Patient and healthcare professional experiences of the Salford Lung Studies: qualitative insights for future effectiveness trials.

BACKGROUND: Randomized controlled trials (RCTs) conducted in the routine care setting provide the opportunity to better understand the effectiveness of new medicines but can present recruitment difficulties. An improved understanding of the challenges/opportunities for patient and healthcare professional (HCP) engagement in clinical research is needed to enhance participation and trial experience. In this study, we explored patient and HCP drivers for, and experiences of, participation in the Salford Lung Studies (SLS), and their views on future trial participation and the overall value of such trials. METHODS: This was a qualitative study set in Salford, UK, comprising patient telephone interviews (N = 10) and HCP advisory boards (one with general practitioners [GPs], one with practice managers [PMs]); all individuals had participated in the SLS. Semi-structured telephone interviews were recorded, transcribed and analysed thematically. Advisory board meetings were analysed based on transcriptions of audio recordings and field notes. RESULTS: For patients, key positive aspects of the SLS were the ease/convenience of study assessments and excellent relationships with study nurses. GPs and PMs considered the SLS to be well-organized and highlighted the value of research nurse support; they also described minor challenges relating to trial systems, initial financial strain on practices and staff turnover. All participants indicated that they were very likely to participate in future trials, citing a design closely aligned with routine care practice as essential. Several strategies to encourage trial participation were suggested, such as clearly communicating benefits to patients and ensuring flexible study assessments. CONCLUSIONS: Patients and HCPs had positive experiences of the SLS. The study design, closely aligned with routine care, was considered important to their high likelihood of participating in future trials. The experiences of patients and HCPs in the SLS provide valuable insights that will help inform future best practice in the design and conduct of future real-world effectiveness RCTs in primary care. The detailed first-hand experiences of HCPs will be of significant value to others considering engaging in clinical research and participating in effectiveness RCTs.

The Humanistic and Economic Burden of Chronic Idiopathic Constipation in the USA: A Systematic Literature Review.

BACKGROUND: Chronic idiopathic constipation (CIC) is a functional gastrointestinal disorder with an estimated prevalence of 16% in the USA; however, the humanistic and economic burden of CIC is poorly characterized. AIM: This systematic literature review aimed to assess the humanistic and economic burden of CIC in adults in the USA. METHODS: Two systematic literature searches of English-language publications on the humanistic and economic burden of CIC in adults in the USA were conducted using electronic databases and other resources. Both searches included the terms "chronic idiopathic constipation" and "functional constipation". Specific terms used in the search on humanistic burden included "quality of life", "SF-36", "SF-12", and "PAC-QOL"; search terms for economic burden included "cost", "resource use", "absenteeism", and "productivity". RESULTS: Overall, 16 relevant articles were identified. Health-related quality of life (HRQoL) appeared to be reduced in patients with CIC compared with controls and the general US population. Abdominal (r=0.33-0.49), stool (r=0.23-0.33), and rectal symptoms (r=0.53) appeared to be associated with reduced HRQoL. Younger age and female sex were associated with reduced overall HRQoL and greater symptom severity. Direct outpatient costs were higher in patients with CIC than those without CIC (US$6284 vs US$5254). Patients with CIC and abdominal symptoms reported more days of disrupted productivity per month than those without abdominal symptoms (3.2 days vs 1.2 days). The overall prevalence of complementary and alternative medicine use by patients with CIC was similar to that in the general US population. CONCLUSION: The reduced HRQoL and increased costs associated with CIC indicate unmet therapeutic need in this disorder. Further research is required to better understand the humanistic and economic burden of CIC in the USA.

Understanding Payer Perspectives on Value in the Use of Pharmaceuticals in the United States.

BACKGROUND: In recent years, value assessment frameworks have been introduced to inform discussions about how to define and assess value in the U.S. health care system. However, there is uncertainty as to how value assessment frameworks and other approaches to achieve value such as outcomes-based contracting are perceived and used in coverage decisions. OBJECTIVE: To understand how U.S. payers determine value in the use of pharmaceuticals and how it differs from payers outside the United States. METHODS: Qualitative in-depth phone interviews with 13 executive-level public and private U.S. managed care representatives and 6 health technology assessment advisors outside the United States were conducted from September to November 2017. RESULTS: Despite various mechanisms used by U.S. payers to assess value, no consistent definitions of value were provided, and U.S. payers felt limited in what they can do to achieve value in pharmaceutical decision making. Value assessment frameworks are not formally considered in formulary and reimbursement decisions but are used as a reference as they become available by most or all U.S. health plans. U.S. payers expressed concerns, including limited control over pharmaceutical pricing and budget caps, and limited ability to use incremental cost per quality-adjusted life-year thresholds. Outcomes-based contracting could have some utility in specific cases where the treatment has a particularly high cost and a clear outcomes measure, but payers indicated that outcomes-based contracts can be difficult to operationalize, and determination of savings was uncertain. Payers outside the United States-who are enabled by government health care bodies, policy tools, and analytical frameworks that have no counterpart in the United States-have a wider array of instruments at their disposal. U.S. payers were largely open to learning from other health care systems outside the United States, particularly the German health care system, where patient-relevant benefit compared with a predetermined treatment comparator is the primary determinant for price negotiations. CONCLUSIONS: Although there is interest in including value assessment frameworks during the decision-making process in the United States, there are significant challenges to operationalizing them. The current environment in the United States restricts payers' ability to make favorable contracts with manufacturers, and changes to the U.S. health system design are needed to facilitate this effort. Adoption of a value assessment framework in Medicare or Medicaid would accelerate adoption of these tools by private payers in the United States. DISCLOSURES: This study was conducted by RTI Health Solutions under the direction of The Pew Charitable Trusts and was funded by The Pew Charitable Trusts. Vekaria is employed by RTI Health Solutions. Reynolds and Coukell are employed by The Pew Charitable Trusts. Brogan and Hogue have nothing to disclose.

