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PF-06372865 In Subjects With Chronic Low Back Pain

A Randomized, Double Blind, Placebo- And Active-controlled, 4 Week, Multi-center, Parallel Group Study Assessing The Analgesic Effect, Safety And Tolerability Of Pf-06372865 In Subjects With Chronic Low Back Pain Using Naproxen As Positive Control

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02262754
Enrollment
302
Registered
2014-10-13
Start date
2014-10-31
Completion date
2015-08-31
Last updated
2017-01-04

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

Conditions

Chronic Low Back Pain

Brief summary

PF-06372865 In Subjects With Chronic Low Back Pain

Interventions

Dose level 1 daily dosing BID for 1 week followed by dose level 2 daily BID for 3 weeks

DRUGPlacebo

Placebo for PF-06372865 and placebo for naproxen daily

DRUGNaproxen

500 mg BID for 4 weeks

Sponsors

Pfizer
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender
ALL
Age
18 Years to 75 Years
Healthy volunteers
No

Inclusion criteria

\-

Exclusion criteria

\-

Design outcomes

Primary

MeasureTime frameDescription
Change From Baseline in Daily Low Back Pain Intensity (LBPI) Score as Measured by an 11-point Numeric Rating Scale (NRS) at Week 4Baseline, Week 4Daily average low back pain was assessed on an 11-point numeric rating scale (NRS). Participants described their average low back pain during the past 24 hours on a scale ranging from 0 (no pain) to 10 (worst possible pain), where higher scores indicate higher pain. Baseline value was calculated as the mean of the scores over the last 7 days in the placebo run-in period, prior to randomization. Post-baseline weekly scores were calculated based on the mean of the scores over the 7 days prior to and including the day at the end of the corresponding week.
Number of Participants With Treatment-Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)Baseline up to 28 days after the last dose of study treatment (Day 56)An AE was any untoward medical occurrence in a participant who received study treatment without regard to possibility of causal relationship. The SAE was an AE resulting in any of the following outcomes or deemed significant for any other reason: death, initial or prolonged inpatient hospitalization, life-threatening experience (immediate risk of dying), persistent or significant disability or incapacity, congenital anomaly. Treatment-emergent are events between first dose of study drug and up to 28 days after last dose that were absent before treatment or that worsened relative to pretreatment state. AEs included both serious and non-serious adverse events.
Number of Participants With Laboratory AbnormalitiesBaseline up to 28 days after the last dose of study treatment (Day 56)Abnormality criteria included: hemoglobin, hematocrit and red blood cells (RBCs) (less than \[\<\] 0.8\*lower limit of normal \[LLN\]); white blood cells (WBC) (\<0.6\*LLN, greater than \[\>\] 1.5\*upper limit of normal \[ULN\]); MCV, MCH, MCHC (\<0.9\*LLN, \>1.1\*ULN); platelets (\<0.5\*LLN\>, \>1.75\*ULN); neutrophils, lymphocytes(\<0.8\*LLN, \>1.2\*ULN); eosinophils, basophils, monocytes (\>1.2\*ULN); total bilirubin (\>1.5\*ULN); aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase (\>3\*ULN); total protein, albumin (\<0.8\*LLN, \>1.2\*ULN); creatinine, blood urea nitrogen (\>1.3\*ULN); glucose (\<0.6\*LLN, \>1.5\*ULN); uric acid (\>1.2\*ULN); sodium, potassium, chloride, calcium, bicarbonate (\<0.9\*LLN, \>1.1\*ULN); urine pH (\<4.5, \>8); qualitative urine glucose, ketones, protein, blood values (greater than or equal to \[\>=\] 1) in urine dipstick test; urine RBC, WBC (\>=20); hyaline casts (\>1), bacteria (\>20).
Number of Participants With Vital Sign AbnormalitiesBaseline up to Follow-up (44 days)Participants who met the criteria for abnormal findings in vital signs data were reported. Criteria for abnormalities in vital signs: supine systolic blood pressure (SBP) \<90 millimeter of mercury (mmHg), supine diastolic BP (DBP) \<50 mmHg, supine pulse rate \<40 beats per minute (bpm) or \>120 bpm. Maximum increase or decrease from baseline in supine SBP \>=30 mmHg and maximum increase or decrease from baseline in supine DBP \>=20 mmHg.
Number of Participants With Electrocardiogram (ECG) AbnormalitiesBaseline up to Follow-up (44 days)Participants with abnormal ECG findings were reported. Criteria for potential clinical concern in ECG parameters: maximum (max.) PR interval of \>=300 milliseconds (msec), maximum QRS interval \>=140 msec, maximum QTCF interval (Fridericia's Correction) of 450 to \<480 msec, 480 to \<500 msec and \>=500 msec, maximum of \>=25 percent (%) increase from baseline (IFB) value of \>200 msec and \>=50% for baseline value of less than or equal to (\<=) 200 msec for PR interval, maximum increase from baseline of \>=50% for QRS interval, maximum increase from baseline of \>=30 msec to \<60 msec and maximum increase from baseline of \>60 msec in QTCF interval (Fridericia's Correction).
Number of Participants With Categorical Scores on the Columbia Suicide Severity Rating Scale (C-SSRS)Screening, Baseline, Week 1, 2, 3, 4The C-SSRS (mapped to Columbia Classification Algorithm of Suicide Assessment \[C-CASA\]) is an interview-based rating scale to systematically assess suicidal ideation and suicidal behavior. C-SSRS assessed whether participant experienced following: completed suicide =1, suicide attempt =2 (response of Yes on actual attempt), preparatory acts toward imminent suicidal behavior =3 (Yes on preparatory acts or behavior), suicidal ideation =4 (Yes on wish to be dead, non-specific active suicidal thoughts, active suicidal ideation with methods without intent to act or some intent to act, without specific plan or with specific plan and intent), any suicidal behavior or ideation, self-injurious behavior =7 (Yes on Has participant engaged in non-suicidal self-injurious behavior).
Change From End of Treatment Visit in Physician's Withdrawal Checklist (PWC) Score at Follow-up VisitEnd of treatment (Day 30), follow-up (Day 44)PWC is a 20 item physician rated interview to measure anxiolytic drug withdrawal-related signs and symptoms. Each individual item score ranges from 0 (not present) to 3 (severe), where higher scores = more affected condition. PWC total score range from 0 (not present) to 60 (severe), where higher score = more affected condition. Change: score at follow-up visit minus score at the end of treatment visit.

