MATERIALS AND METHODS: To examine this hypothesis, in the present study, the associations between CYP3A5 variants (rs776746 and rs1419745) and response to carbamazepine and valproic acid monotherapy in Malaysian epileptic patients were evaluated.
RESULTS: A total of 288 Malaysian epileptic patients were recruited and further reviewed, of whom 63 patients were on carbamazepine monotherapy, and 85 patients were on valproic acid monotherapy. There was no patient with drug hypersensitivity syndrome within the population. Subjects were genotyped by using Sequenom MassARRAY platform. This study found a significant association of CYP3A5 rs776746 with the carbamazepine treatment response in total patients (p = 0.026) and Malay ethnic subgroup (p = 0.006). In addition, a marginal significant association of CYP3A5 rs1419745 with carbamazepine treatment response was reported in the Malays. Similarly, CYP3A5 rs776746 was associated with valproic acid response in total patients (p = 0.037) and Malays (marginal p = 0.05).
CONCLUSION: Our findings suggest that CYP3A5 polymorphisms affect carbamazepine and valproic acid response in Malaysian epileptic patients.
METHODS: The study was an interventional and crossover comparison. Twenty-one patients with TN were administered with LTG in comparison to CBZ. The clinical trials comprised two phases of 40 days each, with an intervening three-day washout period. The final titration in dose for LTG was 400 mg and 1,200 mg for CBZ. Efficacy of the medications involved was determined by visual analog scale (VAS) and verbal rating scale (VRS). Side effects were recorded through marking of the profiles of side effects encountered on administration of LTG and CBZ, together with baseline haematological, hepatic and renal investigations.
RESULTS: Both on VAS and VRS assessments, in terms of proportion of patients, CBZ benefitted 90.5% (19/21) of the patients with pain relief (p 0.05). Meanwhile, LTG inflicted 14% (3/21) of the patients with haematological, hepatic and renal derangements, as compared with 48% (10/21) on CBZ.
CONCLUSION: LTG is generally an effective and safe treatment for management of TN, compared to CBZ.
METHODS: A hybrid model of a decision tree and Markov model was developed to evaluate 3 strategies for treating newly diagnosed epilepsy among adults: (i) CBZ initiation without HLA-B*15:02 screening (current practice); (ii) universal HLA-B*15:02 screening prior to CBZ initiation; and (iii) alternative prescribing without HLA-B*15:02 screening. The model was populated with real-world inputs derived from the Malaysian population. From a societal perspective, base-case analysis and sensitivity analyses estimated the costs and outcomes over a lifetime. Incremental cost-effectiveness ratios were calculated.
RESULTS: In the base-cases analysis, universal HLA-B*15:02 screening yielded the lowest total costs and the highest total quality-adjusted life years (QALYs) gained. Compared with current practice, universal screening was less costly by USD100 and more effective by QALYs increase of 0.1306, while alternative prescribing resulted in 0.1383 QALYs loss at additional costs of USD332. The highest seizure remission rate (56%) was estimated for universal HLA-B*15:02 screening vs. current practice (54%) and alternative prescribing (48%).
CONCLUSION: Our study suggests that universal HLA-B*15:02 screening is a cost-effective intervention in Malaysia. With the demonstrated value of real-world evidence in economic evaluations, more relevant standardization efforts should be emphasized to better inform decision-making.
METHODS: A hybrid decision tree and Markov model was developed to evaluate three strategies for treating newly diagnosed focal epilepsy: CBZ direct therapy, levetiracetam (LEV) direct therapy, and therapy based on HLA-B*15:02 test results. From a societal perspective, base case and sensitivity analyses were carried out over a lifetime.
RESULTS: Direct administration of CBZ appears to have a slightly lower average cost than the HLA-B*15:02 allele screening strategy. The increase in quality-adjusted life year (QALY) in HLA-B*15:02 screening before treatment related to the cost difference reached 0.519 with an incremental cost-effectiveness ratio (ICER) of around USD 984 per unit of QALY acquisition. Direct treatment of LEV increased treatment costs by almost USD 2000 on average compared to the standard CBZ strategy. The increase in QALY is 0.834 in direct levetiracetam treatment, with an ICER of around USD 2230 for each QALY processing.
CONCLUSION: Calculation of the cost-effectiveness of lifetime epilepsy therapy in this study found that the initial screening strategy with the HLA-B*15:02 test was the most cost-effective.