A UK analysis of the cost of switching renal transplant patients from an immediate-release to a prolonged-release formulation of tacrolimus based on differences in trough concentration variability

Background and aims:

Randomized controlled trials have shown that a once-daily prolonged-release (PR) tacrolimus formulation (PR tacrolimus; Advagraf), is non-inferior to a twice-daily immediate-release (IR) tacrolimus formulation (IR tacrolimus; Prograf) in terms of biopsy-proven acute rejection, graft failure and mortality in renal transplant recipients. However, relative to IR tacrolimus, PR tacrolimus exhibits reduced tacrolimus trough concentration variability, which has been associated with reduced graft failure. Based on these data, the present study evaluated the cost of switching UK renal transplant patients from IR tacrolimus to PR tacrolimus.

Methods:

UK-specific data on acute rejection, graft failure, and mortality were used to construct a budget impact model to assess the costs of switching from IR tacrolimus to PR tacrolimus on a 1:1?mg:mg basis. The model assumed that 3.1% of patients on PR tacrolimus had high tacrolimus trough concentration variability compared with 17.4% on IR tacrolimus, based on a study comparing PR tacrolimus and IR tacrolimus pharmacokinetics. A relative graft failure risk of 2.38 was applied to high variability patients based on data from a tacrolimus variability study in which 10/148 patients with low variability experienced graft failure, compared with 24/149 in the high variability group. Cost data were taken from the British National Formulary and 2012–2013 NHS tariff information.

Results:

The mean per-patient cost (including tacrolimus, concomitant immunosuppressive medications, dialysis after graft failure, and treatment for acute rejection) was GBP 26,941 (standard deviation [SD]?=?GBP 2765) with PR tacrolimus vs GBP 30,356 (SD?=?GBP 3085) for IR tacrolimus over a 5-year period, corresponding to a saving of GBP 3415 (SD?=?GBP 516) per patient or GBP 341,500 in a hypothetical 100-patient transplant center. Cost savings were driven primarily by lower dialysis costs resulting from the lower proportion of PR tacrolimus patients with high tacrolimus trough concentration variability (leading to lower graft failure risk).

Limitations:

The main limitation of the study was the use of heterogeneous data sources to capture the effect of within-patient variability on graft failure. The most important difference between the studies was the definition of the threshold between low and high within-patient variability. This was explored in sensitivity analyses in which the inter-arm difference in the inter-arm proportions of patients with high and low variability was abolished.

Conclusions:

Converting UK renal transplant recipients from IR tacrolimus to PR tacrolimus was associated with lower pharmacy and dialysis costs.     

Partial acquisitions in emerging markets: A test of the strategic market entry and corporate control hypotheses

In this paper, we examine the motivations of acquirers undertaking partial acquisitions in emerging markets by testing two competing hypotheses: the market for corporate control hypothesis and the market entry hypothesis. We find that targets of cross-border acquisitions outperform targets of domestic acquisitions in the pre-acquisition period. While cross-border acquisitions have no significant impact on target firms' operating performance, targets of domestic acquisitions experience significant improvements in operating performance and substantial changes in ownership structure after the acquisition. The evidence suggests that domestic partial acquisitions in emerging markets serve as a market for corporate control, while cross-border partial acquisitions are motivated by the strategic market entry rationale.     

An empirical analysis of property appraisal and mortgage redlining

The recent literature advances a hypothesis that addresses the possibility of mortgage redlining caused by a dynamic information externality in property appraisals and mortgage lending. In particular, Lang and Nakamura (1993) hypothesize that because property appraisals depend on past transactions, appraisals in neighborhoods where transactions were infrequent tend to be less precise. The greater uncertainty about house valuation in such neighborhoods can lead mortgage lenders to impose stringent requirements on borrowers. Lang and Nakamura's article, like most economic analysis of property appraisals, is theoretical. Using a sample of mortgages purchased by Fannie Mae, we present preliminary research results that cast doubt on appraisal behavioral rules such as weighted averages or backward-looking expectations on which Lang and Nakamura and other theoretical studies are based. Instead, our results refocus attention on the moral hazard issues of appraisal. We find that in more than 80 percent of the cases, the appraisal is between 0 and 5 percent above the transaction purchase price, in only 5 percent of the cases is the appraisal lower, and in 30 percent of the cases, the appraisal and transaction prices are identical. It would take a strong statistical model to generate such occurrences. Our resutls also indicate that appraisal outcomes are used as a risk factor with different weights for loans with different characteristics (loan-to-value ratios and house prices). The results suggest that more empirical investigation of appraisal practices be conducted to verify the validity of conventional wisdom embedded in theoretical studies, and we offer an econometric framework toward this end.     

