Acute PainPhase 2/3NCT04251819
Buprenorphine Plus Baclofen to Increase Analgesia in Healthy Volunteers
A Phase 2/3 study testing Baclofen 5 mg and Baclofen 10mg in people with Acute Pain and Analgesia, run by University of Alabama at Birmingham at 1 site in United States.
Trial summary
To determine if baclofen will enhance buprenorphine analgesia for acute pain in healthy volunteers. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Acute Pain, Analgesia
- What is being tested?
- Baclofen 5 mg and Baclofen 10mg
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 19 participants
- Where
- 1 siteUnited States
- Study dates
- 21 Jan 2021to 15 Jun 2024
- Phase
- Phase 2/3
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
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
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- 18 years or older
- general good health
- English speaking
Who cannot join
- Pregnant or nursing
- Opioid use disorder or any substance use disorder other than nicotine
- Prescribed agonist treatment for opioid dependence or prescribed opioids for a medical condition
- Prescribed naltrexone
- Known sensitivity to buprenorphine, naloxone, or baclofen
- Acute or chronic pain condition
Show all 11Show fewer
- Trouble breathing or a pulmonary condition
- Prescribed benzodiazepines or daily use of benzodiazepines
- Positive drug screen (positive cannabis result allowed)
- Cognitive impairment or psychiatric disorder requiring treatment
- Uncontrolled hypertension
Trial locations and contacts
1 site in 1 country.
United States1 site
University of Alabama, Birmingham
Birmingham, Alabama, 35209
About this study
To determine if baclofen will enhance buprenorphine analgesia for acute pain in healthy volunteers.
Read the detailed description
Abuse of opioids is a significant and growing problem in the United States. In the past two decades, opioid prescriptions have quadrupled while the age of heroin initiation has decreased, suggesting that more individuals are using opioids and transitioning to heroin and potent synthetic opioids than in the past. Further, fatal opioid overdose is now the leading cause of accidental death and is the 5th highest overall cause of mortality in the US. Engaging opioid users in opioid agonist treatments has been shown to lower rates of criminal behavior, lower rates of non-opioid drug use, and increase retention in drug treatment programs, while decreasing mortality and new HIV and hepatitis infections. However, a recent study noted that 68% of patients prescribed buprenorphine had poor medication adherence, which was associated with illicit opioid use. A Cochrane review concluded that buprenorphine was less effective at retaining patients in treatment relative to methadone. One reason for lower treatment retention may be the high comorbidity of opioid use disorder and chronic pain and/or opioid-induced hyperalgesia. Buprenorphine, as a partial mu agonist, provides lower analgesia but an improved safety profile relative to full agonists like methadone. Thus, enhancing the analgesic properties of buprenorphine will provide a safer alternative for opioid use disorder patients with chronic pain/hyperalgesia.
- Conditions
- Acute Pain, Analgesia
- Being tested
- Placebos, Baclofen 5 mg, Baclofen 10mg
- Medical subject headings
- Acute Pain, Agnosia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
PlacebosDrug
Participants will receive placebo in combination with 0.3 mg of buprenorphine to examine analgesia in acute pain tasks.
Baclofen 5 mgDrug
Participants will receive 5mg of baclofen in combination with 0.3 mg of buprenorphine to examine analgesia in acute pain tasks.
Baclofen 10mgDrug
Participants will receive 10mg of baclofen in combination with 0.3 mg of buprenorphine to examine analgesia in acute pain tasks.
| Study group | Role | What they receive |
|---|---|---|
| Placebo | Placebo comparator | Participants randomized to this arm will receive one dosage of Placebo as part of their second study appointment. Receives: Drug: Placebos |
| Baclofen 5mg | Experimental | Participants randomized to this arm will receive one dosage of 5 mg of Baclofen as part of their second study appointment. Receives: Drug: Baclofen 5 mg |
| Baclofen 10mg | Experimental | Participants randomized to this arm will receive one dosage of 10 mg of Baclofen as part of their second study appointment. Receives: Drug: Baclofen 10mg |
What is being measured
The primary outcome is the main question the study is designed to answer.
