Brand-to-generic levetiracetam switching: a 4-year prospective observational real-life study

Safety of brand name to generic substitution of lacosamide in patients with epilepsy - A prospective single-center observational study

PURPOSE

Lacosamide is a widely used third-generation antiseizure medication. However, there is a lack of evidence regarding the safety of substituting brand-name lacosamide with its generic version. This study aimed to determine the clinical outcomes associated with switching from the brand-name to the generic form of lacosamide (LCM) in patients with epilepsy.

METHODS

This prospective observational study involved patients undergoing treatment with LCM at the university epilepsy clinic. In 2018, the price of the brand-name LCM in Poland increased up to 110-fold compared to generic products. Anticipating that most patients would opt to switch to the generic formulations due to financial constraints, we chose to follow up them prospectively to assess the safety of transitioning from the brand-name to the generic form of LCM.

RESULTS

A total of 81 patients, aged 18-62 years, diagnosed with focal epilepsy and undergoing LCM treatment at our institution, decided to switch from the brand-name (Vimpat) to generic variations (Lacosamide TEVA, Lacosamide Glenmark, and Lacosamide Accord). Following the switch, no significant difference was observed in terms of seizure frequency before and after (p = 0.55, Wilcoxon signed-rank test). Subsequently, adverse events were recorded in four patients (4.9%) during the initial follow-up visit post-switch, including somnolence (2 patients) and dizziness (2 patients). Notably, all adverse events resolved by the second follow-up visit without necessitating treatment modification. Importantly, no patient switched back to brand-name medication CONCLUSION: The generic substitution of lacosamide was found to be generally safe in our study. Nonetheless, to confirm our findings, larger prospective studies are required.

Brand-to-generic Levetiracetam Switch in Patients with Epilepsy: Seizure Control and its Predictors in a Real-world Setting

BACKGROUND: Epilepsy is a common neurological disease. Treatment with original antiepileptic drugs may result in high cost. Levetiracetam (LEV) is a broad-spectrum antiepileptic drug. Several studies showed that generic LEV is safe, effective, and saves cost. There are limited data on predictors of seizure control in persons with epilepsy treated with LEV, particularly switch therapy to generic LEV. METHODS: This study was a comparison study conducted at two tertiary care hospitals. One hospital used an original LEV, while another one switched to generic LEV. The outcomes of the study included seizure control after switching to generic LEV treatment, treatment cost, dosage of LEV, adverse events of LEV, switching therapy to original LEV, emergency room visit, and abnormal laboratory tests. These outcomes were compared between the generic and original LEV. Seizure control defined by free of seizure after switch therapy. Predictors of seizure control were analyzed by multiple logistic regression analysis. RESULTS: During the study period, there were 96 eligible patients and treated with generic LEV in 61 patients (63.54%). Regarding treatment outcomes, the generic LEV group had significantly higher proportions of seizure control (91.80% vs. 45.71%) than the original LEV group. The original LEV group had significantly higher cost than the generic LEV group (65,250 vs. 9500 Baht; p < 0.001). The final model had two factors remaining: Generic LEV and frequency of seizure before switch therapy. Generic LEV was independently associated with seizure control with adjusted OR of 6.35 (95% CI of 1.73, 23.34). CONCLUSION: Switch therapy to generic LEV is an alternative therapy with comparable efficacy, lower cost, and safe. Generic LEV and frequency of seizure attack before switch therapy to generic LEV may be related to seizure control.

Evaluating Therapeutic Equivalence of Generic and Original Levetiracetam in Patients with Epilepsy: A Retrospective Study

The brand interchangeability of antiepileptic drugs (AEDs) is a topic of debate, especially regarding their therapeutic equivalence. This study evaluates the efficacy and tolerability of generic levetiracetam compared to the brand-name equivalent in a routine clinical setting. We conducted a retrospective study, examining patients with stable seizure frequency who received generic levetiracetam after the brand-name drug. During the six-month substitution period, changes in seizure frequency, hospitalization due to seizure exacerbation, adverse events, composite outcomes related to adjusting the AED dosage, and switching back to original levetiracetam were analyzed. Seventy-five patients were enrolled; the majority (85.3%) had focal onset seizures, and almost half (49.3%) had refractory epilepsy. Six months after the substitution, the mean seizure frequency per month was not significantly different (3.15 ± 14.47 vs. 2.77 ± 11.41; p = 0.970). In patients with controlled seizures before the change, the seizure frequency increased significantly (0.56 ± 1.83 vs. 0.03 ± 0.16; p = 0.012). Adverse events occurred in six patients. We have observed recurrent seizures or adverse events from 14 days after the transition. The original drug return rates due to recurrent seizures and adverse events were 5.3% and 1.3%, respectively. Generic levetiracetam might not show therapeutic equivalence to the original molecule, especially in patients adequately controlled by the brand-name drug.

Efficacy and safety of switching from brand-name to domestic generic levetiracetam in children with epilepsy

OBJECTIVES

To study the efficacy and safety of domestic generic levetiracetam in replacement of brand-name levetiracetam in the treatment of children with epilepsy.

