Potential impact of blood cholesterol guidelines on statin treatment in the U.S. population using interrupted time series analysis.

BACKGROUND: The 2013 ACC/AHA Guideline was a paradigm shift in lipid management and identified the four statin-benefit groups. Many have studied the guideline's potential impact, but few have investigated its potential long-term impact on MACE. Furthermore, most studies also ignored the confounding effect from the earlier release of generic atorvastatin in Dec 2011. METHODS: To evaluate the potential (long-term) impact of the 2013 ACC/AHA Guideline release in Nov 2013 in the U.S., we investigated the association of the 2013 ACC/AHA Guideline with the trend changes in 5-Year MACE survival and three other statin-related outcomes (statin use, optimal statin use, and statin adherence) while controlling for generic atorvastatin availability using interrupted time series analysis, called the Chow's test. Specifically, we conducted a retrospective study using U.S. nationwide de-identified claims and electronic health records from Optum Labs Database Warehouse (OLDW) to follow the trends of 5-Year MACE survival and statin-related outcomes among four statin-benefit groups that were identified in the 2013 ACC/AHA Guideline. Then, Chow's test was used to discern trend changes between generic atorvastatin availability and guideline potential impact. RESULTS: 197,021 patients were included (ASCVD: 19,060; High-LDL: 33,907; Diabetes: 138,159; High-ASCVD-Risk: 5,895). After the guideline release, the long-term trend (slope) of 5-Year MACE Survival for the Diabetes group improved significantly (P = 0.002). Optimal statin use for the ASCVD group also showed immediate improvement (intercept) and long-term positive changes (slope) after the release (P < 0.001). Statin uses did not have significant trend changes and statin adherence remained unchanged in all statin-benefit groups. Although no other statistically significant trend changes were found, overall positive trend change or no changes were observed after the 2013 ACC/AHA Guideline release. CONCLUSIONS: The 2013 ACA/AHA Guideline release is associated with trend improvements in the long-term MACE Survival for Diabetes group and optimal statin use for ASCVD group. These significant associations might indicate a potential positive long-term impact of the 2013 ACA/AHA Guideline on better health outcomes for primary prevention groups and an immediate potential impact on statin prescribing behaviors in higher-at-risk groups. However, further investigation is required to confirm the causal effect of the 2013 ACA/AHA Guideline.

Comparative Bleeding Risk of Brand Vs Generic Rivaroxaban in Elderly Inpatients with Atrial Fibrillation.

Objective: Atrial fibrillation (AF) is the most common abnormal heart rhythm in elderly patients. Rivaroxaban has been widely used for stroke prevention. The anticoagulant response to rivaroxaban increases with age, which may make elderly patients susceptible to adverse outcomes resulting from small differences in bioavailability between generic and brand products. Methods: We designed a cohort study of ≥65-year-old inpatients with AF. Sociodemographic and laboratory measures of qualified patients who received brand or generic rivaroxaban for at least 72 hours at the study hospital from January 2021 to June 2023 were collected retrospectively. The primary outcome was the incidence of bleeding. Results: A total of 1008 qualifying patients were included for analysis, with 626 (62.1%) receiving brand rivaroxaban and 382 (37.9%) receiving generic rivaroxaban. After propensity score matching and weighting to account for confounders, the odds ratios comparing brand vs generic rivaroxaban (95% confidence intervals) for the bleeding was 1.15 (0.72-1.82). Results from subgroup analyses of patients with age ≥85, HAS-BLED score ≥ 3, containment of antiplatelet drugs, and female patients were consistent with the primary analysis. Conclusion: It provides evidence regarding the clinical safety outcome of generic rivaroxaban in the elderly AF population that may be particularly susceptible to adverse outcomes resulting from small allowable differences in pharmacokinetics.

A crossover study to evaluate the pharmacokinetics and bioequivalence of hydroxychloroquine tablets in healthy Chinese subjects.

