Neuropathic PainDRG-SHAMNCT07170722
Sub-threshold DRG Stimulation vs Sham in Established Responders
A study testing Subtreshhold DRG-S in people with Neuropathic Pain and Complex Regional Pain Syndromes (CRPS), run by Umeå University at 1 site in Sweden.
Trial summary
The goal of this clinical trial is to learn if sub-threshold dorsal root ganglion (DRG) stimulation provides pain relief beyond placebo in adults with chronic neuropathic pain who already have an implanted DRG stimulator. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Neuropathic Pain, Complex Regional Pain Syndromes (CRPS), Causalgia
- What is being tested?
- Subtreshhold DRG-S
- Type of treatment
- Medical device
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 20 participants
- Where
- 1 siteSweden
- Study dates
- 1 Sep 2025to 30 Nov 2025
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Adults, age 18 years or older
- Implanted with a dorsal root ganglion (DRG) stimulator for chronic neuropathic pain
- Have experienced at least 50% reduction in pain for 3 months or longer on standard DRG therapy
- Stable pain medication regimen for at least 4 weeks before enrollment
- Able and willing to complete electronic diaries and attend study visits
Who cannot join
- Active infection or wound complication at the stimulator implant site
- Significant psychiatric illness (for example, uncontrolled depression or psychosis)
- Planned surgery, device reprogramming, or medication changes during the study period
- Currently pregnant or breastfeeding
- Occurrence of any adverse event that meets predefined withdrawal criteria during the study (such as intolerable pain or device-related complications)
Trial locations and contacts
1 site in 1 country.
Sweden1 site
Neurokirurgiska kliniken. Neuromodulationsenheten
Umeå, Västerbotten County, 90185
About this study
Official title: Efficacy of Sub-Threshold Dorsal Root Ganglion (DRG) Stimulation Versus Sham in Established Responders: A Randomised, Double-Blind, Two-Period Crossover Trial
The goal of this clinical trial is to learn if sub-threshold dorsal root ganglion (DRG) stimulation provides pain relief beyond placebo in adults with chronic neuropathic pain who already have an implanted DRG stimulator. The main questions it aims to answer are:
- Does sub-threshold DRG stimulation reduce daily pain intensity compared with sham stimulation?
- How does sub-threshold stimulation affect sleep, mood, and daily activity?
Read more
Researchers will compare active sub-threshold DRG stimulation to sham (device switched off) to see if stimulation has a genuine effect on pain and wellbeing.
Participants will:
- Be randomly assigned to receive either active sub-threshold DRG stimulation or sham stimulation for 5 days, followed by the opposite condition for another 5 days.
- Complete short electronic diaries twice daily about their pain, sleep, mood, and activity.
- Attend study visits for safety checks and assessments.
Read the detailed description
Neuropathic pain is a chronic condition that affects 6-10% of adults and is often resistant to conventional drug therapy. The dorsal root ganglion (DRG) has emerged as an important therapeutic target, as abnormal firing in DRG neurons contributes to peripheral and central sensitization. DRG stimulation (DRGS) delivers mild electrical pulses through implanted leads placed near the DRG. Compared with traditional spinal cord stimulation, DRGS provides highly targeted pain relief with fewer unwanted sensations.
Over the past decade, DRGS has become an established treatment for conditions such as complex regional pain syndrome (CRPS), causalgia, chronic low back pain, and post-surgical neuropathic pain. Modern programming favors sub-threshold settings, in which stimulation is delivered below the level that causes tingling sensations (paresthesias). Although widely adopted, the specific contribution of sub-threshold stimulation has never been confirmed in a sham-controlled trial.
This study is the first randomized, double-blind, sham-controlled trial to directly evaluate whether sub-threshold DRG stimulation provides pain relief beyond placebo. Adults with an implanted DRG stimulator who have shown sustained pain relief will be randomized in a two-period crossover design to receive either active sub-threshold stimulation or sham stimulation, each for 5 days, with a washout period in between.
The primary objective is to determine whether sub-threshold DRG stimulation reduces mean daily pain intensity compared with sham. Secondary objectives include assessing sleep quality, mood, daily activity, and safety/tolerability. Exploratory measures include device logs and rescue medication use.
The findings of this trial will provide critical evidence on the efficacy of sub-threshold DRG stimulation, helping to inform clinical guidelines, payer decisions, and neuromodulation programming strategies worldwide.