Pain Threshold
Pain threshold refers to the intensity at which a stimulus is first perceived as painful. Heat stimuli will be delivered using a computer-controlled thermal stimulation system with a 30 millimeter X 30 millimeter probe. From a baseline of 32 degrees Celsius, the probe temperature will increase at a rate of .5 degrees Celsius/second until the participant responds by pressing a button on a handheld device. For heat pain threshold, participants will be instructed to press the button when the sensation "first becomes painful" Pain rating scores will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain.
Measured: Baseline
Pain Threshold
Pain threshold refers to the intensity at which a stimulus is first perceived as painful. Heat stimuli will be delivered using a computer-controlled thermal stimulation system with a 30 millimeter X 30 millimeter probe. From a baseline of 32 degrees Celsius, the probe temperature will increase at a rate of .5 degrees Celsius/second until the participant responds by pressing a button on a handheld device. For heat pain threshold, participants will be instructed to press the button when the sensation "first becomes painful" Pain rating scores will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain.
Measured: 1.5 hours post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
Pain Tolerance
Pain tolerance refers to the maximum amount of pain produced by a stimulus that a person is able/willing to tolerate. Heat stimuli will again be delivered using the computer-controlled thermal stimulation system. From a baseline of 32 degrees Celsius, the probe temperature will increase at a rate of .5 degrees Celsius/second until the participant responds by pressing a button on a handheld device. For heat pain tolerance, participants will be instructed to press the button when they are "no longer willing to tolerate" the painful sensation. Pain rating scores will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain.
Measured: Baseline
Pain Tolerance
Pain tolerance refers to the maximum amount of pain produced by a stimulus that a person is able/willing to tolerate. Heat stimuli will again be delivered using the computer-controlled thermal stimulation system. From a baseline of 32 degrees Celsius, the probe temperature will increase at a rate of .5 degrees Celsius/second until the participant responds by pressing a button on a handheld device. For heat pain tolerance, participants will be instructed to press the button when they are "no longer willing to tolerate" the painful sensation. Pain rating scores will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain.
Measured: 1.5 hours post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
Temporal Summation of Pain
Temporal summation of pain refers to a form of endogenous pain facilitation characterized by the perception of increased pain despite constant or even reduced peripheral afferent input. Temporal summation is presumed to be the psychophysical manifestation of wind-up. Wind-up is a phenomenon where repetitive stimulation of C primary afferents at rates greater than 0.3 Hertz produces a slowly increasing response of second-order neurons in the spinal cord. Pain rating scores will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain.
Measured: Baseline
Temporal Summation of Pain
Temporal summation of pain refers to a form of endogenous pain facilitation characterized by the perception of increased pain despite constant or even reduced peripheral afferent input. Temporal summation is presumed to be the psychophysical manifestation of wind-up. Wind-up is a phenomenon where repetitive stimulation of C primary afferents at rates greater than 0.3 Hertz produces a slowly increasing response of second-order neurons in the spinal cord. Pain rating scores will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain.
Measured: 1.5 hours post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
Conditioned Pain Modulation
A routinely used quantitative sensory testing protocol for the measurement of endogenous pain inhibition is conditioned pain modulation, which refers to the reduction in pain from one stimulus (the test stimulus) produced by the application of a second pain stimulus at a remote body site (the conditioning stimulus). Conditioned pain modulation is believed to reflect the perceptual manifestation of diffuse noxious inhibitory controls, whereby ascending projections from one noxious stimulus activate supraspinal structures that trigger descending inhibitory projections to the dorsal horn. Pain rating scores for the test stimulus and the conditioning stimulus will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain. The conditioned pain modulation score is the difference between the two pain rating scores.
Measured: Baseline
Conditioned Pain Modulation
A routinely used quantitative sensory testing protocol for the measurement of endogenous pain inhibition is conditioned pain modulation, which refers to the reduction in pain from one stimulus (the test stimulus) produced by the application of a second pain stimulus at a remote body site (the conditioning stimulus). Conditioned pain modulation is believed to reflect the perceptual manifestation of diffuse noxious inhibitory controls, whereby ascending projections from one noxious stimulus activate supraspinal structures that trigger descending inhibitory projections to the dorsal horn. Pain rating scores for the test stimulus and the conditioning stimulus will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain. The conditioned pain modulation score is the difference between the two pain rating scores.
