A Randomized, Double-Blind, Sham-Controlled, Clinical Trial of Auricular Vagus Nerve Stimulation for the Treatment of Active Rheumatoid Arthritis.

OBJECTIVE: Preliminary evidence suggests that vagus nerve stimulation (VNS) may have some benefit in patients with rheumatoid arthritis (RA); however, prior studies have been small and/or uncontrolled; this study aimed to address that gap. METHODS: This randomized, double-blind, sham-controlled trial enrolled patients aged 18 to 75 years with active RA who had failed conventional synthetic disease-modifying antirheumatic drugs (DMARDs) and were naïve to biologic and/or targeted synthetic DMARDs. All patients received an auricular vagus nerve stimulator and were randomized 1:1 to active stimulation or sham. The primary endpoint was the proportion of patients achieving 20% improvement in American College of Rheumatology criteria (ACR20) at week 12. Secondary endpoints included mean changes in disease activity score of 28 joints with C-reactive protein (DAS28-CRP) and Health Assessment Questionnaire-Disability Index (HAQ-DI). RESULTS: A total of 113 patients (mean age 54 years; 82% female) enrolled, and 101 patients (89.4%) completed week 12. ACR20 response at week 12 was 25.0% for active stimulation versus 26.9% for sham (difference vs. sham, -1.9; 95% CI, -18.8, 14.9, P = 0.823). The least square mean ± SE change in DAS28-CRP was -0.95 ± 0.16 for active stimulation and -0.66 ± 0.16 for sham (P = 0.201); in HAQ-DI it was -0.19 ± 0.06 for active stimulation and -0.02 ± 0.06 for sham (P = 0.044). Adverse events occurred in 17 patients (15%); all were mild or moderate. CONCLUSION: Auricular VNS did not meaningfully improve RA disease activity. If VNS with other modalities is pursued in the future for the treatment of RA, larger, controlled studies will be needed to understand its utility.

Intrathecal Onasemnogene Abeparvovec for Sitting, Nonambulatory Patients with Spinal Muscular Atrophy: Phase I Ascending-Dose Study (STRONG).

BACKGROUND: Spinal muscular atrophy (SMA) is a neuromuscular disorder arising from biallelic non-functional survival motor neuron 1 (SMN1) genes with variable copies of partially functional SMN2 gene. Intrathecal onasemnogene abeparvovec administration, at fixed, low doses, may enable treatment of heavier patients ineligible for weight-based intravenous dosing. OBJECTIVE: STRONG (NCT03381729) assessed the safety/tolerability and efficacy of intrathecal onasemnogene abeparvovec for sitting, nonambulatory SMA patients. METHODS: Sitting, nonambulatory SMA patients (biallelic SMN1 loss, three SMN2 copies, aged 6-<60 months) received a single dose of intrathecal onasemnogene abeparvovec. Patients were enrolled sequentially into one of three (low, medium, and high) dose cohorts and stratified into two groups by age at dosing: younger (6-<24 months) and older (24-<60 months). Primary endpoints included safety/tolerability, independent standing ≥3 seconds (younger group), and change in Hammersmith Functional Motor Scale Expanded (HFMSE) from baseline (older group) compared with historic controls. RESULTS: Thirty-two patients were enrolled and completed the study (medium dose, n = 25). All patients had one or more treatment-emergent adverse events, with one serious and related to treatment (transaminase elevations). No deaths were reported. One of 13 patients (7.7%) in the younger group treated with the medium dose achieved independent standing. At Month 12 for the older group receiving the medium dose, change from baseline in HFMSE was significantly improved compared with the SMA historic control population (P < 0.01). CONCLUSIONS: Intrathecal onasemnogene abeparvovec was safe and well-tolerated. Older patients treated with the medium dose demonstrated increases in HFMSE score greater than commonly observed in natural history.

Onasemnogene abeparvovec for presymptomatic infants with two copies of SMN2 at risk for spinal muscular atrophy type 1: the Phase III SPR1NT trial.

SPR1NT ( NCT03505099 ) was a Phase III, multicenter, single-arm study to investigate the efficacy and safety of onasemnogene abeparvovec for presymptomatic children with biallelic SMN1 mutations treated at ≤6 weeks of life. Here, we report final results for 14 children with two copies of SMN2, expected to develop spinal muscular atrophy (SMA) type 1. Efficacy was compared with a matched Pediatric Neuromuscular Clinical Research natural-history cohort (n = 23). All 14 enrolled infants sat independently for ≥30 seconds at any visit ≤18 months (Bayley-III item #26; P < 0.001; 11 within the normal developmental window). All survived without permanent ventilation at 14 months as per protocol; 13 maintained body weight (≥3rd WHO percentile) through 18 months. No child used nutritional or respiratory support. No serious adverse events were considered related to treatment by the investigator. Onasemnogene abeparvovec was effective and well-tolerated for children expected to develop SMA type 1, highlighting the urgency for universal newborn screening.

