Patient perception of generic antiepileptic drugs in the Midwestern United States

Physicians' attitudes toward generic substitutions of antiseizure drugs in epilepsy

OBJECTIVES

The safety of generic substitution of antiseizure drugs (ASDs) has been questioned for many years. This study aimed to identify physicians' attitudes to the generic substitution of ASDs in epilepsy and which factors were of significance when deciding on compound substitutions.

MATERIAL AND METHODS

A cross-sectional web-based survey was sent to neurologists and neurology residents in public health care and at private practices in two Swedish regions between February and March 2020. The 30-item survey covered drug- and patient-related factors, as well as considerations relating to practical, cost-related, and pharmacokinetic issues.

RESULTS

The total response rate was 55.8%. Respondents were generally positive to cutting costs through generic ASD utilization (74%) and prescribing generic compounds when starting a new ASD treatment (84.9%). The most substantial concern was a deterioration in seizure control (17.1%). Physicians refrained from switching if the patient wished to remain on the original compound (76.1%), had a cognitive impairment (52.5%), was on a drug with a narrow therapeutic index (47%), or had shown prior susceptibility to adverse effects (45.6%). Opinions on substitution decisions differed significantly between the Stockholm and Skåne regions. Less than one-third of the respondents were aware of supporting guidelines.

CONCLUSIONS

Neurologists generally accept the use of generic antiseizure compounds. Patient preference to remain on brand-name drug treatment was the most important factor that led to avoiding a switch. Our results may constitute material for consensus discussions to decide on quality indicators of interest for future research on substitution outcomes.

Evaluation of the In-Vitro Dissolution Permeation Systems 1 (IDAS1) as a potential tool to monitor for unexpected changes in generic medicaments in poorly regulated markets

Panama, like most Latin American countries, has insufficient regulatory safeguards to ensure the safety and efficacy of all pharmaceutical products in the market, a situation that results in a two-tier system, where affluent citizens can afford innovator products while poor citizens must consume 'generics' of uncertain quality. Given that one lot of each drug product is analyzed every five years during registration while commercial lots are not, and since most products are not bioequivalent but simply copies or similars, there is a concern that commercial and registration lots of these 'generics' may not be of the same quality. The objective of this study was to assess the ability of various in vitro quality control tests to detect difference among five amlodipine products available in the Panamanian market: four 'generics', made in various countries, and the innovator, made in Germany and used as reference listed drug in Panama (Pan-RLD). The innovator manufactured in the United States (US-RLD) was used to compare the two RLDs. The Content Uniformity test, 30-min Dissolution test and multiple-pH Dissolution Profiles did not show any difference among the products. However, the in vitro dissolution absorption system 1 (IDAS1) showed a statistically significant difference in the amount dissolved between Pan-RLD and three out of the four 'generics', and significantly lower permeated amount for all the 'generics' compared with Pan-RLD; only US-RLD was similar to Pan-RLD. Thus, IDAS1 showed promise as a potential tool that authorities in weakly regulated markets can use to monitor for possible lot-to-lot product changes, which can help improve the quality of pharmaceutical products available to their entire populations. The significance of the similarity between the innovators made in Germany and the United States and their difference from the 'generics' (manufactured in other countries) is not known but deserves investigation.

Widespread skeptic attitudes among people with epilepsy toward generic antiseizure drugs - A Swedish survey study

PURPOSE

To explore associations between the characteristics of people with epilepsy (PWE) and their attitudes toward generic substitution of antiseizure drugs (ASDs) in epilepsy.

METHODS

This was a cross-sectional survey study directed at adults with epilepsy using selected brand drugs: Keppra®, Lamictal®, Lyrica® or Topimax®. Symptoms of anxiety and depression, sense of self-efficacy, and beliefs about medicines were assessed. Caregivers were asked to answer for persons with intellectual or communicative difficulties.

RESULTS

The total response rate was 41% (n = 178). Almost half (46%) of subjects stated that they would oppose generic substitution (Gen-NEG) if suggested by their neurologist, while 71% would worry about adverse effects and/or increased seizure frequency after a putative switch. Age ≥50 increased the odds of being Gen-NEG (adjusted OR: 2.20, 95% CI: 1.18-4.11). Negative associations with both Gen-NEG and worriers were found for education level of high-school diploma or above, employment/studies, and prior experience of generic ASD switch. The proportion of worriers was much higher among caregivers (21/22) compared to subjects with epilepsy (106/156).