Measured: 1.5 hours post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
Suprathreshold Pain Response
Ratings of pain in response to discrete stimuli with intensities above the pain threshold detection/ patients provide an intensity rating using any number of a 0-100 scale whereby 0=no pain and 100= the most intense pain imaginable
Measured: Baseline
Suprathreshold Pain Response
Ratings of pain in response to discrete stimuli with intensities above the pain threshold detection/ patients provide an intensity rating using any number of a 0-100 scale whereby 0=no pain and 100= the most intense pain imaginable
Measured: 1.5 hours post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
Secondary outcomes (4)
Opioid Symptom Checklist
Measures the amount and intensity of side effects after being administered an opioid. The measure consists of 14 questions about potential opioid symptoms, and each the severity of the symptom is rated on a scale from 0 to 4, with 0 reflecting not at all feeling or being bothered by the symptom and 4 reflecting being severely bothered by the symptom. The score is the sum of the 14 responses. The minimum value is 0 and the maximum value is 56.
Measured: 30 minutes post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
26-item Visual Analog Scale (VAS)
Measures subjective and physiological effects of a medication using mood states as well as questions about the dose of medication. The measure consists of 7 questions about potential drug effects, and each response is rated on a scale of 0 to 100, with 0 reflecting not at all feeling the effect and 100 reflecting very much feeling the effect. The score is the sum of the 7 responses. The minimum value is 0 and the maximum value is 700.
Measured: 30 minutes post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
Drug Effects Questionnaire-5
Measures subjective experiences of a drug. The measure consists of 5 questions about the participant's experience of the drug effects, and each response is rated on a scale of 0 to 100, with 0 reflecting not at all having an experience and 100 reflecting extremely having that experience. The score is the sum of the 5 responses. The minimum value is 0 and the maximum value is 500.
Measured: 30 minutes post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
26-item Visual Analog Scale ("Subjective Drug Effects")
This 26-item VAS measures subjective and physiological effects of a medication using mood states as well as questions about the dose of medication. The measure consists of 7 questions about potential drug effects, and each response is rated on a scale of 0 to 100, with 0 reflecting not at all feeling the effect and 100 reflecting very much feeling the effect. The score is the sum of the 7 responses. The minimum value is 0 and the maximum value is 700.
Measured: 30 minutes post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 Feb 2020
- Study start21 Jan 2021
- Primary completion15 Jun 2024
- Study completion15 Jun 2024
Why it stopped: No funding for this project
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for Acute PainStudies of the same condition, open and under way.
- More trials run by University of Alabama at BirminghamThe sponsor's other registered studies.
- 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 2/3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Participants will be randomized to one of three interventions.
- Masking
- None (open label)
- Enrolment
- 19 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Alabama at Birmingham
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Karen Cropsey, University of Alabama at Birmingham
- Investigators
- Karen L Cropsey, Psy.D., Principal investigator, University of Alabama at Birmingham
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04251819
- Sponsor's protocol ID
- 300004505
- Status last verified
- Oct 2025
- First submitted
- 18 Dec 2019
- Last updated
- 7 Jan 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 7 Jan 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Buprenorphine Plus Baclofen to Increase Analgesia in Healthy Volunteers
- ClinicalTrials.gov ID
- NCT04251819
- Acronym / sponsor ID
- 300004505
- Conditions
- Acute Pain, Analgesia
- Phase
- Phase 2/3
- Study type
- Interventional
- Recruitment status
- TerminatedReason stopped: No funding for this project
- Enrolment
- 19 participants (actual)
- Lead sponsor
- University of Alabama at BirminghamUniversity, hospital or other
- Study start
- 21 Jan 2021 (actual)
- Primary completion
- 15 Jun 2024 (actual)
- Study completion
- 15 Jun 2024 (actual)
- First posted
- 5 Feb 2020 (actual)
- Results
- Posted 7 Jan 2026
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
To determine if baclofen will enhance buprenorphine analgesia for acute pain in healthy volunteers.