Secondary

MeasureTime frameDescription
Number of Days Participants Used the Rescue MedicationWeek 1, 2, 3, 4The number of days for which the participants used the rescue medication were reported. Participants recorded the usage of acetaminophen rescue medication in the daily diary.
Amount of Rescue Medication Used by the ParticipantsWeek 1, 2, 3, 4The amount of rescue medication (Acetaminophen \[paracetamol\]) used was reported. Participants were permitted to use any commercial product of acetaminophen tablet/caplet/capsule.
Change From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 1, 2, and 3Baseline, Week 1, 2, 3Each participant assessed his or her own disability due to low back pain using the RMDQ worksheet. The RMDQ total score was calculated as the total number of statements that were checked; the RMDQ total possible scores ranges from 0 to 24, with higher scores indicating greater disability.
Change From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Baseline, Week 2, Week 4This test assesses verbal learning and memory. Participants are given a list of 12 words and asked to repeat as many words as they can recall during 3 separate learning trials. The total recall score ranges from 0 (no memory) to 36 (best memory) while the delayed recall trial score ranges from 0 (no memory) to 12 (best memory); higher scores indicated greater verbal learning and recall.
Chronic Low Back Pain (CLBP) Responder Index AnalysisWeek 1, 2, 3, 4Participants were successful responders if they had any of the following: \>=30 percent reduction in mean daily average LBPI from baseline to particular week; decrease of \>=30 percent in participant's global assessment of low back pain (disease activity) from baseline to particular week or no worsening (increase) in RMDQ total score from baseline to particular week.
Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2 3 and 4Baseline, Week 1, 2, 3, 4Average back pain was assessed with an 11-point NRS ranging from 0 (no pain) to 10 (worst possible pain), where higher scores indicated higher pain. Participants described their average low back pain during the past 24 hours by choosing the appropriate number from 0 to 10.
Patient Global Impression of Change (PGI-C) ScoreWeek 1, 2, 3, 4PGI-C was a participant rated instrument to measure participant's assessment of change in his or her overall status since the previous visit on a 7-point scale; ranging from 1 (very much improved) to 7 (very much worse), where higher scores indicated more worsening.
Number of Participants With Global Evaluation of Study Medication (GESM) at Week 4Week 4Participants rated their study treatment by GESM questionnaire. It was a qualitative measure of efficacy utilizing a 4-point Likert scale ranging from 1 (poor) to 4 (excellent), where higher score indicated a better overall response to the treatment. Number of participants who reported a particular score had been reported.
Plasma Concentration of PF-06372865Baseline, Week 1, 2, 3, 4Data was calculated by setting concentration values below the lower limit of quantification (LLOQ) to zero. The LLOQ was \<0.0100 nanogram per milliliter (ng/mL).
Plasma Concentration of NaproxenBaseline, Week 1, 2, 3, 4Data was calculated by setting concentration values below the LLOQ to zero. The LLOQ was \<1000 ng/mL.
Change From Baseline in Participant's Global Assessment (PtGA) of Low Back Pain Score at Week 1, 2, 3 and 4Baseline, Week 1, 2, 3, 4Participant rated 5-point Likert scale ranging from 0 (no pain) to 4 (worst possible pain) with a higher score indicating greater level of pain.
Percent Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2, 3 and 4Baseline, Week 1, 2, 3, 4Average back pain was assessed with an 11-point NRS ranging from 0 (no pain) to 10 (worst possible pain), where higher scores indicated higher pain. Participants described their average low back pain during the past 24 hours by choosing the appropriate number from 0 to 10.
Number of Participants With Sustained Response Rates in Daily Average LBPI NRS Scores at Greater Than or Equal to (>=) 30 Percent and >=50 Percent Reduction From BaselineBaseline up to Week 4Average back pain was assessed with an 11-point NRS ranging from 0 (no pain) to 10 (worst possible pain), where higher scores indicated higher pain. Participants described their average low back pain during the past 24 hours by choosing the appropriate number from 0 to 10. Percentage of reduction from baseline in the daily average LBPI NRS score was calculated as: (\[daily value - baseline value\] divided by baseline value) multiplied by 100. Number of participants with sustained response rates (for a minimum of 4 consecutive days) in the daily average LBPI NRS scores that were at \>=30 percent and \>=50 percent reduced from baseline were reported.
Number of Participants Withdrawn Due to Lack of EfficacyBaseline up to Week 4Participants withdrew from the study due to lack of efficacy (insufficient clinical response) were reported.
Change From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 4Baseline, Week 4Each participant assessed his or her own disability due to low back pain using the RMDQ worksheet. The RMDQ total score was calculated as the total number of statements that were checked; the RMDQ total possible scores ranges from 0 to 24, with higher scores indicating greater disability.
Time to Withdrawal Due to Lack of EfficacyBaseline up to Week 4Kaplan Meier and Cox Proportional Hazards analyses were to be used to compute the time to withdrawal due to lack of efficacy. Withdrawal due to lack of efficacy was identified from the participant summary case report form (CRF) page and where reason was identified as Insufficient Clinical Response. Time to withdrawal was calculated as Date of withdrawal - Date of Randomization.
Number of Participants Using Rescue MedicationWeek 1, 2, 3, 4Participants were permitted to use any commercial product (tablet/caplet/capsule) of acetaminophen (paracetamol) 500 mg as a rescue medication. Number of participants who used rescue medication were reported.

Countries

United States

Participant flow

Participants by arm

ArmCount
Placebo
Participants received placebo matched to PF-06372865 tablets along with Naproxen 500 milligram (mg) tablets orally, twice daily for four weeks.
74
PF-06372865
Participants received PF-06372865 2.5 mg tablets along with placebo matched to Naproxen tablets orally, twice daily for one week followed by PF-06372865 7.5 mg tablets along with placebo matched to Naproxen tablets orally, twice daily for three weeks.
74
Naproxen
Participants received Naproxen 500 mg tablets along with placebo matched to PF-06372865 tablets orally, twice daily for four weeks.
74
Total222

Withdrawals & dropouts

PeriodReasonFG000FG001FG002
Overall StudyAdverse Event340
Overall StudyLack of Efficacy201
Overall StudyLost to Follow-up001
Overall StudyNo longer meets eligibility criteria010
Overall StudyOther402
Overall StudyProtocol Violation100
Overall StudyStudy terminated by sponsor544
Overall StudyWithdrawal by Subject101

Baseline characteristics

CharacteristicPlaceboPF-06372865NaproxenTotal
Age, Continuous51.1 years
STANDARD_DEVIATION 12.1
49.7 years
STANDARD_DEVIATION 13.8
51.6 years
STANDARD_DEVIATION 13.1
50.8 years
STANDARD_DEVIATION 12.9
Gender
FEMALE
38 Participants39 Participants37 Participants114 Participants
Gender
MALE
36 Participants35 Participants37 Participants108 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
deaths
Total, all-cause mortality
— / —— / —— / —
other
Total, other adverse events
25 / 7434 / 7426 / 74
serious
Total, serious adverse events
1 / 741 / 742 / 74

Outcome results

Primary

Change From Baseline in Daily Low Back Pain Intensity (LBPI) Score as Measured by an 11-point Numeric Rating Scale (NRS) at Week 4

Daily average low back pain was assessed on an 11-point numeric rating scale (NRS). Participants described their average low back pain during the past 24 hours on a scale ranging from 0 (no pain) to 10 (worst possible pain), where higher scores indicate higher pain. Baseline value was calculated as the mean of the scores over the last 7 days in the placebo run-in period, prior to randomization. Post-baseline weekly scores were calculated based on the mean of the scores over the 7 days prior to and including the day at the end of the corresponding week.

Time frame: Baseline, Week 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment.

ArmMeasureValue (MEAN)Dispersion
PlaceboChange From Baseline in Daily Low Back Pain Intensity (LBPI) Score as Measured by an 11-point Numeric Rating Scale (NRS) at Week 4-1.19 units on a scale90% Confidence Interval 1.351
PF-06372865Change From Baseline in Daily Low Back Pain Intensity (LBPI) Score as Measured by an 11-point Numeric Rating Scale (NRS) at Week 4-1.03 units on a scale90% Confidence Interval 1.091
NaproxenChange From Baseline in Daily Low Back Pain Intensity (LBPI) Score as Measured by an 11-point Numeric Rating Scale (NRS) at Week 4-1.45 units on a scale90% Confidence Interval 1.401
Comparison: An analysis of covariance (ANCOVA) model within an outlier robust Bayesian framework was applied. Baseline was included as a fixed effect. An informative N (-2.36, 0.542\^2) prior for the placebo effect was assumed. Non informative prior distributions were assumed for the rest of the model parameters. A last observation carried forward (LOCF) was used for missing data.90% CI: [-0.28, 0.6]
Comparison: An ANCOVA model within an outlier robust Bayesian framework was applied. Baseline was included as a fixed effect. An informative N (-2.36, 0.542\^2) prior for the placebo effect was assumed. Non informative prior distributions were assumed for the rest of the model parameters. A last observation carried forward LOCF was used for missing data.90% CI: [-0.02, 0.87]
Comparison: An ANCOVA model within an outlier robust Bayesian framework was applied. Baseline was included as a fixed effect. An informative N (-2.36, 0.542\^2) prior for the placebo effect was assumed. Non informative prior distributions were assumed for the rest of the model parameters. A last observation carried forward LOCF was used for missing data.90% CI: [-0.7, 0.18]
Primary

Change From End of Treatment Visit in Physician's Withdrawal Checklist (PWC) Score at Follow-up Visit

PWC is a 20 item physician rated interview to measure anxiolytic drug withdrawal-related signs and symptoms. Each individual item score ranges from 0 (not present) to 3 (severe), where higher scores = more affected condition. PWC total score range from 0 (not present) to 60 (severe), where higher score = more affected condition. Change: score at follow-up visit minus score at the end of treatment visit.

Time frame: End of treatment (Day 30), follow-up (Day 44)

Population: Safety analysis set included all participants who received at least 1 dose of study treatment.

ArmMeasureValue (LEAST_SQUARES_MEAN)Dispersion
PlaceboChange From End of Treatment Visit in Physician's Withdrawal Checklist (PWC) Score at Follow-up Visit-0.11 units on a scale90% Confidence Interval 1.351
PF-06372865Change From End of Treatment Visit in Physician's Withdrawal Checklist (PWC) Score at Follow-up Visit-0.34 units on a scale90% Confidence Interval 1.091
NaproxenChange From End of Treatment Visit in Physician's Withdrawal Checklist (PWC) Score at Follow-up Visit0.01 units on a scale90% Confidence Interval 1.401
Comparison: The ANCOVA model included treatment as fixed effects.90% CI: [-0.76, 0.3]
Comparison: The ANCOVA model included treatment as fixed effects.90% CI: [-0.41, 0.65]
Comparison: The ANCOVA model included treatment as fixed effects.90% CI: [-0.87, 0.17]
Primary

Number of Participants With Categorical Scores on the Columbia Suicide Severity Rating Scale (C-SSRS)

The C-SSRS (mapped to Columbia Classification Algorithm of Suicide Assessment \[C-CASA\]) is an interview-based rating scale to systematically assess suicidal ideation and suicidal behavior. C-SSRS assessed whether participant experienced following: completed suicide =1, suicide attempt =2 (response of Yes on actual attempt), preparatory acts toward imminent suicidal behavior =3 (Yes on preparatory acts or behavior), suicidal ideation =4 (Yes on wish to be dead, non-specific active suicidal thoughts, active suicidal ideation with methods without intent to act or some intent to act, without specific plan or with specific plan and intent), any suicidal behavior or ideation, self-injurious behavior =7 (Yes on Has participant engaged in non-suicidal self-injurious behavior).

