A Phase 2 interventional study of Placebo and LX9211 in Postherpetic Neuralgia, sponsored by Lexicon Pharmaceuticals. Completed at 32 sites in 3 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-02-13.
Sponsored by Lexicon Pharmaceuticals · Phase 2, Interventional, and Treatment
Among 60 studies in Neuralgia, Postherpetic with a site in United States — 4 open to participants now, 5 under way, none of them phase 3. Neuralgia, Postherpetic · United States.
Among the 60 studies in Neuralgia, Postherpetic with a site in United States, this one is the 30th largest by enrollment of the 56 interventional ones that give a count, is the only one that started in 2020, is one of 33 in phase 2, and was the 56th registered.
196 studies on the registry are indexed under Neuralgia, Postherpetic; 28 are open to participants now.
Browse Neuralgia, Postherpetic studies →4 of the 60 studies in Neuralgia, Postherpetic with a site in United States are open now. Recruiting first, the newest first:
Brown University · Sites in United States
University of California, San Francisco · Sites in United States
University of Minnesota · Sites in United States
Neurodawn Pharmaceutical Co., Ltd. · Sites in United States
A study can be open while its sites in United States have not opened yet or have stopped. Only those recruiting at a site in United States →
Of the 18 Neuralgia, Postherpetic studies recruiting now, 8 (44%) set no upper age limit and 5 (28%) stop at 75 or younger; 0 take children under 18; 2 take healthy volunteers.
This study: 18 Years and older · all sexes · no healthy volunteers.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
60 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 1 5 · Phase 2 35 · Phase 3 9 · Phase 4 4
First in 1993; this study’s year is marked. 1 started in 2020.
This study's enrollment of 79 is below the median of 94 across 162 interventional studies indexed under Neuralgia, Postherpetic.
Median enrollment 93 across the 56 interventional studies, 201 across the 3 observational. Of the 51 that completed or were terminated, 22 (43%) have results posted.
This tab as a report to print or save as PDF → With an account.
46 of 60 have an industry lead sponsor. The 10 most frequent:
Lexicon Pharmaceuticals is the lead sponsor of 61 studies on the registry; none are open to participants now.
Of its 18 completed or terminated interventional studies of FDA-regulated products, 15 (83%) have results posted.
Lexicon Pharmaceuticals has 1 study filed under Neuralgia, Postherpetic — fewer than ten, so there is no comparison to draw.
1 of the studies in Neuralgia, Postherpetic with a site in United States that are under way reach primary completion within a year, 0 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT05593237University of California, San FranciscoTranscranial Magnetic Stimulation for Chronic Neuropathic Pain | 2026-12-30 |
Among the 60 studies in Neuralgia, Postherpetic with a site in United States, from their registry updates:
This tab as a report to print or save as PDF → With an account.
Evaluation of the efficacy of LX9211 compared to placebo in reducing pain related to postherpetic neuralgia over an 11 week assessment period.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Following a 2-week Single-blind Run-in period, participants will receive a single loading dose of matching-placebo to LX9211 tablet, orally, on Day 1 and maintenance doses, orally, once daily from Day 2 to Week 6.
Drug: Placebo
Following a 2-week Single-blind Run-in period, participants will receive a single loading dose of 200 milligrams (mg) tablet, orally, on Day 1 and maintenance doses of 20 mg, orally, once daily from Day 2 to Week 6.
Drug: LX9211
LX9211 matching-placebo, tablets will be administered orally.
LX9211 tablets will be administered orally.
Change From Baseline (Week 2 of the Run-in Period) in Average Daily Pain Score (ADPS)
ADPS is based on question 5 of Zoster Brief Pain Inventory (ZBPI) and assessed on an 11-point numerical rating scale where, 0 = No Pain to 10 = pain as bad as you can imagine. Higher ADPS scores indicates a worse outcome. Negative change from baseline indicates no pain.
Time frame: Baseline (Week 2 of the Run-in period) to Week 6
Change From Baseline in Pain Interfering With Sleep Based on Question 9F of the ZBPI at Week 6
Pain interfering with sleep is based on Question 9F of the ZBPI "Indicate the one number that describes how, in the past 24-hours shingles pain has interfered with your: Sleep; 0 = does not interfere to 10 = Completely interferes. Higher the number, the worsening of sleep due to pain interference. Negative change from baseline indicates no interference in sleep. Pain interfering with sleep was based on the daily pain diary data based on Q 9F of the ZBPI.
