Challenges of therapeutic substitution of drugs for economic reasons: focus on CVD prevention

Generic Substitutions and Therapeutic Interchanges in Hospital Pharmacies: A Qualitative Study from Western Saudi Arabia

Background: The aim of the present study was to understand hospital pharmacists' views and practices regarding generic substitution and therapeutic interchange. Method: This was a qualitative study involving pharmacists from three Western Saudi governorates: Taif, Makkah, and Jeddah. It included respondents from the Ministry of Health (MoH), military and private hospitals. Pharmacists were selected using a convenient sampling technique and data were collected using a structured face-to-face interview. Results: Fifty-seven pharmacists agreed to participate in this study. In MoH and private hospitals, generic substitution is a pharmacist-initiated act, while therapeutic interchange requires physician approval. Medication unavailability, side effects, patient characteristics, outcomes, and economic status justified most substitution decisions. In military hospitals, both types of substitutions are controlled by an auto-switch policy and physicians should be informed. In all hospitals, there are policies regulating substitution. Medications eligible for interchange mentioned by pharmacists from different hospitals were comparable to some extent. Pharmacists from the private sector considered substitution a supportive economic measure for both hospitals and patients. Most pharmacists highlighted that patient convenience and physician approval are the most challenging situations in substitution practice. Conclusions: An enhanced understanding of substitution and knowledge about medications included in the hospital formulary will be valuable support to the implementation of substitution practice which responds to the patients' needs to improve their outcomes.

Pharmacists' considerations on non-medical switching at the hospital: a systematic review of the economic outcomes of cost-saving therapeutic drug classes

OBJECTIVES

Non-medical switching (NMS) strategies have the capacity to reduce overall costs in hospitals while maintaining a high level of care. However, the most appropriate diseases and/or medicines for NMS strategies are still vague. The aim of this review was to give a state-of-the-art summary regarding the economic outcomes resulting from the use of NMS strategies and to discuss whether they would be implementable in a hospital inpatient setting.

METHODS

A systematic literature search was conducted in Medline, Embase, and ScienceDirect. Studies published between 1988 and 2018 were included if they evaluated the economic impact of NMS strategies or if they performed an economic evaluation between two drugs. Studies regarding antineoplastic agents, endocrine therapies, and immunostimulants, or immunosuppressants, and biosimilars were excluded.

RESULTS

Fifty (69%) studies assessing an NMS strategy and 22 (31%) studies comparing two medicines were allocated to four categories: prospective studies (n=8, 11%); retrospective chart reviews (n=29, 40%); retrospective claims analysis (n=13, 18%); and retrospective data analysis (n=22, 31%). Hypercholesterolemia, peptic ulcer, and gastro-oesophageal reflux diseases, diabetes mellitus, and venous thromboembolism were the most prevalent diseases in studies evaluating an NMS strategy. Sixty-eight per cent of the included papers reported a reduction in costs with no significant changes in health outcomes and 8 per cent reported a deterioration in health outcomes and/or increased costs.

CONCLUSION

Regardless of the exclusion of studies regarding biologics or medicines used in oncology, the review highlights that NMS strategies with medicines whose management do not require a thorough clinical assessment were associated with reduced costs and no significant changes in patients' health outcomes, in the inpatient setting. NMS strategies targeting medicines that require an extensive clinical assessment should be evaluated using hospital-specific effectiveness and/or utility data prior to their implementation.

Comparison between Branded and Generic Furosemide 40 mg Tablets Using Thermal Gravimetric Analysis and Fourier Transform Infrared Spectroscopy

Background and Purpose

There has been a long-standing belief that generic drugs are of lower value in comparison to their branded name counterparts. They are in particular under scrutiny due to their low market price. Even though the reduction in costs is largely based on skipping expensive preclinical studies and clinical trials for generic drugs, the purity and quality of the raw materials in the production of generic drugs is debatable. Thus, the objective of the study was to analyze and assess the quality comparability of generic furosemide 40 mg (FSD) tablets to branded product available in the market.