Time frame: Screening, Baseline, Week 1, 2, 3, 4

Population: Data was not collected for this outcome measure as per study team's decision, since it was a semi-structured interview and was difficult to pull accurate scores from it.

Primary

Number of Participants With Electrocardiogram (ECG) Abnormalities

Participants with abnormal ECG findings were reported. Criteria for potential clinical concern in ECG parameters: maximum (max.) PR interval of \>=300 milliseconds (msec), maximum QRS interval \>=140 msec, maximum QTCF interval (Fridericia's Correction) of 450 to \<480 msec, 480 to \<500 msec and \>=500 msec, maximum of \>=25 percent (%) increase from baseline (IFB) value of \>200 msec and \>=50% for baseline value of less than or equal to (\<=) 200 msec for PR interval, maximum increase from baseline of \>=50% for QRS interval, maximum increase from baseline of \>=30 msec to \<60 msec and maximum increase from baseline of \>60 msec in QTCF interval (Fridericia's Correction).

Time frame: Baseline up to Follow-up (44 days)

Population: Safety analysis set included all participants who received at least 1 dose of study treatment. Here, n signifies the number of participants evaluable for the specific category.

ArmMeasureGroupValue (NUMBER)Dispersion
PlaceboNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QTCF Interval: 480 to <500 msec (n=72,74,72)0 participants
PlaceboNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QTCF Interval IFB: >=60 msec (n=72,74,72)3 participants
PlaceboNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. PR Interval IFB: >=25 or 50% (n=72, 74, 71)1 participants
PlaceboNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QTCF Interval: >=500 msec (n=72, 74, 72)0 participants
PlaceboNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. PR Interval: >=300 msec (n=72, 74, 72)0 participants 1.351
PlaceboNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QTCF Interval IFB: 30 to<60 msec (n=72,74,72)3 participants
PlaceboNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QTCF Interval: 450 to <480 msec (n=72,74,72)1 participants
PlaceboNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QRS Complex: >=140 msec (n=72, 74, 72)0 participants
PlaceboNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QRS Complex IFB: >=50% (n=72, 74, 72)1 participants
PF-06372865Number of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QTCF Interval: >=500 msec (n=72, 74, 72)0 participants
PF-06372865Number of Participants With Electrocardiogram (ECG) AbnormalitiesMax. PR Interval: >=300 msec (n=72, 74, 72)0 participants 1.091
PF-06372865Number of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QRS Complex: >=140 msec (n=72, 74, 72)0 participants
PF-06372865Number of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QTCF Interval: 450 to <480 msec (n=72,74,72)1 participants
PF-06372865Number of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QTCF Interval: 480 to <500 msec (n=72,74,72)1 participants
PF-06372865Number of Participants With Electrocardiogram (ECG) AbnormalitiesMax. PR Interval IFB: >=25 or 50% (n=72, 74, 71)0 participants
PF-06372865Number of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QRS Complex IFB: >=50% (n=72, 74, 72)0 participants
PF-06372865Number of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QTCF Interval IFB: 30 to<60 msec (n=72,74,72)4 participants
PF-06372865Number of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QTCF Interval IFB: >=60 msec (n=72,74,72)1 participants
NaproxenNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QTCF Interval: 450 to <480 msec (n=72,74,72)2 participants
NaproxenNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. PR Interval: >=300 msec (n=72, 74, 72)0 participants 1.401
NaproxenNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QRS Complex IFB: >=50% (n=72, 74, 72)1 participants
NaproxenNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QRS Complex: >=140 msec (n=72, 74, 72)1 participants
NaproxenNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QTCF Interval IFB: >=60 msec (n=72,74,72)0 participants
NaproxenNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QTCF Interval: >=500 msec (n=72, 74, 72)0 participants
NaproxenNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QTCF Interval: 480 to <500 msec (n=72,74,72)0 participants
NaproxenNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. QTCF Interval IFB: 30 to<60 msec (n=72,74,72)0 participants
NaproxenNumber of Participants With Electrocardiogram (ECG) AbnormalitiesMax. PR Interval IFB: >=25 or 50% (n=72, 74, 71)0 participants
Primary

Number of Participants With Laboratory Abnormalities

Abnormality criteria included: hemoglobin, hematocrit and red blood cells (RBCs) (less than \[\<\] 0.8\*lower limit of normal \[LLN\]); white blood cells (WBC) (\<0.6\*LLN, greater than \[\>\] 1.5\*upper limit of normal \[ULN\]); MCV, MCH, MCHC (\<0.9\*LLN, \>1.1\*ULN); platelets (\<0.5\*LLN\>, \>1.75\*ULN); neutrophils, lymphocytes(\<0.8\*LLN, \>1.2\*ULN); eosinophils, basophils, monocytes (\>1.2\*ULN); total bilirubin (\>1.5\*ULN); aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase (\>3\*ULN); total protein, albumin (\<0.8\*LLN, \>1.2\*ULN); creatinine, blood urea nitrogen (\>1.3\*ULN); glucose (\<0.6\*LLN, \>1.5\*ULN); uric acid (\>1.2\*ULN); sodium, potassium, chloride, calcium, bicarbonate (\<0.9\*LLN, \>1.1\*ULN); urine pH (\<4.5, \>8); qualitative urine glucose, ketones, protein, blood values (greater than or equal to \[\>=\] 1) in urine dipstick test; urine RBC, WBC (\>=20); hyaline casts (\>1), bacteria (\>20).

Time frame: Baseline up to 28 days after the last dose of study treatment (Day 56)

Population: Safety analysis set included all participants who received at least 1 dose of study treatment. Here, number of participants analyzed signifies those participants who were evaluable for this outcome measure.

ArmMeasureValue (NUMBER)
PlaceboNumber of Participants With Laboratory Abnormalities26 participants
PF-06372865Number of Participants With Laboratory Abnormalities44 participants
NaproxenNumber of Participants With Laboratory Abnormalities41 participants
Primary

Number of Participants With Treatment-Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)

An AE was any untoward medical occurrence in a participant who received study treatment without regard to possibility of causal relationship. The SAE was an AE resulting in any of the following outcomes or deemed significant for any other reason: death, initial or prolonged inpatient hospitalization, life-threatening experience (immediate risk of dying), persistent or significant disability or incapacity, congenital anomaly. Treatment-emergent are events between first dose of study drug and up to 28 days after last dose that were absent before treatment or that worsened relative to pretreatment state. AEs included both serious and non-serious adverse events.

Time frame: Baseline up to 28 days after the last dose of study treatment (Day 56)

Population: Safety analysis set included all participants who received at least 1 dose of study treatment.

ArmMeasureGroupValue (NUMBER)Dispersion
PlaceboNumber of Participants With Treatment-Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)AEs26 participants 1.351
PlaceboNumber of Participants With Treatment-Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)SAEs1 participants
PF-06372865Number of Participants With Treatment-Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)AEs34 participants 1.091
PF-06372865Number of Participants With Treatment-Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)SAEs1 participants
NaproxenNumber of Participants With Treatment-Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)AEs28 participants 1.401
NaproxenNumber of Participants With Treatment-Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)SAEs2 participants
Primary

Number of Participants With Vital Sign Abnormalities

Participants who met the criteria for abnormal findings in vital signs data were reported. Criteria for abnormalities in vital signs: supine systolic blood pressure (SBP) \<90 millimeter of mercury (mmHg), supine diastolic BP (DBP) \<50 mmHg, supine pulse rate \<40 beats per minute (bpm) or \>120 bpm. Maximum increase or decrease from baseline in supine SBP \>=30 mmHg and maximum increase or decrease from baseline in supine DBP \>=20 mmHg.

Time frame: Baseline up to Follow-up (44 days)

Population: Safety analysis set included all participants who received at least 1 dose of study treatment.