- Conditions
- Neuropathic Pain, Complex Regional Pain Syndromes (CRPS), Causalgia, Chronic Pain, Low Back Pain, Pelvic Pain
- Being tested
- Subtreshhold DRG-S, Sham
- Keywords
- Dorsal Root Ganglion Stimulation, DRG Stimulation, Sub-threshold Stimulation, Neuromodulation, Sham-controlled Trial, Randomized Controlled Trial, Crossover Trial, Chronic Neuropathic Pain, Complex Regional Pain Syndrome (CRPS), Failed Back Surgery Syndrome (FBSS), Post-surgical Pain, Post-traumatic Pain, Low Back Pain, Chronic Pelvic Pain
- Medical subject headings
- Neuralgia, Complex Regional Pain Syndromes, Causalgia, Chronic Pain, Low Back Pain, Pelvic Pain, Failed Back Surgery Syndrome, Pain, Postoperative
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Subtreshhold DRG-SDevice
Continuous electrical stimulation delivered through an implanted DRG neurostimulator. Amplitude is set individually to 80% of each participant's perception threshold, ensuring no paresthesia is produced. Frequency and pulse width remain unchanged from the participant's established therapeutic settings. This sub-threshold programming distinguishes the intervention from suprathreshold (paresthesia-based) DRG stimulation used in earlier studies.
ShamOther
The implanted DRG stimulator remains switched off for the entire 5-day period. Device interrogation logs are masked to maintain blinding. No electrical stimulation is delivered, allowing a placebo-controlled comparison with active sub-threshold stimulation.
| Study group | Role | What they receive |
|---|---|---|
| Subtreshhold DRG-S | Active comparator | Active Sub-threshold DRG Stimulation Participants receive sub-threshold dorsal root ganglion (DRG) stimulation. Device amplitude is individually titrated to 80% of the perception threshold, ensuring no paresthesia is felt. Frequency and pulse width remain unchanged from each participant's established clinical settings. Stimulation is delivered continuously for 5 days. Receives: Device: Subtreshhold DRG-S |
| Sham | Sham comparator | Sham Stimulation Participants receive sham stimulation. The implanted DRG stimulator is switched off, with device interrogation logs masked to maintain blinding. The sham condition lasts for 5 days. Receives: Other: Sham |
What is being measured
The primary outcome is the main question the study is designed to answer.
Average daily pain intensity (Numeric Rating Scale, 0-10)
Self-reported pain intensity recorded twice daily (morning and evening) using an 11-point Numeric Rating Scale (0 = no pain, 10 = worst pain imaginable). Daily scores will be averaged across each treatment and washout period.
Measured: Twice daily (morning and evening) from Day 0 through Day 11 (includes both 5-day treatment periods and the two 24-hour washout periods on Day 0 and Day 6).
Secondary outcomes (4)
Sleep quality (Patient Global Impression of Change, PGIC)
Self-reported sleep quality rated each morning using the Patient Global Impression of Change (PGIC) scale, ranging from 1 = very much worse to 5 = very much improved. Higher scores indicate better sleep.
Measured: Daily in the morning from Day 0 through Day 11.
Mood (Patient Global Impression of Change, PGIC)
Self-reported mood rated each evening using the PGIC scale, ranging from 1 = very much worse to 5 = very much improved. Higher scores indicate better mood.
Measured: Daily in the evening from Day 0 through Day 11.
Daily activity (Patient Global Impression of Change, PGIC)
Self-reported daily activity rated each evening using the PGIC scale, ranging from 1 = very much worse to 5 = very much improved. Higher scores indicate better activity.
Measured: Daily in the evening from Day 0 through Day 11.
Adverse events
Number and type of adverse events, documented with onset, severity, relatedness to treatment, and resolution.
Measured: From day 0 through end of study (day 11).
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted12 Sep 2025
- Study start1 Sep 2025
- Primary completion30 Nov 2025
- Study completion30 Nov 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (6)Papers the sponsor has linked to this study.
- Other trials for Neuropathic PainStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- Randomised, double blinded, sham study
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 20 participants (actual)
Sponsor and investigators
- Lead sponsor
- Umeå University
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Pedram Tabatabaei Tabatabaei, M.D, Ph.D, Principal investigator, Univeristy hospital of northern sweden
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07170722
- Sponsor's protocol ID
- DRG-SHAM-2025
- Acronym
- DRG-SHAM
- Status last verified
- Aug 2025
- First submitted
- 26 Aug 2025
- Last updated
- 5 Dec 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: De-identified individual participant data (IPD) underlying the published results will be made available. This will include outcome data reported in the manuscript. Data will be available beginning 12 months after publication, with no end date. Access will be granted to qualified researchers upon reasonable request, subject to approval of a proposal and completion of a data use agreement. Data and statistical code will also be deposited in an open repository (OSF)
Publications
Huygen FJPM, Kallewaard JW, Nijhuis H, Liem L, Vesper J, Fahey ME, Blomme B, Morgalla MH, Deer TR, Capobianco RA. Effectiveness and Safety of Dorsal Root Ganglion Stimulation for the Treatment of Chronic Pain: A Pooled Analysis. Neuromodulation. 2020 Feb;23(2):213-221. doi: 10.1111/ner.13074. Epub 2019 Nov 15.