Detailed description
Abuse of opioids is a significant and growing problem in the United States. In the past two decades, opioid prescriptions have quadrupled while the age of heroin initiation has decreased, suggesting that more individuals are using opioids and transitioning to heroin and potent synthetic opioids than in the past. Further, fatal opioid overdose is now the leading cause of accidental death and is the 5th highest overall cause of mortality in the US. Engaging opioid users in opioid agonist treatments has been shown to lower rates of criminal behavior, lower rates of non-opioid drug use, and increase retention in drug treatment programs, while decreasing mortality and new HIV and hepatitis infections. However, a recent study noted that 68% of patients prescribed buprenorphine had poor medication adherence, which was associated with illicit opioid use. A Cochrane review concluded that buprenorphine was less effective at retaining patients in treatment relative to methadone. One reason for lower treatment retention may be the high comorbidity of opioid use disorder and chronic pain and/or opioid-induced hyperalgesia. Buprenorphine, as a partial mu agonist, provides lower analgesia but an improved safety profile relative to full agonists like methadone. Thus, enhancing the analgesic properties of buprenorphine will provide a safer alternative for opioid use disorder patients with chronic pain/hyperalgesia.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 3
- Model description
- Participants will be randomized to one of three interventions.
| Arm | Type | Receives |
|---|---|---|
| Placebo | Placebo comparator | Drug: PlacebosParticipants randomized to this arm will receive one dosage of Placebo as part of their second study appointment. |
| Baclofen 5mg | Experimental | Drug: Baclofen 5 mgParticipants randomized to this arm will receive one dosage of 5 mg of Baclofen as part of their second study appointment. |
| Baclofen 10mg | Experimental | Drug: Baclofen 10mgParticipants randomized to this arm will receive one dosage of 10 mg of Baclofen as part of their second study appointment. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- 18 years or older
- general good health
- English speaking
Key exclusion criteria (11 listed)
- Pregnant or nursing
- Opioid use disorder or any substance use disorder other than nicotine
- Prescribed agonist treatment for opioid dependence or prescribed opioids for a medical condition
- Prescribed naltrexone
- Known sensitivity to buprenorphine, naloxone, or baclofen
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 |
|---|---|---|
| PlacebosParticipants will receive placebo in combination with 0.3 mg of buprenorphine to examine analgesia in acute pain tasks. | Drug | Placebo |
| Baclofen 5 mgParticipants will receive 5mg of baclofen in combination with 0.3 mg of buprenorphine to examine analgesia in acute pain tasks. | Drug | Baclofen 5mg |
| Baclofen 10mgParticipants will receive 10mg of baclofen in combination with 0.3 mg of buprenorphine to examine analgesia in acute pain tasks. | Drug | Baclofen 10mg |
Primary outcome
Pain Threshold
Time frame: Baseline
Pain threshold refers to the intensity at which a stimulus is first perceived as painful. Heat stimuli will be delivered using a computer-controlled thermal stimulation system with a 30 millimeter X 30 millimeter probe. From a baseline of 32 degrees Celsius, the probe temperature will increase at a rate of .5 degrees Celsius/second until the participant responds by pressing a button on a handheld device. For heat pain threshold, participants will be instructed to press the button when the sensation "first becomes painful" Pain rating scores will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain.
Pain Threshold
Time frame: 1.5 hours post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
Pain threshold refers to the intensity at which a stimulus is first perceived as painful. Heat stimuli will be delivered using a computer-controlled thermal stimulation system with a 30 millimeter X 30 millimeter probe. From a baseline of 32 degrees Celsius, the probe temperature will increase at a rate of .5 degrees Celsius/second until the participant responds by pressing a button on a handheld device. For heat pain threshold, participants will be instructed to press the button when the sensation "first becomes painful" Pain rating scores will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain.
Pain Tolerance
Time frame: Baseline
Pain tolerance refers to the maximum amount of pain produced by a stimulus that a person is able/willing to tolerate. Heat stimuli will again be delivered using the computer-controlled thermal stimulation system. From a baseline of 32 degrees Celsius, the probe temperature will increase at a rate of .5 degrees Celsius/second until the participant responds by pressing a button on a handheld device. For heat pain tolerance, participants will be instructed to press the button when they are "no longer willing to tolerate" the painful sensation. Pain rating scores will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain.