ArmMeasureGroupValue (NUMBER)Dispersion
PlaceboNumber of Participants With Vital Sign AbnormalitiesSupine SBP: <90 mmHg0 participants 1.351
PlaceboNumber of Participants With Vital Sign AbnormalitiesSupine DBP: <50 mmHg0 participants
PlaceboNumber of Participants With Vital Sign AbnormalitiesSupine pulse rate: <40 bpm0 participants
PlaceboNumber of Participants With Vital Sign AbnormalitiesSupine pulse rate: >120 bpm0 participants
PlaceboNumber of Participants With Vital Sign AbnormalitiesMaximum increase in Supine SBP: >=30 mmHg5 participants
PlaceboNumber of Participants With Vital Sign AbnormalitiesMaximum increase in Supine DBP: >=20 mmHg6 participants
PlaceboNumber of Participants With Vital Sign AbnormalitiesMaximum decrease in Supine SBP: >=30 mmHg1 participants
PlaceboNumber of Participants With Vital Sign AbnormalitiesMaximum decrease in Supine DBP: >=20 mmHg3 participants
PF-06372865Number of Participants With Vital Sign AbnormalitiesSupine pulse rate: <40 bpm0 participants
PF-06372865Number of Participants With Vital Sign AbnormalitiesMaximum decrease in Supine SBP: >=30 mmHg6 participants
PF-06372865Number of Participants With Vital Sign AbnormalitiesSupine pulse rate: >120 bpm0 participants
PF-06372865Number of Participants With Vital Sign AbnormalitiesMaximum increase in Supine SBP: >=30 mmHg0 participants
PF-06372865Number of Participants With Vital Sign AbnormalitiesMaximum increase in Supine DBP: >=20 mmHg3 participants
PF-06372865Number of Participants With Vital Sign AbnormalitiesSupine SBP: <90 mmHg1 participants 1.091
PF-06372865Number of Participants With Vital Sign AbnormalitiesSupine DBP: <50 mmHg1 participants
PF-06372865Number of Participants With Vital Sign AbnormalitiesMaximum decrease in Supine DBP: >=20 mmHg9 participants
NaproxenNumber of Participants With Vital Sign AbnormalitiesSupine pulse rate: <40 bpm0 participants
NaproxenNumber of Participants With Vital Sign AbnormalitiesSupine DBP: <50 mmHg0 participants
NaproxenNumber of Participants With Vital Sign AbnormalitiesSupine SBP: <90 mmHg0 participants 1.401
NaproxenNumber of Participants With Vital Sign AbnormalitiesSupine pulse rate: >120 bpm0 participants
NaproxenNumber of Participants With Vital Sign AbnormalitiesMaximum decrease in Supine SBP: >=30 mmHg4 participants
NaproxenNumber of Participants With Vital Sign AbnormalitiesMaximum increase in Supine DBP: >=20 mmHg4 participants
NaproxenNumber of Participants With Vital Sign AbnormalitiesMaximum increase in Supine SBP: >=30 mmHg1 participants
NaproxenNumber of Participants With Vital Sign AbnormalitiesMaximum decrease in Supine DBP: >=20 mmHg3 participants
Secondary

Amount of Rescue Medication Used by the Participants

The amount of rescue medication (Acetaminophen \[paracetamol\]) used was reported. Participants were permitted to use any commercial product of acetaminophen tablet/caplet/capsule.

Time frame: Week 1, 2, 3, 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment. Here, n signifies participants who were evaluable at the specified time point for each arm.

ArmMeasureGroupValue (MEAN)Dispersion
PlaceboAmount of Rescue Medication Used by the ParticipantsWeek 1 (n= 72, 70, 74)1388.9 mgStandard Deviation 2703.97
PlaceboAmount of Rescue Medication Used by the ParticipantsWeek 2 (n= 65, 68, 72)1030.8 mgStandard Deviation 1669.76
PlaceboAmount of Rescue Medication Used by the ParticipantsWeek 3 (n= 61, 65, 71)1172.1 mgStandard Deviation 1955.52
PlaceboAmount of Rescue Medication Used by the ParticipantsWeek 4 (n= 58, 62, 67)1101.7 mgStandard Deviation 2069.03
PF-06372865Amount of Rescue Medication Used by the ParticipantsWeek 4 (n= 58, 62, 67)1348.8 mgStandard Deviation 2925.65
PF-06372865Amount of Rescue Medication Used by the ParticipantsWeek 1 (n= 72, 70, 74)1621.8 mgStandard Deviation 4169.38
PF-06372865Amount of Rescue Medication Used by the ParticipantsWeek 3 (n= 61, 65, 71)1416.9 mgStandard Deviation 3552.05
PF-06372865Amount of Rescue Medication Used by the ParticipantsWeek 2 (n= 65, 68, 72)1594.1 mgStandard Deviation 3708.11
NaproxenAmount of Rescue Medication Used by the ParticipantsWeek 4 (n= 58, 62, 67)1489.2 mgStandard Deviation 3567.2
NaproxenAmount of Rescue Medication Used by the ParticipantsWeek 2 (n= 65, 68, 72)1920.5 mgStandard Deviation 4327.48
NaproxenAmount of Rescue Medication Used by the ParticipantsWeek 3 (n= 61, 65, 71)1740.5 mgStandard Deviation 4361.26
NaproxenAmount of Rescue Medication Used by the ParticipantsWeek 1 (n= 72, 70, 74)2064.5 mgStandard Deviation 4298.8
Secondary

Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2 3 and 4

Average back pain was assessed with an 11-point NRS ranging from 0 (no pain) to 10 (worst possible pain), where higher scores indicated higher pain. Participants described their average low back pain during the past 24 hours by choosing the appropriate number from 0 to 10.

Time frame: Baseline, Week 1, 2, 3, 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment. Here, n signifies participants who were evaluable at the specified time point for each arm.

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)Dispersion
PlaceboChange From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2 3 and 4Change at week 1 (n= 74, 74, 74)-0.50 units on a scale90% Confidence Interval 1.351
PlaceboChange From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2 3 and 4Change at week 2 (n= 65, 70, 72)-0.93 units on a scale
PlaceboChange From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2 3 and 4Change at week 3 (n= 62, 69, 70)-1.12 units on a scale
PlaceboChange From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2 3 and 4Change at week 4 (n= 59, 64, 66)-1.22 units on a scale
PF-06372865Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2 3 and 4Change at week 4 (n= 59, 64, 66)-1.14 units on a scale
PF-06372865Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2 3 and 4Change at week 1 (n= 74, 74, 74)-0.41 units on a scale90% Confidence Interval 1.091
PF-06372865Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2 3 and 4Change at week 3 (n= 62, 69, 70)-1.09 units on a scale
PF-06372865Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2 3 and 4Change at week 2 (n= 65, 70, 72)-0.98 units on a scale
NaproxenChange From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2 3 and 4Change at week 4 (n= 59, 64, 66)-1.58 units on a scale
NaproxenChange From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2 3 and 4Change at week 2 (n= 65, 70, 72)-1.17 units on a scale
NaproxenChange From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2 3 and 4Change at week 3 (n= 62, 69, 70)-1.39 units on a scale
NaproxenChange From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2 3 and 4Change at week 1 (n= 74, 74, 74)-0.70 units on a scale90% Confidence Interval 1.401
Comparison: Week 1: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-0.2, 0.36]
Comparison: Week 1: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-0.48, 0.07]
Comparison: Week 1: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [0.01, 0.56]
Comparison: Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-0.43, 0.34]
Comparison: Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-0.62, 0.15]
Comparison: Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-0.19, 0.58]
Comparison: Week 3: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-0.39, 0.45]
Comparison: Week 3: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-0.69, 0.16]
Comparison: Week 3: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-0.12, 0.71]
Comparison: Week 4: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-0.4, 0.55]
Comparison: Week 4: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-0.84, 0.11]
Comparison: Week 4: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-0.03, 0.91]
Secondary

Change From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4

This test assesses verbal learning and memory. Participants are given a list of 12 words and asked to repeat as many words as they can recall during 3 separate learning trials. The total recall score ranges from 0 (no memory) to 36 (best memory) while the delayed recall trial score ranges from 0 (no memory) to 12 (best memory); higher scores indicated greater verbal learning and recall.

Time frame: Baseline, Week 2, Week 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment. Here, n signifies participants who were evaluable at the specified time point for each arm.