METHODS

A retrospective analysis was performed on the medical data of 154 children with epilepsy who received domestic generic levetiracetam in the inpatient or outpatient service of Guangdong Provincial People's Hospital from May 2019 to December 2020. Domestic generic levetiracetam and brand-name levetiracetam were compared in terms of efficacy and safety.

RESULTS

For these 154 children, the epilepsy control rate was 77.3% (119/154) at baseline. At 6 months after switching to domestic generic levetiracetam, the epilepsy control rate reached 83.8% (129/154), which showed a significant increase (P<0.05). There was no significant change in the frequency of seizures from baseline to 6 months after switching (P>0.05). The incidence of refractory epilepsy in children with no response after switching treatment was significantly higher than that in children with response (P<0.05). Before switching, only 1 child (0.6%) experienced somnolence, while after switching, 3 children (1.9%) experienced mild adverse drug reactions, including dizziness, somnolence, irritability, and bad temper.

CONCLUSIONS

Switching from brand-name to generic levetiracetam is safe and effective and holds promise for clinical application, but more prospective randomized controlled trials are required in future.

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.

Use of antiseizure medications and safety of branded versus generic formulations: A comparative study on Tuscan administrative databases

PURPOSE

To assess patterns of use of antiseizure medications (ASMs) and to compare the safety of generic versus branded formulations in terms of admission to hospital or to emergency department (ED).

METHODS

We conducted a drug utilization study with a propensity score-matched design using the administrative databases of the Italian Tuscany region. New users of ASMs during 2015 with no history of neoplasia were considered and their first prescription was classified as: available only as branded (only-B-ASM); branded with generic available (B-ASM); and generic (G-ASM). Patients with G-ASM first prescription were matched with four patients with B-ASM prescription. Participants were followed up for one year or until the date of death or diagnosis of neoplasia. Cox regression models were fitted to estimate the risk of admission to hospital or ED.

RESULTS

We identified 36,601 ASM new-users, including 2094 (6.4%) with only-B-ASM as first prescription, 24,588 (74.9%) with B-ASM, and 5788 (17.6%) with G-ASM. We found no differences in the risk of admission to hospital or ED (Hazard Ratio (HR), 0.92; 95% Confidence Interval (CI), 0.85-1.02) among users of generic ASMs compared to those using branded ASMs.

CONCLUSIONS

In our study population, generic ASMs were used less than branded ones. The similarity in the safety of branded and generic formulations suggests that generic ASMs could be the preferred formulation in current clinical practice resulting in a substantial decrease in the cost of treatment.

Appropriate use of generic and branded antiseizure medications in epilepsy: Updated recommendations from the Italian League Against Epilepsy (LICE)

Generic drugs are increasingly used to treat many diseases including epilepsy. The growing importance of generic antiseizure medications (ASMs) has led the ASMs commission of the Italian League Against Epilepsy (LICE) to review current evidence in the literature about efficacy and safety of these products. Recommendations from other scientific organizations have also been considered to provide an update of the LICE position about their utilization (List of Recommendations). Compared with the previous literature review, randomized controlled trials assessing bioequivalence among branded drugs and generics are currently available. Although some contrasting results have been reported, brand-to-generic switching was effective and tolerable in real-life settings, with similar adverse event ratios. Based on these findings, LICE concluded that, conforming to the rigorous regulation of USA and EU markets, generic ASMs are not inferior to the respective branded, providing a cost advantage for patients starting or replacing monotherapy or add-on, and for those with incomplete seizure control. Branded-to-generic (and vice versa) switching is not recommended (although applicable) during seizure remission, as well as the generic-to-other generic switching. Other recommendations focus on the appropriateness of therapeutic drug monitoring (TDM) when switching is required, paying attention to avoiding the erroneous switch between modified and immediate-release formulations during dispensation. Finally, to support patients' compliance, they should be assured of generics' safety and efficacy and carefully informed with practical advice, particularly when the switching is associated with aspect modifications (e.g. color and shape changes) of the pill or the packaging.

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.

Population Pharmacokinetics and Dosing Recommendations of Levetiracetam in Adult and Elderly Patients With Epilepsy

The objective was to develop and externally validate a population pharmacokinetic model of levetiracetam in adult and elderly patients with epilepsy, and to perform dosing simulations to propose individualized dosing regimens more likely to achieve therapeutic concentrations. This prospective study included 367 plasma samples from 107 patients receiving oral levetiracetam. Samples were analyzed by HPLC-UV. Pharmacokinetic data, as well as patient demographic, clinical characteristics, other drug therapy, and the use of innovator or generic products of levetiracetam, were collected. Population modeling was performed with NONMEM and included internal and external validations of the final model. Simulations were used to propose optimized dosing regimens. The pharmacokinetics of levetiracetam was described by a one-compartment model with first-order absorption and linear elimination. Body surface area had a significant effect on the apparent volume of distribution, as did creatinine clearance (CrCL) over the drug clearance (p < 0.01). The final model performed adequately during external validation testing. The final model showed a better predictive performance. Dosing simulations support 1000 mg 12-hourly dosing of levetiracetam for patients with CrCL ~60-75 mL/min with higher dose needed for higher values (1500 mg 12-hourly for CrCL ~93-111 mL/min). Dosing regimens should be personalized to the patient's CrCL to maximize the likelihood of therapeutic concentrations.

