Placebo taken orally once every day for 15 weeks

BPI 24-hour average pain severity is a self-reported scale that measures the severity of pain based on the average pain over the past 24-hours. Severity scores ranged from 0 (no pain) to 10 (severe pain). LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between the administration groups as fixed effects, and BPI average pain severity at baseline and the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

BPI 24-hour average pain severity is a self-reported scale that measures the severity of pain based on the average pain over the past 24-hours. Severity scores ranged from 0 (no pain) to 10 (severe pain). LS mean was calculated using an analysis of covariance (ANCOVA) approach including administration groups as fixed effects, and BPI average pain severity at baseline and the presence or absence of major depressive disorder as covariates.

CGI-I measures the clinician's perception of participant improvement at the time of assessment (compared with the start of treatment). Scores ranged from 1 (very much better) to 7 (very much worse). LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between the administration groups as fixed effects, and the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

FIQ is a 20-item, self-administered questionnaire using Likert-type scales to measure participant (pt) outcomes over the past week. Items 1 through 11 measured physical functioning on 4-point scales. Items 12 and 13 measured the number of days a pt felt well and days a pt was unable to work due to fibromyalgia symptoms. Items 14 through 20 were 11-point scales on which a pt rated work difficulty, pain, fatigue, morning tiredness, stiffness, anxiety, and depression. If a pt did not do all the tasks listed, those items were deleted from scoring. Algorithms were used to determine total FIQ scores which ranged from 0 to 100; higher scores indicated a more negative impact. LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between administration groups as fixed effects, and baseline as well as the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

The SF-36 Health Survey is a generic, health-related survey assessing the participant's quality of life on 8 domains: physical functioning, daily functioning (physical), bodily pain, general health, vitality, social functioning, daily functioning (emotional), and mental health. Each domain was scored by summing individual items pertaining to that domain and transforming scores into a 0 to 100 scale, with higher scores indicating better health status or functioning. LS mean was calculated using an ANCOVA approach including administration groups as fixed effects, and baseline as well as the presence or absence of complication by major depressive disorder as covariates.

The BDI-II is a 21-item self-administered questionnaire designed to assess the characteristics of depression. Each item was scored on a 4-point scale ranging from 0 (not present) to 3 (present in the extreme) and was summed to give a total BDI-II score. A total BDI-II score of 0 through 13 was considered minimal, 14 through 19 was mild, 20 through 28 was moderate, and 29 through 63 was severe depression symptoms. LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between the administration groups and as fixed effects, and baseline as well as the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

WPI: Participant-reported areas (out of 19 points on the body) in which the participant had pain in the past week. WPI scores ranged from 0 (no areas) to 19 (all areas). SS: The sum of severity scores for fatigue, waking unrefreshed, and cognitive symptoms [each rated from 0 (no problem) to 3 (severe; life-disturbing problems)] plus the severity of somatic symptoms in general [rated from 0 (no symptoms) to 3 (a great deal of symptoms)]. The total SS score ranged from 0 and 12. LS mean was calculated using an MMRM approach including administration groups, observation points, interaction between the administration groups and the observation points as fixed effects, and baseline as well as the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

Each morning participants rated their average pain and worst pain within the past 24 hours on separate 11-point Likert scales with scores ranging from 0 (no pain) through 10 (worst possible pain). These scores were then averaged for the week and compared to baseline. LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between the administration groups as fixed effects, and baseline as well as the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

BPI-S and BPI-I are self-reported scales measuring severity of pain and interference on function, respectively. Severity scores ranged from 0 (no pain) to 10 (severe pain) for each question assessing worst pain, least pain, and pain right now. Interference scores ranged from 0 (does not interfere) to 10 (completely interferes) for each question assessing interference of pain in past 24 hours with general activity, mood, walking ability, normal work, relations with other people, sleep, and enjoyment of life. Average interference was the average of non-missing scores of individual interference items. LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between the administration groups as fixed effects, and baseline as well as the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

Treatment Period: 3 placebo capsules administered orally once daily for 14 weeks.

During the 1-week taper, the number of placebo capsules was gradually reduced. For the first 3 days: 2 placebo capsules administered orally once daily. For the remaining 4 days: 1 placebo capsule administered orally once daily.

Total of all reporting groups

Treatment Period: 3 placebo capsules administered orally once daily for 14 weeks.

PGI-I measures the participant's perception of improvement at the time of assessment compared with the start of treatment. Scores ranged from 1 (very much better) to 7 (very much worse). LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between the administration groups as fixed effects, and the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

Randomized participants who received at least 1 dose of study drug and had at least 1 post-baseline measurement of primary efficacy (BPI 24-hour average pain severity).

CGI-I measures the clinician's perception of participant improvement at the time of assessment (compared with the start of treatment). Scores ranged from 1 (very much better) to 7 (very much worse). LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between the administration groups as fixed effects, and the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

Randomized participants who received at least 1 dose of study drug and had at least 1 post-baseline measurement of primary efficacy (BPI 24-hour average pain severity).

FIQ is a 20-item, self-administered questionnaire using Likert-type scales to measure participant (pt) outcomes over the past week. Items 1 through 11 measured physical functioning on 4-point scales. Items 12 and 13 measured the number of days a pt felt well and days a pt was unable to work due to fibromyalgia symptoms. Items 14 through 20 were 11-point scales on which a pt rated work difficulty, pain, fatigue, morning tiredness, stiffness, anxiety, and depression. If a pt did not do all the tasks listed, those items were deleted from scoring. Algorithms were used to determine total FIQ scores which ranged from 0 to 100; higher scores indicated a more negative impact. LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between administration groups as fixed effects, and baseline as well as the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

Randomized participants who received at least 1 dose of study drug and had at least 1 post-baseline measurement of primary efficacy (BPI 24-hour average pain severity).