ArmMeasureGroupValue (MEAN)Dispersion
PlaceboChange From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Total recall score: at Baseline (n= 74,74,74)24.47 units on a scaleStandard Deviation 5.118
PlaceboChange From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Total recall score: Change at Week 2 (n= 66,72,71)0.74 units on a scaleStandard Deviation 3.702
PlaceboChange From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Total recall score: Change at Week 4 (n= 56,66,66)1.43 units on a scaleStandard Deviation 3.637
PlaceboChange From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Delayed Recall Score: at Baseline (n= 74,74,74)8.59 units on a scaleStandard Deviation 2.415
PlaceboChange From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Delayed Recall Score:Change at Week 2 (n=66,72,71)0.18 units on a scaleStandard Deviation 2.225
PlaceboChange From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Delayed Recall Score:Change at Week 4 (n=56,65,66)0.57 units on a scaleStandard Deviation 1.925
PF-06372865Change From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Delayed Recall Score:Change at Week 4 (n=56,65,66)-0.28 units on a scaleStandard Deviation 2.197
PF-06372865Change From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Total recall score: at Baseline (n= 74,74,74)22.92 units on a scaleStandard Deviation 5.581
PF-06372865Change From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Delayed Recall Score: at Baseline (n= 74,74,74)8.31 units on a scaleStandard Deviation 2.828
PF-06372865Change From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Delayed Recall Score:Change at Week 2 (n=66,72,71)-0.57 units on a scaleStandard Deviation 2.803
PF-06372865Change From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Total recall score: Change at Week 2 (n= 66,72,71)0.57 units on a scaleStandard Deviation 3.95
PF-06372865Change From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Total recall score: Change at Week 4 (n= 56,66,66)0.68 units on a scaleStandard Deviation 3.522
NaproxenChange From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Total recall score: Change at Week 2 (n= 66,72,71)-0.30 units on a scaleStandard Deviation 4.773
NaproxenChange From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Total recall score: Change at Week 4 (n= 56,66,66)0.11 units on a scaleStandard Deviation 4.062
NaproxenChange From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Delayed Recall Score:Change at Week 4 (n=56,65,66)0.41 units on a scaleStandard Deviation 1.831
NaproxenChange From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Delayed Recall Score: at Baseline (n= 74,74,74)8.59 units on a scaleStandard Deviation 2.643
NaproxenChange From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Total recall score: at Baseline (n= 74,74,74)24.46 units on a scaleStandard Deviation 5.455
NaproxenChange From Baseline in Hopkins Verbal Learning Test-Revised (HVLT-R) at Week 2 and 4Delayed Recall Score:Change at Week 2 (n=66,72,71)-0.06 units on a scaleStandard Deviation 1.912
Comparison: Total recall score at Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate. Unplanned readings were excluded from the analysis.90% CI: [-1.52, 0.78]
Comparison: Total recall score at Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate. Unplanned readings were excluded from the analysis.90% CI: [-2.1, 0.2]
Comparison: Total recall score at Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate. Unplanned readings were excluded from the analysis.90% CI: [-0.56, 1.71]
Comparison: Total Recall score at Week 4: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate. Unplanned readings were excluded from the analysis.90% CI: [-2.06, 0.02]
Comparison: Total Recall score at Week 4: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate. Unplanned readings were excluded from the analysis.90% CI: [-2.25, -0.17]
Comparison: Total Recall score at Week 4: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate. Unplanned readings were excluded from the analysis.90% CI: [-0.82, 1.19]
Comparison: Delayed recall score at Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate. Unplanned readings were excluded from the analysis.90% CI: [-1.39, -0.15]
Comparison: Delayed recall score at Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate. Unplanned readings were excluded from the analysis.90% CI: [-0.8, 0.45]
Comparison: Delayed recall score at Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate. Unplanned readings were excluded from the analysis.90% CI: [-1.21, 0.02]
Comparison: Delayed recall score at Week 4: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate. Unplanned readings were excluded from the analysis.90% CI: [-1.42, -0.28]
Comparison: Delayed recall score at Week 4: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate. Unplanned readings were excluded from the analysis.90% CI: [-0.67, 0.46]
Comparison: Delayed recall score at Week 4: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate. Unplanned readings were excluded from the analysis.90% CI: [-1.29, -0.2]
Secondary

Change From Baseline in Participant's Global Assessment (PtGA) of Low Back Pain Score at Week 1, 2, 3 and 4

Participant rated 5-point Likert scale ranging from 0 (no pain) to 4 (worst possible pain) with a higher score indicating greater level of pain.

Time frame: Baseline, Week 1, 2, 3, 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment. Here, n signifies participants who were evaluable at the specified time point for each arm.

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)
PlaceboChange From Baseline in Participant's Global Assessment (PtGA) of Low Back Pain Score at Week 1, 2, 3 and 4Change at Week 1 (n= 73, 73, 73)-0.20 units on a scale
PlaceboChange From Baseline in Participant's Global Assessment (PtGA) of Low Back Pain Score at Week 1, 2, 3 and 4Change at Week 2 (n= 66, 71, 72)-0.24 units on a scale
PlaceboChange From Baseline in Participant's Global Assessment (PtGA) of Low Back Pain Score at Week 1, 2, 3 and 4Change at Week 3 (n= 62, 67, 71)-0.45 units on a scale
PlaceboChange From Baseline in Participant's Global Assessment (PtGA) of Low Back Pain Score at Week 1, 2, 3 and 4Change at Week 4 (n= 58, 65, 65)-0.33 units on a scale
PF-06372865Change From Baseline in Participant's Global Assessment (PtGA) of Low Back Pain Score at Week 1, 2, 3 and 4Change at Week 4 (n= 58, 65, 65)-0.21 units on a scale
PF-06372865Change From Baseline in Participant's Global Assessment (PtGA) of Low Back Pain Score at Week 1, 2, 3 and 4Change at Week 1 (n= 73, 73, 73)-0.19 units on a scale
PF-06372865Change From Baseline in Participant's Global Assessment (PtGA) of Low Back Pain Score at Week 1, 2, 3 and 4Change at Week 3 (n= 62, 67, 71)-0.31 units on a scale
PF-06372865Change From Baseline in Participant's Global Assessment (PtGA) of Low Back Pain Score at Week 1, 2, 3 and 4Change at Week 2 (n= 66, 71, 72)-0.28 units on a scale
NaproxenChange From Baseline in Participant's Global Assessment (PtGA) of Low Back Pain Score at Week 1, 2, 3 and 4Change at Week 4 (n= 58, 65, 65)-0.54 units on a scale
NaproxenChange From Baseline in Participant's Global Assessment (PtGA) of Low Back Pain Score at Week 1, 2, 3 and 4Change at Week 2 (n= 66, 71, 72)-0.39 units on a scale
NaproxenChange From Baseline in Participant's Global Assessment (PtGA) of Low Back Pain Score at Week 1, 2, 3 and 4Change at Week 3 (n= 62, 67, 71)-0.43 units on a scale
NaproxenChange From Baseline in Participant's Global Assessment (PtGA) of Low Back Pain Score at Week 1, 2, 3 and 4Change at Week 1 (n= 73, 73, 73)-0.34 units on a scale
Comparison: Week 1: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate.90% CI: [-0.19, 0.2]
Comparison: Week 1: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate.90% CI: [-0.34, 0.05]
Comparison: Week 1: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate.90% CI: [-0.05, 0.35]
Comparison: Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate.90% CI: [-0.26, 0.18]
Comparison: Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate.90% CI: [-0.37, 0.07]
Comparison: Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate.90% CI: [-0.1, 0.33]
Comparison: Week 3: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate.90% CI: [-0.09, 0.38]
Comparison: Week 3: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate.90% CI: [-0.21, 0.25]
Comparison: Week 3: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate.90% CI: [-0.1, 0.36]
Comparison: Week 4: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate.90% CI: [-0.13, 0.38]
Comparison: Week 4: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate.90% CI: [-0.46, 0.05]
Comparison: Week 4: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline (recordings on Day 1) was included as a covariate.90% CI: [0.08, 0.58]
Secondary

Change From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 1, 2, and 3

Each participant assessed his or her own disability due to low back pain using the RMDQ worksheet. The RMDQ total score was calculated as the total number of statements that were checked; the RMDQ total possible scores ranges from 0 to 24, with higher scores indicating greater disability.

Time frame: Baseline, Week 1, 2, 3

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment. Here, n signifies participants who were evaluable at the specified time point for each arm.

ArmMeasureGroupValue (MEAN)Dispersion
PlaceboChange From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 1, 2, and 3Baseline (n= 74, 74, 74)9.8 units on a scaleStandard Deviation 5.47
PlaceboChange From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 1, 2, and 3Change at week 1 (n= 73, 73, 73)-0.4 units on a scaleStandard Deviation 2.48
PlaceboChange From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 1, 2, and 3Change at week 2 (n= 66, 71, 72)-0.7 units on a scaleStandard Deviation 3.17
PlaceboChange From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 1, 2, and 3Change at week 3 (n= 62, 67, 71)-1.0 units on a scaleStandard Deviation 3.24
PF-06372865Change From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 1, 2, and 3Change at week 3 (n= 62, 67, 71)-1.3 units on a scaleStandard Deviation 3.39
PF-06372865Change From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 1, 2, and 3Baseline (n= 74, 74, 74)9.4 units on a scaleStandard Deviation 5.23
PF-06372865Change From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 1, 2, and 3Change at week 2 (n= 66, 71, 72)-1.3 units on a scaleStandard Deviation 3.59
PF-06372865Change From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 1, 2, and 3Change at week 1 (n= 73, 73, 73)-0.5 units on a scaleStandard Deviation 3.73
NaproxenChange From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 1, 2, and 3Change at week 3 (n= 62, 67, 71)-2.0 units on a scaleStandard Deviation 4.21
NaproxenChange From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 1, 2, and 3Change at week 1 (n= 73, 73, 73)-1.2 units on a scaleStandard Deviation 3.51
NaproxenChange From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 1, 2, and 3Change at week 2 (n= 66, 71, 72)-1.6 units on a scaleStandard Deviation 4.07
NaproxenChange From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 1, 2, and 3Baseline (n= 74, 74, 74)8.5 units on a scaleStandard Deviation 5.48
Comparison: Week 1: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-1.06, 0.7]
Comparison: Week 1: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-1.8, -0.03]
Comparison: Week 1: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-0.15, 1.61]
Comparison: Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-1.69, 0.29]
Comparison: Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-2.11, -0.11]
Comparison: Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-0.57, 1.39]
Comparison: Week 3: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-1.42, 0.6]
Comparison: Week 3: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-2.28, -0.27]
Comparison: Week 3: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect. Baseline was included as a covariate.90% CI: [-0.12, 1.85]
Secondary

Change From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 4

Each participant assessed his or her own disability due to low back pain using the RMDQ worksheet. The RMDQ total score was calculated as the total number of statements that were checked; the RMDQ total possible scores ranges from 0 to 24, with higher scores indicating greater disability.

