--- title: "Azetukalner (XEN1101) in Focal onset seizures: cost-effectiveness analyses and utility weights" description: "Published cost-effectiveness analyses and health-state utility weights for Azetukalner (XEN1101) in Focal onset seizures, each value quoted from the article: 15 cost-effectiveness analyses and 9 studies reporting utility weights. Analyses: Cenobamate versus brivaracetam, eslicarbazepine, lacosamide, and perampanel in drug-resistant focal seizures, United Kingdom: Laskier et al. (2023); Cenobamate versus brivaracetam, perampanel, eslicarbazepine acetate, and lacosamide in adults with drug-resistant focal-onset seizures, Spain: Calleja et al. (2022); Add-on pregabalin versus no add-on therapy in refractory partial epilepsy, United States: Vera-Llonch et al. (2008); Adjunctive brivaracetam versus adjunctive perampanel in focal onset seizures, Finland: Väätäinen et al. (2020); 11 further articles. Utility weights: Utility weights for seizure control states and refractory seizures with drug-related side effects, refractory epilepsy: Messori et al. (1998); Utility weights by annual seizure frequency and seizure freedom, partial-onset seizures: Zhang et al. (2021); Utility weights for seizure freedom and seizure reduction above and below 50%, focal onset seizures: Väätäinen et al. (2020); Utility weights for seizure freedom, response, nonresponse, withdrawal, and adverse events, refractory focal epilepsy: Bolin et al. (2013); 5 further articles. Every value is a verbatim quote from the primary article it is shown with." canonical: "https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures/cost-effectiveness-analyses" published: "2026-10-22T07:49:06-04:00" modified: "2026-10-22T07:49:06-04:00" --- # Azetukalner (XEN1101) in Focal onset seizures: cost-effectiveness analyses and utility weights Published cost-effectiveness analyses and health-state utility weights that a model of this product could cite, adapt, or compare against, grouped by how each article relates to the product and its indication. Every value is quoted from the article it cites, and section 3 lists the searches that found the articles. ## Overview | Item | Detail | | --- | --- | | Literature searched | Tufts Medical Center Cost-Effectiveness Analysis Registry, searched October 21, 2026; the queries are listed in section 3. | | Cost-effectiveness analyses | 15 | | Studies reporting utility weights | 9 | ## 1 Cost-effectiveness analyses ### 1.1 Analyses of Azetukalner (XEN1101) No evidence found. ### 1.2 Treatments for the same indication #### Cenobamate versus brivaracetam, eslicarbazepine, lacosamide, and perampanel in drug-resistant focal seizures, United Kingdom: Laskier et al. (2023) Relevance: Evaluates adjunctive cenobamate against brivaracetam, eslicarbazepine, lacosamide, and perampanel for focal seizures in drug-resistant epilepsy in the United Kingdom, the analysis section 4.1 of the report quotes and the adjunctive agents section 2 lists as current treatment options. > “This study was undertaken to estimate the cost-effectiveness of add-on cenobamate in the UK when used to treat drug-resistant focal seizures in adults who are not adequately controlled with at least two prior antiseizure medications, including at least one used adjunctively.” > “We estimated the cost per quality-adjusted life-year (QALY) for cenobamate compared to brivaracetam, eslicarbazepine, lacosamide, and perampanel in the UK National Health Service over a lifetime time horizon.” > “We used a Markov cohort structure to determine response to treatment, using pooled data from three long-term studies of cenobamate.” > “Utility data were based on Short-Form six-dimension form utility.” > “Discounting was applied at 3.5% per annum as per National Institute for Health and Care Excellence guidance.” > “In the base case, cenobamate led to cost savings of £51 967 (compared to brivaracetam), £21 080 (compared to eslicarbazepine), £33 619 (compared to lacosamide), and £28 296 (compared to perampanel) and increased QALYs of 1.047 (compared to brivaracetam), 0.598 (compared to eslicarbazepine), 0.776 (compared to lacosamide), and 0.703 (compared to perampanel) per individual over a lifetime time horizon.” > “Cenobamate also dominated the four drugs across most sensitivity analyses.” Source: [Laskier et al. (2023)](https://pubmed.ncbi.nlm.nih.gov/36625423/) #### Cenobamate