AIMS: Hydroxychloroquine (HCQ) has a high variability and a long half-life in the human body. The purpose of this study was to evaluate the bioequivalence of a generic HCQ tablet (test preparation) versus a brand HCQ tablet (reference preparation) under fasting and fed conditions in a crossover design. MATERIALS AND METHODS: This was an open-label, two-period randomized, single-dose, crossover study in 47 healthy Chinese subjects who were sequentially and randomly allocated either to the fed group (high-fat meal; n = 23) or the fasting group (n = 24). Participants in each group were randomized to the two arms to receive either a single 200-mg dose of the test preparation or a 200-mg dose of the reference preparation. The application of the two preparations in each patient was separated by a 28-day washout period, regarded as sufficiently long to avoid significant interference from residual drug in the body. Whole blood samples were collected over 72 hours after drug administration. RESULTS: A total of 23 subjects completed both the fed and the fasting parts of the trial. There were no significant differences in Cmax, AUC0-72h, and T1/2 between the test and reference preparation (p < 0.05). Food had no significant effect on Cmax and T1/2 (p < 0.05), but AUC0-72h values were significantly reduced under fed condition compared to fasting condition (p < 0.05). The 90% confidence intervals (CIs) for the geometric mean ratios (GMRs) of Cmax and AUC0-72h were 0.84 - 1.05 and 0.89 - 0.98 in the fed study, and 0.97 - 1.07 and 0.97 - 1.05 in the fasting study, respectively. The carryover effect due to non-zero blood concentrations resulted in higher AUC0-72h values in the second period for both test and reference formulations and had no effect on the statistical results. No serious adverse events were reported. CONCLUSION: The investigation demonstrated that the test and reference preparations are bioequivalent and well tolerated under both fasting and fed conditions in healthy Chinese subjects.

Severe cutaneous adverse reaction to drug excipient following brand-to-generic switch of levetiracetam.

PURPOSE: Levetiracetam is an antiepileptic drug known for its high tolerability, and severe adverse drug reactions are rare. We report the case of a severe cutaneous adverse drug reaction in a patient who was switched from brand-name to generic levetiracetam. SUMMARY: A 29-year-old woman undergoing contrast-enhanced computed tomography developed lesions over her trunk starting 6 hours after imaging. Although initially diagnosed as an allergy to the radiocontrast agent, the condition progressively worsened into toxic epidermal necrolysis-drug reaction with eosinophilia and systemic symptoms overlap syndrome, despite adequate hydration and treatment. Investigation of the patient's medications revealed that she had been switched from brand-name to generic levetiracetam a week before the onset of symptoms. Levetiracetam was immediately discontinued, with the patient recovering after 2 weeks of intensive care. Adverse drug reaction analysis identified excipients in generic levetiracetam as the likely cause of the severe reaction. CONCLUSION: This is the first reported case of severe cutaneous drug allergy after a brand-to-generic switch for levetiracetam. Brand-to-generic switches of medications can potentially cause severe allergic reactions due to differences in excipients.

Biopharmaceutics Risk Assessment-Connecting Critical Bioavailability Attributes with In Vitro, In Vivo Properties and Physiologically Based Biopharmaceutics Modeling to Enable Generic Regulatory Submissions.

Quality risk assessment following ICH Q9 principles is an important activity to ensure optimal clinical efficacy and safety of a drug product. Typically, risk assessment is focused on product performance wherein critical material attributes, formulation variables, and process parameters are evaluated from a manufacturing perspective. Extending ICH Q9 principles to biopharmaceutics risk assessment to identify factors that can impact in vivo performance is an upcoming area. This is evident by recent regulatory trends wherein a new term critical bioavailability attributes (CBA) has been coined to identify such factors. Although significant work has been performed for biopharmaceutics risk assessment for new molecules, there is a need for harmonized biopharmaceutics risk assessment workflow for generic submissions. In this manuscript, we attempted to provide a framework for performing biopharmaceutics risk assessment for generic regulatory submissions. A detailed workflow for performing biopharmaceutics risk assessment includes identification of initial CBA (iCBA), their confirmatory evaluation followed by definition of the control strategy. Tools for biopharmaceutics risk assessment, i.e., bio-discriminatory dissolution method and physiologically based biopharmaceutics modeling (PBBM) were discussed from a practical perspective. Furthermore, a case study for CBA evaluation using PBBM modeling for an extended-release product for regulatory submission has been described using the proposed workflow. Finally, future directions of integrating CBA evaluation, biopharmaceutics risk assessment to the FDA Knowledge Aided Structured Assessment (KASA) initiative, the necessity of risk assessment templates, and knowledge sharing between industry and academia are discussed. Overall, the work described in this manuscript can facilitate and provide guidance for biopharmaceutics risk assessment for generic submissions.

