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Effect of Gabapentin Enacarbil on Opioid Consumption and Pain Scores

A Randomized Controlled Trial to Determine the Effect of Gabapentin Enacarbil on Opioid Consumption and Pain Scores in Patients Having Hip and Knee Arthroplasties With Spinal Anesthesia

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02840240
Enrollment
107
Registered
2016-07-21
Start date
2016-01-31
Completion date
2021-04-23
Last updated
2024-01-09

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Pain

Brief summary

Opioids are effective analgesics, but cause side effects including sedation, respiratory depression, low blood pressure, nausea, and constipation. Gabapentin enacarbil, which is a FDA approved drug for post herpetic neuralgia (nerve pain related to shingles) and restless leg syndrome, may decrease your need for narcotics and thus decrease the risk of side effects. The investigator hopes this study will determine if gabapentin enacarbil decreases opioid consumption and pain after surgery. Patients having elective hip and knee surgery will be asked to participate in the study. Patients will be randomized to Gabapentin enacarbil 600mg twice per day for 5 days or Placebo twice per day for 5 days. One day prior to surgery the patient will take Gabapentin enacarbil 600mg or placebo 600mg twice a day with meals. On the day of surgery, the patient will take Gabapentin enacarbil 600mg or placebo 600mg two hours before the surgical procedure. Six hours after the completion of surgery, the patient will receive Gabapentin enacarbil 600mg or placebo 600mg. If the patient is sent home, the patient will be given 6 Gabapentin enacarbil 600mg or placebo 600mg pills to take home along with instructions. However, if the patient remains hospitalized, on the first day after the surgery, the patient will have pain assessed in the morning using a numerical rating score. The patient's quality of recovery will be evaluated using a questionnaire and the patient will receive Gabapentin enacarbil 600mg or placebo 600mg twice a day with meals. The second and third day the patient is in the hospital, the patient will have pain assessed in the morning using a numerical rating score and the patient will receive Gabapentin enacarbil 600mg or placebo 600mg twice a day with meals. Then, three months after surgery, the patient will receive a phone call to follow-up with possible pain or discomfort the patient may be feeling.

Detailed description

A randomized controlled trial to determine the effect of gabapentin enacarbil on opioid consumption and pain scores in patients having primary hip or knee replacement surgery with spinal anesthesia. Screening visit * Consent will be obtained * Vital Signs * Physical evaluation * Medical History * Laboratory values and medication checked via Epic * Pain scores using numerical rating scores (NRS) * Brief pain inventory (BPI) * Randomization will be to standard management with GEn or to standard management with placebo. Patients will be given GEn 600 mg bid or placebo 600 mg bid for 1 preoperative day and will receive 600 mg GEn or placebo about 2 hours before surgery and then restarted on GEn or placebo 600 mg within 6 hours of surgery, and then 600 mg bid for three additional days. 2 days prior to surgery Phone call will be made to remind patients to take GEn 600 mg bid or placebo 600 mg bid 1 day prior to surgery * vital signs * GEn 600 mg bid or placebo 600 mg bid * monitoring and recording of adverse events Day of Surgery * Medical History * Laboratory values and medication checked via Epic * Patients will be given GEn 600 mg or placebo single dose with sips of water 2 hours before surgery and then restarted within 6 hours of completion of surgery. * Vital Signs * Social history * Demographic data to be obtained includes height (cm), weight (kg), age (yr), gender, (ASA) physical status, and self-declared ethnicity * Individual risk for nausea and vomiting will be determined using the Apfel score. * Monitoring and recording of adverse events * Pain scores using numerical rating scores (NRS) during the PACU stay every 15 minutes for the first hour after surgery POD 1 * GEn 600 mg bid or placebo 600 mg bid * Vital Signs * Monitoring and Recording of adverse events * Pain scores using numerical rating scores (NRS) in the morning * Myles QoR scale to formally evaluate quality of recovery POD 2 * GEn 600 mg bid or placebo 600 mg bid * Vital Signs * Monitoring and Recording of adverse events * Pain scores using numerical rating scores (NRS) in the morning POD 3 * GEn 600 mg bid or placebo 600 mg bid * Vital Signs * Monitoring and Recording of adverse events * Pain scores using numerical rating scores (NRS) in the morning 3 Months after surgery * Phone call will be made to check for any adverse event and with the intention to assess chronic pain. * Monitoring and recording of adverse events * Data obtained from electronic medical records will include: operation time, surgery type, intraoperative opioid consumption, postoperative opioid consumption in PACU and in ward, breakthrough pain medication requirements, pain scores in PACU and ward, requirement of antiemetics for nausea and vomiting, requirement of antihistaminic medications, requirement of laxatives for constipation, ambulation time, flatus, ileus, bowel movements, length of stay and any side effects or complications. Preoperative and postoperative laboratory data including but not limited to renal function will also be collected from electronic medical records. Patient functionality will also be recorded including, bathing, toileting, walking and moving.