Materials and Methods

Quality control tests, in vitro drug release assessments, and thermal analysis investigations for both analog products of FSD were performed. Various physical parameters related to the tablet quality, such as hardness, weight variation, and friability tests, were examined. In vitro drug release behavior evaluations were conducted according to United States Pharmacopeia (USP) specifications and guidelines, whereas thermal analysis was carried out using thermal gravimetric analysis (TGA), and tablets were further evaluated by Fourier transform infrared (FTIR) spectroscopy.

Results

The results indicated a significant variation between the two products in terms of hardness, weight variation, and friability. This could be correlated to variation appeared in thermal and spectroscopic spectra between the two products using TGA and FTIR. Drug release of FSD was slightly different between both products following incubation in different pH media (1.2, 3.0, and 6.5; 120 min), however, this was in accordance with USP dissolution requirements as < 80% of drug release was obtained within the first 30 min from each product.

Conclusion

This study is a useful example for the independent investigations using thermal and spectroscopic analysis to confirm potential hidden variations between generic and branded products that could not be obtained by the bioequivalence studies.

Prescription switching: Rationales and risks

BACKGROUND

Therapeutic drug switching is commonplace across a broad range of indications and, within a drug class, is often facilitated by the availability of multiple drugs considered equivalent. Such treatment changes are often considered to improve outcomes via better efficacy or fewer side effects, or to be more cost-effective. Drug switching can be both appropriate and beneficial for several reasons; however, switching can also be associated with negative consequences.

AIM

To consider the impact of switching in two situations: the use of statins as a well-studied example of within-class drug switching, and gonadotropin-releasing hormone (GnRH)-targeting drug switching as an example of cross-class switching.

RESULTS

With the example of statins, within-class switching may be justified to reduce side effects, although the decision to switch is often also driven by the lower cost of generic formulations. With the example of GnRH agonists/antagonists, switching often occurs without the realisation that these drugs belong to different classes, with potential clinical implications.

CONCLUSION

Lessons emerging from these examples will help inform healthcare practitioners who may be considering switching drug prescriptions.

Systematic literature review of the methodology for developing pharmacotherapeutic interchange guidelines and their implementation in hospitals and ambulatory care settings

PURPOSE

To summarize literature specific to therapeutic interchange (TI) focusing on methodological approaches in order to develop a list of steps that healthcare facilities can consult when developing pharmacotherapeutic interchange guidelines (PTIGs) in hospitals and primary care centers.

METHODS

A search was conducted in PreMEDLINE, Medline, EMBASE, PsycINFO, and the Cochrane Library up to and including December 2015. PRISMA guidelines were used. The inclusion criteria were articles published on TI: methodology, implementation, guidelines, and position statements of scientific societies. Two authors independently reviewed all articles for eligibility and extracted the data.

RESULTS

A total of 102 articles were selected for full-text review; we included three guidelines on how to effect TI, nine position papers of various scientific societies with regard to TI, two articles dealt exclusively about methodology, three articles consisted of recommendations and perspectives on TI, three articles dealt with legal aspects, four articles examined general implementation procedures, two articles were a post-discharge follow-up of patients who had TI, six were surveys referring to TI, and three were articles on the use of TI in ambulatory care The remaining 67 articles focused on therapeutic groups. Study quality was generally low.

CONCLUSIONS

This review identified articles on TI as published guidelines, recommendations, and studies on TI carried out in hospital settings. As a result, eight fundamental steps were established for obtaining adequate results in the development of TI programs.

Impact of Cost Sharing on Therapeutic Substitution: The Story of Statins in 2006

BACKGROUND

Cost sharing is widely used to encourage therapeutic substitution. This study aimed to examine the impact of increases in patient cost-sharing differentials for brand name and generic drugs on statin utilization on entry into the Medicare Part D coverage gap.

METHOD AND RESULTS

Using 5% Medicare Chronic Condition Warehouse files from 2006, this quasi-experimental study examined patients with hyperlipidemia who filled prescriptions for atorvastatin or rosuvastatin between January and March 2006. Propensity score matching and difference-in-difference regressions were used to compare changes in statin utilization for the study group (patients who were not eligible for low-income subsidies [non-LIS] and had generic-only gap coverage) to those of a control group (LIS patients who faced the same cost sharing before and during the Part D coverage gap). In the final sample, 801 patients in the study group were matched to 801 patients in the control group. We found that, compared to the control group, the study group had a larger decline in any monthly brand-name statin use (-0.24 30-day fills, P<0.001). This was only partially offset by increased monthly generic statin use (+0.06 30-day fill, P<0.001), with an overall drop in any monthly statin use (-0.18 30-day fills, P<0.001). Overall adherence with statins declined (OR 0.81, P<0.001), and statin discontinuation increased (OR 1.62, P<0.001) in the study group as compared to the control group.

