Brain Stimulation for Postherpetic Neuralgia: A Randomized Sham-Controlled Trial (PHN)

Huazhong University of Science and Technology

Status: Not yet enrolling

Conditions: Postherpetic Neuralgia

Treatments: Device: Sham Non-invasive transcranial stimulation; Device: Non-invasive transcranial stimulation

Study type: Interventional

Funder types: Other

Identifiers

NCT07352553

TJ-IRB202512160

Details and patient eligibility

About

Pharmacotherapy is the cornerstone of Postherpetic Neuralgia (PHN) management. First-line treatments for PHN include antiviral agents (e.g., acyclovir, valacyclovir, famciclovir, and brivudine), centrally acting antiepileptic drugs (pregabalin and gabapentin), antidepressants (duloxetine and venlafaxine), and peripherally acting sodium-channel blockers (lidocaine patches).

In recent years, substantial progress has been made in the prevention and treatment of PHN, including early and active antiviral therapy (acyclovir, valacyclovir, famciclovir, brivudine, etc.), analgesic therapy (calcium-channel modulators such as pregabalin and gabapentin; tricyclic antidepressants such as amitriptyline; and opioid analgesics), interventional procedures (e.g., radiofrequency modulation and spinal cord stimulation), and vaccination. Nevertheless, clinical outcomes remain unsatisfactory, with the incidence of refractory PHN still exceeding 50%. Adverse effects associated with certain first- and second-line medications (such as antidepressants and anticonvulsants), as well as the potential risk of opioid dependence, markedly reduce treatment adherence. This situation has compelled clinicians to continually seek new and effective therapeutic approaches for PHN.

Non-invasive transcranial stimulation, as an emerging noninvasive neuromodulation technique, enables targeted modulation of deep brain structures. Animal studies have demonstrated that it can noninvasively regulate neuronal firing in deep regions and induce long-term plasticity, while offering relatively high spatial selectivity and tissue penetration. These features suggest broad clinical potential in chronic pain and affective disorders.

Enrollment: 94 estimated patients

Sex: All

Ages: 18 to 80 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age ≥ 18 years.
• Diagnosis of postherpetic neuralgia (PHN) with disease duration ≥ 3 months.
• NRS pain score ≥ 4.
• Willing to receive the intervention and able to provide written informed consent.

Exclusion criteria

• Contraindications to electrical stimulation (e.g., intracranial metal implants, cardiac pacemaker).
• History of epilepsy, severe psychiatric disorder, or cognitive impairment.
• Pregnant or breastfeeding women.
• Unable to comply with the intervention procedures and follow-up assessments.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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94 participants in 2 patient groups

Brain Stimulation + Usual Care

Experimental group

Description:

Participants receive brain stimulation in addition to usual pharmacological care for postherpetic neuralgia. Brain stimulation is delivered once daily for 30 minutes for 10 consecutive days.

Treatment:

Device: Non-invasive transcranial stimulation

Sham Stimulation + Usual Care

Sham Comparator group

Description:

Participants receive sham stimulation in addition to usual pharmacological care. Electrodes are applied once daily for 30 minutes for 10 consecutive days; after an initial brief stimulation to mimic sensation, the output is turned off.

Treatment:

Device: Sham Non-invasive transcranial stimulation