Racial and ethnic differences in housing demand: An econometric investigation

This article empirically investigates the sources of housing demand differences between racial (black and white) and ethnic (Hispanic and non-Hispanic) groups. We estimate the tenure-adjusted housing demand equations from the 1989 American Housing Survey (AHS) national sample data and measure the effects of different sources for demand disparities in housing demand, but much less so in explaining racial differences in housing demand. Specifically, 98% (96%) of the housing demand differences between Hispanic and non-Hispanic owners (renters) is due to differences in group endowments. For the racial groups, 29% (51%) of the housing demand differences between black and white owners (renters) is attributable to differences in group endowments. The residual differences explain 71% and 49% of the black-white differentials for owners and renters, respectively. The residual components in our model capture the effect of institutional and structural factors intrinsic to the housing market (such as racial discrimination or residential segregation) and/or the influence of important omitted or harder-tomeasure variables correlated with race or ethnicity (such as wealth, employment history, credit history, and cultural differences in housing consumption).     

Asset specificity,firm heterogeneity and capital structure

This paper presents an empirical investigation of the importance of specialized assets and other unique characteristics of a firm in explaining the variance in capital structure across firms. The results show that firm-specific effects contribute most to the variance in leverage, suggesting a strong link between strategy and capital structure.     

Wealth effects and the current account with endogenous terms of trade

Portfolio balance models of exchange rate dynamics generally neglect diversification in internationally traded goods. They thereby avoid a difficulty in demonstrating that models allowing such diversification are not globally unstable, as highlighted by Dornbusch and Fischer (1980). This note shows that simple perfect foresight versions of traditional endogenous terms of trade models are unambiguously characterized by saddlepoint stability.     

Sensory characteristics of fufu prepared with cassava roots (Manihot esculenta Crantz) stored in polyethylene sacks

This study was carried out to assess the effect of storage of cassava roots in polyethylene sacks for periods of 2, 4, 6 and 8 weeks on the sensory characteristics of cassava fufu, a popular Ghanaian dish. Freshly harvested cassava roots were dipped in tap water and packed into polyethylene sacks in 2‐kg batches and stored at room temperature (25°C ± 1°C). Samples of fresh cassava fufu were evaluated and then at two weekly intervals for a period of 8 weeks. Attributes evaluated were colour, smell, elasticity, smoothness and taste. A structured six‐point ranking scale ranging from 6 (excellent) to 1 (very poor) was used for the evaluation. The data were analysed using analysis of variance, and the least significance difference test at P < 0.05 was used to determine differences between means. The results showed that storage of cassava roots for up to 8 weeks did not significantly affect the colour, smell, elasticity and taste of cassava fufu. However, smoothness of fufu prepared with cassava stored for 6 and 8 weeks was significantly different from the samples of the fresh cassava, and those stored for 2 and 4 weeks. It was concluded that cassava roots stored for periods up to 8 weeks in polyethylene sacks produced fufu of similar characteristics as fresh cassava fufu. This method is therefore recommended for use by homemakers, food service operators, cassava retailers and processors to save them time, energy and money used for the frequent trips for purchases. The method would also reduce post‐harvest losses to a large extent.     

Value Congruence Awareness: Part 1. DNA Testing Sheds Light on Functionalism

This exploratory study examines awareness of the other party's instrumental, terminal, and work values by members of supervisor and employee dyads. Subjective estimates of value congruence, provided by either member of the dyad, correlated with actual value congruence scores determine conscious awareness levels in all cases. Results demonstrate supervisory awareness of employee terminal values, but not work values or instrumental values, even though these latter value types probably possess the greatest relevance to achieving organizational goals. Further, employees possess awareness of supervisor work values but not instrumental or terminal values. These findings challenge traditional assumptions underlying the functionalism position on organizational culture that appears in the literature most frequently read by practicing managers.