68). Among 22 patients with early stage tumors (IA2-IB1-IIA1), 17 had preoperative brachytherapy, followed by radical hysterectomy. Among 33 patients with locally advanced disease (≥IB2), 32 underwent chemoradiation±brachytherapy boost. After a median follow-up of 5.4 years (range, 0.15-21.7 years), 18/55 (33%) patients experienced tumor relapse. Local recurrence occurred in 2/22 (9%) patients with early disease (treated with upfront surgery) and in 3/32 (9%) patients with locally advanced disease. Most frequent relapses were distant, occurring in a total of 11/55 patients (20%). PFS rates at 5-year were 86.4% (95% CI: 63.4-95.4) for early stage versus 75.9% (95% CI: 55.2-89.2) for locally advanced stages, respectively (P=0.18). CONCLUSION: Large cohort data are warranted to guide the optimal management of GCC. From this retrospective analysis, a multimodal approach yielded to good disease control in early stages tumors. Given the high-risk of distant failure, consideration should be given to adjuvant chemotherapy in locally advanced disease.

Successful use of hyperbaric oxygen therapy for limb salvage of acute limb ischemia as a complication of acute carbon monoxide poisoning.

Acute limb ischemia (ALI) as a complication of acute carbon monoxide (CO) poisoning is rare. Several reports have utilized hyperbaric oxygen therapy (HBO2) as an adjunctive therapy for peripheral arterial diseases. However, no study has yet described the use of HBO2 for ALI precipitated by CO poisoning. Herein we report successful limb salvage achieved with adjunctive HBO2 and conventional therapies in a patient with CO-induced ALI. A 69-year-old man was admitted with acute CO poisoning; ALI of both lower extremities occurred on hospitalization day 3. Pre-existing risk factors for ALI other than CO were not definite. After conventional treatments including catheter-directed thrombolysis and endovascular thrombectomy, the right-side lesion remained and a left-side lesion was newly developed. In addition to prior therapies, 47 sessions of serial HBO2 were administered as adjunctive therapy, resulting in limb salvage. Acute CO poisoning can cause ALI as a rare complication. HBO2 may be utilized as an adjunctive treatment in ALI.

New problems of a new health system: the creation of a national public policy of rare diseases care in Brazil (1990s-2010s). / Nuevos problemas de un nuevo sistema de salud: la creación de una política pública nacional de atención de enfermedades raras en Brasil (1990-2014).

This study discusses actors and institution movements leading to the disclosure in 2014 of Resolution 199 by the Brazilian Ministry of Health, which establishes the National Policy for the Comprehensive Care of Persons with Rare Diseases. Taking as sources the mainstream newspapers, drafts law, and secondary literature on the subject, we begin our analysis in the early 1990s when the first patient associations were created in Brazil - mainly for claiming more funds for research on genetic diseases - and arrive at the late 2010s when negotiations for a national policy are taking place in the National Congress. Resolution 199 is part of an ongoing process and the path towards its disclosure and the complications that followed have given us elements to discuss contemporary aspects of the Brazilian public health. Based on the references of the history of the present time and the social studies of science, we argue that two aspects have been fundamental to creating a national policy: framing different illnesses within the terminology "rare diseases" and the construction of a public perception about the right of health which is guaranteed by the 1988 Brazilian Constitution.

En este trabajo se analizan los movimientos de actores e instituciones que llevaron a la promulgación, en 2014, de la Resolución 199 del Ministerio de Salud de Brasil, que establece la Política Nacional de Atención Integral a las Personas con Enfermedades Raras. Tomando como fuentes los principales periódicos, proyectos de ley y bibliografía secundaria sobre el tema, comenzamos nuestro análisis a principios de la década de 1990 con la creación de las primeras asociaciones de pacientes en Brasil, para reclamar fundamentalmente más fondos para la investigación de enfermedades genéticas, y llegamos a fines de la década de 2010 con las negociaciones para una política nacional. La Resolución 199 es parte de un proceso en curso, en el que el camino hacia la promulgación y las complicaciones posteriores nos dan elementos para discutir aspectos actuales de la salud pública brasileña. Sobre la base de la historia del tiempo presente y los estudios sociales de la ciencia, argumentamos que hay dos aspectos que han sido fundamentales para crear una política nacional: enmarcar diferentes enfermedades en la terminología "enfermedades raras" y la construcción de una percepción pública sobre el derecho a la salud, que se garantiza en la Constitución brasileña de 1988.