Onasemnogene abeparvovec for presymptomatic infants with three copies of SMN2 at risk for spinal muscular atrophy: the Phase III SPR1NT trial.

Most children with biallelic SMN1 deletions and three SMN2 copies develop spinal muscular atrophy (SMA) type 2. SPR1NT ( NCT03505099 ), a Phase III, multicenter, single-arm trial, investigated the efficacy and safety of onasemnogene abeparvovec for presymptomatic children with biallelic SMN1 mutations treated within six postnatal weeks. Of 15 children with three SMN2 copies treated before symptom onset, all stood independently before 24 months (P < 0.0001; 14 within normal developmental window), and 14 walked independently (P < 0.0001; 11 within normal developmental window). All survived without permanent ventilation at 14 months; ten (67%) maintained body weight (≥3rd WHO percentile) without feeding support through 24 months; and none required nutritional or respiratory support. No serious adverse events were considered treatment-related by the investigator. Onasemnogene abeparvovec was effective and well-tolerated for presymptomatic infants at risk of SMA type 2, underscoring the urgency of early identification and intervention.

Antipsychotic Efficacy of KarXT (Xanomeline-Trospium): Post Hoc Analysis of Positive and Negative Syndrome Scale Categorical Response Rates, Time Course of Response, and Symptom Domains of Response in a Phase 2 Study.

Objective: To evaluate Positive and Negative Syndrome Scale (PANSS) categorical response rates, time course of response, and symptom subdomains of response with the combination oral agent KarXT (xanomeline-trospium) in the treatment of schizophrenia.Methods: Post hoc analysis was conducted for EMERGENT-1 (NCT03697252), a 5-week, inpatient, placebo-controlled, phase 2 study of acute psychosis in patients who met DSM-5 criteria for schizophrenia. The EMERGENT-1 study was conducted between September 2018 and August 2019. Categorical thresholds of response used were PANSS total score reductions of ≥ 20%, ≥ 30%, ≥ 40%, and ≥ 50% between baseline and study end. Number needed to treat (NNT) for each categorical threshold was calculated. The proportion of KarXT- and placebo-treated patients achieving each response threshold at weeks 2, 4, and 5 was assessed. Marder 5-factor analysis of PANSS assessed response with KarXT across symptom domains.Results: A total of 83 patients in the KarXT group and 87 patients in the placebo group were included in the modified intent-to-treat analysis. Response rates with KarXT ranged from 59.0% for a ≥ 20% threshold to 15.7% for a ≥ 50% threshold. All response rates with KarXT were significantly higher than in the placebo arm (P < .05), with NNTs ranging from 3 (≥ 20% improvement) to 11 (≥ 50% improvement). KarXT was associated with a significantly higher response rate relative to placebo as early as 2 weeks for ≥ 20% (P = .0001) and ≥ 30% (P = .0022) thresholds and at 4 weeks for the ≥ 40% (P = .0049) and ≥ 50% (P = .0041) thresholds. Each of the Marder 5 factors showed significant differences favoring KarXT over placebo (P < .05) by 2 weeks and continuing through week 5 (endpoint Cohen d effect sizes, 0.48-0.66).Conclusions: KarXT provided clinically meaningful responder rates on PANSS total score compared with placebo at each response threshold, providing further support of the successful primary and secondary endpoints. Response was demonstrated as early as 2 weeks relative to placebo. KarXT demonstrated improvements vs placebo in all 5 factors (positive symptoms, negative symptoms, disorganized thought, uncontrolled hostility, and anxiety/depression).Trial Registration: ClinicalTrials.gov identifier: NCT03697252.

Etiology and outcomes of amputation in patients with peripheral artery disease in the EUCLID trial.