Nocebo in Biosimilars and Generics in Neurology: A Systematic Review

Background: Nocebo refers to adverse events related to patients’ negative expectations and previous experiences, mediated by several neurobiological pathways within the brain. It is common among neurological patients and affects adherence and treatment outcomes, representing a real clinical challenge.

Methods: We conducted a systematic search based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines in MEDLINE database, using several keywords for studies that can be processed to investigate the magnitude of nocebo in generics and biosimilars used in the most common neurological diseases. The aim was to estimate its size and suggest strategies to minimize its prevalence in clinical trials and practice.

Results: Of a total of 2,606 identified articles, after criteria-based selection, 35 studies were included for analysis. Overall, there was vast heterogeneity across the studies concerning population, study design, and outcomes. Nocebo response could be estimated only in one double-blind randomized trial of generic glatiramer acetate in relapsing remitting multiple sclerosis that included a placebo arm. In this trial, no significant differences observed between the three arms (innovator, bioequivalent, and placebo) in favorable and unfavorable outcomes. In the open-label phase of the trial, an increased withdrawal rate was recorded in patients switched from placebo to bioequivalent (8.4%) that may be related to nocebo. In other open-label and real-world studies evaluating biosimilars or generics for brain disorders, a similar indirect nocebo effect is assuming by several investigators. Also, knowledge gaps between health-care providers and patients exist towards generics and biosimilars.

Conclusions: Despite its presence, the true burden of the nocebo response and effect cannot be accurately estimated in existing studies with generics and biosimilars in neurological diseases. Targeted strategies for clinical trials’ design are needed in order to measure the exact nocebo’s size.

Quality of life after switching to generic levetiracetam - A prospective comparative study

BACKGROUND

Improved quality of life (QoL) is one of the most important objectives in the treatment of epilepsy. Recent prospective, clinical studies proved no significant differences between brand antiepileptic drugs (AEDs) and their generic equivalents in terms of seizure control, pharmacokinetics, or safety. In this study, we focused on possible changes in QoL and adverse events in connection with generic substitution of levetiracetam (LEV).

METHODS

This was a prospective, naturalistic, two-cohort, twin-center study. After a baseline period of 10 weeks, outpatients with epilepsy on stable treatment with Keppra® either continued on this brand (reference group, n = 16) or switched to generic LEV (1A Pharma®) (study group, n = 16) for an eight-week study period. The Quality of Life in Epilepsy Inventory-31 (QOLIE-31) and an adverse events' questionnaire were administered at inclusion, after baseline, and at the end of the study period. The study protocol included a close clinical follow-up with repeated LEV serum concentration measurements and nurse-led outpatient visits.

RESULTS

Clinically relevant improvements in overall QOLIE-31 scores according to minimally important change (MIC) estimates were seen in both groups. QOLIE-31 subscales in both groups showed significantly less worry about seizures at the end of the study compared to scores at inclusion (study group: p = 0.01; reference group: p = 0.02). No significant deterioration in QoL or adverse events were observed following generic substitution. No switchbacks occurred.

CONCLUSIONS

We found reduced seizure worries over time among people with epilepsy allocated to either generic switch or continued treatment with brand LEV. We hypothesize that the nurse-led structured follow-up had an impact on seizure worries and switchback rates because of reduced nocebo effects. Further studies on generic AED substitution, focusing on psychological outcome measures, are warranted to test this supposition.

Is There an Association Between Antiepileptic Drug Use and Dementia Risk? A Case-Control Study

BACKGROUND

Previous research has found a positive association between the use of antiepileptic drugs (AEDs) and dementia. However, there have been some concerns about the generalizability of its findings.

OBJECTIVE

The goal of this case-control study was to analyze the association between AED use and dementia risk in Germany.

METHODS

This study included patients who had received a first dementia diagnosis from one of 1,203 general practitioners or 202 neuropsychiatrists between 2013 and 2017 (index date). Controls without dementia were matched (1:1) to dementia cases by age, gender, physician, diagnosis of mild cognitive impairment, and observation time prior to the index date. Two regression models were used to analyze the association between AED use and dementia risk after adjusting for comorbidities and co-prescribed drugs. AEDs were included as a dichotomous variable in Model 1 (ever versus never use) and as a continuous variable in Model 2 (duration of treatment in years).

RESULTS

A total of 50,575 cases with dementia and 50,575 controls without dementia were included in this study. Model 1 (odds-ratio [OR] = 0.99) and Model 2 (OR = 1.00) showed no significant association between AED use and dementia risk. However, prescriptions for levetiracetam generic brands (Model 1: OR = 1.70; Model 2: OR = 1.36) were associated with an increased dementia risk.

CONCLUSIONS

Overall, AED use was not significantly associated with dementia risk in patients followed by general practitioners and neuropsychiatrists in Germany between 2013 and 2017. Nonetheless, the potential deleterious effects of levetiracetam generic brands on cognition deserve further investigation.