Nuevos problemas de un nuevo sistema de salud: la creación de una política pública nacional de atención de enfermedades raras en Brasil (1990-2014) / New problems of a new health system: the creation of a national public policy of rare diseases care in Brazil (1990s-2010s)

RESUMEN En este trabajo se analizan los movimientos de actores e instituciones que llevaron a la promulgación, en 2014, de la Resolución 199 del Ministerio de Salud de Brasil, que establece la Política Nacional de Atención Integral a las Personas con Enfermedades Raras. Tomando como fuentes los principales periódicos, proyectos de ley y bibliografía secundaria sobre el tema, comenzamos nuestro análisis a principios de la década de 1990 con la creación de las primeras asociaciones de pacientes en Brasil, para reclamar fundamentalmente más fondos para la investigación de enfermedades genéticas, y llegamos a fines de la década de 2010 con las negociaciones para una política nacional. La Resolución 199 es parte de un proceso en curso, en el que el camino hacia la promulgación y las complicaciones posteriores nos dan elementos para discutir aspectos actuales de la salud pública brasileña. Sobre la base de la historia del tiempo presente y los estudios sociales de la ciencia, argumentamos que hay dos aspectos que han sido fundamentales para crear una política nacional: enmarcar diferentes enfermedades en la terminología "enfermedades raras" y la construcción de una percepción pública sobre el derecho a la salud, que se garantiza en la Constitución brasileña de 1988.

ABSTRACT This study discusses actors and institution movements leading to the disclosure in 2014 of Resolution 199 by the Brazilian Ministry of Health, which establishes the National Policy for the Comprehensive Care of Persons with Rare Diseases. Taking as sources the mainstream newspapers, drafts law, and secondary literature on the subject, we begin our analysis in the early 1990s when the first patient associations were created in Brazil - mainly for claiming more funds for research on genetic diseases - and arrive at the late 2010s when negotiations for a national policy are taking place in the National Congress. Resolution 199 is part of an ongoing process and the path towards its disclosure and the complications that followed have given us elements to discuss contemporary aspects of the Brazilian public health. Based on the references of the history of the present time and the social studies of science, we argue that two aspects have been fundamental to creating a national policy: framing different illnesses within the terminology "rare diseases" and the construction of a public perception about the right of health which is guaranteed by the 1988 Brazilian Constitution.

Integrated care for healthcare sustainability for patients living with rare diseases.

The increasingly complex and multidimensional care request, combined with the presence of increasingly aware and demanding patients, accentuates the need for new strategies to preserve health systems economic sustainability. Therefore, integration mechanisms reveal an essential condition for ensuring continuity of care. The paper reviews the main literature available on the integration of heal services and relates it to rare diseases. The literature identifies several system levers for the effective design and implementation of integrated care frameworks, namely: political support and commitment, governance, stakeholder engagement, organisational change, leadership, collaboration and trust, workforce education and training, patient empowerment, financing and incentives, ICT infrastructure and solutions, monitoring and evaluation system.

Patient empowerment of people living with rare diseases. Its contribution to sustainable and resilient healthcare systems.

The notion of empowerment is linked to patients' everyday life and is the base allowing for the patient engagement through which individuals and communities are able to express their needs, are involved in decision-making, take action to meet those needs. In the field of rare diseases, empowerment strategies have greater value due to low prevalence, lack of expertise, poor quality of life. Avenues to patient empowerment are: health literacy and capacity-building; shared decision-making; support to self-management. Patient empowerment is recognised as key enabler in creating sustainability as addressing challenges faced by modern healthcare systems in terms of effectiveness, access and resilience. It is recommended to develop a comprehensive EU roadmap on patient empowerment including specific recommendations, taking stock of good practices. This holistic approach should lead to a society where all actors are fulfilled human beings and unmet needs are addressed in compliance with fundamental human rights.

[Importance of psychosomatic medicine for people with rare diseases]. / Bedeutung der psychosomatischen Medizin für Menschen mit seltenen Erkrankungen.

People with rare diseases have a very high rate of mental and social stress. This results in specific tasks and problems in the psychosomatic care of patients. On the one hand, the physical and/or psychological symptoms of an undetected rare organic disease can be misdiagnosed as a psychosomatic disease, and the affected persons possibly receive psychotherapy that is not causally effective. On the other hand, mental diseases that require treatment can arise as a result of the effects of a rare disease. These should be diagnosed as such and treated with psychotherapy. If, in individual cases, both symptoms of a rare disease and symptoms of a psychosomatic disorder in the sense of comorbidity are present, neither one nor the other diagnosis should lead to a hasty termination of diagnostic efforts. Otherwise, misalignments can easily occur and the further diagnostic and therapeutic process can be permanently disturbed. Interdisciplinary team care interventions should therefore be developed further.