CONCLUSION

High proportions of PWE express concerns regarding generic substitution of ASDs. The elderly and caregivers seem to express particular concerns. Identifying ways to diminish negative outcomes and worries in connection with a switch is an important future field of research in order to ensure high quality, cost-effective health care for the most vulnerable people in our societies.

Effects of generic exchange of solid oral dosage forms in neurological disorders: a systematic review

Background Generic drug exchange is common practice in most healthcare systems. While generics certainly contribute to economic savings, the altered drug formulation might be associated with potential therapeutic problems. Given the narrow therapeutic windows in neurologic indications, any detrimental effect on the therapy can lead to significant consequences. Aim of the review This review aims to investigate potential problems related to a switch from brand-name to generic or from generic to generic drug products in patients with neurologic diseases. Method The review was conducted following the PICO framework and the PRISMA guidelines. MEDLINE and Scopus databases were searched for articles published in English and German language between January 1, 1995 and October 17, 2018. Studies included in this review were randomized controlled studies, reviews, systematic reviews, overviews, cohort studies and case-control studies. Studies excluded were letters, comments, authors view, congress or seminar papers and studies with a focus on economic impact or costs. Results were synthesized qualitatively. The primary outcomes were pharmacokinetic parameters such as the area under the curve (AUC), the peak serum concentration (c_max) or the time at which c_max is observed (t_max). Results The search identified 67 studies with a great variety of endpoints and study designs. The leading indication was epilepsy. Two small RCTs were found on lamotrigine switch. Analysis of the other studies found no significant differences in pharmacokinetic parameters when switching to generic drugs. A more heterogeneous picture was revealed regarding hospitalizations, breakthrough seizures, failure of therapy, adherence and patient concerns. Conclusion While most reports were of poor quality, lamotrigine was the drug with the best available data. Summarizing the results of the available studies, pharmacokinetic parameters of antiepileptic drugs show low deviation. In contrast, data on clinical parameters are less consistent. Some studies found increased seizure frequencies and adverse-drug events, while others showed no complications. Adherence and patient satisfaction seemed to be impaired. In daily practice, generic exchange in epilepsy should be a carefully balanced decision, conducted with great caution. Further research is needed, especially regarding neurologic indications other than epilepsy.

Development and validation of a tool to assess knowledge and attitudes towards generic medicines among students in Greece: The ATtitude TOwards GENerics (ATTOGEN) questionnaire

INTRODUCTION

The use of generic medicines is a cost-effective policy, often dictated by fiscal restraints. To our knowledge, no fully validated tool exploring the students' knowledge and attitudes towards generic medicines exists. The aim of our study was to develop and validate a questionnaire exploring the knowledge and attitudes of M.Sc. in Health Care Management students and recent alumni's towards generic drugs in Greece.

MATERIALS AND METHODS

The development of the questionnaire was a result of literature review and pilot-testing of its preliminary versions to researchers and students. The final version of the questionnaire contains 18 items measuring the respondents' knowledge and attitude towards generic medicines on a 5-point Likert scale. Given the ordinal nature of the data, ordinal alpha and polychoric correlations were computed. The sample was randomly split into two halves. Exploratory factor analysis, performed in the first sample, was used for the creation of multi-item scales. Confirmatory factor analysis and Generalized Linear Latent and Mixed Model analysis (GLLAMM) with the use of the rating scale model were used in the second sample to assess goodness of fit. An assessment of internal consistency reliability, test-retest reliability, and construct validity was also performed.

RESULTS

Among 1402 persons contacted, 986 persons completed our questionnaire (response rate = 70.3%). Overall Cronbach's alpha was 0.871. The conjoint use of exploratory and confirmatory factor analysis resulted in a six-scale model, which seemed to fit the data well. Five of the six scales, namely trust, drug quality, state audit, fiscal impact and drug substitution were found to be valid and reliable, while the knowledge scale suffered only from low inter-scale correlations and a ceiling effect. However, the subsequent confirmatory factor and GLLAMM analyses indicated a good fit of the model to the data.