Side Effects of Antihypertensives Induced by Switching to Different Generic Medications: Case Reports.

Generic medication is a product that contains the same active substance and pharmaceutical characteristics as brand-name medications. Generic medications are cost-effective and comparable to brand-name medications in terms of clinical endpoints. However, the use of generic medications instead of brand-name medications is a debatable issue among patients and healthcare providers. Two patients with essential hypertension experienced side effects after switching to different generic antihypertensives (one generic medication to another generic medication). Adverse drug reactions, including, hypersensitivity, side effects, and intolerance, should be identified through present and past medical history and clinical characteristics. The adverse drug reactions in both patients were more likely to be side effects of the medications after switching to different generic antihypertensives produced by different companies (patient 1: enalapril and patient 2: amlodipine). The side effects were possibly caused by the different inactive ingredients or excipients. These two case reports emphasise the importance of monitoring adverse drug reactions throughout the course of treatment and communicating with patients prior to switching to a new generic medication.

Bioequivalence Study of Ezetimibe Tablets After a Single Oral Dose of 10 mg in Healthy Japanese Subjects Under Fasting Conditions.

This study compared the pharmacokinetic and safety profiles between a new generic and a branded reference product of 10-mg ezetimibe (EZE) tablets in 24 healthy Japanese male volunteers under fasting conditions, obtaining sufficient evidence for the marketing approval of the new generic product. The bioequivalence study was conducted with an open-label, 2 × 2, single-dose, crossover design in which the test and reference products were administered to volunteers after fasting for ≥10 hours. Blood samples were collected 24 times before to 72 hours after the administration of the investigational drug. We evaluated the peak drug concentration and the area under the plasma concentration-time curve up to the last measured concentration of EZE, EZEG, and total EZE (EZE + ezetimibe glucuronide [EZEG]). The 90% confidence intervals of the geometric mean ratios for peak drug concentration and area under the plasma concentration-time curve up to the last measured concentration of the test and reference products fell within the bioequivalence limits of 0.80 to 1.25 for EZE, EZEG, and total EZE. The test and reference products were well tolerated, and no adverse events occurred during the study. The test product was bioequivalent to the reference product.

The consequences of switching from Gilenya® to generics for fingolimod.

BACKGROUND: On May 2017, two generic drugs for fingolimod were introduced into the market in Israel, and most MS patients treated with Gilenya® (Novartis) were switched to fingolimod (Teva), or to Finolim (Rafa). In this study we analyzed the consequences of switching to generic fingolimod in a single MS center. METHODS: Study population included relapsing MS patients who were treated with Gilenya® for at least two year before May 2017, switched to generic fingolimod and remained on treatment for at least 2 years thereafter. Data before and after the switch were compared. RESULTS: Twenty-seven patients fulfilled the inclusion criteria (F = 20, RRMS=20, SPMS=7, average age 49±11.4 years, average disease duration=16.6 ± 7.6 years). Seventeen patients had to be switched back to the original Gilenya® due to intolerable new or worsening clinical adverse events (n = 9), clinical relapse (n = 1), clinical relapse with adverse events (n = 3), elevation of liver enzymes > X3 ULN (n = 3) and elevation of amylase (n = 1). Expanded Disability Status Scale (EDSS) score increased in 4 patients during the year before the switch, and in 12 patients during the year of treatment with generic fingolimod (p = 0.036). CONCLUSION: The tolerability, retention rate and probably efficacy of generic fingolimod seems to be lower than the original Gilenya®.