OBJECTIVE: Amputation remains a frequent and feared outcome in patients with peripheral artery disease (PAD). Although typically characterized as major or minor on the extent of tissue loss, the etiologies and outcomes after amputation by extent are not well-understood. In addition, emerging data suggest that the drivers and outcomes of amputation in patients with PAD may differ in those with and without diabetes mellitus (DM). METHODS: The EUCLID trial randomized 13,885 patients with symptomatic PAD, including 5345 with concomitant diabetes, to ticagrelor or clopidogrel and followed them for long-term outcomes. Amputations were prospectively reported by trial investigators. Their primary and contributing drivers were adjudicated using safety data, including infection, ischemia, or multifactorial etiologies. Outcomes following major and minor amputations were analyzed, including recurrent amputation, major adverse limb events, adverse cardiovascular events, and mortality. Multivariable logistic regression models were used to identify independent predictors of minor amputations. Analyses were performed overall and stratified by the presence or absence of DM at baseline. RESULTS: Of the patients randomized, 398 (2.9%) underwent at least one lower extremity nontraumatic amputation, for a total of 511 amputations (255 major and 256 minor) over a median of 30 months. A history of minor amputation was the strongest independent predictor for a subsequent minor amputation (odds ratio, 7.29; 95% confidence interval, 5.17-10.30; P < .001) followed by comorbid DM (odds ratio, 4.60; 95% confidence interval, 3.16-6.69; P < .001). Compared with patients who had a major amputation, those with a minor amputation had similar rates of subsequent major amputation (12.2% vs 13.6%), major adverse limb events (15.1% vs 14.9%), and major adverse cardiovascular events (17.6% vs 16.3%). Ischemia alone was the primary driver of amputation (51%), followed by infection alone (27%), and multifactorial etiologies (22%); however, infection was the most frequent driver in those with DM (58%) but not in those without DM (15%). CONCLUSIONS: Outcomes after amputation remain poor regardless of whether they are categorized as major or minor. The pattern of amputation drivers in PAD differs by history of DM, with infection being the dominant etiology in those with DM and ischemia in those without DM. Greater focus is needed on the prognostic importance of minor amputation and of the multifactorial etiologies of amputation in PAD. Nomenclature with anatomical description of amputations and eliminating terms "major" or "minor" would seem appropriate.

Ankle-Brachial Index for Risk Stratification in Patients With Symptomatic Peripheral Artery Disease With and Without Prior Lower Extremity Revascularization: Observations From the EUCLID Trial.

[Figure: see text].

Impact of chronic kidney disease on hemoglobin among patients with peripheral artery disease treated with P2Y12 inhibitors: Insights from the EUCLID trial.

Patients with chronic kidney disease may develop new or more severe anemia when treated with antiplatelet agents due to blood loss in conjunction with impaired erythropoiesis. Because anemia independently predicts limb amputation and mortality among patients with peripheral artery disease (PAD), we evaluated the relationship between estimated glomerular filtration rate (eGFR) and hemoglobin (Hb) levels in the EUCLID trial in which patients with symptomatic PAD were randomized to ticagrelor or clopidogrel. At baseline, 9025, 1870, and 1000 patients had eGFR ⩾ 60, 45-59, and < 45 mL/min/1.73 m2, respectively. The mean fall in Hb during the trial was 0.46 ± 1.68 g/dL and did not differ by baseline eGFR category, although Hb fall ⩾ 10% was more frequent among patients with lower eGFR (p for trend < 0.0001). On-study treatment with iron, erythropoiesis-stimulating agents, and/or red blood cell transfusion was reported for 479 (5.3%), 165 (8.8%), and 129 (12.9%) patients in the three eGFR categories, respectively (p for trend < 0.0001). After adjustment for baseline and post-randomization effects, those not receiving anemia treatment had a smaller reduction in Hb from baseline than those receiving anemia treatment (p < 0.0001). Other determinants of Hb reduction included absence of on-study myocardial infarction, coronary or peripheral revascularization, residence outside North America, male sex, and baseline eGFR. We conclude that among patients with PAD treated with P2Y12 inhibitors, lower baseline eGFR was associated with a greater reduction in Hb. ClinicalTrials.gov Identifier: NCT01732822.

Association of Hypertension and Arterial Blood Pressure on Limb and Cardiovascular Outcomes in Symptomatic Peripheral Artery Disease: The EUCLID Trial.