CONCLUSIONS

The ATTOGEN instrument proved to be a reliable and valid tool, suitable for assessing students' knowledge and attitudes towards generic medicines.

What do people really think of generic medicines? A systematic review and critical appraisal of literature on stakeholder perceptions of generic drugs

BACKGROUND

Considerable emphasis is presently being placed on usage of generic medicines by governments focussed on the potential economic benefits associated with their use. Concurrently, there is increasing discussion in the lay media of perceived doubts regarding the quality and equivalence of generic medicines. The objective of this paper is to report the outcomes of a systematic search for peer-reviewed, published studies that focus on physician, pharmacist and patient/consumer perspectives of generic medicines.

METHODS

Literature published between January 2003 and November 2014, which is indexed in PubMed and Scopus, on the topic of opinions of physicians, pharmacists and patients with respect to generic medicines was searched, and articles within the scope of this review were appraised. Search keywords used included perception, opinion, attitude and view, along with keywords specific to each cohort.

RESULTS

Following review of titles and abstracts to identify publications relevant to the scope, 16 papers on physician opinions, 11 papers on pharmacist opinions and 31 papers on patient/consumer opinions were included in this review. Quantitative studies (n = 37) were the most common approach adopted by researchers, generally in the form of self-administered questionnaires/surveys. Qualitative methodologies (n = 15) were also reported, albeit in fewer cases. In all three cohorts, opinions of generic medicines have improved but some mistrust remains, most particularly in the patient group where there appears to be a strongly held belief that less expensive equals lower quality. Acceptance of generics appears to be higher in consumers with higher levels of education while patients from lower socioeconomic demographic groups, hence generally having lower levels of education, tend to have greater mistrust of generics.

CONCLUSIONS

A key factor in improving confidence in generic products is the provision of information and education, particularly in the areas of equivalency, regulation and dispelling myths about generic medicines (such as the belief that they are counterfeits). Further, as patient trust in their physician often overrules their personal mistrust of generic medicines, enhancing the opinions of physicians regarding generics may have particular importance in strategies to promote usage and acceptance of generic medicines in the future.

Pharmacy switch of antipsychotic medications: patient's perspective

BACKGROUND AND AIM

Several studies have raised concerns over consequences of brand-to-generic and generic-to-generic pharmacy-generated medication substitutions in psychiatric and non-psychiatric patients. The purpose of this retrospective study was to assess behavioral and emotional responses of patients with schizophrenia to antipsychotic medication substitution performed by pharmacies.

METHODS

A group of Polish ambulatory patients with schizophrenia (n = 196) chronically treated with antipsychotic medications were asked whether antipsychotic medication substitution had been proposed by a pharmacist in the last 12 months. Ninety-nine patients answering positively were administered more questions addressing the patient's emotional and behavioral response to the pharmacy proposal.

RESULTS

The most important findings of the present study can be summarized as follows: (1) approximately half of the patients were confronted with a pharmacy proposal to switch their antipsychotic medications in the last 12 months, (2) one quarter of these patients did not accept the pharmacy switch, (3) a substantial proportion of patients (>40 %) did not receive any explanation from a pharmacist offering medication substitution, (4) pharmacy-generated substitution proposals were mainly associated with negative patient attitudes and negative emotional responses, (5) substitution proposals provoked an unscheduled psychiatric visit in approx. 10 % of patients, (6) despite the negative attitudes reported by patients, the pharmacy switch rarely led to treatment discontinuation, but did provoke a change in drug dosing in 7 % of patients accepting the switch.

CONCLUSIONS

A pharmacy proposal to switch their antipsychotic medications is a relatively common experience of Polish ambulatory patients with schizophrenia. Pharmacy-generated substitution proposals are mainly associated with negative patient attitudes, but rarely lead to antipsychotic treatment discontinuation in this group of patients.

Patient perceptions of generic medicines: a mixed-methods study

INTRODUCTION

In an attempt to benefit from the cost-savings associated with use of generic medicines, in June 2013 Ireland introduced generic substitution and reference pricing for the first time. However, perceptions of Irish patients towards generic medicines have not been published previously. Therefore, the objective of this study was to assess how generic medicines were perceived amongst patients in the time leading up to the enactment of the new legislation.