Interventions

600 mg BID 1 day pre-op and 2 hours before surgery, 6 hours after surgery, 600 mg BID 3 days post-operative

DRUGPlacebo

600 mg BID taken 1 day pre-op and 2 hours before surgery, 6 hours after surgery, 600 mg 3 days post-operative

Sponsors

The Cleveland Clinic
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No

Inclusion criteria

1. Men or women 18-85 years of age. 2. Scheduled for elective knee or hip arthroplasty with spinal anesthesia.

Exclusion criteria

1. Creatinine \>1.50 mg/dl. 2. History of clinically important current depression or currently on any prescribed anti-depressant medication. 3. Previously enrolled in any Xenoport trial. 4. Use of gabapentin or gabapentinoids (Lyrica, Horizant, Neurontin or Gralise) within one month. 5. Allergy to gabapentin or gabapentinoids (Lyrica, Horizant, Neurontin or Gralise). 6. Women who are pregnant or breastfeeding. 7. History of seizure disorder within the last one-year or taking medications for seizures.

Design outcomes

Primary

MeasureTime frameDescription
Time Weighted Average Pain Score in Numerical Rating ScoresInitial 72 hours after surgery or until discharge, whatever comes first.Multiple pain measurements (numeric rating scale ranges from 0 to 10, where 0 - no pain and 10 - worse imaginable pain) over 72 hours after the surgery will be summarized by computing time weighted average pain score for each patient
Cumulative Postoperative Opioid ConsumptionInitial 72 hours after surgery or until discharge, whatever comes first.The total dose of opioid administered in the PACU and floor including the background analgesia (PCA) and boluses. All opioids will be converted into mg intravenous (IV) morphine equivalent to standardize opioid consumption .

Secondary

MeasureTime frameDescription
Number of Participants With Persistent Pain 90-day After Surgerywithin 90 days after surgeryNumber of participants with persistent pain at 90 days after surgery
Postoperative Nausea and Vomiting (PONV) up to 72 Hours After SurgeryInitial 72 hours after surgeryPostoperative nausea and vomiting (PONV) were recorded daily by nurses.
Length of Hospital Stay in HoursFrom the end of surgery to dischargeDuration of hospitalization (hours) was recorded from the end of surgery to discharge, and compared between groups on the medians.
Quality of Recovery (QoR-15) Score 72 Hours After SurgeryInitial 72 hours after surgery or shortly before hospital discharge.Quality of Recovery (QoR-15) survey was assessed by blinded investigators at 72 hours after surgery or shortly before hospital discharge, whichever came first. It is a patient-reported outcome ranging from 0 to 150. The higher scale indicates better recovery.

Countries

United States

Participant flow

Participants by arm

ArmCount
Gabapentin Enacarbil
Patients going through elective hip or knee replacement surgery with spinal anesthesia will receive Gabapentin enacarbil for 5 days Gabapentin enacarbil: 600 mg BID 1 day pre-op and 2 hours before surgery, 6 hours after surgery, 600 mg BID 3 days post-operative
28
Placebo
Patients going through elective hip or knee replacement surgery with spinal anesthesia will receive placebo for 5 days Placebo: 600 mg BID taken 1 day pre-op and 2 hours before surgery, 6 hours after surgery, 600 mg 3 days post-operative
32
Total60

Baseline characteristics

CharacteristicGabapentin EnacarbilTotalPlacebo
Age, Continuous65 years
STANDARD_DEVIATION 11
66 years
STANDARD_DEVIATION 10
66 years
STANDARD_DEVIATION 9
Height169 cm
STANDARD_DEVIATION 11
169 cm
STANDARD_DEVIATION 10
169 cm
STANDARD_DEVIATION 10
Race/Ethnicity, Customized
African American
2 Participants4 Participants2 Participants
Race/Ethnicity, Customized
Caucasian/white
25 Participants54 Participants29 Participants
Race/Ethnicity, Customized
Other
1 Participants2 Participants1 Participants
Sex: Female, Male
Female
17 Participants34 Participants17 Participants
Sex: Female, Male
Male
11 Participants26 Participants15 Participants
Weight90 kg
STANDARD_DEVIATION 26
90 kg
STANDARD_DEVIATION 23
90 kg
STANDARD_DEVIATION 20

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 280 / 32
other
Total, other adverse events
0 / 280 / 32
serious
Total, serious adverse events
0 / 280 / 32

Outcome results

Primary

Cumulative Postoperative Opioid Consumption

The total dose of opioid administered in the PACU and floor including the background analgesia (PCA) and boluses. All opioids will be converted into mg intravenous (IV) morphine equivalent to standardize opioid consumption .