versus brivaracetam, perampanel, eslicarbazepine acetate, and lacosamide in adults with drug-resistant focal-onset seizures, Spain: Calleja et al. (2022) Relevance: Estimates the economically justifiable price of adjunctive cenobamate against brivaracetam, eslicarbazepine, lacosamide, and perampanel for focal-onset seizures in adults with drug-resistant epilepsy in Spain, an analysis section 4.1 of the report quotes. Access: Free full text > “A simulation Markov model was developed using Microsoft Excel® for the cost-effectiveness (CE) analysis of cenobamate versus the above mentioned third-generation ASMs.” > “The analysis was performed from the Spanish healthcare system perspective. A 60-year time horizon was employed as it comprehensively captures the expected costs and health outcomes of patients over their remaining lifetime.” > “A 3.5% annual discount was applied both for costs and for health outcomes in line with Spanish guidelines” > “Based on the WTP threshold of €21,000/QALY, an EJP of €7.30 was calculated. Over the lifetime period, at this EJP, treatment with cenobamate was associated with a total cost of €83,891 and 11.585 QALYs.” > “In comparison with third-generation ASMs, cenobamate resulted in differential cost versus alternatives ranging from €6,715 for eslicarbazepine acetate to €-4,251 for brivaracetam and incremental QALYs ranging from 0.706 for brivaracetam to 0.320 for eslicarbazepine acetate.” > “At an EJP of €7.30, cenobamate is not only cost-effective compared to all third-generation therapeutic alternatives but also dominant (cost-saving) compared to brivaracetam. The analysis resulted in ICER values of 21,000 vs. eslicarbazepine acetate, 8,389 vs. perampanel, 2,202 vs. lacosamide and −6,022 vs brivaracetam.” > “At a daily price of €5.45, cenobamate becomes dominant over all treatment alternatives producing cost-savings for the national health system (NHS).” Source: [Calleja et al. (2022)](https://doi.org/10.1080/14737167.2022.2107507) #### Add-on pregabalin versus no add-on therapy in refractory partial epilepsy, United States: Vera-Llonch et al. (2008) Relevance: Evaluates add-on pregabalin, an alpha-2-delta ligand listed in section 2, in refractory partial epilepsy in the United States, the population of adults on background antiseizure medications enrolled in the X-TOLE trials. > “We developed a model to estimate clinical and economic outcomes over 1 year in a hypothetical cohort of patients with refractory partial epilepsy assumed alternatively to receive add-on therapy with pregabalin (300 mg/day) or no add-on therapy.” > “For each patient in the model, we estimated the occurrence of seizure and side effects, using techniques of stochastic simulation.” > “Cost-effectiveness was assessed alternatively in terms of incremental cost per SF day gained and incremental cost per QALY gained.” > “Add-on therapy with pregabalin was estimated to result in an average gain of 23.8 SF days over one year; the estimated additional cost of therapy was $678.” > “Incremental cost (mean, 95% CI) per SF day gained was $28.45 ($27.25, $29.44); corresponding estimates of incremental cost per QALY gained were $52,893 ($49,249, $56,983).” Source: [Vera-Llonch et al. (2008)](https://pubmed.ncbi.nlm.nih.gov/17822431/) #### Adjunctive brivaracetam versus adjunctive perampanel in focal onset seizures, Finland: Väätäinen et al. (2020) Relevance: Evaluates adjunctive brivaracetam, an SV2A ligand listed in section 2, against perampanel for focal onset seizures in Finland. > “The economic value of brivaracetam was assessed with cost-utility analysis using a discrete event simulation model (DESM) developed for this purpose” > “only direct health care costs and travel were included, and a third-party payer perspective was applied.” > “A 5-year time horizon was considered sufficient to capture the relevant clinical pathway.” > “A discount rate of 3% per year was used because the time horizon exceeded 1 year” > “In the modeled base case comparison, patients had either brivaracetam or perampanel added as a third concomitant AED to their existing treatment of two concurrent AEDs” > “During the modeled 5-year time horizon, treatment with brivaracetam resulted in an average additional QALY gain of 0.059 (+ 1.6%) compared with perampanel, with an average additional cost of €318 (total + 1.1%, on average €64 per year) per