PHN

Horizant^® 600 mg BID significantly reduced PHN nerve pain as early as week 1¹⁰

PHN

Greater reduction in pain score than placebo at week 1 with Horizant^® 600 mg twice daily¹⁰

Reduction of 24-hour average pain score during week 1 up-titration vs placebo¹⁰

Efficacy

Safety

PHN Clinical Trial Design

Secondary endpoint: This was a secondary endpoint of the study.¹¹ These results should be interpreted within the context of the study design, which was not powered to detect a difference in this endpoint. Therefore, the ability to interpret the P value as significant is reduced.

References

Horizant^® [prescribing information]. Woburn, MA: Azurity Pharmaceuticals, Inc; 2022.
Cundy KC, Sastry S, Luo W, et al. Clinical pharmacokinetics of XP13512, a novel transported prodrug of gabapentin. J Clin Pharmacol. 2008;48(12):1378-1388.
Gralise [prescribing information]. Morristown, NJ: Almatica Pharma LLC.
Neurontin [prescribing information]. New York, NY: Parke-Davis Division of Pfizer Inc.
American Academy of Sleep Medicine. Treatment of Restless Legs Syndrome and Periodic Limb Movement Disorder. Published January 13, 2024. Accessed December 18, 2024. chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://aasm.org/wp-content/uploads/2024/03/Treatment-of-RLS-and-PLMD-CPG.pdf
Food and Drug Administration. Orange Book: approved drug products with therapeutic equivalence evaluations [gabapentin enacarbil]. Accessed July 28, 2022. https://www.accessdata.fda.gov/scripts/cder/ob/index.cfm
Lal R, Ellenbogen A, Gidal B. Interindividual variability in the bioavailability of gabapentin enacarbil extended release in healthy adults: an analysis of data from 6 phase I studies. Ther Drug Monit. 2022;44(3):448-454.
Lee DO, Ziman RB, Perkins AT, et al; XP053 Study Group. A randomized, double-blind, placebo-controlled study to assess the efficacy and tolerability of gabapentin enacarbil in subjects with restless legs syndrome. J Clin Sleep Med. 2011;7(3):282-292.

National Heart, Lung and Blood Institute Biologic Specimen and Data Repository. Restless Legs Syndrome Rating Scale. Accessed July 28, 2022. https://biolincc.nhlbi.nih.gov/media/studies/masm/IRLS.pdf?link_time=2019-07-07_21:09:19.282153
Data on file. Azurity Pharmaceuticals, Inc.
Zhang L, Rainka M, Freeman R, et al. 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). J Pain. 2013;14(6):590-603.

Reduction of 24-hour average pain score during week 1 up-titration vs placebo¹⁰

PHN clinical trial design^1,11

The efficacy and tolerability of Horizant® were evaluated in a randomized, double-blind, placebo-controlled study in adults with PHN. Patients (N=376) were required to have a baseline 24-hour average pain score of ≥4 on an 11-point pain intensity numerical rating scale, ranging from 0 (no pain) to 10 (worst possible pain). Patients were excluded if, over the past year, they had certain psychiatric comorbidities, a history of drug or alcohol abuse, hepatic or renal impairment (creatinine clearance <60 mL/min or hemodialysis), abnormal electrocardiogram, uncontrolled hypertension, or a seizure disorder requiring medication.

The primary endpoint was change from baseline to end of maintenance treatment in mean 24-hour average pain intensity score. Additional endpoints included proportion of patients achieving a percent reduction in pain score from baseline and daytime/nighttime worst pain intensity.

Reduction of 24-hour average pain score during week 1 up-titration vs placebo10

References

Reduction of 24-hour average pain score during week 1 up-titration vs placebo10

PHN clinical trial design1,11

Reduction of 24-hour average pain score during week 1 up-titration vs placebo¹⁰

Reduction of 24-hour average pain score during week 1 up-titration vs placebo¹⁰

PHN clinical trial design^1,11