Development of a Conceptual Model for the Patient Experience of Immunoglobulin A Nephropathy (IgAN): A Qualitative Literature Review.

INTRODUCTION: Immunoglobulin A nephropathy (IgAN) is a kidney disorder that can lead to progressive kidney disease. Currently, there lacks a comprehensive overview of the symptoms and impacts experienced by those living with IgAN that would help inform the selection or development of fit-for-purpose clinical outcome assessments (COA) to be used in clinical trials. The aim of this study was to develop a conceptual model of the adult and pediatric patient experience of IgAN, including disease signs and symptoms, treatment side effects, and impact on functioning and well-being. METHODS: This study comprised a systematic review and thematic analysis of qualitative studies with adults and children diagnosed with IgAN. Data sources were identified through an electronic database search of journal articles (MEDLINE, Embase, PsycINFO; June 2021), hand-searching of conference proceedings, patient advocacy group websites, and gray literature. Non-English articles were excluded. Identified data (patient/caregiver quotes, author summaries, and interpretations of patient experiences) were extracted from articles. Extracted data were qualitatively analyzed, aided by ATLAS.ti v7. Codes were applied to data; concepts (i.e., symptoms) were identified, named, and refined. A conceptual model was developed by grouping related concepts into domains. RESULTS: In total, five sources were identified for analysis: two journal articles, two online anthologies of patient stories, and one patient organization-sponsored "Voice of the Patient" meeting report. Conceptual model symptom domains included swelling/puffiness (edema), pain/aches/discomfort, fatigue, weight gain, sleep problems, urinary problems, and gastrointestinal problems. Impact domains included emotional/psychological well-being, physical functioning/activities of daily living, social functioning, work/school, and relationships. CONCLUSIONS: Secondary analysis of published qualitative literature permitted development of a novel conceptual model depicting the patient experience of IgAN; however, its depth is limited by a lack of available literature. Further qualitative research is recommended to refine and/or confirm the concepts and domains, determine any relationships between them, and explore the outcomes that are most meaningful to patients. The refined model will provide a useful tool to inform the selection, development, and/or amendment of COAs for use in future IgAN clinical trials.

Development of a Conceptual Model for the Patient Experience of Focal Segmental Glomerulosclerosis (FSGS): A Qualitative Targeted Literature Review.

INTRODUCTION: Focal segmental glomerulosclerosis (FSGS) is a leading cause of kidney disease and can progress to end stage kidney disease (ESKD). An overview of symptoms and impacts of the disease experienced will help inform the selection or development of fit-for-purpose clinical outcome assessments (COA) to be used in FSGS clinical trials. This study aimed to develop a conceptual model (CM) of the adult and pediatric patient experience of FSGS including disease signs/symptoms, treatment side-effects, and impact on functioning and wellbeing. METHODS: This study comprised a systematic review and thematic analysis of qualitative studies with adults and pediatric patients diagnosed with FSGS. Data sources were identified through an electronic database search of journal articles (Medline, Embase, PsycINFO; June 2021) and hand-searching of conference proceedings, patient advocacy group websites, and gray literature. Non-English articles were excluded. Identified data (patient/caregiver quotes, author summaries, and interpretations of patient experiences) were extracted from the articles. Extracted data were qualitatively analyzed aided by ATLAS.ti v7. Codes were applied to data and concepts (symptoms/impacts) were identified, named, and refined. A CM was developed by grouping related concepts into domains. RESULTS: In total, 12 sources were identified for analysis: 6 journal articles and 6 series of patient testimonials. Salient sign/symptom/side-effect domains included swelling/puffiness (edema), pain/aches/discomfort, fatigue, weight changes, skin problems, respiratory problems, and sleep problems. Salient impact domains included emotional/psychological wellbeing, physical functioning/activities of daily living, social functioning, and work/school. CONCLUSION: Secondary analysis of published qualitative literature permitted development of a CM describing the adult and pediatric experience of FSGS. Concept elicitation interviews are recommended to refine the CM, confirm the salient/most bothersome concepts, and confirm the extent of impact on daily life. The refined CM will provide a useful tool to inform the selection, development, and/or amendment of COAs for use in future FSGS clinical trials.

Drug Discovery and Development in Rare Diseases: Taking a Closer Look at the Tafamidis Story.

Rare diseases are increasingly recognized as a global public health priority. Governments worldwide currently provide important incentives to stimulate the discovery and development of orphan drugs for the treatment of these conditions, but substantial scientific, clinical, and regulatory challenges remain. Tafamidis is a first-in-class, disease-modifying transthyretin (TTR) kinetic stabilizer that represents a major breakthrough in the treatment of transthyretin amyloidosis (ATTR amyloidosis). ATTR amyloidosis is a rare, progressive, and fatal systemic disorder caused by aggregation of misfolded TTR and extracellular deposition of amyloid fibrils in various tissues and organs, including the heart and nervous systems. In this review, we present the successful development of tafamidis spanning 3 decades, marked by meticulous laboratory research into disease mechanisms and natural history, and innovative clinical study design and implementation. These efforts established the safety and efficacy profile of tafamidis, leading to its regulatory approval, and enabled post-approval initiatives that further support patients with ATTR amyloidosis.

Long-term evaluation of analytical methods used in sirolimus therapeutic drug monitoring.

Results of therapeutic monitoring of sirolimus blood concentrations are assay and laboratory dependent. This study compared performance over time of the IMx microparticle enzyme immunoassay (MEIA), Architect chemiluminescent microparticle immunoassay (CMIA), and liquid chromatography with mass spectrometric detection (LC/MS/MS) as part of a proficiency testing scheme. Pooled samples from sirolimus-treated patients and whole-blood samples spiked with known quantities of sirolimus were assayed monthly between 2004 and 2012. When results of pooled patient samples were compared with LC/MS/MS, the MEIA assay showed an overall mean percent bias of -2.3% ± 11.2% that, although initially positive, became increasingly negative from 2007 through 2009. The CMIA, which replaced the MEIA assay, had a mean percent bias of 21.9% ± 12.3%, remaining stable from 2007 through 2012. Similarly, for spiked samples, the MEIA showed an increasingly negative bias over time vs. LC/MS/MS, whereas CMIA maintained a stable positive bias. Based on comparison of immunoassay measurements on individual patient samples, CMIA values were more than 25% higher than MEIA values. These results highlight the importance of continued proficiency testing and regular monitoring of sirolimus assay performance. Clinicians must be aware of the methodology used and adjust target levels accordingly to avoid potential effects on efficacy and toxicity.