The Analgesic Efficacy and Safety of Mirogabalin in Patients With Herpes Zoster

The Analgesic Efficacy and Safety of Oral Medications (Mirogabalin) in Patients With Herpes Zoster

Herpes zoster (HZ) is characterized by a painful dermatomal rash and significantly affects quality of life, with acute pain increasing the risk of postherpetic neuralgia. Although early antiviral therapy limits viral replication, its analgesic effect is insufficient, and many patients experience inadequate relief despite stepwise use of non-opioids and opioids. Gabapentinoids such as gabapentin and pregabalin are recommended adjuncts, but their efficacy in acute HZ is inconsistent and often accompanied by adverse effects that limit tolerability. Mirogabalin, a newer gabapentinoid approved for peripheral neuropathic pain, has higher affinity and slower dissociation from the α2δ-1 subunit, suggesting stronger analgesia with fewer central side effects. However, its role in managing acute HZ pain remains unknown. We therefore hypothesize that adding mirogabalin to conventional therapy will provide superior pain relief compared with standard treatment alone, and propose a prospective, randomized, controlled, open-label, blinded-endpoint trial to evaluate this.

Study Overview

• Status: Recruiting
• Conditions: Pain; Herpes Zoster; Mirogabalin
• Intervention / Treatment: Drug: Conventional therapy; Drug: Mirogabalin combined conventional therapy

• Study Type: Interventional
• Enrollment (Estimated): 750
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Fang Luo; Phone Number: 13611326978; Email: 13611326978@163.com

Study Locations

• China
  • Beijing, China
    • Recruiting
    • Beijing Tiantan Hospital, Beijing, Beijing 100070
    • Contact: Fang Luo; Phone Number: 13611326978; Email: 13611326978@163.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• 1. Ages more than 18 years;
• 2. Patients with onset of HZ rash less than 30 days;
• 3. Experiencing moderate to severe HZ pain with an average pain score of at least 4 on a Numeric Rating Scale (NRS, 0 = no pain, 10 = worst possible pain);
• 4. Aspartate aminotransferase and alanine aminotransferase levels less than twice the upper limit of normal;
• 5. Estimated glomerular filtration rate of 30 mL/min per 1.73 m2 or higher;
• 6. Willing to sign the informed consent form and possessing sufficient cognitive and language abilities to comply with all the study requirements.

Exclusion Criteria:

• 1. History of taking gabapentin or pregabalin;
• 2. Patients with evidence of cutaneous or visceral dissemination of HZ infection (cutaneous dissemination is defined as more than 20 discrete lesions outside adjacent dermatomes) or ocular involvement of HZ;
• 3. History of intolerance or hypersensitivity to any active components or excipient of the mirogabalin;
• 4. History of systemic immune diseases, organ transplantation, or cancers;
• 5. Pregnancy or breastfeeding;
• 6. Suffering from acute or chronic pain disorders other than HZ;
• 7. Patients with severe psychiatric disorders, or cognitive impairment.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Control group	Drug: Conventional therapy; In the conventional therapy group, treatments will include NSAIDs, opioids, antiviral drugs and so on.
Experimental: Mirogabalin group	Drug: Mirogabalin combined conventional therapy; In the mirogabalin group, participants will receive mirogabalin in addition to the same standardized conventional treatment used in the control group, including antiviral therapy, non-opioid analgesics, and opioid analgesics when clinically indicated. Mirogabalin (Mirogabalin Besylate, Daiichi Sankyo Co., ltd, Japan) will be initiated 5 mg twice daily. If the patient's NRS score reaches 0 within the first week, mirogabalin will be discontinued. Otherwise, the dose will be increased to 10 mg twice daily during the second week. If the NRS score reaches 0 within the second week, the dose will be reduced to 5 mg twice daily for 1 week and then discontinued. If pain persists, the dose will be further increased to 15 mg twice daily and maintained until an NRS score of 0 is achieved or until the 90 days after rash onset.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
the average numeric rating scale score over the past 24 hours, rated each morning upon awakening and average over 7 days at week 4	The numeric rating scale (NRS) score is a way to quantify the degree of subjective feelings such as pain using numbers. Generally, 0 represents no pain, and 10 represents the most severe pain. A higher score indicates more severe pain.	At week 4 after randomization

