Trial Outcomes & Findings for Study Evaluating the Abuse Potential of NEURONTIN® in Healthy Non-drug Dependent, Recreational Opioid Users (NCT NCT05319756)

NCT ID: NCT05319756

Last Updated: 2023-08-14

Results Overview

Drug liking assesses how much a participant likes or dislikes a drug effect at the time the question ("at this moment, my liking this drug is") is being asked. It is scored using a 100 mm visual analogue scale (VAS), where 0 mm = "Strong Disliking", 50 mm = "Neither Like nor Dislike", and 100 mm = "Strong Liking"

• Recruitment status: COMPLETED
• Study phase: PHASE4
• Target enrollment: 54 participants
• Primary outcome timeframe: up to 48 hours after treatments
• Results posted on: 2023-08-14

Participant Flow

Subjects were entered into a Qualification phase involving a naloxone challenge test (to exclude subjects who were opioid dependent) and a drug discrimination test (to confirm they can tell the difference between oxycodone and placebo). Only subjects who passed the tests in the Qualification phase were randomized into the Treatment phase where they received the 6 different single dose study treatments, each separated by a washout of at least 4 days, in the order specified for Sequences 1-6 below

Participant milestones

Measure	Sequence 1 Period 1: Oxycodone 20 mg; Period 2: Placebo; Period 3: Gabapentin 1200 mg plus Oxycodone 20 mg; Period 4: Gabapentin 600 mg; Period 5: Gabapentin 600 mg plus Oxycodone 20 mg; Period 6: Gabapentin 1200 mg	Sequence 2 Period 1: Placebo; Period 2: Gabapentin 600 mg; Period 3: Oxycodone 20 mg; Period 4: Gabapentin 1200 mg; Period 5: Gabapentin 1200 mg plus Oxycodone 20 mg; Period 6: Gabapentin 600 mg plus Oxycodone 20 mg	Sequence 3 Period 1: Gabapentin 600 mg; Period 2: Gabapentin 1200 mg; Period 3: Placebo; Period 4 Gabapentin 600 mg plus Oxycodone 20 mg; Period 5: Oxycodone 20 mg; Period 6: Gabapentin 1200 mg plus Oxycodone 20 mg	Sequence 4 Period 1: Gabapentin 1200 mg; Period 2: Gabapentin 600 mg plus Oxycodone 20 mg; Period 3: Gabapentin 600 mg; Period 4: Gabapentin 1200 mg plus Oxycodone 20 mg; Period 5: Placebo; Period 6: Oxycodone 20 mg	Sequence 5 Period 1: Gabapentin 600 mg plus Oxycodone 20 mg; Period 2: Gabapentin 1200 mg plus Oxycodone 20 mg; Period 3: Gabapentin 1200 mg; Period 4: Oxycodone 20 mg; Period 5: Gabapentin 600 mg; Period 6: Placebo	Sequence 6 Period 1: Gabapentin 1200 mg plus Oxycodone 20 mg; Period 2: Oxycodone 20 mg; Period 3: Gabapentin 600 mg plus Oxycodone 20 mg; Period 4: Placebo; Period 5: Gabapentin 1200 mg; Period 6: Gabapentin 600 mg
Overall Study STARTED	9	9	9	9	9	9
Overall Study COMPLETED	8	8	9	9	8	8
Overall Study NOT COMPLETED	1	1	0	0	1	1

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Study Evaluating the Abuse Potential of NEURONTIN® in Healthy Non-drug Dependent, Recreational Opioid Users

Baseline characteristics by cohort

Measure	Randomized Population n=54 Participants All participants who were randomized to a treatment sequence in the Treatment Phase.
Age, Continuous	33.3 Years STANDARD_DEVIATION 8.41 • n=5 Participants
Sex: Female, Male Female	16 Participants n=5 Participants
Sex: Female, Male Male	38 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	12 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	42 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants
Race (NIH/OMB) Asian	0 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	1 Participants n=5 Participants
Race (NIH/OMB) Black or African American	35 Participants n=5 Participants
Race (NIH/OMB) White	13 Participants n=5 Participants
Race (NIH/OMB) More than one race	4 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	1 Participants n=5 Participants
Region of Enrollment United States	54 participants n=5 Participants

