Can Matching-Adjusted Indirect Comparison Methods Mitigate Placebo Response Differences Among Patient Populations in Adjunctive Trials of Brivaracetam and Levetiracetam?

Matching-Adjusted Indirect Comparisons of Filgotinib vs Vedolizumab, Tofacitinib, and Ustekinumab for Moderately to Severely Active Ulcerative Colitis

BACKGROUND

Where head-to-head trials are lacking, indirect comparative effectiveness can aid treatment decisions. We conducted matching-adjusted indirect comparisons of clinical outcomes with filgotinib vs recently approved comparators (vedolizumab, tofacitinib, ustekinumab) in patients with moderately to severely active ulcerative colitis (UC).

METHODS

Individual patient data from the SELECTION trial (NCT02914522) for filgotinib 200 mg were weighted to match average baseline characteristics of active treatment and placebo arms in comparator trials. Efficacy outcomes were compared for biologic-naive and biologic-experienced subgroups in induction and maintenance populations, if data were available. Safety and health-related quality of life outcomes were compared in the overall maintenance population.

RESULTS

Filgotinib had a similar effect on efficacy outcomes compared with tofacitinib, ustekinumab, and subcutaneous vedolizumab in both the induction and maintenance populations. Filgotinib showed improved clinical response vs intravenous (IV) vedolizumab (odds ratio, 2.4; 95% confidence interval [CI], 1.0 to 5.5; P < .05) among the biologic-experienced induction population, and improved corticosteroid-free clinical remission (odds ratio, 15.2; 95% CI, 1.6 to 139.9; P < .05) among the biologic-naive maintenance population. Improved efficacy outcomes were reported with filgotinib compared with ustekinumab among the maintenance population. Higher estimates of serious adverse events were reported for filgotinib compared with vedolizumab IV 300 mg and tofacitinib 5 mg; however, imbalances were noted in their placebo groups. Health-related quality of life outcomes were similar between filgotinib and comparators.

CONCLUSIONS

Matching-adjusted indirect comparison results suggest superiority of filgotinib 200 mg over vedolizumab IV in terms of clinical response and corticosteroid-free clinical remission in certain patient populations, noting small sample sizes and wide CIs, which may aid the selection of advanced therapies for moderately to severely active UC. A potential increased risk of serious adverse events was reported for filgotinib 200 mg vs vedolizumab IV and tofacitinib 5 mg, but findings should be interpreted with caution owing to underlying imbalances observed between the placebo groups of SELECTION and comparator trials.

How does risdiplam compare with other treatments for Types 1-3 spinal muscular atrophy: a systematic literature review and indirect treatment comparison

Aim: To conduct indirect treatment comparisons between risdiplam and other approved treatments for spinal muscular atrophy (SMA). Patients & methods: Individual patient data from risdiplam trials were compared with aggregated data from published studies of nusinersen and onasemnogene abeparvovec, accounting for heterogeneity across studies. Results: In Type 1 SMA, studies of risdiplam and nusinersen included similar populations. Indirect comparison results found improved survival and motor function with risdiplam versus nusinersen. Comparison with onasemnogene abeparvovec in Type 1 SMA and with nusinersen in Types 2/3 SMA was challenging due to substantial differences in study populations; no concrete conclusions could be drawn from the indirect comparison analyses. Conclusion: Indirect comparisons support risdiplam as a superior alternative to nusinersen in Type 1 SMA.

Cost-utility model of brivaracetam in the adjunctive treatment of patients with epilepsy in Spain

OBJECTIVE

This study aims to assess the cost utility of Brivaracetam compared with the third-generation anti-epileptic drugs used as standard care.

METHODS

A cost utility analysis of Brivaracetam was carried out with other third-generation comparators. The treatment pathway of a hypothetical cohort over a period of 2 years was simulated using the Markov model. Data for effectiveness and the QALYs of each health status for epilepsy, as well as for the disutilities of adverse events of treatments, were analyzed through a studies review. The cost of the anti-epileptics and the use of medical resources linked to the different health statuses were taken into consideration. A probabilistic sensitivity analysis was performed using a Monte Carlo simulation.