CONCLUSIONS

Increases in cost-sharing differentials for brand name and generic drugs on coverage gap entry were associated with discontinuation of statins in Medicare Part D patients with hyperlipidemia.

The nocebo effect: patient expectations and medication side effects

Expectation of treatment side effects is consistently linked with those symptoms being realised. Patient expectations, including those generated by the informed consent process, can have a large influence on the side effects that patients feel after starting a new medical treatment. Such symptoms may be the result of the nocebo effect, whereby the expectation of side effects leads to them being experienced. Side effects may also be due to the misattribution of pre-existing or unrelated symptoms to the new medication. Medical professionals' own negative beliefs about a treatment, especially generic drugs, may further enhance patients' expectations of adverse effects. The news media may also influence expectations, particularly when media attention is directed towards a health or medication scare. This field of research has ethical and clinical implications for both medical professionals and the news media with respect to the level and type of information about treatment side effects that is provided to patients or members of the public.

A review of the differences and similarities between generic drugs and their originator counterparts, including economic benefits associated with usage of generic medicines, using Ireland as a case study

Generic medicines are those where patent protection has expired, and which may be produced by manufacturers other than the innovator company. Use of generic medicines has been increasing in recent years, primarily as a cost saving measure in healthcare provision. Generic medicines are typically 20 to 90% cheaper than originator equivalents. Our objective is to provide a high-level description of what generic medicines are and how they differ, at a regulatory and legislative level, from originator medicines. We describe the current and historical regulation of medicines in the world's two main pharmaceutical markets, in addition to the similarities, as well as the differences, between generics and their originator equivalents including the reasons for the cost differences seen between originator and generic medicines. Ireland is currently poised to introduce generic substitution and reference pricing. This article refers to this situation as an exemplar of a national system on the cusp of significant health policy change, and specifically details Ireland's history with usage of generic medicines and how the proposed changes could affect healthcare provision.

The effect of an apparent change to a branded or generic medication on drug effectiveness and side effects

OBJECTIVE

Generic medications are associated with reduced perceived effectiveness, increased perceived adverse effects, and increased rates of nonadherence compared with brand-name medications. This study examined the effect of an apparent medication formulation change on subjective and objective measures of medication effectiveness and medication side effects.

METHODS

Sixty-two university students participated in a study purportedly testing the effectiveness of fast-acting β-blocker medications in reducing preexamination anxiety. All tablets were placebos. In session 1, all participants received a yellow tablet ("Betaprol"). In session 2, participants were randomly allocated to receive Betaprol (no change condition) or a white tablet labeled either as "Novaprol" (branded change condition) or "Generic" (generic change condition). Blood pressure and state anxiety were measured before and after tablet ingestion. Side effects attributed to medication were assessed.

RESULTS

The no change group showed significantly greater decreases in systolic blood pressure (mean [M] [standard deviation] = -7.72 mm Hg, standard error [SE] = 1.45) than the branded change (M = -2.75 mm Hg, SE = 1.44, p = .02) and generic change (M = -3.26 mm Hg, SE = 1.45, p = .03) groups. The no-change group showed significantly greater decreases in state anxiety (M = -1.53, SE = 0.33) than the branded change (M = -0.50, SE = 0.33, p = .03) and generic change (M = -0.52, SE = 0.33, p = .04) groups. Significantly more side effects were attributed to the medication in the generic change (M = 1.83, SE = 0.23) (but not the branded change) condition when compared with the no change condition (M = 0.87, SE = 0.31, p = .03).

CONCLUSIONS

Medication formulation change, particularly to generic medication, seems to be associated with reduced subjective and objective measures of medication effectiveness and increased side effects.