PRIMARY outcome

Timeframe: up to 48 hours after treatments

Population: The analysis population was the modified completer population which included subjects who completed all 6 treatment periods but excluded those identified during data review as having maximum Drug Liking scores that were similar for all 6 treatments or who had high placebo responses

Drug liking assesses how much a participant likes or dislikes a drug effect at the time the question ("at this moment, my liking this drug is") is being asked. It is scored using a 100 mm visual analogue scale (VAS), where 0 mm = "Strong Disliking", 50 mm = "Neither Like nor Dislike", and 100 mm = "Strong Liking"

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Bipolar Visual Analog Scale (VAS) for "Drug Liking" Maximum Effect (Emax).	54.89 Score on a 100 mm scale Standard Error 2.116	87.40 Score on a 100 mm scale Standard Error 3.156	57.89 Score on a 100 mm scale Standard Error 3.142	63.62 Score on a 100 mm scale Standard Error 3.334	88.43 Score on a 100 mm scale Standard Error 3.216	92.17 Score on a 100 mm scale Standard Error 2.713

SECONDARY outcome

Timeframe: up to 48 hours after treatments

Population: Modified completer population

Time after dosing when the maximum effect for Drug Liking VAS is reached

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Bipolar VAS for "Drug Liking" - Time to Maximum Effect (TEmax)	0.25 hours Interval 0.2 to 24.0	1.00 hours Interval 0.2 to 3.5	0.25 hours Interval 0.25 to 2.5	0.28 hours Interval 0.1 to 12.1	1.00 hours Interval 0.2 to 12.0	1.50 hours Interval 0.2 to 4.0

SECONDARY outcome

Timeframe: Up to 48 hours after treatments (Assessments were made at the following timepoints after each treatment: 0, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 12, 24, 36, and 48 hours)

Population: Modified completer population

Area under the effect-time profile from time 0 to the time of the last available data for the "Drug liking" visual analog scale which assesses how much a participant likes or dislikes a drug effect at the time the question ("at this moment, my liking this drug is") is being asked. It is scored using a 100 mm visual analogue scale (VAS), where 0 mm = "Strong Disliking", 50 mm = "Neither Like nor Dislike", and 100 mm = "Strong Liking"

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Bipolar VAS for "Drug Liking": Area Under the Effect Curve From Time 0 to the Last Available Data (AUEClast)	2394.21 units on a scale * hour Standard Error 65.274	2661.43 units on a scale * hour Standard Error 84.274	2422.37 units on a scale * hour Standard Error 85.855	2444.4 units on a scale * hour Standard Error 83.580	2744.86 units on a scale * hour Standard Error 76.342	2759.57 units on a scale * hour Standard Error 74.589

SECONDARY outcome

Timeframe: Up to 1 hour post-dose (Assessments were made at the following timepoints after each treatment for this outcome measure: 0, 0.25, 0.5, and 1 hour)

Population: Modified completer population

Area under the effect-time profile from time 0 to 1 hour post-dose for the "Drug liking" visual analog scale which assesses how much a participant likes or dislikes a drug effect at the time the question ("at this moment, my liking this drug is") is being asked. It is scored using a 100 mm visual analogue scale (VAS), where 0 mm = "Strong Disliking", 50 mm = "Neither Like nor Dislike", and 100 mm = "Strong Liking"

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Bipolar VAS for "Drug Liking": Area Under the Effect Curve to 1 Hour (AUEC1)	50.17 units on a scale * hour Standard Error 0.317	58.86 units on a scale * hour Standard Error 1.478	51.28 units on a scale * hour Standard Error 1.440	50.61 units on a scale * hour Standard Error 0.568	57.02 units on a scale * hour Standard Error 1.771	55.76 units on a scale * hour Standard Error 1.390

SECONDARY outcome

Timeframe: Up to 2 hours after treatments (Assessments were made at the following timepoints after each treatment for this outcome measure: 0, 0.25, 0.5, 1, 1.5, and 2 hours)