Time frame: Baseline to Week 6
Percentage of Participants With ≥30% Reduction in Pain Intensity in ADPS From Baseline at Week 6
ADPS is based on question 5 of Zoster Brief Pain Inventory (ZBPI) and assessed on an 11-point numerical rating scale where, 0 = No Pain to 10 = pain as bad as you can imagine. Higher ADPS scores indicated a worse outcome.
Time frame: Baseline to Week 6
Percentage of Participants With ≥50% Reduction in Pain Intensity in ADPS From Baseline at Week 6
ADPS is based on question 5 of ZBPI and assessed on an 11-point numerical rating scale where, 0 = No Pain to 10 = pain as bad as you can imagine. Higher ADPS scores indicated a worse outcome.
Time frame: Baseline to Week 6
Change From Baseline in Interference in General Activity, Mood, Walking Ability, Normal Work, Relations With Other People, Sleep, and Enjoyment of Life Interference Based on the Questions 9A-G of the ZBPI
The ZBPI, a 9-item questionnaire, assesses the severity of pain and its impact on functioning in participants with postherpetic neuralgia (PHN). Each question concerning daily activity (General Activity, Mood, Walking Ability, Normal Work, Relations With Other People, Sleep, and Enjoyment of Life) was scored on a scale from 0 to 10, where 0 indicated no interference and 10 indicated complete interference. Higher ZBPI score indicates a worse outcome. Negative change from baseline indicates no interference in all daily activities. The pain interference at Week 6 in this outcome measure was based on data collected on the ZBPI administered at the Week 6 in-person clinic visit.
Time frame: Baseline to Week 6
Number of Participants Discontinuing Treatment Due to Lack of Efficacy Defined as Increase in ADPS From Baseline of ≥30% Based on Question 5 of the ZBPI
ADPS is based on question 5 of ZBPI and assessed on an 11-point numerical rating scale where, 0 = No Pain to 10 = pain as bad as you can imagine.
Time frame: Baseline to Week 6
Patient Global Impression of Change (PGIC) at Week 6
PGIC is assessed on a 7-point rating scale where 1= very much improved to 7 = very much worse. Higher scores indicate worse outcomes.
Time frame: Baseline to Week 6
Time to Loss of Efficacy From Week 6 to Week 11 Among Participants Achieving ≥30% Reduction in Pain Intensity in ADPS Based on Question 5 of the ZBPI.
ADPS is based on question 5 of ZBPI and assessed on an 11-point numerical rating scale where, 0 = No Pain to 10 = pain as bad as you can imagine.
Time frame: Week 6 to Week 11
Number of Participants With Treatment-emergent Adverse Events (TEAEs)
Adverse Events (AEs) are defined as any sign, symptom, or diagnosis/disease that is unfavorable or unintended, that is new, or if pre-existing, worsens in participants administered a pharmaceutical product and that does not necessarily have a causal relationship with this treatment. Treatment-emergent AEs are defined as any AEs reported after the first dose of double-blind study medication on study Day 1.
Time frame: From first dose of study drug up to end of double-blind treatment period (up to Week 6) and end of single-blind treatment period (up to Week 11)
Participants took part in the study at multiple investigative sites from 10 Dec 2020 to 28 Dec 2022.
| Milestone | Placebo | LX9211 |
|---|---|---|
| Started | 41 | 38 |
| Completed | 34 | 21 |
| Not completed | 7 | 17 |
| Withdrew: Adverse event | 4 | 13 |
| Withdrew: Withdrawal by subject | 1 | 2 |
| Withdrew: Lack of efficacy | 1 | 0 |
| Withdrew: Reason not specified | 1 | 2 |
ADPS is based on question 5 of Zoster Brief Pain Inventory (ZBPI) and assessed on an 11-point numerical rating scale where, 0 = No Pain to 10 = pain as bad as you can imagine. Higher ADPS scores indicates a worse outcome. Negative change from baseline indicates no pain.