[Treatment networks and associations of patients with rare diseases]. / Redes de tratamento e as associações de pacientes com doenças raras.

Patients' associations are an example of biosocial groups, since their formation is motivated by common biological characteristics, such as rare diseases, and they are sometimes included in social movements in health. Even though the National Policy on Comprehensive Care for Persons with Rare Diseases was enacted in 2014, patients still struggle to ensure access to and treatment by the Unified Health System. The way in which associations of patients with rare diseases gain access to treatment via social networks, is investigated. This research is part of a study about the use of social media by associations of patients with rare diseases, which employs netnography - ethnography applied to the web - as the data-gathering method. Data sources were pages of the associations on Facebook in Brazil. It was seen that the activities of the associations are multi-faceted, ranging from patient and family guidance about treatment and quality of life, to active participation in the elaboration and implementation of public policies. The discourses suggest that the focus of patients' associations is, in the majority of cases, the access to drugs rather than the effective enactment of the national policy geared towards rare diseases.

As associações de pacientes são um exemplo de grupos biossociais, já que sua constituição é motivada por questões biológicas comuns, tais como as doenças raras, e estão, por vezes, inscritas no movimento social em saúde. Apesar da Política Nacional de Atenção Integral às Pessoas com Doenças Raras ter sido promulgada em 2014, os pacientes ainda têm dificuldade em garantir acesso a tratamento pelo Sistema Único de Saúde. Investigamos como as associações de pacientes com doenças raras tecem, através das redes sociais virtuais, o acesso a tratamento. Esta pesquisa é parte de um estudo sobre o uso das mídias sociais pelas associações de pacientes com doenças raras, e emprega como método a netnografia. As fontes da pesquisa foram páginas de associações de pacientes com doenças raras no Brasil presentes no Facebook. Observamos que a atuação das associações de pacientes é plural, indo desde a orientação de pacientes e familiares sobre questões relacionadas a tratamento e qualidade de vida, até a participação ativa na elaboração e implementação de políticas públicas. Os discursos sugerem que o foco destas associações é, na maior parte dos casos, o acesso a medicamentos, em detrimento da implantação efetiva da Política Nacional de Atenção Integral às Pessoas com Doenças Raras.

The role of the chronic care model in promoting the management of the patient with rare liver disease.

INTRODUCTION: The chronic care model (CCM) provides a holistic approach for managing chronic illnesses. Patients with rare liver diseases (RLD) have complex needs, impaired quality of life and often life-threatening complications. Most RLD meet the criteria for a long-term chronic condition and should be viewed through the prism of CCM. We aimed to ascertain whether the CCM has been considered for the frequently-encountered RLD. METHODS: MEDLINE®/PubMed®/Cochrane/EMBASE were searched to identify publications relating to the use of the CCM for the management of six RLD. We identified 33 articles eligible for inclusion. RESULTS: Six, eleven, one, thirteen, two and zero studies, discussed individual components of the CCM for autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), primary sclerosing cirrhosis (PSC), Wilsons disease (WD), alpha-1 antitrypsin deficiency (A1AD) and lysosomal acid lipase deficiency (LALd) respectively. We have not identified studies using the full CCM for any of the aforementioned RLD. DISCUSSION: Unlike in common chronic conditions e.g. diabetes, there has been limited consideration of the use of CCM (or its components) for the management of RLD. This may reflect a reluctance of the clinical community to view these diseases as chronic or lack of healthcare policy investment in rare diseases in general.

Peritoneal Carcinomatosis of Rare Ovarian Origin Treated by Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy: A Multi-Institutional Cohort from PSOGI and BIG-RENAPE.

PURPOSE: Ovarian cancer is the most common deadly cancer of gynecologic origin. Patients often are diagnosed at advanced stage with peritoneal metastasis. There are many rare histologies of ovarian cancer; some have outcomes worse than serous ovarian cancer. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) can be considered for patients with recurrence. This study was designed to assess the impact of CRS and HIPEC on survival of patient with peritoneal metastasis from rare ovarian malignancy. METHODS: A prospective, multicentric, international database was retrospectively searched to identify all patients with rare ovarian tumor (mucinous, clear cells, endometrioid, small cell hypercalcemic, and other) and peritoneal metastasis who underwent CRS and HIPEC through the Peritoneal Surface Oncology Group International (PSOGI) and BIG-RENAPE working group. The postoperative complications, long-term results, and principal prognostic factors were analyzed. RESULTS: The analysis included 210 patients with a median follow-up of 43.5 months. Median overall survival (OS) was 69.3 months, and the 5-year OS was 57.7%. For mucinous tumors, median OS and DFS were not reached at 5 years. For granulosa tumors, median overall survival was not reached at 5 years, and median DFS was 34.6 months. Teratoma or germinal tumor showed median overall survival and DFS that were not reached at 5 years. Differences in OS were not statistically significant between histologies (p = 0.383), whereas differences in DFS were (p < 0.001). CONCLUSIONS: CRS and HIPEC may increases long-term survival in selected patients with peritoneal metastasis from rare ovarian tumors especially in mucinous, granulosa, or teratoma histological subtypes.