Population: Modified completer population

Area under the effect-time profile from time 0 to 2 hours post-dose for the "Drug liking" visual analog scale which assesses how much a participant likes or dislikes a drug effect at the time the question ("at this moment, my liking this drug is") is being asked. It is scored using a 100 mm visual analogue scale (VAS), where 0 mm = "Strong Disliking", 50 mm = "Neither Like nor Dislike", and 100 mm = "Strong Liking"

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Bipolar VAS for "Drug Liking": Area Under the Effect Curve to 2 Hours (AUEC2)	102.62 units on a scale * hour Standard Error 1.791	140.44 units on a scale * hour Standard Error 4.434	105.20 units on a scale * hour Standard Error 4.017	107.19 units on a scale * hour Standard Error 2.449	138.72 units on a scale * hour Standard Error 4.340	133.84 units on a scale * hour Standard Error 4.010

SECONDARY outcome

Timeframe: up to 3 hours after treatments (Assessments were made at the following timepoints after each treatment for this outcome measure: 0, 0.25, 0.5, 1, 1.5, 2, 2.5, and 3 hours)

Population: Modified completer population

Area under the effect-time profile from time 0 to 3 hours post-dose for the "Drug liking" visual analog scale which assesses how much a participant likes or dislikes a drug effect at the time the question ("at this moment, my liking this drug is") is being asked. It is scored using a 100 mm visual analogue scale (VAS), where 0 mm = "Strong Disliking", 50 mm = "Neither Like nor Dislike", and 100 mm = "Strong Liking"

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Bipolar VAS for "Drug Liking": Area Under the Effect Curve to 3 Hours (AUEC3)	155.48 units on a scale * hour Standard Error 3.651	219.31 units on a scale * hour Standard Error 7.614	161.07 units on a scale * hour Standard Error 6.535	164.03 units on a scale * hour Standard Error 4.819	223.22 units on a scale * hour Standard Error 7.326	214.99 units on a scale * hour Standard Error 6.567

SECONDARY outcome

Timeframe: Up to 4 hours after treatments (Assessments were made at the following timepoints after each treatment for this outcome measure: 0, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, and 4 hours)

Population: Modified completer population

Area under the effect-time profile from time 0 to 4 hours post-dose for the "Drug liking" visual analog scale which assesses how much a participant likes or dislikes a drug effect at the time the question ("at this moment, my liking this drug is") is being asked. It is scored using a 100 mm visual analogue scale (VAS), where 0 mm = "Strong Disliking", 50 mm = "Neither Like nor Dislike", and 100 mm = "Strong Liking"

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Bipolar VAS for "Drug Liking": Area Under the Effect Curve to 4 Hours (AUEC4)	208.32 units on a scale * hour Standard Error 5.171	294.28 units on a scale * hour Standard Error 10.329	214.53 units on a scale * hour Standard Error 8.878	220.08 units on a scale * hour Standard Error 6.896	305.08 units on a scale * hour Standard Error 10.423	293.99 units on a scale * hour Standard Error 8.810

SECONDARY outcome

Timeframe: Up to 8 hours after treatments (Assessments were made at the following timepoints after each treatment for this outcome measure: 0, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, and 8 hours)

Population: Modified completer population

Area under the effect-time profile from time 0 to 8 hours post-dose for the "Drug liking" visual analog scale which assesses how much a participant likes or dislikes a drug effect at the time the question ("at this moment, my liking this drug is") is being asked. It is scored using a 100 mm visual analogue scale (VAS), where 0 mm = "Strong Disliking", 50 mm = "Neither Like nor Dislike", and 100 mm = "Strong Liking"

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Bipolar VAS for "Drug Liking": Area Under the Effect Curve to 8 Hours (AUEC8)	411.58 units on a scale * hour Standard Error 12.224	551.53 units on a scale * hour Standard Error 19.517	421.12 units on a scale * hour Standard Error 17.144	438.30 units on a scale * hour Standard Error 13.862	599.96 units on a scale * hour Standard Error 22.312	574.98 units on a scale * hour Standard Error 18.952