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The worst numeric rating scale score	The numeric rating scale (NRS) score is a way to quantify the degree of subjective feelings such as pain using numbers. Generally, 0 represents no pain, and 10 represents the most severe pain. A higher score indicates more severe pain.	at weeks 1, 2, 4, 8, 12, 24, and 52 after randomization
Proportion of Patients Achieving Pain Reduction	The proportion of patients achieving a ≥ 50% and ≥ 30% reduction in mean baseline pain intensity	at weeks 1, 2, 4, 8, 12, 24, and 52 after randomization
Proportion of patients developing postherpetic neuralgia	postherpetic neuralgia is defined as persistent pain in the affected dermatome for at least 90 days after rash onset, with an average pain intensity of ≥3 on the NRS	At least 90 days after rash onset
The type of analgesics and average weekly consumption per analgesics		at weeks 1, 2, 4, 8, 12, 24, and 52 after randomization
Herpes Zoster Severity of Illness (HZSOI) Index	The HZSOI is a severity-by-duration measure of overall pain burden associated with HZ and is typically calculated as the area under the curve of the worst pain scores over a defined period after rash onset.	from rash onset to day 90
The 12-item Short-Form Health Survey (SF-12) score	The SF-12 score assesses the health-related quality of life, capturing preferences across various health states. It assesses 8 dimensions: physical functioning, physical role limitations due to physical health, bodily pain, general health, vitality, social functioning, emotional role limitations due to emotional problems, and mental health. Scores range from 0 to 100 for each dimension, with higher scores indicating better health status.	at weeks 4, 8, 12, 24, and 52 after randomization.
The Medical Outcomes Study Sleep Scale (MOS)	The MOS is a questionnaire comprising 12 items that assess various aspects of sleep using a 6-point ordinal scale (1 indicating permanence and 6 indicating absence).	at weeks 4, 8, 12, 24, and 52 after randomization.
Neuropathic Pain Scale	Neuropathic pain characteristics will be assessed using the Neuropathic Pain Scale in participants with developing PHN. The Neuropathic Pain Scale consists of 10 numeric rating items, each scored from 0 to 10, with higher scores indicating greater neuropathic pain severity. The scale assesses pain intensity, unpleasantness, and 8 specific pain qualities, including sharp, hot, dull, cold, sensitive, itchy, deep, and surface pain.	at or after 90 days following rash onset
Adverse events	The incidence and proportion of AEs will be recorded and categorized as mild, moderate, severe, or life-threatening. AEs are defined as events that arise during treatment, were absent before treatment, or worsen relative to the pretreatment state.	Through study completion, an average of 52 weeks

Collaborators and Investigators

• Sponsor: Beijing Tiantan Hospital
• Collaborators: The Second Hospital of Hebei Medical University; Second Hospital of Shanxi Medical University

Publications and helpful links

Helpful Links

• Rosamilia LL. Herpes Zoster Presentation, Management, and Prevention: A Modern Case-Based Review. Am J Clin Dermatol. 2020;21(1):97-107.
• Liu Y, Xiao S, Li J, Long X, Zhang Y, Li X. A Network Meta-Analysis of Randomized Clinical Trials to Assess the Efficacy and Safety of Antiviral Agents for Immunocompetent Patients with Herpes Zoster-Associated Pain. Pain Physician. 2023;26(4):337-46.
• Domon Y, Arakawa N, Inoue T, Matsuda F, Takahashi M, Yamamura N, et al. Binding Characteristics and Analgesic Effects of Mirogabalin, a Novel Ligand for the α2δ Subunit of Voltage-Gated Calcium Channels. J Pharmacol Exp Ther. 2018;365(3):573-82.

Study record dates

Study Major Dates

• Study Start (Actual): December 15, 2025
• Primary Completion (Estimated): October 31, 2027
• Study Completion (Estimated): December 31, 2027

Study Registration Dates

• First Submitted: December 14, 2025
• First Submitted That Met QC Criteria: December 14, 2025
• First Posted (Actual): December 29, 2025

Study Record Updates

• Last Update Posted (Actual): March 19, 2026
• Last Update Submitted That Met QC Criteria: March 17, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Varicella Zoster Virus Infection; Neurologic Manifestations; Infections; Virus Diseases; DNA Virus Infections; Herpesviridae Infections; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Pain; Herpes Zoster
• Other Study ID Numbers: KY2025-369-02-1

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Individual participant data that underlie the results reported in this article, after de-identification (text, tables, figures and appendices) are available. Derived data supporting the findings of this study are available from the corresponding author Fang Luo on request.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No