BACKGROUND: Current guidelines recommend aggressive management of hypertension. Recent evidence suggested potential harm with low blood pressure targets in patients with peripheral artery disease. We investigated the association of a history of hypertension and office systolic blood pressure (SBP) with major adverse cardiovascular events (MACEs) and major adverse limb events (MALEs). METHODS AND RESULTS: The EUCLID trial (Examining the Use of Ticagrelor in Peripheral Artery Disease) included 13 885 participants with symptomatic peripheral artery disease; median follow-up was 30 months. Cox proportional hazards regression was used to calculate hazard ratios (HRs) for any MACE, MALE, and MALE including lower extremity revascularization. A clinical history of arterial hypertension was present in 10 857 (78%) participants, and these participants were older and more likely to be female when compared with the 3026 (22%) patients without hypertension. In patients with a history of hypertension, the adjusted hazard ratio for MACE was 0.94, 95% CI, 0.82-1.08; P=0.39, and the adjusted hazard ratio for MALE was 1.08, 95% CI, 0.96-1.23; P=0.21. During follow-up, average SBP was 135 mm Hg (125-145). Every 10 mmHg increase in SBP>125 mmHg was associated with an increased risk of MACE (HR, 1.10 [95% CI, 1.06-1.14]; P<0.001), a marginally increased risk of MALE (HR, 1.07 [95% CI, 1.00-1.15]; P=0.062), and an increased risk of MALE/lower extremity revascularization (HR, 1.08 [95% CI, 1.04-1.11]; P<0.001). Every decrease in 10 mmHg SBP ≤125 mmHg was associated with an increased risk of MACE (HR, 1.19 [95% CI, 1.09-1.31]; P<0.001) but not MALE or MALE/lower extremity revascularization (HR, 1.02 [95% CI, 0.84-1.23], P=0.824; HR, 1.04 [95% CI, 0.95-1.13], P=0.392, respectively). CONCLUSIONS: History of hypertension was not associated with higher hazard for MACE or MALE in patients with peripheral artery disease. In contrast, there was a higher hazard of MACE in patients with out-of-target low and high SBP. High but not low SBP was associated with an increased risk of ischemic limb events. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01732822.

From rote to reasoned: Examining the role of pedagogical reasoning in practice-based teacher education.

•Critics worry that practice-based teacher education focuses on teaching behaviors and not pedagogical reasoning.•Practice-based teacher learning experiences can be aimed at developing pedagogical reasoning.•Teacher educators use particular practices to highlight pedagogical reasoning when working on practice with novices.•We need more nuanced frameworks for describing, implementing, and studying teacher education pedagogy.

Sex-Specific Risks of Major Cardiovascular and Limb Events in Patients With Symptomatic Peripheral Artery Disease.

BACKGROUND: Patients with peripheral artery disease (PAD) have a higher risk of major adverse cardiovascular events (MACE) compared with those without PAD. OBJECTIVES: The aim of this post hoc analysis was to evaluate sex-specific differences in MACE and limb events in the EUCLID (Examining Use of Ticagrelor in PAD) trial. METHODS: Cox proportional hazards models were used to compare time-to-event outcomes stratified by sex. Covariates were introduced after adjusted model selection. RESULTS: EUCLID enrolled 13,885 patients with PAD (28% women [n = 3,888]). PAD severity and medical treatment were comparable between sexes, whereas prior lower extremity revascularization was reported less frequently in women (54.8% vs. 57.3%; p = 0.006). Women were older (mean ± SD age: 67.8 ± 8.9 vs. 66.1 ± 8.2 years; p < 0.001) and more likely to have diabetes mellitus (p = 0.004), hypertension, hyperlipidemia, and chronic kidney disease (all p < 0.001). Over a mean follow-up of 30 months, women had a lower risk of MACE (9.5% vs. 11.2%; adjusted hazard ratio: 0.77; 95% confidence interval: 0.68 to 0.88; p < 0.001) and all-cause-mortality (7.6% vs. 9.7%; adjusted hazard ratio: 0.61; 95% confidence interval: 0.53 to 0.71; p < 0.001). In contrast, risk for major adverse limb events (2.6% vs. 3.0%) and hospitalization for acute limb ischemia (1.6% vs. 1.7%) were not different by sex. CONCLUSIONS: Although women with PAD are at lower risk for MACE and all-cause mortality, risk for limb events was similar between sexes over a mean follow-up of 30 months. Understanding sex-specific differences and dissociation between baseline cardiovascular risk and subsequent cardiovascular events requires further investigation. (A Study Comparing Cardiovascular Effects of Ticagrelor and Clopidogrel in Patients With Peripheral Artery Disease [EUCLID]; NCT01732822).

Teaching content in practice: Investigating rehearsals of social studies discussions.