METHODOLOGY

A total of 42 patients were recruited from general practices affiliated with the Graduate Entry Medical School at the University of Limerick and from community pharmacies. Interviews were semi-structured and included quantitative assessments of opinions using 15 structured questions and a five-point Likert scale response system. Interview transcripts were coded and thematically analysed using NVivo (version 9), for qualitative data. Quantitative data were analysed using SPSS (version 20).

RESULTS

Nearly one-third (31 %) of patients had no knowledge of generic medicines and 39 % of those exhibited confusion between the words 'generic' and 'genetic'. Almost one-quarter (24 %) held the view that generics were of poorer quality than originators, while 18 % expressed the opinion that generics do not work as well as originator products. Approximately one-third (30 %) of patients believed that generics were manufactured to a poorer quality, with 29 % holding the view that generics are less expensive due to being of inferior quality. Nearly 90 % of patients stated they would take a generic medicine if it were prescribed by their GP; however, 24 % of patients stated a preference, if offered a choice, for the originator medication. Additionally, a majority of patients (86 %) were in favour of reference pricing and generic substitution. Of the patients interviewed, 50 % stated that a leaflet, or similar, with appropriate, understandable, and accessible information regarding generic medicines would be of use to them.

CONCLUSION

This is the first study of patients' attitudes towards generic medicines in Ireland. Conducted in the time period leading up to the implementation of legislation promoting the use of generic medicines, it highlights variable knowledge about generic medicines among this key stakeholder group. Although patients are supportive of their more widespread use, concerns regarding safety, clinical effectiveness, and manufacturing quality of generic medicines were identified.

Bioequivalent antiepileptic drug switching and the risk of seizure-related events

BACKGROUND

Older antiepileptic drugs (AEDs) are known to have a narrow therapeutic index. As a consequence, switching between bioequivalent AEDs remains controversial in the management of epilepsy. We investigated the association between A-rated switching of each class of currently available AED and emergent treatment for a seizure-related event.

METHODS

We used a case-control method and claims data from the 2010 to 2011 Truven Health MarketScan(®) Commercial Claims Database to estimate the risk of seizure following a medication switch. Cases and controls with an epilepsy diagnosis were identified by emergency/inpatient or outpatient visit claims, respectively. Cases and controls (N=9110) were matched 1:1 by age, epilepsy diagnosis category and seizure medication. The exposure was defined as a switch between A-rated AEDs during the 90 days prior to index date. Conditional logistic regression was used to estimate the association, adjusting for gender, baseline Deyo-Charlson Comorbidity Index (0, 1, 2, or 3+), region (Northeast, Central, South, and West), and total AED medications.

RESULTS

A switch between A-rated AEDs occurred in 1053 (23.2%) cases and 827 (18.1%) matched controls. The unadjusted and adjusted odds ratios of a seizure-related event for switching were 1.38 (95% CI: 1.25-1.52) and 1.27 (95% CI: 1.14-1.41), respectively. The independent risk of an event also increased with each category increase in the Charlson score (CCI=1: 1.17, 95% CI: 1.02-1.33; CCI=2: 1.33, 95% CI: 1.09-1.62; CCI=3+: 1.99, 95% CI: 1.64-2.41). Older AEDs had infrequent switches compared to newer agents and were not associated with events.

DISCUSSION

We found a modest association between AED switching and seizure-related events. Our analysis suggests that the behavior of switching alone may lead to seizure-related events regardless of the medication or type of switch. Other disease or environmental characteristics may contribute to this association. Based on these and other findings, health care professionals and patients should be cautious about switching bioequivalent AEDs.

Generic substitution of antiepileptic drugs--a survey of patients' perspectives in Germany and other German-speaking countries

In this study, we sought to determine the patients' attitudes towards generic substitution of antiepileptic drugs (AEDs) and their experiences with the usage of generic antiepileptic drugs in Germany and other German-speaking countries. A questionnaire was designed for a cross-sectional study. Two thousand copies of the questionnaire were delivered with a magazine edited by a patients' organization. Additionally, the questionnaire was placed on the internet platform of another patients' organization. Thirty-two percent of the patients who already experienced a switch to generic AEDs complained of problems with the switch. Patients who answered the magazine survey worried significantly more about generic substitution of AEDs than patients who answered the internet version. Patients who had never switched were more concerned about generic substitution than those who had already switched. Moreover, patients' beliefs differed between the use of generic drugs in acute medical conditions such as pain and infections and the use of generic AEDs in epilepsy.