The SF-36 Health Survey is a generic, health-related survey assessing the participant's quality of life on 8 domains: physical functioning, daily functioning (physical), bodily pain, general health, vitality, social functioning, daily functioning (emotional), and mental health. Each domain was scored by summing individual items pertaining to that domain and transforming scores into a 0 to 100 scale, with higher scores indicating better health status or functioning. LS mean was calculated using an ANCOVA approach including administration groups as fixed effects, and baseline as well as the presence or absence of complication by major depressive disorder as covariates.

Randomized participants who received at least 1 dose of study drug and had at least 1 post-baseline measurement of primary efficacy (BPI 24-hour average pain severity); LOCF values were used.

The BDI-II is a 21-item self-administered questionnaire designed to assess the characteristics of depression. Each item was scored on a 4-point scale ranging from 0 (not present) to 3 (present in the extreme) and was summed to give a total BDI-II score. A total BDI-II score of 0 through 13 was considered minimal, 14 through 19 was mild, 20 through 28 was moderate, and 29 through 63 was severe depression symptoms. LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between the administration groups and as fixed effects, and baseline as well as the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

Randomized participants who received at least 1 dose of study drug and had at least 1 post-baseline measurement of primary efficacy (BPI 24-hour average pain severity).

WPI: Participant-reported areas (out of 19 points on the body) in which the participant had pain in the past week. WPI scores ranged from 0 (no areas) to 19 (all areas). SS: The sum of severity scores for fatigue, waking unrefreshed, and cognitive symptoms [each rated from 0 (no problem) to 3 (severe; life-disturbing problems)] plus the severity of somatic symptoms in general [rated from 0 (no symptoms) to 3 (a great deal of symptoms)]. The total SS score ranged from 0 and 12. LS mean was calculated using an MMRM approach including administration groups, observation points, interaction between the administration groups and the observation points as fixed effects, and baseline as well as the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

Randomized participants who received at least 1 dose of study drug and had at least 1 post-baseline measurement of primary efficacy (BPI 24-hour average pain severity).

Each morning participants rated their average pain and worst pain within the past 24 hours on separate 11-point Likert scales with scores ranging from 0 (no pain) through 10 (worst possible pain). These scores were then averaged for the week and compared to baseline. LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between the administration groups as fixed effects, and baseline as well as the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

Randomized participants who received at least 1 dose of study drug and had at least 1 post-baseline measurement of primary efficacy (BPI 24-hour average pain severity).

BPI-S and BPI-I are self-reported scales measuring severity of pain and interference on function, respectively. Severity scores ranged from 0 (no pain) to 10 (severe pain) for each question assessing worst pain, least pain, and pain right now. Interference scores ranged from 0 (does not interfere) to 10 (completely interferes) for each question assessing interference of pain in past 24 hours with general activity, mood, walking ability, normal work, relations with other people, sleep, and enjoyment of life. Average interference was the average of non-missing scores of individual interference items. LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between the administration groups as fixed effects, and baseline as well as the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

Randomized participants who received at least 1 dose of study drug and had at least 1 post-baseline measurement of primary efficacy (BPI 24-hour average pain severity).

BPI 24-hour average pain severity is a self-reported scale that measures the severity of pain based on the average pain over the past 24-hours. Severity scores ranged from 0 (no pain) to 10 (severe pain). LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between the administration groups as fixed effects, and BPI average pain severity at baseline and the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

Randomized participants who received at least 1 dose of study drug and had at least 1 post-baseline measurement of primary efficacy (BPI 24-hour average pain severity).

BPI 24-hour average pain severity is a self-reported scale that measures the severity of pain based on the average pain over the past 24-hours. Severity scores ranged from 0 (no pain) to 10 (severe pain). LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between the administration groups as fixed effects, and BPI average pain severity at baseline and the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

Randomized participants who received at least 1 dose of study drug and had at least 1 post-baseline measurement of primary efficacy (BPI 24-hour average pain severity).

BPI 24-hour average pain severity is a self-reported scale that measures the severity of pain based on the average pain over the past 24-hours. Severity scores ranged from 0 (no pain) to 10 (severe pain). LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between the administration groups as fixed effects, and BPI average pain severity at baseline and the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

Randomized participants who received at least 1 dose of study drug and had at least 1 post-baseline measurement of primary efficacy (BPI 24-hour average pain severity).

BPI 24-hour average pain severity is a self-reported scale that measures the severity of pain based on the average pain over the past 24-hours. Severity scores ranged from 0 (no pain) to 10 (severe pain). LS mean was calculated using an MMRM approach including administration groups, observation points, and interaction between the administration groups as fixed effects, and BPI average pain severity at baseline and the presence or absence of major depressive disorder as covariates; a linear model with unstructured error variance was applied.

Randomized participants who received at least 1 dose of study drug and had at least 1 post-baseline measurement of primary efficacy (BPI 24-hour average pain severity).

BPI 24-hour average pain severity is a self-reported scale that measures the severity of pain based on the average pain over the past 24-hours. Severity scores ranged from 0 (no pain) to 10 (severe pain). LS mean was calculated using an analysis of covariance (ANCOVA) approach including administration groups as fixed effects, and BPI average pain severity at baseline and the presence or absence of major depressive disorder as covariates.

Randomized participants who received at least 1 dose of study drug and had at least 1 post-baseline measurement of primary efficacy (BPI 24-hour average pain severity); Last Observation Carried Forward (LOCF) values were used.

Treatment Period: 3 placebo capsules administered orally once daily for 14 weeks.

During the 1-week taper, the number of placebo capsules was gradually reduced. For the first 3 days: 2 placebo capsules administered orally once daily. For the remaining 4 days: 1 placebo capsule administered orally once daily.