PubMed 31730273D'Souza RS, Kubrova E, Her YF, Barman RA, Smith BJ, Alvarez GM, West TE, Abd-Elsayed A. Dorsal Root Ganglion Stimulation for Lower Extremity Neuropathic Pain Syndromes: An Evidence-Based Literature Review. Adv Ther. 2022 Oct;39(10):4440-4473. doi: 10.1007/s12325-022-02244-9. Epub 2022 Aug 22.
PubMed 35994195Deer TR, Levy RM, Kramer J, Poree L, Amirdelfan K, Grigsby E, Staats P, Burton AW, Burgher AH, Obray J, Scowcroft J, Golovac S, Kapural L, Paicius R, Kim C, Pope J, Yearwood T, Samuel S, McRoberts WP, Cassim H, Netherton M, Miller N, Schaufele M, Tavel E, Davis T, Davis K, Johnson L, Mekhail N. Dorsal root ganglion stimulation yielded higher treatment success rate for complex regional pain syndrome and causalgia at 3 and 12 months: a randomized comparative trial. Pain. 2017 Apr;158(4):669-681. doi: 10.1097/j.pain.0000000000000814.
PubMed 28030470Chapman KB, Sayed D, Lamer T, Hunter C, Weisbein J, Patel KV, Dickerson D, Hagedorn JM, Lee DW, Amirdelfan K, Deer T, Chakravarthy K. Best Practices for Dorsal Root Ganglion Stimulation for Chronic Pain: Guidelines from the American Society of Pain and Neuroscience. J Pain Res. 2023 Mar 14;16:839-879. doi: 10.2147/JPR.S364370. eCollection 2023.
PubMed 36942306Piedade GS, Gillner S, McPhillips PS, Vesper J, Slotty PJ. Effect of low-frequency dorsal root ganglion stimulation in the treatment of chronic pain. Acta Neurochir (Wien). 2023 Apr;165(4):947-952. doi: 10.1007/s00701-023-05500-1. Epub 2023 Jan 27.
PubMed 36705762Tabatabaei P, Wanman J, Awad A, Eriksson M, Salomonsson J, Bredemo L, Sjoberg R, Hariz MI, Blomstedt P. Subperception dorsal root ganglion stimulation versus sham stimulation in established responders: a randomized, double-blind crossover clinical trial. Reg Anesth Pain Med. 2026 May 13:rapm-2026-107906. doi: 10.1136/rapm-2026-107906. Online ahead of print.
PubMed 42128597
Study at a glance
From the registry record, last updated by the sponsor on 5 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Efficacy of Sub-Threshold Dorsal Root Ganglion (DRG) Stimulation Versus Sham in Established Responders: A Randomised, Double-Blind, Two-Period Crossover Trial
- ClinicalTrials.gov ID
- NCT07170722
- Acronym / sponsor ID
- DRG-SHAM / DRG-SHAM-2025
- Conditions
- Neuropathic Pain, Complex Regional Pain Syndromes (CRPS), Causalgia, Chronic Pain, Low Back Pain, Pelvic Pain
- Keywords
- Dorsal Root Ganglion Stimulation, DRG Stimulation, Sub-threshold Stimulation, Neuromodulation, Sham-controlled Trial, Randomized Controlled Trial, Crossover Trial, Chronic Neuropathic Pain
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 20 participants (actual)
- Lead sponsor
- Umeå UniversityUniversity, hospital or other
- Study start
- 1 Sep 2025 (actual)
- Primary completion
- 30 Nov 2025 (actual)
- Study completion
- 30 Nov 2025 (actual)
- First posted
- 12 Sep 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this clinical trial is to learn if sub-threshold dorsal root ganglion (DRG) stimulation provides pain relief beyond placebo in adults with chronic neuropathic pain who already have an implanted DRG stimulator. The main questions it aims to answer are:
- Does sub-threshold DRG stimulation reduce daily pain intensity compared with sham stimulation?
- How does sub-threshold stimulation affect sleep, mood, and daily activity?