Generic antiepileptic drug prescribing: a cross-sectional study

The use of generic antiepileptic drugs (AEDs) in patients with epilepsy is controversial. The purpose of this study is to identify patient characteristics associated with increased odds of receiving a generic AED product. A large commercial database was used to identify patients with a primary diagnosis of epilepsy who were prescribed an AED during a three-month window. Data analysis found that those ≥65 years old had 15.7% greater odds of receiving a generic AED (OR = 1.157; 95% CI = 1.056-1.268). Patients with Medicaid were found to have 2.44 times the odds of having had a generic AED prescription (OR = 2.44; CI = 2.168-2.754). Patients residing in the Northeast had 12.6% decreased odds of receiving a generic AED (OR = 0.874; C I= 0.821-0.931). These patient characteristics could signify certain health care disparities and may represent potential confounders to future observational studies.

Generic immunosuppression: deciphering the message our patients are receiving

BACKGROUND

The introduction of generic immunosuppressants elicited controversy within the transplant community and it is unknown whether patient attitudes mirror the ambiguity of provider perceptions. With the current health care economic crisis, it is necessary to consider generic immunosuppression as an option. A greater understanding of patient perceptions would enhance vital communication between providers and patients to facilitate education and appropriate monitoring.

OBJECTIVE

To evaluate transplant recipients' perceptions of generic versus brand immunosuppressants based on experience with these agents and the willingness of patients to convert treatment from brand to generic formulations based on socioeconomic variables and baseline demographics.

METHODS

Key informant interviews were conducted to inform the development of the survey instrument. The survey was distributed to solid organ transplant recipients at a large, academic medical center from October to December 2010.

RESULTS

Nine patients participated in key informant interviews. Financial considerations and provider recommendations were the most commonly identified factors to influence perceptions of generic immunosuppressants. A total of 255 patients completed the survey; treatment in 81 (32%) participants had been converted to a generic immunosuppressant. Those currently receiving a generic immunosuppressant expressed higher beliefs of generic and brand equivalency (75% vs 54%, p = 0.006) and an increased willingness to convert treatment to a generic given equivalent cost (51% vs 32%, p = 0.024). African American participants were found to have a decreased belief of generic and brand equivalency compared to other ethnicities (60% vs 75%, p = 0.013). Participants with an annual income of less than $30,000 had higher beliefs of generic and brand equivalency (60% vs 40%, p = 0.0001). Education level and age did not impact beliefs of generic efficacy or willingness to convert therapy.

CONCLUSIONS

Patient ethnicity, income, and experience with generic immunosuppressants appear to contribute to perceptions of generic immunosuppressants. The prevalence of generic immunosuppressant use supports the importance of communication of this issue between providers and patients.

Refilling and switching of antiepileptic drugs and seizure-related events

We sought to estimate the risk of seizure-related events associated with refilling prescriptions for antiepileptic drugs (AEDs) and to estimate the effect of switching between brand-name and generic drugs or between two generic versions of the same drug. We conducted a case-crossover study using health-care databases from British Columbia, Canada, among AED users who had an emergency room visit or hospitalization for seizure (index seizure-related event), defined using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9) codes 345.xx (epilepsy and recurrent seizures) and 780.3x (convulsions), between 1997 and 2005. AED prescription refilling itself was associated with 2.3-fold elevated odds of seizure-related events when the refill occurred within 21 days before the index event (odds ratio (OR) 2.31; 95% confidence interval (CI) 1.56-3.44). The OR was 2.75 (95% CI 0.88-8.64) for refills that involved switching, yielding a refill-adjusted OR for switching of 1.19 (95% CI 0.35-3.99). Refilling the same AED prescription was associated with an elevated risk of seizure-related events whether or not the refill involved switching from a brand-name to a generic product.

Generic and therapeutic substitutions in the UK: are they a good thing?