Time frame: Initial 72 hours after surgery or until discharge, whatever comes first.

ArmMeasureValue (MEAN)Dispersion
Gabapentin EnacarbilCumulative Postoperative Opioid Consumption4.0 mgStandard Deviation 1.6
PlaceboCumulative Postoperative Opioid Consumption4.1 mgStandard Deviation 1.7
Comparison: Comparisons of opioid consumption were conducted independently for each study site. This analysis is for patients at the Cleveland Clinic main campus.p-value: 0.7795% CI: [0.21, 18.54]Regression, Linear
Comparison: Comparisons of opioid consumption were conducted independently for each study site. This analysis is for patients at the Cleveland Clinic Fairview hospital.p-value: 0.0995% CI: [0.03, 3.16]Regression, Linear
Primary

Time Weighted Average Pain Score in Numerical Rating Scores

Multiple pain measurements (numeric rating scale ranges from 0 to 10, where 0 - no pain and 10 - worse imaginable pain) over 72 hours after the surgery will be summarized by computing time weighted average pain score for each patient

Time frame: Initial 72 hours after surgery or until discharge, whatever comes first.

ArmMeasureValue (MEAN)Dispersion
Gabapentin EnacarbilTime Weighted Average Pain Score in Numerical Rating Scores4.0 score on a scaleStandard Deviation 1.6
PlaceboTime Weighted Average Pain Score in Numerical Rating Scores4.1 score on a scaleStandard Deviation 1.7
p-value: 0.00395% CI: [-1.07, 0.69]Regression, Linear
Secondary

Length of Hospital Stay in Hours

Duration of hospitalization (hours) was recorded from the end of surgery to discharge, and compared between groups on the medians.

Time frame: From the end of surgery to discharge

ArmMeasureValue (MEDIAN)
Gabapentin EnacarbilLength of Hospital Stay in Hours78 hours
PlaceboLength of Hospital Stay in Hours76 hours
Secondary

Number of Participants With Persistent Pain 90-day After Surgery

Number of participants with persistent pain at 90 days after surgery

Time frame: within 90 days after surgery

Population: There were 5 participants in gabapentin enacarbil group and 4 in placebo group with missing value in this outcome.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Gabapentin EnacarbilNumber of Participants With Persistent Pain 90-day After Surgery7 Participants
PlaceboNumber of Participants With Persistent Pain 90-day After Surgery3 Participants
p-value: 0.1198.75% CI: [0.5, 24.3]Regression, Logistic
Secondary

Postoperative Nausea and Vomiting (PONV) up to 72 Hours After Surgery

Postoperative nausea and vomiting (PONV) were recorded daily by nurses.

Time frame: Initial 72 hours after surgery

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Gabapentin EnacarbilPostoperative Nausea and Vomiting (PONV) up to 72 Hours After Surgery8 Participants
PlaceboPostoperative Nausea and Vomiting (PONV) up to 72 Hours After Surgery12 Participants
p-value: 0.698.75% CI: [0.2, 3.1]Regression, Logistic
Secondary

Quality of Recovery (QoR-15) Score 72 Hours After Surgery

Quality of Recovery (QoR-15) survey was assessed by blinded investigators at 72 hours after surgery or shortly before hospital discharge, whichever came first. It is a patient-reported outcome ranging from 0 to 150. The higher scale indicates better recovery.

Time frame: Initial 72 hours after surgery or shortly before hospital discharge.

Population: There were 3 participants in gabapentin enacarbil group and 1 in placebo group with missing value in this outcome.

ArmMeasureValue (MEAN)Dispersion
Gabapentin EnacarbilQuality of Recovery (QoR-15) Score 72 Hours After Surgery114 score on a scaleStandard Deviation 19
PlaceboQuality of Recovery (QoR-15) Score 72 Hours After Surgery118 score on a scaleStandard Deviation 15

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026