Pain Tolerance
Time frame: 1.5 hours post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
Pain tolerance refers to the maximum amount of pain produced by a stimulus that a person is able/willing to tolerate. Heat stimuli will again be delivered using the computer-controlled thermal stimulation system. From a baseline of 32 degrees Celsius, the probe temperature will increase at a rate of .5 degrees Celsius/second until the participant responds by pressing a button on a handheld device. For heat pain tolerance, participants will be instructed to press the button when they are "no longer willing to tolerate" the painful sensation. Pain rating scores will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain.
Temporal Summation of Pain
Time frame: Baseline
Temporal summation of pain refers to a form of endogenous pain facilitation characterized by the perception of increased pain despite constant or even reduced peripheral afferent input. Temporal summation is presumed to be the psychophysical manifestation of wind-up. Wind-up is a phenomenon where repetitive stimulation of C primary afferents at rates greater than 0.3 Hertz produces a slowly increasing response of second-order neurons in the spinal cord. Pain rating scores will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain.
Temporal Summation of Pain
Time frame: 1.5 hours post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
Temporal summation of pain refers to a form of endogenous pain facilitation characterized by the perception of increased pain despite constant or even reduced peripheral afferent input. Temporal summation is presumed to be the psychophysical manifestation of wind-up. Wind-up is a phenomenon where repetitive stimulation of C primary afferents at rates greater than 0.3 Hertz produces a slowly increasing response of second-order neurons in the spinal cord. Pain rating scores will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain.
Conditioned Pain Modulation
Time frame: Baseline
A routinely used quantitative sensory testing protocol for the measurement of endogenous pain inhibition is conditioned pain modulation, which refers to the reduction in pain from one stimulus (the test stimulus) produced by the application of a second pain stimulus at a remote body site (the conditioning stimulus). Conditioned pain modulation is believed to reflect the perceptual manifestation of diffuse noxious inhibitory controls, whereby ascending projections from one noxious stimulus activate supraspinal structures that trigger descending inhibitory projections to the dorsal horn. Pain rating scores for the test stimulus and the conditioning stimulus will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain. The conditioned pain modulation score is the difference between the two pain rating scores.
Conditioned Pain Modulation
Time frame: 1.5 hours post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
A routinely used quantitative sensory testing protocol for the measurement of endogenous pain inhibition is conditioned pain modulation, which refers to the reduction in pain from one stimulus (the test stimulus) produced by the application of a second pain stimulus at a remote body site (the conditioning stimulus). Conditioned pain modulation is believed to reflect the perceptual manifestation of diffuse noxious inhibitory controls, whereby ascending projections from one noxious stimulus activate supraspinal structures that trigger descending inhibitory projections to the dorsal horn. Pain rating scores for the test stimulus and the conditioning stimulus will be reflected in scores of 0-100, 0 being the least amount of pain and 100 being the most amount of pain. The conditioned pain modulation score is the difference between the two pain rating scores.
Suprathreshold Pain Response
Time frame: Baseline
Ratings of pain in response to discrete stimuli with intensities above the pain threshold detection/ patients provide an intensity rating using any number of a 0-100 scale whereby 0=no pain and 100= the most intense pain imaginable
Suprathreshold Pain Response
Time frame: 1.5 hours post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
Ratings of pain in response to discrete stimuli with intensities above the pain threshold detection/ patients provide an intensity rating using any number of a 0-100 scale whereby 0=no pain and 100= the most intense pain imaginable
4 secondary outcomes
Opioid Symptom Checklist
Time frame: 30 minutes post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
26-item Visual Analog Scale (VAS)
Time frame: 30 minutes post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
Drug Effects Questionnaire-5
Time frame: 30 minutes post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
26-item Visual Analog Scale ("Subjective Drug Effects")
Time frame: 30 minutes post-drug administration during session 2, occurs 7 ± 2 days after baseline visit
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 7 Jan 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
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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.
Karen L Cropsey, Psy.D. principal investigator
University of Alabama at Birmingham
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2/3 study testing Baclofen 5 mg and Baclofen 10mg in people with Acute Pain and Analgesia, run by University of Alabama at Birmingham at 1 site in United States.
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 3 inclusion and 11 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: stopped early, as of the sponsor's last update on 7 Jan 2026. 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 United States. 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.
What does this combined phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 7 Jan 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
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?
Pain Threshold (time frame: Baseline). The study lists 10 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 7 Jan 2026.