Ectonucleotidases in the kidney.

Members of all four families of ectonucleotidases, namely ectonucleoside triphosphate diphosphohydrolases (NTPDases), ectonucleotide pyrophosphatase/phosphodiesterases (NPPs), ecto-5'-nucleotidase and alkaline phosphatases, have been identified in the renal vasculature and/or tubular structures. In rats and mice, NTPDase1, which hydrolyses ATP through to AMP, is prominent throughout most of the renal vasculature and is also present in the thin ascending limb of Henle and medullary collecting duct. NTPDase2 and NTPDase3, which both prefer ATP over ADP as a substrate, are found in most nephron segments beyond the proximal tubule. NPPs catalyse not only the hydrolysis of ATP and ADP, but also of diadenosine polyphosphates. NPP1 has been identified in proximal and distal tubules of the mouse, while NPP3 is expressed in the rat glomerulus and pars recta, but not in more distal segments. Ecto-5'-nucleotidase, which catalyses the conversion of AMP to adenosine, is found in apical membranes of rat proximal convoluted tubule and intercalated cells of the distal nephron, as well as in the peritubular space. Finally, an alkaline phosphatase, which can theoretically catalyse the entire hydrolysis chain from nucleoside triphosphate to nucleoside, has been identified in apical membranes of rat proximal tubules; however, this enzyme exhibits relatively high K (m) values for adenine nucleotides. Although information on renal ectonucleotidases is still incomplete, the enzymes' varied distribution in the vasculature and along the nephron suggests that they can profoundly influence purinoceptor activity through the hydrolysis, and generation, of agonists of the various purinoceptor subtypes. This review provides an update on renal ectonucleotidases and speculates on the functional significance of these enzymes in terms of glomerular and tubular physiology and pathophysiology.

Intraluminal ATP concentrations in rat renal tubules.

It is becoming increasingly recognized that stimulation of apical P2 receptors can influence solute transport in the nephron, but, to date, no information is available on endogenous intraluminal nucleotide concentrations in vivo. This study measured intraluminal ATP concentrations in the renal tubules of anesthetized rats. Proximal tubular concentrations were found to be in the range of 100 to 300 nmol/L, with no significant variation along the S2 segment, whereas concentrations in the early distal tubule were markedly lower. Using collections of varying duration, the half-life of ATP in collected proximal tubular fluid was found to be 3.4 min, indicating significant breakdown by soluble nucleotidases. For assessment of whether proximal tubular ATP was filtered or secreted, experiments were performed in Munich-Wistar rats. The ATP concentration in midproximal tubules (142 +/- 23 nmol/L) was more than four-fold higher than in Bowman's space (32 +/- 7 nmol/L; P < 0.001), whereas fractional water reabsorption between the two sites was modest. In experiments that were designed to determine the effects of (patho)physiologic disturbances on intraluminal ATP, rats were either volume expanded or subjected to hypotensive hemorrhage. Neither maneuver affected proximal tubular luminal ATP concentrations significantly; rapid degradation of secreted ATP by ecto- and soluble nucleotidases is a possible explanation. It is concluded that the proximal tubule secretes ATP into the lumen, where it may have an autocrine/paracrine regulatory role.

Immunolocalization of ectonucleotidases along the rat nephron.

Evidence is accumulating that extracellular nucleotides act as autocrine/paracrine agents in most tissues, including the kidneys. Several families of surface-located enzymes, collectively known as ectonucleotidases, can degrade nucleotides. Using immunohistochemistry, we have examined the segmental distribution of five ectonucleotidases along the rat nephron. Perfusion-fixed kidneys were obtained from anesthetized male Sprague-Dawley rats. Cryostat sections of cortical and medullary regions were incubated with antibodies specific to the following enzymes: ectonucleoside triphosphate diphosphohydrolase (NTPDase) 1, NTPDase2, NTPDase3, ectonucleotide pyrophosphatase phosphodiesterase 3 (NPP3), and ecto-5'-nucleotidase. Sections were then costained with Phaseolus vulgaris erythroagglutinin (for identification of proximal tubules) and antibodies against Tamm-Horsfall protein (for identification of thick ascending limb), calbindin-D(28k) (for identification of distal tubule), and aquaporin-2 (for identification of collecting duct). The tyramide signal amplification method was used when the ectonucleotidase and marker antibody were raised in the same species. The glomerulus expressed NTPDase1 and NPP3. The proximal tubule showed prominent expression of NPP3 and ecto-5'-nucleotidase in most, but not all, segments. NTPDase2 and NTPDase3, but not NPP3 or ecto-5'-nucleotidase, were expressed in the thick ascending limb and distal tubule. NTPDase3, with some low-level expression of ecto-5'-nucleotidase, was also found in cortical and outer medullary collecting ducts. Inner medullary collecting ducts displayed low-level staining for NTPDase1, NTPDase2, NTPDase3, and ecto-5'-nucleotidase. We conclude that these ectonucleotidases are differentially expressed along the nephron and may play a key role in activation of purinoceptors by nucleotides and nucleosides.