patient” > “Consequently, the resulting ICER, or the average cost of one additional QALY gained with brivaracetam in comparison with perampanel, was only €5345 per QALY gained in the base case simulation.” > “Brivaracetam had 71% and 80% probability of cost-effectiveness compared with perampanel at the willingness to pay of €25,358 and €38,036 per QALY gained, respectively” Source: [Väätäinen et al. (2020)](https://pmc.ncbi.nlm.nih.gov/articles/PMC6979440/) #### Adjunctive brivaracetam versus eslicarbazepine, lacosamide, perampanel, and zonisamide in epilepsy, Spain: Barrachina-Martinez et al. (2021) Relevance: Evaluates adjunctive brivaracetam, an SV2A ligand listed in section 2, against third-generation antiepileptic drugs used as standard care in epilepsy in Spain. Access: Not open access Not quoted: The results for eslicarbazepine and perampanel are reported in the full text, which this page does not quote. > “This study aims to assess the cost utility of Brivaracetam compared with the third-generation anti-epileptic drugs used as standard care.” > “The treatment pathway of a hypothetical cohort over a period of 2 years was simulated using the Markov model.” > “A probabilistic sensitivity analysis was performed using a Monte Carlo simulation.” > “Brivaracetam was shown to be the dominant alternative, with Incremental Cost Utility Ratio (ICUR) values from -11,318 for Lacosamide to -128,482 for Zonisamide.” > “The probabilistic sensitivity analysis validates these results.” Source: [Barrachina-Martinez et al. (2021)](https://pubmed.ncbi.nlm.nih.gov/33074031/) #### Adjunctive perampanel versus lacosamide in partial-onset seizures, China: Zhang et al. (2021) Relevance: Evaluates adjunctive perampanel, an AMPA receptor antagonist listed in section 2, against lacosamide for partial-onset seizures in China, with a model structured by seizure frequency. > “This study selected a health system perspective.” > “A Markov model was established to simulate the lifelong transition of different response levels and calculate the number of seizures in Chinese patients.” > “The cycle period of the model was set to 4 months (consistent with the medication regimen).” > “A lifetime horizon was adopted.” > “Health outcomes and costs were discounted at an annual discount rate of 5%.” > “Compared with LCM 400 mg/day, PER 8 mg/day reduces the number of seizures per capita by 141 times, with an incremental LY of 0.061, an incremental QALY of 0.054, and a direct medical cost saving of $2,390.” > “Compared with LCM200 mg/day, PER 4 mg/day reduces the number of seizures per capita by 72 times, with an incremental LY of 0.012, an incremental QALY of 0.010, and a cost savings of $860.” > “However, compared with PER 4 mg/day, LCM 200 mg/day results in an incremental QALY of 0.005 and an incremental cost of $554.” Source: [Zhang et al. (2021)](https://pmc.ncbi.nlm.nih.gov/articles/PMC8290415/) #### Lacosamide added to standard antiepileptic drug therapy versus standard therapy alone in refractory focal epilepsy, Belgium: Simoens et al. (2012) Relevance: Evaluates adjunctive lacosamide, a sodium channel blocker listed in section 2, added to standard antiseizure therapy in refractory focal epilepsy in Belgium. > “This study aims to assess the cost effectiveness of standard anti-epileptic drug therapy plus lacosamide 300 mg/day compared with standard therapy alone from the perspective of the Belgian healthcare payer.” > “The treatment pathway of a hypothetical cohort of 1000 patients over 2 years was simulated using a decision tree.” > “The price year was 2008.” > “Over a 24-month period, standard anti-epileptic drug therapy plus lacosamide led to a reduction of seven seizures, an increase of 0.038 quality-adjusted life-years and a cost decrease of &U20AC;3619 per patient compared with standard therapy alone.” > “Using a willingness to pay of &U20AC;30 000 per quality-adjusted life-year, the net monetary benefit of standard anti-epileptic drug therapy plus lacosamide amounted to &U20AC;4754.” > “The probability of standard anti-epileptic drug therapy plus lacosamide being cost effective was 97.3%, 99.8%, 99.9% and 100% at 6, 12 , 18 and 24 months, respectively.” Source: [Simoens et al. (2012)](https://pubmed.ncbi.nlm.nih.gov/22452528/) #### Adjunctive lacosamide versus no adjunctive treatment in uncontrolled partial-onset seizures, Sweden: Bolin et al. (2010) Relevance: Evaluates adjunctive lacosamide, a sodium channel blocker listed in section 2, against no adjunctive treatment for uncontrolled partial-onset seizures in Sweden. > “To calculate cost per additional quality-adjusted life-year (QALY) for lacosamide as adjunctive treatment for patients with uncontrolled partial-onset seizures as compared to no adjunctive treatment.” > “A decision-tree simulation model was constructed to calculate the number of seizures and health-care utilization for treated and untreated with lacosamide, respectively.” > “Prices from 2007 were used for all costs.” > “All results were calculated for a 24-, 18-, 12- and 6-months follow-up.” > “The cost per additional QALY was estimated to euro 27,641 (24 months).” > “Using a willingness-to-pay threshold for a QALY of euro 50,000 the net marginal value of using lacosamide was estimated to about euro 850,000 per 1000 patients.” Source: [Bolin et al. (2010)](https://pubmed.ncbi.nlm.nih.gov/20199516/) #### Adjunctive antiepileptic drugs versus placebo in adults with refractory focal seizures, United Kingdom: Nunes et al. (2013) Relevance: Compares all licensed adjunctive antiepileptic drugs, including lacosamide, eslicarbazepine, levetiracetam, lamotrigine, and pregabalin, with placebo for refractory focal seizures in adults from a UK National Health Service perspective. > “An original economic model was developed to compare all licensed AEDs, including lacosamide, used as adjunctive therapy in adults with refractory focal seizures.” > “The analysis took a UK National Health Service perspective, with costs expressed in 2009–2010 pound sterling.” > “A 15-year time horizon was considered relevant and sufficiently long enough to capture the important costs and consequences of treatment.” > “The effectiveness of different AEDs was based on clinical evidence from pair-wise meta-analyses of placebo-controlled trials.” > “Results for lacosamide are summarized in Table 2 and indicate that as adjunctive therapy, it is associated with increased costs (£2849) and improved health outcomes (0.043 more QALYs) compared with continuation of existing therapy alone (placebo).” > “The incremental cost-effectiveness ratio for lacosamide compared with placebo is £66,256 per QALY gained, placing it beyond the NICE-willingness-to-pay threshold of £20,000.” Source: [Nunes et al. (2013)](https://pmc.ncbi.nlm.nih.gov/articles/PMC3626368/) | Adjunctive antiepileptic drug | Total cost (£) | Total QALYs | ICER versus placebo (£/QALY) | | --- | --- | --- | --- | | “Gabapentin” | “9394” | “8.255” | “8034” | | “Lamotrigine” | “9431” | “8.264” | “7507” | | “Oxcarbazepine” | “10,564” | “8.314” | “13,983” | | “Topiramate” | “10,606” | “8.302” | “15,981” | | “Levetiracetam” | “11,157” | “8.316” | “18,731” | | “Pregabalin” | “11,291” | “8.301” | “22,721” | | “Tiagabine” | “11,673” | “8.281” | “32,679” | | “Lacosamide” | “11,777” | “8.24” | “66,256” | | “Zonisamide” | “13,237” | “8.26” | “68,397” | | “Eslicarbazepine acetate” | “13,322” | “8.279” | “53,585” | Source: [Nunes et al. (2013)](https://pmc.ncbi.nlm.nih.gov/articles/PMC3626368/) #### Add-on retigabine versus add-on lacosamide and no add-on treatment in uncontrolled focal seizures, Sweden: Bolin et al. (2013) Relevance: Evaluates add-on retigabine (ezogabine), a KV7 potassium channel opener with the mechanism of azetukalner that section 2 compares with it, against lacosamide and against no adjunctive treatment in refractory epilepsy in Sweden. > “To calculate comparative incremental cost-effectiveness ratios (cost per quality-adjusted life year, QALY) and net marginal benefits for retigabine as add-on treatment for patients with uncontrolled focal seizures as compared to add-on lacosamide treatment and no add-on treatment, respectively.” > “Calculations were performed using a validated decision-tree model.” > “The study population consisted of adult patients with focal-onset epilepsy in published randomized placebo-controlled add-on trials of retigabine or lacosamide.” > “2009 prices were used for all costs.” > “Results were reported for a 2-year follow-up period.” > “Retigabine add-on treatment was both more effective and less costly than lacosamide add-on treatment, and the cost per additional QALY for the retigabine no add-on (standard) therapy comparison was estimated at 2009€ 15,753.” > “Using a willingness-to-pay threshold for a QALY of € 