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

Number of Participants With Laboratory Abnormalities

时间窗: Baseline 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 Abnormalities

时间窗: Baseline 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 Categorical Scores on the Columbia Suicide Severity Rating Scale (C-SSRS)

时间窗: Screening, Baseline, Week 1, 2, 3, 4

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").

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

时间窗: End 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.

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

时间窗: Baseline, 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.

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

时间窗: 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 Electrocardiogram (ECG) Abnormalities

时间窗: Baseline 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).