Factors Affecting Patients' Acceptance of Switching to Biosimilars Are Disease-Dependent: A Cross-Sectional Study.

Biosimilars (BS) are promoted worldwide because of the high cost of biologics. However, patients are apprehensive about switching to BS. For some diseases, several factors, which may be disease-dependent, influence patients' acceptance of switching to BS. Herein, we evaluated whether factors influencing acceptance for switching were disease-dependent among Japanese patients with different diseases. This cross-sectional study involved pharmacists' interviews with patients who used or planned to use biologics. Demographic and clinical characteristics were retrospectively investigated using the patients' medical records. Multivariate logistic regression showed that switch refusal was associated with a history of adverse reactions to biologics (odds ratio [95% confidence interval (CI)] = 3.38 [1.35-8.44]), history of complaints related to disease activity (3.57 [1.53-8.32]), and unacceptability of generic drugs (7.62 [2.70-21.60]). Subgroup analyses suggested that the unacceptability of generic drugs was a common factor, regardless of the disease. Concomitantly, histories of adverse reactions to biologics and complaints related to disease activity were disease-dependent factors. Healthcare professionals should help patients in selecting BS, considering these factors according to the disease.

Do generic drugs cause hypersensitivity?

Generic drugs may differ from brand-name drugs in nature and quantity of excipients. Hypersensitivity to generic drugs is a subject of growing importance given their key role in healthcare spending policies, however, a review of published data highlighted that relevant data is sparse. No scientific rationale has emerged for labelling patients allergic to all generic drugs, and hypersensitivity to generic drugs may rather be explored on a case-by-case basis. In the case of hypersensitivity without any change in medication, it is advisable to check for a switch from a brand-name to a generic drug, and if hypersensitivity to a generic drug is suspected, its composition must be checked.

Comparative Study of 2 Extended-Release Tacrolimus Formulations in Kidney Transplantation.

BACKGROUND: During the 1900s, tacrolimus became the mainstay immunosuppressive agent to prevent rejection after kidney transplant. Subsequently, an extended-release tacrolimus (ER-Tac) formulation was developed to improve adherence, and its generic version has been marketed over the last years. This study examines the differences in efficacy and safety between the generic ER-Tac (Conferoport) and the reference brand-name drug (Advagraf). METHODS: Prospective, randomized and parallel single-center study (May 2020 to June 2021) with 52 kidney transplant recipients who were randomly assigned to 1 of the following groups: study group (Conferoport, n = 31) and control group (Advagraf, n = 21). The variables of interest were collected and analyzed to compare tacrolimus efficacy and safety between them. Demographic characteristics of the patients and clinical donor data were homogeneous in both groups (P > .05). RESULTS: No statistically significant differences were found among treatments regarding dosage used, levels, creatinine, and proteinuria (P > .05), with these variables presenting a downward trend during follow-up and, consequently, the improvement of graft function. Analyses also revealed the absence of differences concerning the incidence of acute rejection and intrapatient variability (coefficient of variation) throughout the first year of evolution between both formulations (P > .05). A total of 5 graft losses occurred, 2 resulting from patient death. CONCLUSIONS: In our experience, we found no significant differences between the measured parameters in relation to the efficacy and safety profile of both drugs, with generic ER-Tac being an alternative comparable with the reference brand-name ER-Tac.

Pharmacokinetics, Bioequivalence, and Safety Studies of a Generic Selective Tyrosine Kinase Inhibitor Nilotinib Capsule Versus a Branded Product in Healthy Chinese Volunteers.