There is considerable interest and debate concerning the place of generic substitution (switching from a brand to generic product); and on therapeutic substitution, that is, switching to a cheaper, but apparently equivalent, product, usually within the drug class. Generic substitution by pharmacists is standard practice in UK hospital settings, and is being proposed for implementation in primary care. Although most prescriptions are already written generically (83% in the community in England in 2008), there are still cost savings that could be made if generic medicines are substituted against prescriptions written by branded name or by getting prescribers to adhere to advice to prescribe generically. Therapeutic substitution is more contentious, as direct evidence to support equivalence is normally lacking. However, the price differential between established drugs whose patents have expired and for which generics are available and newer, branded medicines within the same therapeutic class, makes therapeutic substitution an attractive application of cost-minimization analysis for the more efficient use of healthcare resources. Here we explore the tension that exists between the clinical appropriateness and safety of switching from an individual patient perspective and the consideration of value for money which is required to maximize population health from a health service perspective. Although substitution may affect individual patients (such as, for instance, reduced adherence, increased potential for medication error), it might be a price worth paying given the opportunity cost associated with the use of medicines that are clinically no better than cheaper alternatives.

Seizure outcomes following the use of generic versus brand-name antiepileptic drugs: a systematic review and meta-analysis

The automatic substitution of bioequivalent generics for brand-name antiepileptic drugs (AEDs) has been linked by anecdotal reports to loss of seizure control. To evaluate studies comparing brand-name and generic AEDs, and determine whether evidence exists of superiority of the brand-name version in maintaining seizure control. English-language human studies identified in searches of MEDLINE, EMBASE and International Pharmaceutical Abstracts (1984 to 2009). Randomized controlled trials (RCTs) and observational studies comparing seizure events or seizure-related outcomes between one brand-name AED and at least one alternative version produced by a distinct manufacturer. We identified 16 articles (9 RCTs, 1 prospective nonrandomized trial, 6 observational studies). We assessed characteristics of the studies and, for RCTs, extracted counts for patients whose seizures were characterized as 'controlled' and 'uncontrolled'. Seven RCTs were included in the meta-analysis. The aggregate odds ratio (n = 204) was 1.1 (95% CI 0.9, 1.2), indicating no difference in the odds of uncontrolled seizure for patients on generic medications compared with patients on brand-name medications. In contrast, the observational studies identified trends in drug or health services utilization that the authors attributed to changes in seizure control. Although most RCTs were short-term evaluations, the available evidence does not suggest an association between loss of seizure control and generic substitution of at least three types of AEDs. The observational study data may be explained by factors such as undue concern from patients or physicians about the effectiveness of generic AEDs after a recent switch. In the absence of better data, physicians may want to consider more intensive monitoring of high-risk patients taking AEDs when any switch occurs.

Bioequivalence of antiepileptic drugs: how close is close enough?

During the past few years, the use and substitution of generic antiepileptic drug products has been increasing both in the United States as well as globally. Although these less expensive products may represent an important alternative for many patients, there may be reasons for concern. Despite well-controlled regulatory studies, concerns persist regarding potential therapeutic inequivalence in some patients with epilepsy. These concerns have prompted some in the US neurology community as well as patient advocacy groups to question the current regulatory requirements for both establishing bioequivalence as well as product substitution. In addition, recent data have questioned the actual cost savings associated with generic substitution in this unique patient population. This article reviews current regulatory requirements and pharmacokinetic, biopharmaceutical, and clinical outcome issues that clinicians, pharmacists, and policymakers should consider regarding generic substitution of these complicated agents.

Understanding patients' perspective in the use of generic antiepileptic drugs: compelling lessons for physicians to improve physician/patient communication

Background

Epilepsy is a condition in which consistency of treatment is paramount to successful management and for most patients, effective seizure control can be achieved. Given the severe consequences of even a single breakthrough seizure, patients should be afforded every opportunity to succeed on their given regimens.

Discussion

Some experts argue that global policy on generic antiepileptic drug substitution in epilepsy should be limited – occurring at the discretion of and with careful monitoring by the physician. While the debate continues, physicians still have daily responsibilities to their patients to help them best manage their epilepsy within the context of the current environment – the reality of which may involve switching to a generic antiepileptic drug or navigating various formulations between generics.

Summary

To provide context, this paper first reviews the main "hot button" issues fueling the ongoing generic debate, including a broad overview of the current state of the literature. The main goal however is to provide physicians with a patient perspective on generic antiepileptic drug use in epilepsy as a source of clinically useful, everyday advice to improve communication and increase patient self-advocacy, both of which are necessary for optimal patient outcome.