Time frame: Baseline, Week 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment.

ArmMeasureValue (MEAN)Dispersion
PlaceboChange From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 4-1.00 units on a scale90% Confidence Interval 3.36
PF-06372865Change From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 4-1.64 units on a scale90% Confidence Interval 3.85
NaproxenChange From Baseline in Roland-Morris Disability Questionnaire (RMDQ) Total Score at Week 4-2.43 units on a scale90% Confidence Interval 4.73
Comparison: Week 4: An ANCOVA model within an outlier robust Bayesian framework was applied. Baseline was included as a fixed effect. An informative N (-3.28, 1.19\^2) prior for the placebo effect was assumed. Non informative prior distributions were assumed for the rest of the model parameters. LOCF was used for missing data.90% CI: [-1.63, 0.35]
Comparison: Week 4: An ANCOVA model within an outlier robust Bayesian framework was applied. Baseline was included as a fixed effect. An informative N (-3.28, 1.19\^2) prior for the placebo effect was assumed. Non informative prior distributions were assumed for the rest of the model parameters. LOCF was used for missing data.90% CI: [-2.4, -0.45]
Comparison: Week 4: An ANCOVA model within an outlier robust Bayesian framework was applied. Baseline was included as a fixed effect. An informative N (-3.28, 1.19\^2) prior for the placebo effect was assumed. Non informative prior distributions were assumed for the rest of the model parameters. LOCF was used for missing data.90% CI: [-0.22, 1.8]
Secondary

Chronic Low Back Pain (CLBP) Responder Index Analysis

Participants were successful responders if they had any of the following: \>=30 percent reduction in mean daily average LBPI from baseline to particular week; decrease of \>=30 percent in participant's global assessment of low back pain (disease activity) from baseline to particular week or no worsening (increase) in RMDQ total score from baseline to particular week.

Time frame: Week 1, 2, 3, 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment.

ArmMeasureGroupValue (NUMBER)Dispersion
PlaceboChronic Low Back Pain (CLBP) Responder Index AnalysisWeek 10 participants 2.62
PlaceboChronic Low Back Pain (CLBP) Responder Index AnalysisWeek 25 participants 2.65
PlaceboChronic Low Back Pain (CLBP) Responder Index AnalysisWeek 312 participants 3.11
PlaceboChronic Low Back Pain (CLBP) Responder Index AnalysisWeek 49 participants 2.37
PF-06372865Chronic Low Back Pain (CLBP) Responder Index AnalysisWeek 411 participants 2.15
PF-06372865Chronic Low Back Pain (CLBP) Responder Index AnalysisWeek 10 participants 2.49
PF-06372865Chronic Low Back Pain (CLBP) Responder Index AnalysisWeek 38 participants 2.22
PF-06372865Chronic Low Back Pain (CLBP) Responder Index AnalysisWeek 28 participants 2.77
NaproxenChronic Low Back Pain (CLBP) Responder Index AnalysisWeek 419 participants 2.45
NaproxenChronic Low Back Pain (CLBP) Responder Index AnalysisWeek 211 participants 2.54
NaproxenChronic Low Back Pain (CLBP) Responder Index AnalysisWeek 314 participants 2.46
NaproxenChronic Low Back Pain (CLBP) Responder Index AnalysisWeek 18 participants 2.44
Comparison: A repeated measures logistic regression model included treatment and week as fixed effects and LBPI baseline as a covariate. Participant was included as a repeated effect.90% CI: [0.61, 1.58]
Comparison: A repeated measures logistic regression model included treatment and week as fixed effects and LBPI baseline as a covariate. Participant was included as a repeated effect.90% CI: [1.33, 3.14]
Comparison: A repeated measures logistic regression model included treatment and week as fixed effects and LBPI baseline as a covariate. Participant was included as a repeated effect.90% CI: [0.31, 0.74]
Secondary

Number of Days Participants Used the Rescue Medication

The number of days for which the participants used the rescue medication were reported. Participants recorded the usage of acetaminophen rescue medication in the daily diary.

Time frame: Week 1, 2, 3, 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment. Here, n signifies participants who were evaluable at the specified time point for each arm.

ArmMeasureGroupValue (MEAN)Dispersion
PlaceboNumber of Days Participants Used the Rescue MedicationWeek 1 (n= 74, 74, 74)1.7 daysStandard Deviation 2.62
PlaceboNumber of Days Participants Used the Rescue MedicationWeek 2 (n= 67, 72, 72)1.6 daysStandard Deviation 2.65
PlaceboNumber of Days Participants Used the Rescue MedicationWeek 3 (n= 63, 69, 71)1.9 daysStandard Deviation 3.11
PlaceboNumber of Days Participants Used the Rescue MedicationWeek 4 (59, 66, 67)1.4 daysStandard Deviation 2.37
PF-06372865Number of Days Participants Used the Rescue MedicationWeek 4 (59, 66, 67)1.4 daysStandard Deviation 2.15
PF-06372865Number of Days Participants Used the Rescue MedicationWeek 1 (n= 74, 74, 74)1.7 daysStandard Deviation 2.49
PF-06372865Number of Days Participants Used the Rescue MedicationWeek 3 (n= 63, 69, 71)1.4 daysStandard Deviation 2.22
PF-06372865Number of Days Participants Used the Rescue MedicationWeek 2 (n= 67, 72, 72)1.8 daysStandard Deviation 2.77
NaproxenNumber of Days Participants Used the Rescue MedicationWeek 4 (59, 66, 67)1.4 daysStandard Deviation 2.45
NaproxenNumber of Days Participants Used the Rescue MedicationWeek 2 (n= 67, 72, 72)1.6 daysStandard Deviation 2.54
NaproxenNumber of Days Participants Used the Rescue MedicationWeek 3 (n= 63, 69, 71)1.5 daysStandard Deviation 2.46
NaproxenNumber of Days Participants Used the Rescue MedicationWeek 1 (n= 74, 74, 74)1.7 daysStandard Deviation 2.44
Secondary

Number of Participants Using Rescue Medication

Participants were permitted to use any commercial product (tablet/caplet/capsule) of acetaminophen (paracetamol) 500 mg as a rescue medication. Number of participants who used rescue medication were reported.

Time frame: Week 1, 2, 3, 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment. Here, n signifies participants who were evaluable at the specified time point for each arm.

ArmMeasureGroupValue (NUMBER)Dispersion
PlaceboNumber of Participants Using Rescue MedicationWeek 1 (n= 74, 74, 74)34 participants 1.351
PlaceboNumber of Participants Using Rescue MedicationWeek 2 (n= 67, 72, 72)26 participants
PlaceboNumber of Participants Using Rescue MedicationWeek 3 (n= 63, 69, 71)25 participants
PlaceboNumber of Participants Using Rescue MedicationWeek 4 (59, 66, 67)23 participants
PF-06372865Number of Participants Using Rescue MedicationWeek 4 (59, 66, 67)27 participants
PF-06372865Number of Participants Using Rescue MedicationWeek 1 (n= 74, 74, 74)35 participants 1.091
PF-06372865Number of Participants Using Rescue MedicationWeek 3 (n= 63, 69, 71)31 participants
PF-06372865Number of Participants Using Rescue MedicationWeek 2 (n= 67, 72, 72)32 participants
NaproxenNumber of Participants Using Rescue MedicationWeek 4 (59, 66, 67)22 participants
NaproxenNumber of Participants Using Rescue MedicationWeek 2 (n= 67, 72, 72)30 participants
NaproxenNumber of Participants Using Rescue MedicationWeek 3 (n= 63, 69, 71)27 participants
NaproxenNumber of Participants Using Rescue MedicationWeek 1 (n= 74, 74, 74)34 participants 1.401
Secondary

Number of Participants Withdrawn Due to Lack of Efficacy

Participants withdrew from the study due to lack of efficacy (insufficient clinical response) were reported.

Time frame: Baseline up to Week 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment.