Despite evidence of its benefits, discussion remains rare in history/social science classrooms. To address this problem, communities of teacher educators (TEs) have begun supporting novices to approximate discussion facilitation. Some scholars are concerned that this turn to practice will come at the cost of content preparation. Focusing specifically on rehearsals of discussion facilitation in three history/social science methods courses, our analysis investigates whether, how, and in what ways TEs worked on content while engaging novice teachers in practicing discussion facilitation. We found that TEs found ways to work simultaneously on content and practice during rehearsals of discussion facilitation.

Chronic kidney disease and risk for cardiovascular and limb outcomes in patients with symptomatic peripheral artery disease: The EUCLID trial.

In patients with symptomatic peripheral artery disease (PAD), the impact of chronic kidney disease (CKD) on major adverse cardiovascular events has not been fully evaluated. The Examining Use of Ticagrelor In PAD (EUCLID) trial randomized 13,885 patients with PAD to ticagrelor 90 mg twice daily or clopidogrel 75 mg daily. This post hoc analysis compared the incidence of the primary composite endpoint (cardiovascular death, myocardial infarction (MI), or ischemic stroke) in patients with CKD (eGFR < 60 mL/min/1.73 m2) with those without CKD (eGFR ⩾ 60 mL/min/1.73 m2). The primary safety endpoint was thrombolysis in MI (TIMI) major bleeding. A total of 13,483 patients were included; 3332 (25%) had CKD, of whom 237 had stage 4/5 disease. Median follow-up was approximately 30 months. After statistical adjustment, patients with CKD had a higher rate of the primary endpoint compared with those without CKD (6.75 vs 3.72 events/100 patient-years; adjusted hazard ratio (HR) 1.45, 95% CI 1.30-1.63). CKD was not associated with increased risk of hospitalization for acute limb ischemia (ALI) (adjusted HR 0.96, 95% CI 0.69-1.34) or major amputation (adjusted HR 0.92, 95% CI 0.66-1.28). CKD was not associated with a significantly increased risk of major bleeding (adjusted HR 1.21, 95% CI 0.89-1.64), but minor bleeding was significantly increased (adjusted HR 1.51, 95% CI 1.07-2.15). In conclusion, patients with PAD and CKD had higher rates of cardiovascular death, MI, and ischemic stroke, but similar rates of ALI, major amputation, and TIMI major bleeding when compared with patients without CKD. ClinicalTrials.gov Identifier: NCT01732822.

Evidence of emergent practice: Teacher candidates facilitating historical discussions in their field placements.

•Teacher candidates can facilitate text-based discussion when prepared.•Instructional scaffolds can assist candidates in facilitating discussion.•Assignments, questioning sequences, and prepared materials can support enactment.•Candidates still struggle to connect discussion to lesson's learning goal.

Subcutaneous ofatumumab in patients with relapsing-remitting multiple sclerosis: The MIRROR study.

OBJECTIVE: To assess dose-response effects of the anti-CD20 monoclonal antibody ofatumumab on efficacy and safety outcomes in a phase 2b double-blind study of relapsing forms of multiple sclerosis (RMS). METHODS: Patients (n = 232) were randomized to ofatumumab 3, 30, or 60 mg every 12 weeks, ofatumumab 60 mg every 4 weeks, or placebo for a 24-week treatment period, with a primary endpoint of cumulative number of new gadolinium-enhancing lesions (per brain MRI) at week 12. Relapses and safety/tolerability were assessed, and CD19+ peripheral blood B-lymphocyte counts measured. Safety monitoring continued weeks 24 to 48 with subsequent individualized follow-up evaluating B-cell repletion. RESULTS: The cumulative number of new lesions was reduced by 65% for all ofatumumab dose groups vs placebo (p < 0.001). Post hoc analysis (excluding weeks 1-4) estimated a ≥90% lesion reduction vs placebo (week 12) for all cumulative ofatumumab doses ≥30 mg/12 wk. Dose-dependent CD19 B-cell depletion was observed. Notably, complete depletion was not necessary for a robust treatment effect. The most common adverse event was injection-related reactions (52% ofatumumab, 15% placebo), mild to moderate severity in 97%, most commonly associated with the first dose and diminishing on subsequent dosing. CONCLUSION: Imaging showed that all subcutaneous ofatumumab doses demonstrated efficacy (most robust: cumulative doses ≥30 mg/12 wk), with a safety profile consistent with existing ofatumumab data. This treatment effect also occurred with dosage regimens that only partially depleted circulating B cells. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that for patients with RMS, ofatumumab decreases the number of new MRI gadolinium-enhancing lesions 12 weeks after treatment initiation.

A phase 2a, randomized, crossover trial of gabapentin enacarbil for the treatment of postherpetic neuralgia in gabapentin inadequate responders.