SECONDARY outcome

Timeframe: up to 48 hours after treatments

Population: Modified completer population

Maximum effect on the 100 mm visual analog scale for the question "I am feeling high" where 0 = "not at all" and 100 = "extremely"

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Unipolar VAS for "High" - Maximum Effect (Emax)	13.45 Score on a 100 mm scale Standard Error 4.854	77.36 Score on a 100 mm scale Standard Error 5.8160	28.61 Score on a 100 mm scale Standard Error 6.551	25.21 Score on a 100 mm scale Standard Error 6.412	81.86 Score on a 100 mm scale Standard Error 5.620	88.74 Score on a 100 mm scale Standard Error 4.210

SECONDARY outcome

Timeframe: up to 48 hours after treatments

Population: Modified completer population

Time after dosing when the maximum effect for "High" VAS is reached

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Unipolar VAS for "High": Time to Maximum Effect (TEmax)	0.25 hours Interval 0.2 to 8.0	1.00 hours Interval 0.3 to 4.0	0.26 hours Interval 0.2 to 8.0	0.27 hours Interval 0.1 to 144.9	1.00 hours Interval 0.2 to 48.1	1.50 hours Interval 0.2 to 4.1

SECONDARY outcome

Timeframe: Up to 48 hours after treatments (Assessments were made at the following timepoints after each treatment: 0, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 12, 24, 36, and 48 hours)

Population: Modified completer population

Area under the effect-time profile from time 0 to the time of the last available data for the "High" visual analog scale which measures on a 100 mm visual analog scale the subject's response to the question "I am feeling high" where 0 = "not at all" and 100 ="extremely"

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Area Under the Effect Curve for "High" VAS (AUEClast)	33.45 units on a scale * hour Standard Error 14.904	321.75 units on a scale * hour Standard Error 46.346	86.41 units on a scale * hour Standard Error 31.541	123.74 units on a scale * hour Standard Error 50.060	512.08 units on a scale * hour Standard Error 66.299	425.01 units on a scale * hour Standard Error 52.651

SECONDARY outcome

Timeframe: Up to 48 hours after treatments (Assessments were made at the following timepoints after each treatment for this outcome measure: 24, 36, and 48 hours)

Population: Modified completer population

100 mm visual analog scale at 24, 36, and 48 hours post-dose for the question "I would take this drug again" where 0 = "definitely not", 50 = "neutral", and 100 = "definitely so". The data from the 24, 36, and 48 hours postdose measurements were combined into a single overall model-adjusted value for 24 to 48 hours post-treatment timeframe by estimation from a mixed model with treatment, period, treatment sequence, time, and treatment*time as fixed effects, subject nested within sequence as a random effect. The compound symmetric covariance matrix was employed. Data from all time points were included

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Bipolar VAS for "Take Drug Again"	53.43 Score on a 100 mm scale Standard Error 2.928	72.16 Score on a 100 mm scale Standard Error 2.918	55.19 Score on a 100 mm scale Standard Error 2.942	58.05 Score on a 100 mm scale Standard Error 2.935	79.16 Score on a 100 mm scale Standard Error 2.940	77.85 Score on a 100 mm scale Standard Error 2.910

SECONDARY outcome

Timeframe: Up to 48 hours after treatments (Assessments were made at the following timepoints after each treatment for this outcome measure: 24, 36, and 48 hours)

Population: Modified completer population

100 mm visual analog scale at 24, 36, and 48 hours post-dose for the question "Overall, my liking for this drug is" where 0 = "definitely not", 50 = "neutral", and 100 = "definitely so". The data from the 24, 36, and 48 hours postdose measurements were combined into a single overall model-adjusted value for 24 to 48 hours post-treatment timeframe by estimation from a mixed model with treatment, period, treatment sequence, time, and treatment*time as fixed effects, subject nested within sequence as a random effect. The compound symmetric covariance matrix was employed. Data from all time points were included

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Bipolar VAS for "Overall Drug Liking"	51.75 Score on a 100 mm scale Standard Error 2.895	72.06 Score on a 100 mm scale Standard Error 2.886	54.40 Score on a 100 mm scale Standard Error 2.909	58.25 Score on a 100 mm scale Standard Error 2.902	75.90 Score on a 100 mm scale Standard Error 2.907	79.94 Score on a 100 mm scale Standard Error 2.878