Researchers will compare active sub-threshold DRG stimulation to sham (device switched off) to see if stimulation has a genuine effect on pain and wellbeing.
Participants will:
- Be randomly assigned to receive either active sub-threshold DRG stimulation or sham stimulation for 5 days, followed by the opposite condition for another 5 days.
- Complete short electronic diaries twice daily about their pain, sleep, mood, and activity.
- Attend study visits for safety checks and assessments.
Detailed description
Neuropathic pain is a chronic condition that affects 6-10% of adults and is often resistant to conventional drug therapy. The dorsal root ganglion (DRG) has emerged as an important therapeutic target, as abnormal firing in DRG neurons contributes to peripheral and central sensitization. DRG stimulation (DRGS) delivers mild electrical pulses through implanted leads placed near the DRG. Compared with traditional spinal cord stimulation, DRGS provides highly targeted pain relief with fewer unwanted sensations.
Over the past decade, DRGS has become an established treatment for conditions such as complex regional pain syndrome (CRPS), causalgia, chronic low back pain, and post-surgical neuropathic pain. Modern programming favors sub-threshold settings, in which stimulation is delivered below the level that causes tingling sensations (paresthesias). Although widely adopted, the specific contribution of sub-threshold stimulation has never been confirmed in a sham-controlled trial.
This study is the first randomized, double-blind, sham-controlled trial to directly evaluate whether sub-threshold DRG stimulation provides pain relief beyond placebo. Adults with an implanted DRG stimulator who have shown sustained pain relief will be randomized in a two-period crossover design to receive either active sub-threshold stimulation or sham stimulation, each for 5 days, with a washout period in between.
The primary objective is to determine whether sub-threshold DRG stimulation reduces mean daily pain intensity compared with sham. Secondary objectives include assessing sleep quality, mood, daily activity, and safety/tolerability. Exploratory measures include device logs and rescue medication use.
The findings of this trial will provide critical evidence on the efficacy of sub-threshold DRG stimulation, helping to inform clinical guidelines, payer decisions, and neuromodulation programming strategies worldwide.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
- Model description
- Randomised, double blinded, sham study
| Arm | Type | Receives |
|---|---|---|
| Subtreshhold DRG-S | Active comparator | Device: Subtreshhold DRG-SActive Sub-threshold DRG Stimulation Participants receive sub-threshold dorsal root ganglion (DRG) stimulation. Device amplitude is individually titrated to 80% of the perception threshold, ensuring no paresthesia is felt. Frequency and pulse width remain unchanged from each participant's established clinical settings. Stimulation is delivered continuously for 5 days. |
| Sham | Sham comparator | Other: ShamSham Stimulation Participants receive sham stimulation. The implanted DRG stimulator is switched off, with device interrogation logs masked to maintain blinding. The sham condition lasts for 5 days. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Adults, age 18 years or older
- Implanted with a dorsal root ganglion (DRG) stimulator for chronic neuropathic pain
- Have experienced at least 50% reduction in pain for 3 months or longer on standard DRG therapy
- Stable pain medication regimen for at least 4 weeks before enrollment
- Able and willing to complete electronic diaries and attend study visits
Key exclusion criteria (5 listed)
- Active infection or wound complication at the stimulator implant site
- Significant psychiatric illness (for example, uncontrolled depression or psychosis)
- Planned surgery, device reprogramming, or medication changes during the study period
- Currently pregnant or breastfeeding
- Occurrence of any adverse event that meets predefined withdrawal criteria during the study (such as intolerable pain or device-related complications)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Subtreshhold DRG-SContinuous electrical stimulation delivered through an implanted DRG neurostimulator. Amplitude is set individually to 80% of each participant's perception threshold, ensuring no paresthesia is produced. Frequency and pulse width remain unchanged from the participant's established therapeutic settings. This sub-threshold programming distinguishes the intervention from suprathreshold (paresthesia-based) DRG stimulation used in earlier studies. | Device | Subtreshhold DRG-S |
| ShamThe implanted DRG stimulator remains switched off for the entire 5-day period. Device interrogation logs are masked to maintain blinding. No electrical stimulation is delivered, allowing a placebo-controlled comparison with active sub-threshold stimulation. | Other | Sham |
Primary outcome
Average daily pain intensity (Numeric Rating Scale, 0-10)
Time frame: Twice daily (morning and evening) from Day 0 through Day 11 (includes both 5-day treatment periods and the two 24-hour washout periods on Day 0 and Day 6).