OBJECTIVE: To compare the efficacy of high-dose (3,600 mg/day) vs low-dose (1,200 mg/day) oral gabapentin enacarbil (GEn) on pain intensity in adults with postherpetic neuralgia (PHN) and a history of inadequate response to ≥1,800 mg/day gabapentin. DESIGN: Multicenter, randomized, double-blind, crossover study (NCT00617461). SETTING: Thirty-five outpatient centers in Germany and the United States. SUBJECTS: Subjects aged ≥18 years with a diagnosis of PHN. METHODS: During a 2-week baseline period, subjects received open-label treatment with 1,800 mg/day gabapentin. Subjects who had a mean 24-hour average pain intensity score ≥4 during the last 7 days of the baseline period were randomized to receive GEn (1,200 or 3,600 mg/day) for treatment period 1 (28 days), followed by GEn 2,400 mg/day (4 days), and the alternate GEn dose for treatment period 2 (28 days). RESULTS: There was a modest but significant improvement in pain intensity scores with GEn 3,600 mg vs 1,200 mg (adjusted mean [90% confidence interval] treatment difference, -0.29 [-0.48 to -0.10]; P = 0.013). The difference in efficacy between doses was observed primarily in subjects who received the higher dose during treatment period 2; certain aspects of the study design may have contributed to this outcome. Plasma steady-state gabapentin exposure during GEn treatment was as expected and consistent between treatment periods. No new safety signals or adverse event trends relating to GEn exposure were identified. CONCLUSIONS: While the overall results demonstrated efficacy in a PHN population, the differences between treatment periods confound the interpretation. These findings could provide insight into future trial designs.

The asymmetric synthesis of terminal aziridines by methylene transfer from sulfonium ylides to imines.

A new ylide-based protocol for the asymmetric aziridination of imines via methylene transfer has been developed involving the use of a simple chiral sulfonium salt and an organic strong base. A systematic study identified triisopropylphenyl sulfonylimines as optimal substrates for the process. Unexpectedly, hindered C2-symmetric sulfonyl salts incorporating bulky ethers at C-2 and C-5--which had previously been useful in the corresponding epoxidation chemistry--decomposed in these aziridination reactions via competing elimination pathways. Under optimised conditions it was found that a simple salt derived from (2R,5R)-2,5-diisopropyl thiolane could mediate asymmetric methylene transfer to a range of imines with uniformly excellent yields with 19-30% ee. Since this is a similar level of enantiomeric excess to that obtained using these same salts in epoxidation chemistry, it was concluded that if more bulky sulfonium salts could be devised which were resistant to decomposition under the reaction conditions, that highly enantioselective aziridine formation by methylene transfer would be possible.

A randomized, double-blind, placebo-controlled trial to assess the efficacy and safety of gabapentin enacarbil in subjects with neuropathic pain associated with postherpetic neuralgia (PXN110748).

UNLABELLED: Gabapentin enacarbil (GEn) is an actively transported prodrug of gabapentin that provides sustained, dose-proportional exposure to gabapentin. This randomized, double-blind, parallel-group, placebo-controlled study evaluated the safety and efficacy of 3 different maintenance doses of oral GEn in subjects with postherpetic neuralgia. Adults with a 24-hour average pain intensity score of ≥4.0 received GEn 1,200 mg, 2,400 mg, 3,600 mg, or placebo for 14 weeks (including a 1-week up-titration, 12-week maintenance, and 1-week taper). The primary endpoint was change from baseline to end of maintenance treatment in mean 24-hour average pain intensity score. The intent-to-treat population consisted of 371 subjects (GEn 1,200 mg = 107, 2,400 mg = 82, 3,600 mg = 87, placebo = 95). With regard to the primary endpoint, all 3 GEn treatment groups demonstrated a statistically significant difference relative to placebo. The adjusted mean change from baseline for the treatment groups ranged from -2.36 to -2.72 versus -1.66 for the placebo group. Exposure-response modeling suggested an ED50 around 1,200 mg/day, which was consistent with historical findings reported for gabapentin. The most commonly reported adverse events were dizziness and somnolence. All studied doses of GEn significantly improved pain associated with postherpetic neuralgia as compared to placebo and were well tolerated. PERSPECTIVE: GEn provides clinically important pain relief with doses from 1,200 mg to 3,600 mg and is generally well tolerated and efficacious. As an actively transported prodrug of gabapentin, it provides dose-proportional and extended exposure to gabapentin.