SECONDARY outcome

Timeframe: up to 48 hours after treatments

Population: Modified completer population

100 mm visual analog scale for the question "At this moment, I can feel good drug effects" where 0 = "not at all" and 100 = "extremely"

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Unipolar VAS for "Good Drug Effect"	2.54 Score on a 100 mm scale Standard Error 2.123	27.91 Score on a 100 mm scale Standard Error 2.117	6.13 Score on a 100 mm scale Standard Error 2.117	8.73 Score on a 100 mm scale Standard Error 2.120	34.72 Score on a 100 mm scale Standard Error 2.119	32.71 Score on a 100 mm scale Standard Error 2.113

SECONDARY outcome

Timeframe: up to 48 hours after treatments

Population: Modified completer population

100 mm visual analog scale for the question "At this moment, I can feel bad drug effects" where 0 = "not at all" and 100 = "extremely"

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Unipolar VAS for "Bad Drug Effect"	0.19 Score on a 100 mm scale Standard Error 1.211	4.41 Score on a 100 mm scale Standard Error 1.209	0.82 Score on a 100 mm scale Standard Error 1.209	0.97 Score on a 100 mm scale Standard Error 1.210	4.10 Score on a 100 mm scale Standard Error 1.210	3.41 Score on a 100 mm scale Standard Error 1.207

SECONDARY outcome

Timeframe: up to 48 hours after treatments

Population: Modified completer population

100 mm visual analog scale for the question "At this moment, I can feel any drug effects" where 0 = "not at all" and 100 = "extremely"

Outcome measures

Measure	Placebo n=42 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=42 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=42 Participants Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Unipolar VAS for "Any Drug Effect"	3.77 Score on a 100 mm scale Standard Error 2.167	28.46 Score on a 100 mm scale Standard Error 2.161	6.63 Score on a 100 mm scale Standard Error 2.162	7.88 Score on a 100 mm scale Standard Error 2.164	34.34 Score on a 100 mm scale Standard Error 2.163	33.76 Score on a 100 mm scale Standard Error 2.158

SECONDARY outcome

Timeframe: Up to 48 hours after treatments (concentrations were measured at the following timepoints after each treatment for this outcome measure: 0, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 12, 24, 36, and 48 hours)

Population: Pharmacokinetic population: all enrolled participants who received study medication and have pharmacokinetic data for the parameters of interest.

Maximum plasma concentration of gabapentin

Outcome measures

Measure	Placebo n=51 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=52 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=52 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=52 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Cmax of Gabapentin	4.16 micrograms/milliliter Standard Deviation 1.422	6.07 micrograms/milliliter Standard Deviation 1.951	4.17 micrograms/milliliter Standard Deviation 1.121	6.18 micrograms/milliliter Standard Deviation 1.443	—	—

SECONDARY outcome

Timeframe: Up to 48 hours after treatments (concentrations were measured at the following timepoints after each treatment for this outcome measure: 0, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 12, 24, 36, and 48 hours)

Population: Pharmacokinetic population: all enrolled participants who received study medication and have pharmacokinetic data for the parameters of interest

Time when the maximum concentration of gabapentin is reached

Outcome measures

Measure	Placebo n=51 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=52 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=52 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=52 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Tmax of Gabapentin	3.13 Hours Interval 1.2 to 6.1	3.13 Hours Interval 1.6 to 6.1	3.13 Hours Interval 1.2 to 8.1	3.13 Hours Interval 1.2 to 8.2	—	—

SECONDARY outcome

Timeframe: Up to 48 hours after treatments (concentrations were measured at the following timepoints after each treatment for this outcome measure: 0, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 12, 24, 36, and 48 hours)

Population: Pharmacokinetic population: all enrolled participants who received study medication and have pharmacokinetic data for the parameters of interest

Area under the plasma concentration/time curve from time 0 extrapolated to infinity time of gabapentin