| score on a scale | Placebo | LX9211 |
|---|---|---|
| Change From Baseline (Week 2 of the Run-in Period) in Average Daily Pain Score (ADPS) | -1.62 ± 0.360 | -2.42 ± 0.397 |
Pain interfering with sleep is based on Question 9F of the ZBPI "Indicate the one number that describes how, in the past 24-hours shingles pain has interfered with your: Sleep; 0 = does not interfere to 10 = Completely interferes. Higher the number, the worsening of sleep due to pain interference. Negative change from baseline indicates no interference in sleep. Pain interfering with sleep was based on the daily pain diary data based on Q 9F of the ZBPI.
| score on a scale | Placebo | LX9211 |
|---|---|---|
| Change From Baseline in Pain Interfering With Sleep Based on Question 9F of the ZBPI at Week 6 | -1.43 ± 0.323 | -2.04 ± 0.364 |
ADPS is based on question 5 of Zoster Brief Pain Inventory (ZBPI) and assessed on an 11-point numerical rating scale where, 0 = No Pain to 10 = pain as bad as you can imagine. Higher ADPS scores indicated a worse outcome.
| percentage of participants | Placebo | LX9211 |
|---|---|---|
| Percentage of Participants With ≥30% Reduction in Pain Intensity in ADPS From Baseline at Week 6 | 34.15 | 42.11 |
ADPS is based on question 5 of ZBPI and assessed on an 11-point numerical rating scale where, 0 = No Pain to 10 = pain as bad as you can imagine. Higher ADPS scores indicated a worse outcome.
| percentage of participants | Placebo | LX9211 |
|---|---|---|
| Percentage of Participants With ≥50% Reduction in Pain Intensity in ADPS From Baseline at Week 6 | 19.51 | 23.68 |
The ZBPI, a 9-item questionnaire, assesses the severity of pain and its impact on functioning in participants with postherpetic neuralgia (PHN). Each question concerning daily activity (General Activity, Mood, Walking Ability, Normal Work, Relations With Other People, Sleep, and Enjoyment of Life) was scored on a scale from 0 to 10, where 0 indicated no interference and 10 indicated complete interference. Higher ZBPI score indicates a worse outcome. Negative change from baseline indicates no interference in all daily activities. The pain interference at Week 6 in this outcome measure was based on data collected on the ZBPI administered at the Week 6 in-person clinic visit.
| score on a scale | Placebo | LX9211 |
|---|---|---|
| General Activity: Change at Week 6 | -0.52 ± 0.392 | -1.75 ± 0.417 |
| Mood: Change at Week 6 | -1.52 ± 0.407 | -2.36 ± 0.435 |
| Walking Ability: Change at Week 6 | -0.28 ± 0.373 | -0.72 ± 0.391 |
| Normal Work: Change at Week 6 | -0.61 ± 0.383 | -1.28 ± 0.397 |
| Relations With Other People: Change at Week 6 | -0.89 ± 0.381 | -1.27 ± 0.400 |
| Relations With Sleep: Change at Week 6 | -1.61 ± 0.370 | -1.66 ± 0.382 |
| Enjoyment of Life: Change at Week 6 | -1.13 ± 0.405 | -1.93 ± 0.435 |
ADPS is based on question 5 of ZBPI and assessed on an 11-point numerical rating scale where, 0 = No Pain to 10 = pain as bad as you can imagine.
| Participants | Placebo | LX9211 |
|---|---|---|
| Number of Participants Discontinuing Treatment Due to Lack of Efficacy Defined as Increase in ADPS From Baseline of ≥30% Based on Question 5 of the ZBPI | 1 | 0 |
PGIC is assessed on a 7-point rating scale where 1= very much improved to 7 = very much worse. Higher scores indicate worse outcomes.
| score on a scale | Placebo | LX9211 |
|---|---|---|
| Patient Global Impression of Change (PGIC) at Week 6 | 3.06 ± 0.222 | 2.65 ± 0.265 |
ADPS is based on question 5 of ZBPI and assessed on an 11-point numerical rating scale where, 0 = No Pain to 10 = pain as bad as you can imagine.
| weeks | Placebo | LX9211 |
|---|---|---|
| Time to Loss of Efficacy From Week 6 to Week 11 Among Participants Achieving ≥30% Reduction in Pain Intensity in ADPS Based on Question 5 of the ZBPI. | NA (NA to NA) | NA (NA to NA) |
Adverse Events (AEs) are defined as any sign, symptom, or diagnosis/disease that is unfavorable or unintended, that is new, or if pre-existing, worsens in participants administered a pharmaceutical product and that does not necessarily have a causal relationship with this treatment. Treatment-emergent AEs are defined as any AEs reported after the first dose of double-blind study medication on study Day 1.