RESULTS

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. The ICUR sensitivity is greater for increases in the price of Brivaracetam than for decreases, and for Eslicarbizapine over the other adjunctives considered in the analysis.

CONCLUSIONS

Treatment with Brivaracetam resulted in cost effective and incremental quality adjusted life years come at an acceptable cost.

Safety and tolerability of adjunctive brivaracetam in children with focal seizures: Interim analysis of pooled data from two open-label trials

OBJECTIVE

To evaluate long-term safety and tolerability of adjunctive brivaracetam (BRV) in children with epilepsy.

METHODS

This was an interim analysis (cut-off March 15, 2017) of pooled data from two open-label, single-arm, multicentre trials. N01263 (NCT00422422) was a 3-week trial of BRV 0.8-4 mg/kg/day in patients (1 month-<16 years) with epilepsy. Patients who completed this trial could continue into a long-term follow-up trial (N01266, NCT01364597) which also directly enrolled patients (4-<17 years) with focal seizures. After dose-escalation, patients received BRV 1-5 mg/kg/day (maximum 200 mg/day) during long-term evaluation. Data are reported for patients aged 4 to <16 years with focal seizures.

RESULTS

The safety set comprised 149 patients: 34 from the initial trial (26 entered long-term trial) and 115 directly enrolled into the long-term trial. At the cut-off, 90 patients were receiving BRV (total exposure: 299.4 patient-years). Treatment-emergent adverse events (TEAEs) were reported by 140/149 (94.0%) patients, most commonly (≥20%) nasopharyngitis (24.8%), pharyngitis (22.1%), convulsion (21.5%), and pyrexia (20.1%). TEAEs considered drug-related by the investigator were reported by 56/149 (37.6%) patients, most commonly somnolence (6.0%). Two patients died; neither death was considered related to BRV. Mean changes from baseline in child behaviour rating scales were small; most patients remained in their baseline category.

CONCLUSION

In this pooled analysis of two open-label trials including long-term data, adjunctive BRV was generally well tolerated in children aged 4 to <16 years with focal seizures. These findings supported approval of BRV as a new therapy option for children aged ≥4 years with focal seizures.

Relative performance of brivaracetam as adjunctive treatment of focal seizures in adults: a network meta-analysis

Objective: To estimate the relative efficacy, safety and tolerability of adjunctive brivaracetam and other antiepileptic drugs (AEDs) using a Bayesian network meta-analysis (NMA) approach. Methods: A systematic literature review (SLR) identified randomized controlled trials of AEDs treating focal (partial-onset) seizures for ≥8 weeks and assessed them for inclusion in the NMA. Bayesian random-effects NMA was performed for several outcomes. All interventions within the licensed dose range were included in the network of evidence. Results: The SLR identified 82 studies; 65 were included in the NMA. These studies had baseline mean age 33.1-38.0 years, mean duration of epilepsy 18.7-23.0 years and median seizure frequency/28 days 8.1-11.8. All AEDs had significantly higher odds than placebo of achieving ≥50% responder rates (odds ratios 1.83-3.58) and all AEDs had a trend of higher odds than placebo of achieving seizure freedom (odds ratios 1.36-5.73), most being statistically significant. Tolerability outcomes were comparable between AEDs; most AEDs had higher odds than placebo of treatment-emergent adverse events leading to discontinuation, serious AEs, nausea, fatigue, dizziness and somnolence. Conclusions: This NMA would appear to show relative equivalence in efficacy, safety and tolerability outcomes of the included AEDs. However, patient heterogeneity within trials and in clinical practice should be considered when interpreting these results. While NMAs are based on the best available evidence the authors suggest that, due to the inability of NMAs to capture unmeasured confounding factors and population heterogeneity, NMAs must not be the sole basis for comparative treatment recommendations.