Nilotinib, a second-generation tyrosine kinase inhibitor (TKI), has been approved in the United States and Europe as a treatment for patients with newly diagnosed chronic myeloid leukemia (CML)-chronic phase (CP) and patients with CML-CP or chronic myeloid leukemia-accelerated phase (CML-AP) who are resistant or intolerant to imatinib (a first-generation TKI). This study compared the bioequivalence and safety of the test nilotinib capsule and reference nilotinib capsule (Tasigna, Novartis) in healthy Chinese volunteers under fasting conditions for marketing authorization in China. The results of the study are reported for the first time. This was a single-dose, randomized, open-label, two-period, and cross-over study. Thirty healthy volunteers were randomly assigned to receive a single dose of a 200-mg test or reference capsule under fasting conditions in each period with a 10-day washout. Plasma samples were analyzed with liquid chromatography-tandem mass spectrometry. Pharmacokinetic parameters were calculated with WinNonlin software. The geometric mean ratio and the corresponding 90% confidence intervals of Cmax , AUC0-t , and AUC0-∞ for nilotinib between the two fixed-dose combination formulations were within the bioequivalence acceptance range of 80%-125%, therefore the generic and branded formulations were bioequivalent in healthy Chinese volunteers.

Efficacy and Safety of Generic Dasatinib in Patients With Newly Diagnosed Chronic Myeloid Leukemia in Chronic Phase: A Multicenter Prospective Study in China.

BACKGROUND: Brand-name dasatinib was approved for newly diagnosed chronic myeloid leukemia-chronic phase (CML-CP) patients due to its deeper and faster molecular response than imatinib. Generics, as the alternative, low-cost forms, are much in demand. This study aimed to evaluate the efficacy and safety of generic dasatinib (Yinishu) as a first-line treatment in CML-CP. MATERIALS AND METHODS: This was a prospective, multicenter, single-arm study from May 2016 to October 2018 with a 2-year follow-up analysis. All patients were given 100 mg/d (initial dose) of the generic dasatinib once a day. The primary endpoint was the major molecular response (MMR) calculated based on the BCR-ABL1 gene mutation rate of ≤ .1% at 12 months. RESULTS: Among 55 patients in CP observed for at least 3 months, 80.4% achieved MMR at 12 months. The cumulative MR4.5 was 58.2% by 24 months. Responses occurred rapidly, with 69.1% of patients achieving complete cytogenetic response (CCyR) by 3 months and 70.9% achieving CCyR by 6 months. The estimated 2-year PFS and OS were both 96%, with a median follow-up time of 24 months. Grade 3 neutropenia occurred in 8.5% of patients, and thrombocytopenia occurred in 11.9% of patients. Nonhematologic toxicity was usually mild and manageable. Pleural effusion occurred in 20.3% of patients, and only 1 patient (1.7%) had a grade 3 pleural effusion. No grade 4 adverse events were observed. CONCLUSION: Generic dasatinib is an effective option for newly diagnosed CML-CP patients, producing an MMR early in a greater number of patients during their therapy.

Analysis of antiviral efficacy after switching from brand to generic entecavir in patients with treatment-naïve chronic hepatitis B.

BACKGROUND/AIMS: Entecavir (ETV) can suppress chronic hepatitis B (CHB) virus replication as a standard of treatment drugs. For the treatment of CHB, affordable generic drugs may be more widely used in developing and undeveloped countries. However, there is little real-world data regarding the clinical efficacy of switching from entecavir-brand-name drugs (ETV-Brand) to entecavir generic drugs (ETV-Generic) with 0.5 mg once daily. The aim of the study was to evaluate the antiviral activity and safety of ETV-Generic in comparison to ETV-Brand in CHB-patients. METHODS: In this single-center, retrospective, 175 treatment-naïve-CHB-patients were assigned to receive 0.5 mg of ETV-Brand per day for a least 2 years and then switched to ETV-Generic for 6 months for analysis. The primary efficacy endpoint was a sustained virological response in comparison of the rate of undetectable serum Hepatitis B deoxyribonucleic acid (HBV DNA) as the sustained virologic response at baseline and 6 months after switching. Secondary efficacy endpoints were the comparison of the alanine aminotransferase (ALT) levels between before and after switching and ALT normalization. Renal safety consideration was reported on changing the estimated glomerular filtration rate. RESULTS: From baseline to 6 months, the rate of undetectable HBV DNA and ALT levels remained stable as compared ETV-Brand period with ETV-Generic for 6 months. The rate of undetectable HBV DNA were 81.1%in ETV-Brand versus 88.0%in ETV-Generic (p = 0.05 CI 0.1-13.5%). ALT levels were 27.2 IU/L (CI 24.8-29.6 IU/L) in ETV-Brand versus 26.2 IU/L (CI 24.0-28.4 IU/L) in ETV-Generic (p = 0.55). Both endpoints were not significantly different between ETV-Brand and ETV-Generic treatments. Kidney function did not significantly differ from ETV-Brand (80.8, interquartile range [IQR]: 66.6-95.3 mL/min/1.73 m2) to ETV-Generic treatment period (80.3, IQR: 65.6-93.5 mL/min/1.73 m2). CONCLUSION: In treatment-naïve CHB-patients, the efficacy and safety profiles of switching from ETV-Brand to ETV-Generic showed no difference. Concluding the ETV-Generic comes to exciting virologic responses and rare adverse events.

