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Biomedical subjects

P C Langley

Publications and source records attributed to P C Langley.

At least 19 recordsLinked to original sources
PubMed1999

Modeling the impact of treatment options in genital warts: patient-applied versus physician-administered therapies.

With the availability of new patient-applied treatments for genital and perianal warts, medical providers, physician groups, and health systems are reassessing the role of physician-administered therapies. Two key questions are: how cost-effective are physician- versus patient-administered therapies and, given patient preferences for the convenience and privacy associated with the latter therapies, which of the 2 presently available treatments-imiquimod and podofilox-is most appropriate? The purpose of this article is to examine, from the perspective of the health care purchaser, these questions and to undertake a pharmacoeconomic analysis of the direct cost-effectiveness of therapy options, given targets being set for the outcomes of genital warts therapy. The analysis employs a synthetic, decision-modeling framework in which data on sustained clearance and the direct costs of treatment are drawn from both clinical studies and previous studies on the resources used to support treatment. Once targets are set-and it is proposed here that physicians should aim for at least a 50% sustained clearance rate for genital warts--it becomes clear that in cost per sustained clearance terms, imiquimod, as first-line therapy, is the most cost-effective intervention. If we compare imiquimod with podofilox as first-line therapy (with cryotherapy as the second-line option), the cost per sustained clearance for the imiquimod treatment sequence is $1367 compared with the podofilox-initiated sequence of $1508.

Condylomata Acuminata↗
PubMed1999

The technology of metered-dose inhalers and treatment costs in asthma: a retrospective study of breath actuation versus traditional press-and-breathe inhalers.

This paper reviews the impact of the use of technologically dissimilar beta-agonist aerosols--the Maxair Autohaler (pirbuterol acetate) breath-actuated aerosol and the traditional albuterol press-and-breathe inhaler-on the treatment costs of asthma. If, as clinical evidence would suggest, the breath-actuated aerosol is not only as effective as an albuterol inhaler with a spacer, but is easier to use and results in more optimal beta-agonist use by patients, then one might consider the hypothesis that patients possessing a breath-actuated inhaler would, ceteris paribus, experience lower asthma-related treatment costs-principally, those medical costs associated with fewer emergency room visits and hospitalizations. This hypothesis is considered from the perspective of a retrospective claims database study of patients who used one or the other beta-agonist inhaler exclusively. At the descriptive level, costs of treatment for patients using the press-and-breathe inhaler are estimated to be 16.5% greater than costs for patients using the breath-actuated inhaler. In the multivariate analysis, the presence of the breath-actuated inhaler (in a dummy variable analysis) was not only statistically significant (P < 0.05), but entered with the expected negative sign. Estimated cost impacts under various model specifications are consistent with the magnitude of the cost differences reported in the descriptive analysis. Total cost savings with the Maxair Autohaler ranged from 8.7% to 11.7%, with medical cost savings estimated at 14.6%.

Adrenergic beta-Agonists↗
PubMed1999

Meeting the information needs of drug purchasers: the evolution of formulary submission guidelines.

The emergence of formulary submission guidelines in the 1990s has been seen by many as an attempt to come to grips with the issue of drug management within health systems and to provide, for the first time, a coherent and methodologically rigorous approach to formulary selection. Judging from the available evidence, however, guidelines have fallen far short of their potential. The purpose of this paper is to consider what role guidelines have played in health system management and whether they play a useful role in providing a methodologically sound basis for drug-impact assessment. Two polar cases in guideline development are examined: the Australian guidelines first published in 1992 and now undergoing a second major revision and the guidelines recently published by Blue Cross and Blue Shield of Colorado and Nevada. The former guidelines represent what can be described as the traditional, clinical paradigm of drug-impact assessment; the latter represent what can be called the system-impact paradigm. The argument put forward is that the Australian guidelines are essentially an anachronism, offering little to those whose principal concern is with the management of health systems. In their emphasis on a hierarchy of evidence and a clinical trial-focused, cost-effectiveness evaluation perspective, they represent a methodologic dead end in a number of important respects. The systems-based approach, on the other hand, with its emphasis on validation of claims and the need to consider a range of drug-impact and risk-management scenarios, offers an analytic framework that, while possibly less rigorous, is likely to contribute significantly to the management of health care systems.

Australia↗
PubMed1999

Formulary submission guidelines for Blue Cross and Blue Shield of Colorado and Nevada. Structure, application and manufacturer responsibilities.