50,000, the net marginal values were estimated at 2009€ 605,874 for retigabine vs lacosamide and 2009€ 2,114,203 for retigabine vs no add-on, per 1,000 patients.” > “The probabilistic analyses showed that the likelihood that retigabine treatment is cost-effective is at least 70%.” Source: [Bolin et al. (2013)](https://pubmed.ncbi.nlm.nih.gov/23368976/) ### 1.3 The same disease in other populations or settings #### Initial monotherapy antiseizure medications versus carbamazepine in newly diagnosed focal epilepsy, United States: Hu et al. (2025) Relevance: Compares antiseizure medications as initial monotherapy for focal epilepsy in the United States from a societal perspective, an earlier line of therapy than the adjunctive use studied in the X-TOLE trials, and is quoted in section 4.1 of the report. Access: Full text not retrieved > “This study aims to compare the cost-effectiveness of new ASMs and traditional ASMs as first-line monotherapy for newly diagnosed focal epilepsy.” > “We used a Markov model to evaluate the lifetime cost-effectiveness of 10 ASMs in the treatment of focal epilepsy, with lacosamide (LCM) as a control, from the perspective of society in the United States.” > “The cycle of the model is 6 months.” > “Willingness to pay was defined as $150 000 per quality-adjusted life year (QALY).” > “The base case analysis showed that carbamazepine (CBZ) was the least costly ASM and more effective than valproic acid (VPA), levetiracetam (LEV), gabapentin (GBP), topiramate (TPM), and lamotrigine (LTG) from an American social perspective.” > “In contrast, oxcarbazepine (OXC), phenytoin (PHT), phenobarbitone (PHB), LCM, and zonisamide (ZNS) were more effective than CBZ, with incremental cost-effectiveness ratios of $334 703.50, $325 610.99, $3 037 148.62, $1 178 954.91, and $108 153 360.85/QALY, respectively.” > “When generic drugs are used, PHT, OXC, and CBZ remain the three most cost-effective options.” Source: [Hu et al. (2025)](https://pubmed.ncbi.nlm.nih.gov/39841033/) #### Vagus nerve stimulation added to antiseizure medications versus antiseizure medications alone in drug-resistant epilepsy, United States: Raspin et al. (2023) Relevance: Evaluates vagus nerve stimulation added to antiseizure medications in drug-resistant epilepsy in the United States from a payer perspective, a nonpharmacologic add-on treatment section 2 lists for drug-resistant seizures. > “This study was designed, using a US Medicare perspective, to estimate costs and quality-adjusted life years (QALYs) associated with VNS as an adjunct to ongoing ASM therapy, compared to ASMs alone.” > “We developed a cohort state transition model in Microsoft Excel, with four health states defined by different percentage reductions in seizure frequency, with a 3-month cycle and transition probabilities derived from published clinical trials and registry data.” > “Under base case assumptions, treatment with VNS was associated with a 0.385 QALY gain and a $109,678 saving per patient, when compared with ASM therapy alone.” > “The incremental net monetary benefit (iNMB) was $128,903 at a threshold of $50,000 per QALY, with the positive iNMB indicating that VNS is a highly cost effective treatment.” > “Sensitivity analyses supported this conclusion.” Source: [Raspin et al. (2023)](https://pubmed.ncbi.nlm.nih.gov/36691763/) #### Responsive neurostimulation versus pharmacotherapy alone in drug-resistant focal onset epilepsy, United States: Youngerman et al. (2021) Relevance: Evaluates responsive neurostimulation against pharmacotherapy in drug-resistant focal onset epilepsy in the United States from a payer perspective. Access: Not open access Not quoted: The result for each of the three utility estimates is reported in the full text, which is closed access. > “We created and analyzed a decision model for treatment with RNS therapy versus pharmacotherapy using a semi-Markov process.” > “We adopted a public payer perspective and used the maximum duration of 9 years in the RNS long-term follow-up study as the time horizon.” > “We used seizure frequency data to model changes in quality of life and estimated the impact of RNS therapy on the annual direct costs of epilepsy care.” > “Based on three different calculated utility value estimates, the incremental cost-effectiveness ratio (ICER) for RNS therapy (with continued pharmacotherapy) compared to pharmacotherapy alone