ArmMeasureValue (NUMBER)Dispersion
PlaceboNumber of Participants Withdrawn Due to Lack of Efficacy2 participants 1.351
PF-06372865Number of Participants Withdrawn Due to Lack of Efficacy0 participants 1.091
NaproxenNumber of Participants Withdrawn Due to Lack of Efficacy1 participants 1.401
Secondary

Number of Participants With Global Evaluation of Study Medication (GESM) at Week 4

Participants rated their study treatment by GESM questionnaire. It was a qualitative measure of efficacy utilizing a 4-point Likert scale ranging from 1 (poor) to 4 (excellent), where higher score indicated a better overall response to the treatment. Number of participants who reported a particular score had been reported.

Time frame: Week 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment. Here, number of participants analyzed signifies those participants who were evaluable for this outcome measure.

ArmMeasureGroupValue (NUMBER)Dispersion
PlaceboNumber of Participants With Global Evaluation of Study Medication (GESM) at Week 4Poor8 participants 2.62
PlaceboNumber of Participants With Global Evaluation of Study Medication (GESM) at Week 4Fair26 participants 2.65
PlaceboNumber of Participants With Global Evaluation of Study Medication (GESM) at Week 4Good28 participants 3.11
PlaceboNumber of Participants With Global Evaluation of Study Medication (GESM) at Week 4Excellent8 participants 2.37
PF-06372865Number of Participants With Global Evaluation of Study Medication (GESM) at Week 4Excellent8 participants 2.15
PF-06372865Number of Participants With Global Evaluation of Study Medication (GESM) at Week 4Poor11 participants 2.49
PF-06372865Number of Participants With Global Evaluation of Study Medication (GESM) at Week 4Good36 participants 2.22
PF-06372865Number of Participants With Global Evaluation of Study Medication (GESM) at Week 4Fair18 participants 2.77
NaproxenNumber of Participants With Global Evaluation of Study Medication (GESM) at Week 4Excellent15 participants 2.45
NaproxenNumber of Participants With Global Evaluation of Study Medication (GESM) at Week 4Fair14 participants 2.54
NaproxenNumber of Participants With Global Evaluation of Study Medication (GESM) at Week 4Good37 participants 2.46
NaproxenNumber of Participants With Global Evaluation of Study Medication (GESM) at Week 4Poor5 participants 2.44
Comparison: Odds Ratios were based on a logistic regression model and included treatment as a fixed effect.90% CI: [0.46, 1.56]
Comparison: Odds Ratios were based on a logistic regression model and included treatment as a fixed effect.90% CI: [0.23, 0.81]
Comparison: Odds Ratios were based on a logistic regression model and included treatment as a fixed effect.90% CI: [1.06, 3.65]
Secondary

Number of Participants With Sustained Response Rates in Daily Average LBPI NRS Scores at Greater Than or Equal to (>=) 30 Percent and >=50 Percent Reduction From Baseline

Average back pain was assessed with an 11-point NRS ranging from 0 (no pain) to 10 (worst possible pain), where higher scores indicated higher pain. Participants described their average low back pain during the past 24 hours by choosing the appropriate number from 0 to 10. Percentage of reduction from baseline in the daily average LBPI NRS score was calculated as: (\[daily value - baseline value\] divided by baseline value) multiplied by 100. Number of participants with sustained response rates (for a minimum of 4 consecutive days) in the daily average LBPI NRS scores that were at \>=30 percent and \>=50 percent reduced from baseline were reported.

Time frame: Baseline up to Week 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment.

ArmMeasureGroupValue (NUMBER)Dispersion
PlaceboNumber of Participants With Sustained Response Rates in Daily Average LBPI NRS Scores at Greater Than or Equal to (>=) 30 Percent and >=50 Percent Reduction From Baseline>=30 percent response25 participants 1.351
PlaceboNumber of Participants With Sustained Response Rates in Daily Average LBPI NRS Scores at Greater Than or Equal to (>=) 30 Percent and >=50 Percent Reduction From Baseline>=50 percent response11 participants
PF-06372865Number of Participants With Sustained Response Rates in Daily Average LBPI NRS Scores at Greater Than or Equal to (>=) 30 Percent and >=50 Percent Reduction From Baseline>=30 percent response24 participants 1.091
PF-06372865Number of Participants With Sustained Response Rates in Daily Average LBPI NRS Scores at Greater Than or Equal to (>=) 30 Percent and >=50 Percent Reduction From Baseline>=50 percent response9 participants
NaproxenNumber of Participants With Sustained Response Rates in Daily Average LBPI NRS Scores at Greater Than or Equal to (>=) 30 Percent and >=50 Percent Reduction From Baseline>=30 percent response31 participants 1.401
NaproxenNumber of Participants With Sustained Response Rates in Daily Average LBPI NRS Scores at Greater Than or Equal to (>=) 30 Percent and >=50 Percent Reduction From Baseline>=50 percent response12 participants
Comparison: \>=30 percent sustained response rates: Odds Ratios based on a logistic regression model included treatment as a fixed effect and baseline as a covariate.90% CI: [0.54, 1.73]
Comparison: \>=30 percent sustained response rates: Odds Ratios based on a logistic regression model included treatment as a fixed effect and baseline as a covariate.90% CI: [0.81, 2.51]
Comparison: \>=30 percent sustained response rates: Odds Ratios based on a logistic regression model included treatment as a fixed effect and baseline as a covariate.90% CI: [0.39, 1.2]
Comparison: \>=50 percent sustained response rates: Odds Ratios based on a logistic regression model included treatment as a fixed effect and baseline as a covariate.90% CI: [0.37, 1.81]
Comparison: \>=50 percent sustained response rates: Odds Ratios based on a logistic regression model included treatment as a fixed effect and baseline as a covariate.90% CI: [0.53, 2.35]
Comparison: \>=50 percent sustained response rates: Odds Ratios based on a logistic regression model included treatment as a fixed effect and baseline as a covariate.90% CI: [0.33, 1.6]
Secondary

Patient Global Impression of Change (PGI-C) Score

PGI-C was a participant rated instrument to measure participant's assessment of change in his or her overall status since the previous visit on a 7-point scale; ranging from 1 (very much improved) to 7 (very much worse), where higher scores indicated more worsening.

Time frame: Week 1, 2, 3, 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment. Here, n signifies participants who were evaluable at the specified time point for each arm.

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)
PlaceboPatient Global Impression of Change (PGI-C) ScoreWeek 1 (n= 73, 73, 73)3.32 units on a scale
PlaceboPatient Global Impression of Change (PGI-C) ScoreWeek 2 (n= 66, 71, 72)3.12 units on a scale
PlaceboPatient Global Impression of Change (PGI-C) ScoreWeek 3 (n= 62, 67, 71)3.01 units on a scale
PlaceboPatient Global Impression of Change (PGI-C) ScoreWeek 4 (n= 58, 65, 65)3.04 units on a scale
PF-06372865Patient Global Impression of Change (PGI-C) ScoreWeek 4 (n= 58, 65, 65)2.93 units on a scale
PF-06372865Patient Global Impression of Change (PGI-C) ScoreWeek 1 (n= 73, 73, 73)3.15 units on a scale
PF-06372865Patient Global Impression of Change (PGI-C) ScoreWeek 3 (n= 62, 67, 71)2.94 units on a scale
PF-06372865Patient Global Impression of Change (PGI-C) ScoreWeek 2 (n= 66, 71, 72)3.04 units on a scale
NaproxenPatient Global Impression of Change (PGI-C) ScoreWeek 4 (n= 58, 65, 65)2.61 units on a scale
NaproxenPatient Global Impression of Change (PGI-C) ScoreWeek 2 (n= 66, 71, 72)2.83 units on a scale
NaproxenPatient Global Impression of Change (PGI-C) ScoreWeek 3 (n= 62, 67, 71)2.63 units on a scale
NaproxenPatient Global Impression of Change (PGI-C) ScoreWeek 1 (n= 73, 73, 73)2.95 units on a scale
Comparison: Week 1: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect.90% CI: [-0.42, 0.08]
Comparison: Week 1: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect.90% CI: [-0.62, -0.12]
Comparison: Week 1: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect.90% CI: [-0.05, 0.45]
Comparison: Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect.90% CI: [-0.38, 0.21]
Comparison: Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect.90% CI: [-0.58, 0.01]
Comparison: Week 2: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect.90% CI: [-0.09, 0.49]
Comparison: Week 3: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect.90% CI: [-0.36, 0.21]
Comparison: Week 3: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect.90% CI: [-0.67, -0.1]
Comparison: Week 3: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect.90% CI: [0.03, 0.59]
Comparison: Week 4: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect.90% CI: [-0.42, 0.21]
Comparison: Week 4: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect.90% CI: [-0.75, -0.12]
Comparison: Week 4: The mixed effect repeated measures model was used and included treatment, week, baseline, the week \* treatment interaction, and the baseline \* week interaction as fixed effects and week repeated within each participant as a repeated effect.90% CI: [0.02, 0.63]
Secondary

Percent Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2, 3 and 4

Average back pain was assessed with an 11-point NRS ranging from 0 (no pain) to 10 (worst possible pain), where higher scores indicated higher pain. Participants described their average low back pain during the past 24 hours by choosing the appropriate number from 0 to 10.