Comparative effectiveness of generic nifedipine versus Adalat long-acting nifedipine for hypertension treatment: A multi-institutional cohort study.

This retrospective multi-institutional database analysis aimed to evaluate the blood-pressure-lowering efficacy and clinical outcomes of a generic versus brand-name nifedipine for hypertension management. A total of 12 693 patients who were prescribed a generic or brand-name nifedipine between January 1, 2011, and December 31, 2018, were identified from the Chang Gung Research Database of Chang Gung Memorial Hospitals, Taiwan. Among them, 2112 (21.4%) were prescribed generic nifedipine. After propensity score matching, both the generic and brand-name groups consisted of 2102 patients. At a mean follow-up of 3 years, the changes in office systolic (p for interaction = .791) and diastolic blood pressure (p for interaction = .689) did not differ significantly between the patients who received the generic and the brand-name nifedipine. There was no significant difference between the two study groups regarding the composite of all-cause mortality, acute myocardial infarction, stroke, coronary revascularization, or hospitalization for heart failure (hazard ratio 0.98, 95% confidence interval 0.85-1.13; p = .774). In conclusion, the generic nifedipine was comparable to its brand-name counterpart regarding office blood pressure reduction and the composite cardiovascular outcome for the treatment of patients with hypertension.

Understanding treatment patterns and patient-reported outcomes associated with the use of authorized generics and corresponding independent generics across multiple therapeutic areas.

OBJECTIVES: To assess patient characteristics, treatment patterns, and patient-reported outcomes (PROs) associated with authorized generics (AGs) and independent generics (IGs) use. METHODS: Prescription claims and National Health and Wellness Survey (NHWS) data were linked. Adults with billable national drug code (AG or IG), NHWS completion from June 2015 to July 2019, AG or IG on-hand at NHWS completion, and continuous insurance eligibility in 12 months pre- and post-NHWS completion were included. To be included, all unique medication formulations had to have at least one AG and one IG observation. PRO index date was NHWS completion; claims index date was defined as the first prescription claim identified during the 180-day period prior to NHWS completion for the same active ingredient and formulation type that was on-hand at NHWS completion. RESULTS: Patients (N = 20,229; 17.2% AG users) in six therapeutic areas (attention deficit-hyperactivity disorder [ADHD], antidepressants, beta blockers [BBs], calcium channel blockers [CCBs], statins, and thyroid) were included. Generally, AG (vs. IG) users were younger and differed in regional access and insurance type (all, p < .05). In multivariable analysis, significant differences were observed for presenteeism and overall work impairment (BBs), healthcare provider visits (BBs), and indirect costs (thyroid) (all, p < .05). AG and IG users differed in persistence (ADHD and statins; both, p < .05) and switch (BBs and CCBs; both, p < .01) rates. CONCLUSIONS: PRO differences were often small in magnitude and varied by therapeutic area. The impact of switching should consider observed PRO differences, patient preferences, and market availability of AG and IG alternatives.

Therapeutic Basis of Generic Substitution of Antiseizure Medications.