ranged between $28 825 and $46 596.” > “Multiple sensitivity analyses yielded ICERs often below $50 000 per QALY and consistently below $100 000/QALY.” Source: [Youngerman et al. (2021)](https://pubmed.ncbi.nlm.nih.gov/34458986/) #### Surgery and referral for surgical evaluation versus continued medical management in drug-resistant temporal lobe epilepsy, United States: Sheikh et al. (2020) Relevance: Evaluates resective surgery against continued medical management in drug-resistant temporal lobe epilepsy in the United States, a focal epilepsy for which section 2 lists epilepsy surgery. Access: Free full text Not quoted: The costs and QALYs of each strategy by perspective are reported in table 3, which PMC shows as an image. > “We use a semi-Markov model to assess the cost-effectiveness of surgery and surgical evaluation over a lifetime horizon.” > “We adopt both health care and societal perspectives, including direct health care costs (e.g., surgery, antiepileptic drugs) and indirect costs (e.g., lost earnings by patients and care providers.)” > “We modeled global discount rate as a variable with a normal distribution (with a mean of 3%) and included this variable in sensitivity analyses.” > “Epilepsy surgery is cost-effective compared to medical management in surgically eligible patients by virtue of being cost-saving ($328,000 vs $423,000) and more effective (16.6 vs 13.6 QALY) than medical management in the long run.” > “Surgical evaluation is cost-effective in patients with DR-TLE even if the probability of being deemed a surgical candidate is only 5%.” > “For patients who are surgically eligible, surgery becomes cost effective within 3 to 4 years (depending on whether we consider the societal or health care perspective.) For patients diagnosed with DR-TLE, referral for surgical evaluation becomes a cost-effective strategy for the cohort within 5 to 7 years.” > “When the simulations are run until cohort death (i.e., lifetime time horizon), 84% of simulations recommend surgery among surgically eligible patients from the health care perspective, and 89% of simulations recommend surgery from the societal perspective.” > “Among patients with DR-TLE who have not yet received surgical evaluation, 80% of simulations favored referral from the health care perspective, and 78% favored referral from the societal perspective.” Source: [Sheikh et al. (2020)](https://pmc.ncbi.nlm.nih.gov/articles/PMC7538217/) #### Adjunctive perampanel versus conventional antiepileptic drugs alone in children with uncontrolled focal seizures, China: Hu and Dai (2022) Relevance: Evaluates adjunctive perampanel for uncontrolled focal seizures in pediatric patients in China, a younger population than the adults enrolled in the X-TOLE trials. > “A Markov model was established to conduct an analysis from the perspective of the Chinese health system and society.” > “The cycle period of the model is 6 months, which is consistent with the core phase of the clinical trial.” > “Due to the limited efficacy data, we only compared the 5-year cost-effectiveness of the treatments between the 2 groups.” > “The discount rate was 5% according to Chinese guidelines for pharmaco-economic evaluations.” > “Compared to maintaining conventional therapy, adding PER as adjuvant therapy increased the cost by $3,449.85 over 5 years, with an incremental QALY of 0.40, resulting in an ICER of $8,582.58 per additional QALY” > “For example, the probability of the PER + AEDs treatment being cost-effective was 76.72% and 89.43% at a willingness-to-pay of $11,293/QALY and $33,879/QALY.” > “The ICER of the PER + AEDs treatment compared to the AEDs treatment was $19,710.96 per QALY in pediatric patients aged 4 to <7 years with focal seizures, and $7,167.95 per QALY in patients aged 7 to <12 years” Source: [Hu and Dai (2022)](https://pmc.ncbi.nlm.nih.gov/articles/PMC9011307/) ### 1.4 Related diseases and analogous treatments No evidence found. ## 2 Utility weights ### 2.1 Utility weights from analyses of Azetukalner (XEN1101) No evidence found. ### 2.2 Utility weights for the same indication #### Utility weights for seizure control states and refractory seizures with drug-related side effects, refractory epilepsy: Messori et al. (1998) Relevance: Utilities for seizure control states and for refractory seizures with drug-related side effects in refractory epilepsy, obtained by interviewing a