Outcome measures

Measure	Placebo n=51 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=52 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=52 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=52 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
AUCinf of Gabapentin	41.42 micrograms*hour/milliliter Standard Deviation 11.798	65.38 micrograms*hour/milliliter Standard Deviation 18.854	48.58 micrograms*hour/milliliter Standard Deviation 12.009	75.18 micrograms*hour/milliliter Standard Deviation 18.431	—	—

SECONDARY outcome

Timeframe: Up to 48 hours after treatment (concentrations were measured at the following timepoints after each treatment for this outcome measure: 0, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 12, 24, 36, and 48 hours)

Population: Pharmacokinetic population: all enrolled participants who received study medication and have pharmacokinetic data for the parameters of interes

Area under the plasma concentration/time profile from time 0 to the time of the last quantifiable concentration of gabapentin

Outcome measures

Measure	Placebo n=51 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=52 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=52 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=52 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
AUClast of Gabapentin	39.76 micrograms*hour/milliliter Standard Deviation 11.856	61.42 micrograms*hour/milliliter Standard Deviation 19.900	47.31 micrograms*hour/milliliter Standard Deviation 12.142	72.73 micrograms*hour/milliliter Standard Deviation 17.781	—	—

SECONDARY outcome

Timeframe: Up to 48 hours after treatments (concentrations were measured at the following timepoints after each treatment for this outcome measure: 0, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 12, 24, 36, and 48 hours)

Population: Pharmacokinetic population: all enrolled participants who received study medication and have pharmacokinetic data for the parameters of interest

Half-life (t½) of gabapentin

Outcome measures

Measure	Placebo n=51 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=51 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=52 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=52 Participants Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Half-life (t½) of Gabapentin	9.14 Hours Standard Deviation 10.846	10.62 Hours Standard Deviation 7.674	8.20 Hours Standard Deviation 3.551	9.19 Hours Standard Deviation 3.596	—	—

SECONDARY outcome

Timeframe: Up to 48 hours after treatments (concentrations were measured at the following timepoints after each treatment for this outcome measure: 0, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 12, 24, 36, and 48 hours)

Population: Pharmacokinetic population: all enrolled participants who received study medication and have pharmacokinetic data for the parameters of interest

Maximum plasma concentration of Oxycodone

Outcome measures

Measure	Placebo n=51 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=51 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=50 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Cmax of Oxycodone	44.92 nanograms/milliliter Standard Deviation 17.336	43.82 nanograms/milliliter Standard Deviation 14.144	40.79 nanograms/milliliter Standard Deviation 14.809	—	—	—

SECONDARY outcome

Timeframe: Up to 48 hours after treatments (concentrations were measured at the following timepoints after each treatment for this outcome measure: 0, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 12, 24, 36, and 48 hours)

Population: Pharmacokinetic population: all enrolled participants who received study medication and have pharmacokinetic data for the parameters of interest

Time when the maximum concentration of Oxycodone is reached

Outcome measures

Measure	Placebo n=51 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=51 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=50 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Tmax of Oxycodone	1.15 hours Interval 0.6 to 8.1	1.15 hours Interval 0.6 to 5.9	1.63 hours Interval 0.6 to 3.6	—	—	—

SECONDARY outcome

Timeframe: Up to 48 hours after treatments (concentrations were measured at the following timepoints after each treatment for this outcome measure: 0, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 12, 24, 36, and 48 hours)

Population: Pharmacokinetic population: all enrolled participants who received study medication and have pharmacokinetic data for the parameters of interest

Area under the plasma concentration/time curve from time 0 extrapolated to infinity time of Oxycodone

Outcome measures

Measure	Placebo n=51 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=51 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=49 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
AUCinf of Oxycodone	233.29 nanograms*hour/milliliter Standard Deviation 64.369	228.40 nanograms*hour/milliliter Standard Deviation 71.854	234.94 nanograms*hour/milliliter Standard Deviation 77.115	—	—	—

SECONDARY outcome

Timeframe: Up to 48 hours after treatments (concentrations were measured at the following timepoints after each treatment for this outcome measure: 0, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 12, 24, 36, and 48 hours)

Population: Pharmacokinetic population: all enrolled participants who received study medication and have pharmacokinetic data for the parameters of interest