From 1 January 1999, all requests by pharmaceutical manufacturers and others to Blue Cross and Blue Shield (BCBS) of Colorado and Nevada for the listing of new pharmaceutical products or any proposed change to the formulary status of an existing product must be accompanied by a submission which meets the informational and analytical standards set out in the BCBS Guidelines for Formulary Submissions for Pharmaceutical Product Evaluation. These submission requirements relate both to the anticipated therapeutic impact of a new product and to claims made as to its anticipated pharmacoeconomic impact. The guidelines have been developed because BCBS is concerned that decisions to admit a drug to formulary have been based in the past on incomplete information. In order to rectify this situation (and to meet quality control objectives), it has been decided that all submissions to BCBS should meet a common information standard that describes both the characteristics of the product and its expected impact in a disease or therapeutic area. Unlike guidelines that have been introduced in countries such as Australia and the Canadian Province of Ontario, these guidelines take an explicit systems approach to the case a manufacturer must make before a product is considered for formulary listing. While the notion of systems impact requirements is not new, this is the first time that a managed healthcare system in the US has adopted this explicit perspective and notified manufacturers that traditional pharmacoeconomic evaluations may not meet the information needs of drug purchasers. The purpose of this paper is to describe the BCBS formulary guidelines and to demonstrate how manufacturers are expected to meet the information needs of a systems impact perspective in submissions to the pharmacy and therapeutics committee.

Blue Cross Blue Shield Insurance Plans↗
PubMed1999

The cost effectiveness of patient-applied versus provider-administered intervention strategies for the treatment of external genital warts.

OBJECTIVE: External genital warts are one of the fastest growing sexually transmitted diseases in the United States today. Two forms of therapy are available: provider-administered and patient-applied. In the most widely used provider-administered ablative therapies, sustained clearance rates range from 18.5% to 40.1%. With nonablative, patient-applied therapies, which are typically more acceptable to patients, sustained clearance rates range from 19.6% with podofilox gel to 44.0% with imiquimod cream. The purpose of this study, given the range of therapies available, their cost differences, and clinical trial-reported differences in rates of sustained clearance, is to determine which therapy modalities, from the providers' perspective, are the most cost effective and which are likely to be the most acceptable to the patient population. STUDY DESIGN: We consider the cost effectiveness of the two patient-applied therapies as first-line therapy followed by provider-administered ablative treatment as second-line therapy. A decision-analytic model framework is developed, with data drawn both from clinical trials and from previously published studies. RESULTS: When considering a two-stage therapy model, with an average sustained clearance rate of 30% assumed for provider-administered ablative therapies, estimated costs per sustained cleared patient are $1265 for patients initially treated with imiquimod and $1304 for patients initially treated with podofilox gel. CONCLUSIONS: Initial treatment with imiquimod is the preferred intervention option as it yields a 39% greater sustained clearance rate than podofilox gel while being 3% less costly per successful outcome.

Administration, Topical↗
PubMed1997

Pharmacoeconomic model of enoxaparin versus heparin for prevention of deep vein thrombosis after total hip replacement.

The costs of heparin and enoxaparin to prevent deep vein thrombosis (DVT) after total hip replacement in the U.S. treatment environment were compared. A decision model was used in a pharmacoeconomic comparison of subcutaneous enoxaparin and subcutaneous heparin, each given for seven days, for the prophylaxis of DVT. In the model, three outcome pathways could follow prophylaxis: proximal DVT, distal DVT, and no DVT (but with a possible false-positive clinical diagnosis of DVT). Probabilities of thromboembolic events and major bleeding were derived from three randomized clinical trials. Account was also taken of the effects of pulmonary embolism (PE). Pharmacoeconomic studies and expert opinion were relied on for the model's principal resource-use categories and costs for DVT prophylaxis, clinical diagnosis of DVT and PE, and DVT and PE treatment. The outcome of choice for the model was the number of DVT events avoided. Regardless of the trial data used, the total mean cost of enoxaparin prophylaxis ($3336 to $3380) exceeded the cost of heparin prophylaxis ($3292 to $3330). However, enoxaparin was more cost-effective in avoiding DVT than heparin, irrespective of the trial on which the analysis was modeled. A sensitivity analysis involving length of hospital stay and length of prophylactic therapy showed the model to be robust and gave the advantage in all instances to enoxaparin in cost per DVT avoided. A model of enoxaparin versus heparin DVT prophylaxis after total hip replacement showed that enoxaparin was more costly than heparin in overall expected treatment costs but more cost-effective in the avoidance of DVT.

Anticoagulants↗
PubMed1997

Peripheral vascular disorders. A pharmacoeconomic and quality-of-life review.