Self-reported pain intensity recorded twice daily (morning and evening) using an 11-point Numeric Rating Scale (0 = no pain, 10 = worst pain imaginable). Daily scores will be averaged across each treatment and washout period.
4 secondary outcomes
Sleep quality (Patient Global Impression of Change, PGIC)
Time frame: Daily in the morning from Day 0 through Day 11.
Mood (Patient Global Impression of Change, PGIC)
Time frame: Daily in the evening from Day 0 through Day 11.
Daily activity (Patient Global Impression of Change, PGIC)
Time frame: Daily in the evening from Day 0 through Day 11.
Adverse events
Time frame: From day 0 through end of study (day 11).
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 5 Dec 2025.
- Background: PubMed 31730273Huygen FJPM, Kallewaard JW, Nijhuis H, Liem L, Vesper J, Fahey ME, Blomme B, Morgalla MH, Deer TR, Capobianco RA. Effectiveness and Safety of Dorsal Root Ganglion Stimulation for the Treatment of Chronic Pain: A Pooled Analysis. Neuromodulation. 2020 Feb;23(2):213-221. doi: 10.1111/ner.13074. Epub 2019 Nov 15.
- Background: PubMed 35994195D'Souza RS, Kubrova E, Her YF, Barman RA, Smith BJ, Alvarez GM, West TE, Abd-Elsayed A. Dorsal Root Ganglion Stimulation for Lower Extremity Neuropathic Pain Syndromes: An Evidence-Based Literature Review. Adv Ther. 2022 Oct;39(10):4440-4473. doi: 10.1007/s12325-022-02244-9. Epub 2022 Aug 22.
- Background: PubMed 28030470Deer TR, Levy RM, Kramer J, Poree L, Amirdelfan K, Grigsby E, Staats P, Burton AW, Burgher AH, Obray J, Scowcroft J, Golovac S, Kapural L, Paicius R, Kim C, Pope J, Yearwood T, Samuel S, McRoberts WP, Cassim H, Netherton M, Miller N, Schaufele M, Tavel E, Davis T, Davis K, Johnson L, Mekhail N. Dorsal root ganglion stimulation yielded higher treatment success rate for complex regional pain syndrome and causalgia at 3 and 12 months: a randomized comparative trial. Pain. 2017 Apr;158(4):669-681. doi: 10.1097/j.pain.0000000000000814.
- Background: PubMed 36942306Chapman KB, Sayed D, Lamer T, Hunter C, Weisbein J, Patel KV, Dickerson D, Hagedorn JM, Lee DW, Amirdelfan K, Deer T, Chakravarthy K. Best Practices for Dorsal Root Ganglion Stimulation for Chronic Pain: Guidelines from the American Society of Pain and Neuroscience. J Pain Res. 2023 Mar 14;16:839-879. doi: 10.2147/JPR.S364370. eCollection 2023.
- Background: PubMed 36705762Piedade GS, Gillner S, McPhillips PS, Vesper J, Slotty PJ. Effect of low-frequency dorsal root ganglion stimulation in the treatment of chronic pain. Acta Neurochir (Wien). 2023 Apr;165(4):947-952. doi: 10.1007/s00701-023-05500-1. Epub 2023 Jan 27.
- Derived from this study: PubMed 42128597Tabatabaei P, Wanman J, Awad A, Eriksson M, Salomonsson J, Bredemo L, Sjoberg R, Hariz MI, Blomstedt P. Subperception dorsal root ganglion stimulation versus sham stimulation in established responders: a randomized, double-blind crossover clinical trial. Reg Anesth Pain Med. 2026 May 13:rapm-2026-107906. doi: 10.1136/rapm-2026-107906. Online ahead of print.
- Individual participant dataSharing planned: Yes. De-identified individual participant data (IPD) underlying the published results will be made available. This will include outcome data reported in the manuscript. Data will be available beginning 12 months after publication, with no end date. Access will be granted to qualified researchers upon reasonable request, subject to approval of a proposal and completion of a data use agreement. Data and statistical code will also be deposited in an open repository (OSF)
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Pedram Tabatabaei Tabatabaei, M.D, Ph.D principal investigator
Univeristy hospital of northern sweden
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Subtreshhold DRG-S in people with Neuropathic Pain and Complex Regional Pain Syndromes (CRPS), run by Umeå University at 1 site in Sweden.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 5 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Sweden. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Average daily pain intensity (Numeric Rating Scale, 0-10) (time frame: Twice daily (morning and evening) from Day 0 through Day 11 (includes both 5-day treatment periods and the two 24-hour washout periods on Day 0 and Day 6).). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07170722, which also lists 6 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 Dec 2025.