Area under the plasma concentration/time profile from time 0 to the time of the last quantifiable concentration of Oxycodone

Outcome measures

Measure	Placebo n=51 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=51 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=50 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
AUClast of Oxycodone	229.31 nanograms*hour/milliliter Standard Deviation 64.935	224.79 nanograms*hour/milliliter Standard Deviation 71.748	234.65 nanograms*hour/milliliter Standard Deviation 80.068	—	—	—

SECONDARY outcome

Timeframe: Up to 48 hours after treatments (concentrations were measured at the following timepoints after each treatment for this outcome measure: 0, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 12, 24, 36, and 48 hours)

Population: Pharmacokinetic population: all enrolled participants who received study medication and have pharmacokinetic data for the parameters of interest

Half-life (t½) of Oxycodone

Outcome measures

Measure	Placebo n=51 Participants Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=51 Participants Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=49 Participants Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Half-life (t½) of Oxycodone	4.12 hours Interval 2.6 to 6.2	3.84 hours Interval 2.2 to 6.1	3.90 hours Interval 2.4 to 10.7	—	—	—

Adverse Events

Placebo

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Oxycodone HCl 20 mg Single Dose

Serious events: 0 serious events

Other events: 4 other events

Deaths: 0 deaths

Gabapentin 600 mg Single Dose

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Gabapentin 1200 mg Single Dose

Serious events: 0 serious events

Other events: 2 other events

Deaths: 0 deaths

Gabapentin 600 mg and Oxycodone HCl 20 mg

Serious events: 0 serious events

Other events: 4 other events

Deaths: 0 deaths

Gabapentin 1200 mg and Oxycodone HCl 20 mg

Serious events: 0 serious events

Other events: 2 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Measure	Placebo n=53 participants at risk Participants received a single oral dose of a placebo that looks like gabapentin and a placebo that looks like oxycodone HCl	Oxycodone HCl 20 mg Single Dose n=52 participants at risk Participants received a single oral dose of oxycodone HCl 20 mg and a placebo that looks like gabapentin	Gabapentin 600 mg Single Dose n=51 participants at risk Participants received a single oral dose of gabapentin 600 mg and a placebo that looks like oxycodone HCl	Gabapentin 1200 mg Single Dose n=52 participants at risk Participants received a single oral dose of gabapentin 1200 mg and a placebo that looks like oxycodone HCl	Gabapentin 600 mg and Oxycodone HCl 20 mg n=52 participants at risk Participants received a single oral dose of gabapentin 600 mg and oxycodone HCl 20 mg	Gabapentin 1200 mg and Oxycodone HCl 20 mg n=52 participants at risk Participants received a single oral dose of gabapentin 1200 mg and oxycodone HCl 20 mg
Gastrointestinal disorders Nausea	0.00% 0/53 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit	7.7% 4/52 • Number of events 4 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit	0.00% 0/51 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit	0.00% 0/52 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit	7.7% 4/52 • Number of events 4 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit	3.8% 2/52 • Number of events 2 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit
Gastrointestinal disorders Vomiting	0.00% 0/53 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit	0.00% 0/52 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit	0.00% 0/51 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit	1.9% 1/52 • Number of events 1 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit	0.00% 0/52 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit	0.00% 0/52 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit
Injury, poisoning and procedural complications Muscle strain	0.00% 0/53 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit	0.00% 0/52 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit	0.00% 0/51 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit	1.9% 1/52 • Number of events 1 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit	0.00% 0/52 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit	0.00% 0/52 • During the entire Treatment Phase of the study, which encompassed the time interval from admission of the subject to their first Treatment Period until 28 days after study drug dosing in their last (6th) Treatment Period, including the washout in between Treatment Periods. The total duration of the Treatment Phase for each subject was dependent on visit scheduling and whether the subject completed all 6 treatment periods, and it lasted up to approximately 13 weeks. Adverse events that occur during the washout interval between treatment visits or during the follow up after the final study drug dose were counted under the previous treatment visit

Additional Information

Dik WH Ng

Viatris

Phone: +44 (0)1304 626895

Email: dik.ng@viatris.com

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place

Restriction type: OTHER