Time frame: Baseline, Week 1, 2, 3, 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment. Here, n signifies participants who were evaluable at the specified time point for each arm.

ArmMeasureGroupValue (MEAN)Dispersion
PlaceboPercent Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2, 3 and 4Change at week 1 (n= 74, 74, 74)-7.453 percent changeStandard Deviation 18.2639
PlaceboPercent Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2, 3 and 4Change at week 2 (n= 65, 70, 72)-15.190 percent changeStandard Deviation 21.7655
PlaceboPercent Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2, 3 and 4Change at week 3 (n= 62, 69, 70)-19.100 percent changeStandard Deviation 25.5461
PlaceboPercent Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2, 3 and 4Change at week 4 (n= 59, 64, 66)-20.958 percent changeStandard Deviation 25.5848
PF-06372865Percent Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2, 3 and 4Change at week 4 (n= 59, 64, 66)-17.072 percent changeStandard Deviation 27.4016
PF-06372865Percent Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2, 3 and 4Change at week 1 (n= 74, 74, 74)-5.830 percent changeStandard Deviation 16.0979
PF-06372865Percent Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2, 3 and 4Change at week 3 (n= 62, 69, 70)-17.167 percent changeStandard Deviation 23.7288
PF-06372865Percent Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2, 3 and 4Change at week 2 (n= 65, 70, 72)-15.467 percent changeStandard Deviation 20.4505
NaproxenPercent Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2, 3 and 4Change at week 4 (n= 59, 64, 66)-23.906 percent changeStandard Deviation 28.019
NaproxenPercent Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2, 3 and 4Change at week 2 (n= 65, 70, 72)-17.682 percent changeStandard Deviation 24.3704
NaproxenPercent Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2, 3 and 4Change at week 3 (n= 62, 69, 70)-22.204 percent changeStandard Deviation 23.254
NaproxenPercent Change From Baseline in Daily Low Back Pain Intensity (LBPI) as Measured by an 11-point Numeric Rating Scale (NRS) at Week 1, 2, 3 and 4Change at week 1 (n= 74, 74, 74)-10.601 percent changeStandard Deviation 17.4139
Comparison: Week 1: The mixed effect repeated measures model includes treatment, week and the week\*treatment interaction as fixed effects, week repeated within each subject as a repeated effect and log baseline as a response. LS Mean Difference and 90 percent confidence interval was calculated from log values.90% CI: [-0.03, 0.08]
Comparison: Week 1: The mixed effect repeated measures model includes treatment, week and the week\*treatment interaction as fixed effects, week repeated within each subject as a repeated effect and log baseline as a response. LS Mean Difference and 90 percent confidence interval was calculated from log values.90% CI: [-0.09, 0.02]
Comparison: Week 1: The mixed effect repeated measures model includes treatment, week and the week\*treatment interaction as fixed effects, week repeated within each subject as a repeated effect and log baseline as a response. LS Mean Difference and 90 percent confidence interval was calculated from log values.90% CI: [0.01, 0.12]
Comparison: Week 2: The mixed effect repeated measures model includes treatment, week and the week\*treatment interaction as fixed effects, week repeated within each subject as a repeated effect and log baseline as a response. LS Mean Difference and 90 percent confidence interval was calculated from log values.90% CI: [-0.09, 0.1]
Comparison: Week 2: The mixed effect repeated measures model includes treatment, week and the week\*treatment interaction as fixed effects, week repeated within each subject as a repeated effect and log baseline as a response. LS Mean Difference and 90 percent confidence interval was calculated from log values.90% CI: [-0.15, 0.05]
Comparison: Week 2: The mixed effect repeated measures model includes treatment, week and the week\*treatment interaction as fixed effects, week repeated within each subject as a repeated effect and log baseline as a response. LS Mean Difference and 90 percent confidence interval was calculated from log values.90% CI: [-0.04, 0.15]
Comparison: Week 3: The mixed effect repeated measures model includes treatment, week and the week\*treatment interaction as fixed effects, week repeated within each subject as a repeated effect and log baseline as a response. LS Mean Difference and 90 percent confidence interval was calculated from log values.90% CI: [-0.12, 0.12]
Comparison: Week 3: The mixed effect repeated measures model includes treatment, week and the week\*treatment interaction as fixed effects, week repeated within each subject as a repeated effect and log baseline as a response. LS Mean Difference and 90 percent confidence interval was calculated from log values.90% CI: [-0.16, 0.07]
Comparison: Week 3: The mixed effect repeated measures model includes treatment, week and the week\*treatment interaction as fixed effects, week repeated within each subject as a repeated effect and log baseline as a response. LS Mean Difference and 90 percent confidence interval was calculated from log values.90% CI: [-0.07, 0.16]
Comparison: Week 4: The mixed effect repeated measures model includes treatment, week and the week\*treatment interaction as fixed effects, week repeated within each subject as a repeated effect and log baseline as a response. LS Mean Difference and 90 percent confidence interval was calculated from log values.90% CI: [-0.16, 0.14]
Comparison: Week 4: The mixed effect repeated measures model includes treatment, week and the week\*treatment interaction as fixed effects, week repeated within each subject as a repeated effect and log baseline as a response. LS Mean Difference and 90 percent confidence interval was calculated from log values.90% CI: [-0.24, 0.05]
Comparison: Week 4: The mixed effect repeated measures model includes treatment, week and the week\*treatment interaction as fixed effects, week repeated within each subject as a repeated effect and log baseline as a response. LS Mean Difference and 90 percent confidence interval was calculated from log values.90% CI: [-0.05, 0.23]
Secondary

Plasma Concentration of Naproxen

Data was calculated by setting concentration values below the LLOQ to zero. The LLOQ was \<1000 ng/mL.

Time frame: Baseline, Week 1, 2, 3, 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment. Here, n signifies participants who were evaluable at the specified time point for each arm.

ArmMeasureGroupValue (MEAN)Dispersion
PlaceboPlasma Concentration of NaproxenWeek 4 (n= 65)65650 ng/mLStandard Deviation 33419
PlaceboPlasma Concentration of NaproxenBaseline (n= 73)317.0 ng/mLStandard Deviation 1963.4
PlaceboPlasma Concentration of NaproxenWeek 1 (n= 74)68150 ng/mLStandard Deviation 35213
PlaceboPlasma Concentration of NaproxenWeek 2 (n= 72)67830 ng/mLStandard Deviation 37004
PlaceboPlasma Concentration of NaproxenWeek 3 (n= 71)67140 ng/mLStandard Deviation 38336
Secondary

Plasma Concentration of PF-06372865

Data was calculated by setting concentration values below the lower limit of quantification (LLOQ) to zero. The LLOQ was \<0.0100 nanogram per milliliter (ng/mL).

Time frame: Baseline, Week 1, 2, 3, 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment. Here, n signifies participants who were evaluable at the specified time point for each arm.

ArmMeasureGroupValue (MEAN)Dispersion
PlaceboPlasma Concentration of PF-06372865Baseline (n= 73)NA ng/mL
PlaceboPlasma Concentration of PF-06372865Week 1 (n= 74)15.57 ng/mLStandard Deviation 13.214
PlaceboPlasma Concentration of PF-06372865Week 2 (n= 72)47.51 ng/mLStandard Deviation 45.668
PlaceboPlasma Concentration of PF-06372865Week 3 (n= 71)46.65 ng/mLStandard Deviation 46.305
PlaceboPlasma Concentration of PF-06372865Week 4 (n= 65)48.24 ng/mLStandard Deviation 41.975
Secondary

Time to Withdrawal Due to Lack of Efficacy

Kaplan Meier and Cox Proportional Hazards analyses were to be used to compute the time to withdrawal due to lack of efficacy. Withdrawal due to lack of efficacy was identified from the participant summary case report form (CRF) page and where reason was identified as Insufficient Clinical Response. Time to withdrawal was calculated as Date of withdrawal - Date of Randomization.

Time frame: Baseline up to Week 4

Population: FAS included all participants randomized and who had received at least 1 dose of randomized treatment.

ArmMeasureValue (MEDIAN)Dispersion
PlaceboTime to Withdrawal Due to Lack of EfficacyNA days90% Confidence Interval 1.351
PF-06372865Time to Withdrawal Due to Lack of EfficacyNA days90% Confidence Interval 1.091
NaproxenTime to Withdrawal Due to Lack of EfficacyNA days90% Confidence Interval 1.401

Source: ClinicalTrials.gov · Data processed: Feb 24, 2026