Engagement of Canadian Patients with Rare Diseases and Their Families in the Lifecycle of Therapy: A Qualitative Study.

INTRODUCTION: Patient involvement is increasingly recognized as critical to the development, introduction and use (i.e. the lifecycle) of new and effective therapies, particularly those for rare diseases, where natural histories and the impact on patients and families are less well-understood than for common diseases. However, little is known about how patients and families would like to be involved during the lifecycle. OBJECTIVE: The aim of this study was to explore ways in which Canadian patients with rare diseases and their families would like to be involved in the lifecycle of therapies and identify their priorities for involvement. METHODS: Patients with rare diseases and their families were recruited to participate in two deliberative sessions, during which concepts related to decision-making uncertainty and the technology lifecycle were introduced before eliciting input around ways in which they could be involved. This was followed by a webinar, which was used to further identify opportunities for involvement. The data were then analyzed qualitatively using eclectic coding. RESULTS: Patients and families identified opportunities that fell into three goals: (1) incorporation of their 'lived experience' in coverage decision making (i.e. decisions by governments on funding new therapies); (2) improved care for patients; and (3) greater awareness of rare diseases, with the first being a priority. CONCLUSIONS: Opportunities for patients and families to contribute their 'lived experience' are needed throughout the orphan drug lifecycle, but the ideal mechanisms for providing this input have yet to be determined.

A Review on Pityriasis Rubra Pilaris.

Pityriasis rubra pilaris (PRP) is an idiopathic, papulosquamous inflammatory dermatosis. It is characterized by hyperkeratotic follicular papules coalescing into orange-red scaly plaques, islands of sparing, and palmoplantar keratoderma. PRP can be subdivided into six clinical subtypes according to Griffiths' classification, based on age of onset, disease extent, prognosis, and other associated features. The sixth subtype of PRP occurs in individuals affected by HIV infection, and retroviral screening in all de novo cases of PRP is advised. Other reported associations include various infections, autoimmunity, drugs, and malignancies, although the true significance of these is still unclear. The genetic basis for familial cases, most commonly categorized under the fifth subtype, has been mapped to gain of function mutations in the caspase recruitment domain family, member 14 (CARD14) gene. Treatment of PRP remains a challenge to this day due to a paucity of high-quality evidence. Therapeutic regimens have been guided mostly by case reports and case series, with the mainstay of treatment being oral retinoids. Recently, biologics have emerged as a promising treatment for PRP. We present a review of the clinicopathologic features, pathogenesis, associated disorders, and treatment of PRP, with an emphasis and critical appraisal of the existing literature on the latter.

Challenges of developing and conducting clinical trials in rare disorders.

Rare disease drug development is a rapidly expanding field. Clinical researchers in rare diseases face many challenges when conducting trials in small populations. Disease natural history is often poorly understood and the ability to detect clinically meaningful outcomes requires understanding of their rate of occurrence and variability, both of which contribute to difficulties in powering a study. Standard trial designs are not optimized to obtain adequate safety and efficacy data from small numbers of patients, so alternative designs (enrichment, crossover, adaptive, N-of 1) need to be considered. The affected patients can be hard to identify, especially early in the course of their disease, are generally geographically dispersed, and are often children. Trials are frequently conducted on an international scale and may be subject to complex or multiple regulatory agency oversights and may be affected by local customs, cultures, and practices. A basic understanding of the FDA programs supporting development of drugs for rare diseases is provided by this review and the role of early consultation with the FDA is emphasized. Of recent FDA New Molecular Entities (NME) approvals, 41% (17 approvals) in 2014, 47% (21 approvals) in 2015, and 41% (9 approvals) in 2016 were for rare disease indications. Through effective interactions and collaborations with physicians, institutions, and patient groups, sponsors have been successful in bringing new treatments to market for individuals affected by rare diseases. Challenges to drug development have been overcome through the focused efforts of patients/families, non-profit patient advocacy groups, drug developers, and regulatory authorities.