A reappraisal of generic bisphosphonates in osteoporosis

The competitive price of generic bisphosphonates has had a marked effect on practice guidelines, but an increasing body of evidence suggests that they have more limited effectiveness than generally assumed.

INTRODUCTION

The purpose of this study is to review the impact of generic bisphosphonates on effectiveness in the treatment of osteoporosis.

METHODS

This study is a literature review.

RESULTS

A substantial body of evidence indicates that many generic formulations of alendronate are more poorly tolerated than the proprietary preparations which results in significantly poorer adherence and thus effectiveness. Poorer effectiveness may result from faster disintegration times of many generics that increase the likelihood of adherence of particulate matter to the oesophageal mucosa. Unfortunately, market authorisation, based on the bioequivalence of generics with a proprietary formulation, does not take into account the potential concerns about safety. The poor adherence of many generic products has implications for guideline development, cost-effectiveness and impact of treatment on the burden of disease.

CONCLUSIONS

The impact of generic bisphosphonates requires formal testing to re-evaluate their role in the management of osteoporosis.

Cost-effectiveness analysis of valsartan versus losartan and the effect of switching

OBJECTIVES

Losartan will shortly become generic, and this may encourage switching to the generic drug. However, valsartan was shown in a meta-analysis to be statistically superior in lowering blood pressure (BP) to losartan. This paper examines the costs of treatment with these two drugs and the potential consequences of switching established valsartan patients to generic losartan.

METHODS

A US payer cost-effectiveness model was developed incorporating the risk of cardiovascular disease (CVD) events related to systolic blood pressure (SBP) control comparing valsartan to continual losartan and switching from valsartan to generic losartan. The model, based upon a meta-analysis by Nixon et al. and Framingham equations, included first CVD event costs calculated from US administrative data sets and utility values from published sources. The modeled outcomes were number of CVD events, costs and incremental cost per quality-adjusted life-year (QALY) and life-year (LY).

RESULTS

Fewer patients had fatal and non-fatal CVD events with valsartan therapy compared with continual losartan and with patients switched from valsartan to generic losartan. The base-case model results indicated that continued treatment with valsartan had an incremental cost-effectiveness ratio of $27,268 and $25,460 per life year gained, and $32,313 and $30,170 per QALY gained, relative to continual losartan and switching treatments, respectively. Sensitivity analyses found that patient discontinuation post-switching was a sensitive parameter. Including efficacy offsets with lowered adherence or discontinuation resulted in more favorable ratios for valsartan compared to switching therapy.

LIMITATIONS

The model does not evaluate post-primary CVD events and considers change in SBP from baseline level as the sole predictor of CVD risk.

CONCLUSIONS

Valsartan appears to be cost-effective compared to switching to generic losartan and switching to the generic drug does not support a cost offset argument over the longer term. Physicians should continue to consider the needs of individual patient and not cost offsets.

Effectiveness, safety and cost of drug substitution in hypertension

Cost-containment measures in healthcare provision include the implementation of therapeutic and generic drug substitution strategies in patients whose condition is already well controlled with pharmacotherapy. Treatment for hypertension is frequently targeted for such measures. However, drug acquisition costs are only part of the cost-effectiveness equation, and a variety of other factors need to be taken into account when assessing the impact of switching antihypertensives. From the clinical perspective, considerations include maintenance of an appropriate medication dose during the switching process; drug equivalence in terms of clinical effectiveness; and safety issues, including the diverse adverse-event profiles of available alternative drugs, differences in the 'inactive' components of drug formulations and the quality of generic formulations. Patients' adherence to and persistence with therapy may be negatively influenced by switching, which will also impact on treatment effectiveness. From the economic perspective, the costs that are likely to be incurred by switching antihypertensives include those for additional clinic visits and laboratory tests, and for hospitalization if required to address problems arising from adverse events or poorly controlled hypertension. Indirect costs and the impact on patients' quality of life also require assessment. Substitution strategies for antihypertensives have not been tested in large outcome trials and there is little available clinical or economic evidence on which to base decisions to switch drugs. Although the cost of treatment should always be considered, careful assessment of the human and economic costs and benefits of antihypertensive drug substitution is required before this practice is recommended.