| Participants | Placebo (Double-blind Treatment Period) | LX9211 (Double-blind Treatment Period) | Placebo (Single-blind Placebo Safety Follow-up Period) | LX9211 (Single-blind Placebo Safety Follow-up Period) |
|---|---|---|---|---|
| Number of Participants With Treatment-emergent Adverse Events (TEAEs) | 13 | 24 | 9 | 5 |
Collected over From first dose of study drug up to end of double-blind treatment period (up to Week 6) and end of single-blind treatment period (up to Week 11). Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Placebo (Double-blind Treatment Period) | 0/41 (0%) | 0/41 (0%) | 6/41 (14.6%) |
| LX9211 (Double-blind Treatment Period) | 0/38 (0%) | 0/38 (0%) | 24/38 (63.2%) |
| Placebo (Single-blind Placebo Safety Follow-up Period) | 0/38 (0%) | 0/38 (0%) | 2/38 (5.3%) |
| LX9211 (Single-blind Placebo Safety Follow-up Period) | 0/31 (0%) | 0/31 (0%) | 1/31 (3.2%) |
| Event | Placebo (Double-blind Treatment Period) | LX9211 (Double-blind Treatment Period) | Placebo (Single-blind Placebo Safety Follow-up Period) | LX9211 (Single-blind Placebo Safety Follow-up Period) |
|---|---|---|---|---|
| DizzinessNervous system disorders | 2/41 | 11/38 | 0/38 | 0/31 |
| ConstipationGastrointestinal disorders | 0/41 | 4/38 | 0/38 | 0/31 |
| HeadacheNervous system disorders | 2/41 | 4/38 | 1/38 | 1/31 |
| NauseaGastrointestinal disorders | 0/41 | 3/38 | 0/38 | 1/31 |
| Urinary tract infectionInfections and infestations | 2/41 | 3/38 | 2/38 | 1/31 |
| DiarrheaGastrointestinal disorders | 3/41 | 0/38 | 0/38 | 0/31 |
| VertigoEar and labyrinth disorders | 0/41 | 2/38 | 0/38 | 0/31 |
| Dry mouthGastrointestinal disorders | 0/41 | 2/38 | 0/38 | 0/31 |
| Balance disorderNervous system disorders | 0/41 | 2/38 | 0/38 | 0/31 |
| SomnolenceNervous system disorders | 0/41 | 2/38 | 0/38 | 0/31 |
Modified Intent-to-Treat (mITT) population included all randomized participants who had taken at least 1 dose of study drug.
| Age, Continuous(years) | Placebo | LX9211 | Total |
|---|---|---|---|
| Mean | 63.6 ± 12.5 | 65.4 ± 11.7 | 64.5 ± 12.1 |
| Sex: Female, Male(Participants) | Placebo | LX9211 | Total |
|---|---|---|---|
| Female | 24 | 23 | 47 |
| Male | 17 | 15 | 32 |
| Ethnicity (NIH/OMB)(Participants) | Placebo | LX9211 | Total |
|---|---|---|---|
| Hispanic or Latino | 12 | 11 | 23 |
| Not Hispanic or Latino | 29 | 27 | 56 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Race (NIH/OMB)(Participants) | Placebo | LX9211 | Total |
|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 |
| Asian | 0 | 0 | 0 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 |
| Black or African American | 2 | 0 | 2 |
| White | 39 | 37 | 76 |
| More than one race | 0 | 0 | 0 |
| Unknown or Not Reported | 0 | 1 | 1 |
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: Yes — Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants.
Supporting information: Study protocol, Statistical analysis plan, Clinical study report
Ran from Dec 2020 to primary completion in Nov 2022, 23 months.
Results were first posted in Feb 2026, 3 years 2 months after primary completion. A results delay was requested in Nov 2023.
Of 12 phase 2 interventional studies under Neuralgia, Postherpetic, half reached primary completion within 12 months of starting (the median), counting those still running; a quarter within 9 and three quarters within 17. This study's 23 months is above that.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Jan 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Pilavapadin