The purpose of this article is to review the literature on the pharmacoeconomics and quality of life of therapy interventions for patients with peripheral vascular disorders. The paper is in 4 parts. The first presents a framework for the analysis of such drug interventions, which contrasts studies that have a clinical focus with those that take a system or modelling focus and presents a research typology for studies in this area. The second part of the paper reviews pharmacoeconomic studies of selected interventions and assesses their contribution to decision-making within healthcare systems. The particular focus is on the pharmacoeconomics of therapy for atherosclerosis. While there are no studies which have evaluated the overall costs of treatment in this disease area or considered the cost effectiveness of the range of alternative treatment strategies, the issues of good clinical practice and the implicit cost effectiveness of identifying patients for treatment options and prevention strategies has been addressed. The few studies which have considered the cost consequences of particular intervention strategies, specifically pentoxifylline therapy and surgical options, are limited in scope and are difficult to generalise due to their age, their study design or the treating environment from which data are drawn. The third part reviews quality-of-life studies and, once again, assesses their contribution to formulary decision-making. There are no published studies which have compared quality-of-life outcomes associated with alternative treatment approaches or which have reported changes associated with pharmacotherapy in patients with peripheral vascular disorders. Finally, given the dearth of studies in this area, a research agenda is proposed for ongoing investigations.

Cost-Benefit Analysis↗
PubMed1997

Managed care guidelines for the economic evaluation of pharmaceuticals.

Foundation Health Corporation, through its National Pharmacy and Therapeutics Committee, requires all pharmaceutical manufacturers and others who wish products to be considered for formulary listing to meet evidentiary and analytical standards in their submission documentation. This article details the evidentiary and analytical standards required from those making submissions and describes the methodological basis of the guidelines. This is the first time, as far as the authors are aware, that a managed care health system in the United States has required formulary submissions not only to meet clinical and economic evaluation standards, but also to take explicit account of the perspective of the managed care group in applying these techniques. Submissions are required to take what is described as a systems impact perspective. This approach is quite different, in both evidentiary and analytical terms, from standards required by health systems in other countries and standards for the economic evaluation of pharmaceuticals proposed by expert groups in the United States.

Cost-Benefit Analysis↗
PubMed1996

Disease management programs.

Disease management (DM) activities are described, and their implementation and monitoring in managed care organizations are discussed. DM programs involve systematic evaluation of the relationships between treatment options and the associated resource use and patient outcomes for the purpose of providing a given standard of health care at the lowest possible resource cost. A DM arrangement covers a specified disease or therapy intervention for a patient group that may be defined by diagnosis, drug use, prior resource use, or patient characteristics. Often, the partners in a DM arrangement are a managed care organization and a pharmaceutical industry representative or division. The development and monitoring of disease management arrangements are dependent on access to several types of data, and these data are available in managed care plans. A DM arrangement includes interventions to change prescribing patterns or patient compliance and assessment of the effects of these interventions against target outcomes specified in the contract. The agreement that is developed specifies guidelines for treatment and requirements for data collection, monitoring, and reporting that are consistent with the target outcomes. In many DM arrangements, the partners share cost savings and risk; other arrangements involve case management on a capitated basis. A pharmaceutical company involved in risk sharing must change its focus from market share to optimal use of drugs within the total cost of treatment. If a risk-sharing contract covers an entire therapeutic class of drugs, a pharmaceutical company may share risk for the use of other manufacturers' products as well as its own. Disease management contracts must consider the full impact of each treatment option on the health system; the goal should be not simply to decrease the drug budget, but to decrease overall costs for treatment that achieves desired outcomes for specific diseases.

Case Management↗
PubMed1996

The November 1995 revised Australian guidelines for the economic evaluation of pharmaceuticals.

In November 1995, the revised Australian Guidelines for the Economic Evaluation of Pharmaceuticals ('the Guidelines') were published. The new document is to be seen as a measured bureaucratic response to the perceived shortcomings of the August 1992 document. The new document sets substantially more demanding and more rigorous evidentiary standards in the reporting of randomised clinical trials and in the justification of the selected evaluation methodology. It also introduces the requirement for a trial- or efficacy-based preliminary economic evaluation, and it recognises the need, under certain circumstances, to model economic evaluations. Although this document has an immediate appeal to those coming to pharmacoeconomic evaluations from a clinical perspective, the approach taken is unlikely to appeal either to economists (the Guidelines continue to discourage cost-benefit analysis) or to health system evaluators working in a competitive delivery environment (such as the US). The Guidelines, in a US environment, would be seen as not only unreasonable in their evidentiary demands and in the task imposed on evaluators, but limited in their failure to take an explicit modeling or system approach to therapy intervention evaluations.

Australia↗
PubMed1996

Cost effectiveness and the allocation of therapies in a treating population.