group of people with epilepsy. Access: Not open access Not quoted: The utility weights are reported in the full text, which is closed access. > “quality-of-life values were obtained by prospectively interviewing a separate group of 81 patients referred to our institution with epilepsy” Source: [Messori et al. (1998)](https://pubmed.ncbi.nlm.nih.gov/9551700/) #### Utility weights by annual seizure frequency and seizure freedom, partial-onset seizures: Zhang et al. (2021) Relevance: Utilities by annual seizure frequency band and for seizure freedom in adjunctive treatment of partial-onset seizures. > “Health state utility values were acquired from the National Health and Wellness Survey of Kantar Health” Source: [Zhang et al. (2021)](https://pmc.ncbi.nlm.nih.gov/articles/PMC8290415/) | Health state | Utility | | --- | --- | | “≥53 seizures/year” | “0.619” | | “13–52 seizures/year” | “0.628” | | “≤ 12 seizures/year” | “0.673” | | “Seizure free” | “0.711” | Source: [Zhang et al. (2021)](https://pmc.ncbi.nlm.nih.gov/articles/PMC8290415/) #### Utility weights for seizure freedom and seizure reduction above and below 50%, focal onset seizures: Väätäinen et al. (2020) Relevance: Utilities for seizure freedom and for seizure reduction above and below the responder threshold in adjunctive treatment of focal onset seizures, states that correspond to the responder and seizure-freedom outcomes reported for X-TOLE. > “The HRQoL values used were 0.869 for seizure freedom, 0.805 for ≥ 50% and 0.623 for < 50% reduction in seizures (unpublished EQ-5D-3L data from SANAD study” Source: [Väätäinen et al. (2020)](https://pmc.ncbi.nlm.nih.gov/articles/PMC6979440/) #### Utility weights for seizure freedom, response, nonresponse, withdrawal, and adverse events, refractory focal epilepsy: Bolin et al. (2013) Relevance: Utilities for seizure freedom, response, nonresponse, withdrawal, and adverse events in add-on treatment of refractory focal epilepsy with retigabine, a KV7 potassium channel opener. Access: Not open access Not quoted: The utility weights are reported in the full text, which is closed access. > “Healthcare utilization and QALY for each treatment alternative were calculated.” Source: [Bolin et al. (2013)](https://pubmed.ncbi.nlm.nih.gov/23368976/) #### Utility weights for days with seizure and days with adverse events, refractory partial epilepsy: Vera-Llonch et al. (2008) Relevance: Utilities assigned to each day of follow-up according to whether a seizure or a side effect occurred, in add-on pregabalin treatment of refractory partial epilepsy. Access: Not open access Not quoted: The utility weights are reported in the full text, which is closed access. > “We assigned health-state utilities to each day of follow-up based on whether or not seizure or side effects were predicted to occur.” Source: [Vera-Llonch et al. (2008)](https://pubmed.ncbi.nlm.nih.gov/17822431/) #### Utility weights by response level, subsequent treatment, and treatment-emergent adverse events, drug-resistant focal-onset seizures: Calleja et al. (2022) Relevance: Utilities by level of response to adjunctive cenobamate and comparators, for subsequent antiseizure medications, and a disutility for treatment-emergent adverse events in drug-resistant focal-onset seizures. Access: Free full text > “SF-6D values were sourced from a mapping study” > “to reflect QoL according to health state: no response (0.50), moderate response (0.57), high response (0.61), very high response (0.61), and seizure freedom (0.65).” > “Utility values for subsequent ASM treatment (0.55), post-surgery (0.61), and post-VNS (0.56) were calculated as weighted averages of the response rate utility values and patients’ distribution among different levels of response to treatment.” > “The TEAE disutility value (−0.06) and the disutility duration (28 days) were collected from the published literature to calculate the total QALY decrement (−0.0047)” Source: [Calleja et al. (2022)](https://doi.org/10.1080/14737167.2022.2107507) ### 2.3 Utility weights for the same disease in other populations or settings #### Utility weights by percentage reduction in seizure frequency, drug-resistant epilepsy: Raspin et al. (2023) Relevance: Utilities by percentage reduction in seizure frequency in drug-resistant epilepsy, used in a United States Medicare model of vagus nerve stimulation as an add-on treatment. Access: Free full text Not quoted: The utility weights are reported in Table 1, which the publisher's article page loads only on request and the quote checker does not read. > “The evaluation utilizes a previously published model, which was updated to use costs, health-related quality of life, and mortality estimates relevant to the US Medicare setting.” Source: [Raspin et al. (2023)](https://pubmed.ncbi.nlm.nih.gov/36691763/) #### Utility weights for seizure-free and not seizure-free states and antiseizure medication adverse events, focal epilepsy: Hu et al. (2025) Relevance: Utilities for seizure-free and not seizure-free focal epilepsy and a disutility for adverse events of antiseizure medications. Access: Full text not retrieved Not quoted: The utility weights are reported in the full text, which this page does not quote. > “Effectiveness, cost data, and health state utilities were obtained from published literature.” Source: [Hu et al. (2025)](https://pubmed.ncbi.nlm.nih.gov/39841033/) #### Utility weights by annual focal seizure frequency and seizure freedom, children with focal seizures: Hu and Dai (2022) Relevance: Utilities by annual focal seizure frequency band and for seizure freedom in pediatric patients receiving adjunctive treatment. > “A total of 176 EQ-5D-Y-3L observations from 60 patients were assigned to calculate the health state utility value.” Source: [Hu and Dai (2022)](https://pmc.ncbi.nlm.nih.gov/articles/PMC9011307/) | Health state | Utility | | --- | --- | | “≥53 seizures per year” | “0.284” | | “13–52 seizures per year” | “0.596” | | “1–12 seizures per year” | “0.620” | | “Seizure free” | “0.914” | Source: [Hu and Dai (2022)](https://pmc.ncbi.nlm.nih.gov/articles/PMC9011307/) ### 2.4 Utility weights for related diseases and analogous treatments No evidence found. ## 3 Search strategy | Dataset | Query | Results | | --- | --- | --- | | Methods | azetukalner OR XEN1101 | 0 | | Ratios | azetukalner OR XEN1101 | 0 | | Ratios | "focal onset seizures" OR "partial-onset seizures" OR "focal seizures" OR "partial seizures" OR "focal epilepsy" | 59 | | Ratios | cenobamate OR brivaracetam OR perampanel OR lacosamide OR eslicarbazepine | 45 | | Ratios | "drug-resistant epilepsy" OR "refractory epilepsy" OR "intractable epilepsy" OR "uncontrolled epilepsy" | 59 | | Ratios | epilepsy AND (adjunctive OR "add-on") | 49 | | Ratios | retigabine OR ezogabine | 2 | | Weights | epilepsy OR seizure OR seizures OR "seizure-free" | 392 | ## Related pages - [Azetukalner (XEN1101): Focal onset seizures](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures) · [Markdown](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures.md) - [Azetukalner (XEN1101) in Focal onset seizures: Terms and abbreviations](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures/terms-and-abbreviations) · [Markdown](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures/terms-and-abbreviations.md) - [Azetukalner (XEN1101): Focal onset seizures](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures/executive-summary) · [Markdown](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures/executive-summary.md) - [Azetukalner (XEN1101) in Focal onset seizures: Product information and disease description](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures/product-information-and-disease-description) · [Markdown](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures/product-information-and-disease-description.md) - [Azetukalner (XEN1101) in Focal onset seizures: Clinical evidence](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures/clinical-evidence) · [Markdown](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures/clinical-evidence.md) - [Azetukalner (XEN1101) in Focal onset seizures: Economic information and modeling report](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures/economics) · [Markdown](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures/economics.md) - [Azetukalner (XEN1101) in Focal onset seizures: References](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures/references) · [Markdown](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures/references.md) - [Azetukalner (XEN1101) in Focal onset seizures: prevalence by geography](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures/prevalence) · [Markdown](https://www.evicenter.com/drugs/azetukalner--focal-onset-seizures/prevalence.md)