More than thirty antiseizure medications (ASMs) are available for treating epilepsy. ASMs differ in their potency and efficacy in controlling seizures by acting on diverse targets in the brain, often with variable pharmacokinetics. Moreover, nearly 30% of people with epilepsy have drug-resistant or intractable seizures. Generic substitution of ASMs is a complex issue. It is thought that frequent generic substitution in people with epilepsy may cause problems because the U.S. Food and Drug Administration (FDA) rules allow too much variability across products. The standard bioequivalence range (80% to 125%) appears too broad for many ASMs, especially those exhibiting little separation between therapeutic and toxic levels. Hence, sub-therapeutic concentration may lead to therapeutic failure with seizure recurrence, which could be life threatening. A supra-therapeutic level could result in adverse effects or compliance issues. There are reported issues with generic substitutions of phenytoin, topiramate, levetiracetam, carbamazepine, and lamotrigine. There is discussion in the epilepsy community about additional guidelines, including designation of generic ASMs as Narrow Therapeutic Index (NTI) drugs and how patient education plays a role in generic substitution. Overall, based on the published evidence on specific generic ASMs, FDA bioequivalence standards are not the cause of problems with generic ASM substitution. Rather, it is imperative that physicians and pharmacists provide adequate patient education on what to expect when switching to generic ASMs, including changes in medication shape and color. Another suggestion would be to consider that all ASMs be considered for inclusion in NTI class to prevent the clinical outcome issues associated with generic ASM switching. SIGNIFICANCE STATEMENT: There are critical aspects to consider when switching from a brand name antiseizure medication (ASM) when a generic becomes available or switching between generics. Generic ASMs are interchanged with little consideration of differences in therapeutic equivalence and other clinical factors. This article describes key issues on generic substitution of ASMs and highlights critical pharmacotherapeutic issues associated with generic ASMs.

Comparing real-life carbamazepine exposure between innovator and generic formulation.

BACKGROUND: Carbamazepine is an anticonvulsant largely used in the treatment of epilepsy. The use of generic antiepileptic drugs (AEDs) is controversial because of the eventual possibility to loss seizures control. The aim of our study was to compare the concentration over dose ratio of two products containing carbamazepine, the innovator (Tégrétol®-NOVARTIS) and the generic (Taver®-MEDOCHEMIE). METHODS: It is a retrospective study (2009-2016) including 32 patients treated with carbamazepine. Patients were treated initially by innovator then switched to generic or vice versa. All patients have at least one level of carbamazepine plasma concentration (C0) with the innovator or the generic formulation. Monitoring of carabamazepine was made using immunoassay method (ARCHITECT-ABOTT®). RESULTS: The mean age of our patients was 28.4 years and ranged from 2 to 55 years. The sex ratio M/F was 1.46. The mean ratio C0/dose for the innovator group was 0.723 (min/max: 0.017/1.73), and the mean ratio C0/dose for the generic group was also 0.607 (min/max: 0.064/1.68). There was no statistically significant difference between both groups (P=0.16). CONCLUSION: Our results confirm the difference between the innovator and the generic formulation of carbamazepine. So, switching from innovator to generic seems to be safe and exposure to carbamazepine remains the same.

Quality control concerns in relation to lamotrigine and their impact.

OBJECTIVE: To pursue explanations for compromised efficacy and induction of side-effects in some generic brands of lamotrigine distributed in Australia. METHOD: Bioassays of the non-generic and five generic lamotrigine tablets were undertaken (also after exposure to heat and cold), as well as assays of two generic drugs generating concerning side-effects in two patients, while enquiries were made of manufacturing companies. RESULTS: Mass spectrometry of the six tested products showed comparable properties and no compromising when those tablets were heated and cooled, while analyses of the products taken by the two patients reporting significant side-effects showed an increase in the peak area lamotrigine concentration. CONCLUSIONS: We failed to identify any intrinsically compromised product in our comparison analyses of the six preparations. We consider alternate explanations for an issue leading to widespread international reporting of distinct side-effects and deaths following brand switching, with analyses of the two problematic preparations supporting a 'faulty' batch explanation.