The purpose of this paper is to challenge the uncritical use of incremental cost-outcomes ratios as decision variables. A scenario is presented which describes conditions under which increasing costs per unit of outcome prevail. Marginal costs increase as the proportion of patients treated under a given therapy increases. If the health system's objective is to maximise health benefits then patients will be switched until the marginal benefits per dollar expended are equal between the 2 therapies. In an example where the costs of the new therapy are greater, for a given proportion of patients treated, patients are switched from the existing to the new therapy until an equilibrium is achieved in the allocation of therapies among the treating population. At this point, the overall costs of treatment are at a minimum. This outcome could only be predicted if the underlying cost-outcomes functions are known and the consequent patterns of therapy substitution and cost impacts assessed. The paper concludes by raising concerns as to the role of incremental cost-outcomes ratios as decision variables where increasing costs may be expected to prevail and there is failure to consider the implications of these increasing costs in formulary decision making. If increasing costs are present then conventional cost-outcomes and incremental cost-outcomes ratios are of limited utility as decision variables in the choice of therapy options.

Cost-Benefit Analysis↗
PubMed1996

A utility assessment of oral and intravenous ganciclovir for the maintenance treatment of AIDS-related cytomegalovirus retinitis.

The purpose of this study was to determine the magnitude of the difference in patient preference/utility for intravenous (i.v.) ganciclovir compared with oral ganciclovir for maintenance treatment of cytomegalovirus (CMV) retinitis. We used a cross-sectional, interviewer-administered time trade-off (TTO) exercise with hypothetical health state descriptions, based upon data from clinical trials and the published literature. The study was conducted in a private clinic in Sydney Australia, specialising in the care of people with HIV. A total of 80 individuals with HIV infection who had not developed AIDS were administered the TTO instrument. The main outcome measure was the difference between each respondent's utility score for oral and i.v. ganciclovir maintenance therapy. When the 80 HIV-positive patients were presented with information on drug efficacy, adverse effects and mode of administration, 60 (75%) preferred oral ganciclovir, 4 patients preferred i.v. ganciclovir, and 16 were indifferent. The median utilities were 0.837 (oral ganciclovir) and 0.475 (i.v. ganciclovir). The difference in rankings was statistically significant by Wilcoxon's signed-ranks test (Z = -6.69, p < 0.00005). The median utility scores suggest that, all other things being equal, individuals with HIV infection would prefer an oral formulation of ganciclovir to i.v. administration in the event of CMV retinitis infection.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Therapy evaluation, patient distribution, and cost-outcomes ratios.

The purpose of this paper is to argue that the emphasis in the pharmacoeconomic literature on cost-outcomes ratios as key decision variables in determining drug choice is misplaced. Unless strict assumptions are made (and believed) as to the relationship between numbers of patients treated and the marginal costs and outcomes of therapy, the only basis on which an evaluation of alternative therapy options can be made is an equilibrium-to-equilibrium modeling framework. This specifically refers to the assumption that costs and outcomes functions exhibit constant returns to scale. In this framework, given the expected changes of distribution of patients between therapy options, estimates can be made of net changes in overall treatment costs and outcomes.

Drug Costs↗
PubMedDate not supplied

Cost-effectiveness profiles with an expanding treatment population.

In trying to identify the therapeutic impact of a drug, clinical trials eliminate potentially confounding factors such as comorbidities, poor compliance and treatment errors in diagnosis, dosing, and drug interactions. Elimination of these variables means that attempts to use clinical data as the basis for predicting relative cost-effectiveness are fraught with difficulties. In this article a theoretical framework is proposed, which, for a single drug intervention, examines the relationship between assumed patterns of clinical effectiveness, costs of drug delivery, and the proportion of the prospective patient population being treated. Cost-effectiveness profiles are generated to represent both usual-treatment situations and situations where interventions to reduce misdiagnoses, adverse events, and noncompliance attempt to push clinical effectiveness to a maximum (given the existence of comorbidities). Without data describing effectiveness and cost profiles, and unless strict assumptions are made as to effectiveness and cost functions, profiles of cost-effectiveness cannot be predicted.

Cost-Benefit Analysis↗
PubMedDate not supplied

Assessing the input costs of disease management programs.

This paper presents a practical blueprint for modeling and evaluating the costs of disease interventions. Retrospective estimates of therapy costs and analyses of various treatment pathways are critical to projecting the likely cost impacts of disease management programs. This presentation outlines the information requirements necessary to identify baseline costs, to set cost outcomes targets, and to monitor costs over the life of an agreement. The chief components of this process are: (1) developing a framework for input cost analysis; (2) identifying costing requirements for various types of disease management interventions; (3) identifying key classifications in such a cost framework; and (4) identifying principal obstacles to cost assessment.

Costs and Cost Analysis↗