The study listed may include approved and non-approved uses, formulations, or treatment regimens. The results
reported in any single study may not reflect the overall results obtained on studies of a product. Before
prescribing any product mentioned in this registry, healthcare professionals should consult prescribing
information for the product approved in their country.
Results presented here may include different data from those shown on http:clinicaltrials.gov/, which specifically
identifies data to be disclosed, as mandated by US federal law.
Title of Study: A Randomized, Placebo-Controlled, Double-Blind, Trial of Polyethylene Glycol 3350
Laxative for the Treatment of Occasional Constipation
Studied Period: First subject enrolled: November 28, 2007 Clinical Phase: 4
Last subject last visit: January 18, 2008
Objective(s): The primary objective of this study was to evaluate the resolution of straining and lumpy or
hard stools in subjects taking PEG 3350 as compared to Placebo based on analysis of self-reported bowel
movement (BM) data. Secondary objectives, measured by analysis of a subject questionnaire and self-reported
BM data, included comparisons of PEG 3350 to Placebo for the number of bowel movements, the time to first
bowel movement, bowel movement control, gas, bloating, abdominal discomfort/cramping, changes in straining
and hard or lumpy stools, bowel movement satisfaction, quality of life, and the overall efficacy and preference for
study medication versus the subject’s usual laxative.
Methodology: This was a multi-center, randomized, Placebo-controlled, double-blind study, with the maximum
length of double-blind treatment being up to 7 days. There were two visits in this study, and each subject’s
participation lasted up to 13 days.
Number of Subjects: Twenty-nine percent of the subjects in this study were male and Seventy-one percent
were female. They ranged in age from 17 to 79 years with 74.9 percent were white, 16.3% were Latino, 7.9%
were Black/African-American and 1% American Indian. The subjects were found to be comparable in the two
groups with respect to their medical histories, baseline physical examinations and general habitus including
height and weight. Subjects were also equivalent in terms of vital signs. The two treatment groups in the study
were fully comparable in terms of their baseline characteristics.
Diagnosis and Criteria for Inclusion: This study enrolled subjects 17 years or older with occasional
constipation who presented with a current diagnosis of untreated constipation for 7 days or less based on having
signs/symptoms of straining and hard or lumpy stools OR the inability to have a BM within 48 hours prior to
randomization into the trial. To meet protocol requirements, subjects were required to undergo a brief physical
examination and a constipation history that included confirmation of signs of constipation. Subjects with
significant medical conditions and history of significant ongoing problems outlined in the exclusion criteria were
not enrolled in the study. Subjects taking medications that are considered to cause constipation, medications
which treat constipation, or medications with known laxative properties were excluded from the study. Pregnant
or nursing subjects were also excluded.
Test Product, Dose, Mode of Administration: MiraLAX® (polyethylene glycol [PEG] 3350 powder for
solution)/ 17g MALTRIN® M500 (maltodextrin 500).
Duration of Treatment: All subjects in this study had a maximum length of double-blind treatment for up to 7
days. Each subject’s participation was approximately up to 13 days. The study was comprised of a
screening/baseline evaluation which included randomization if the subject qualified (Visit 1), a 7-day at home
double-blind treatment period, and an end of study visit (Visit 2).
Reference Therapy, Dose, Mode of Administration: Placebo
Criteria for Evaluation:
Efficacy: In this study, subjects rated their constipation symptoms in their subject diary at the time of each
complete, incomplete, and attempted BM. Every morning prior to noon when study medication was taken,
subjects would indicate how bothersome constipation had been to them in the prior 24 hours using the Visual
Analog Scale (VAS). The primary efficacy outcome variable, the proportion of subjects who report complete
resolution of straining and hard/lumpy stools, was performed for the intent-to-treat (ITT) (that is, the population
including all randomized subjects that were dispensed study medication) and the per-protocol population. The
secondary endpoints, included diary ratings in VAS format (BM control, gas, bloating, abdominal
discomfort/cramping, well-being) and binary format including Likert rating outcomes (BM satisfaction, BM sense
of completion, Preferred laxative as well as QOL outcomes).
Safety: The assessment of safety was based on the tabulation and analysis of adverse events as well as the
measurement of vital signs at Visit 1.
Statistical Methods: All primary statistical tests were conducted using an intent-to-treat population. The
primary statistical tests were also performed on a per protocol population to assess the robustness of the results.
The primary analysis variable was the relief of straining and hard/lumpy stools over the entire 7-day treatment
period. This was analyzed using Cochran-Mantel-Haenszel (CMH) analysis which compared the two groups on
a binary response, adjusting for investigational site.
Secondary analyses utilized the same CMH analysis for all binary outcomes in a comparison between the
treatment groups and all VAS or Likert ratings were compared between treatment groups using analysis of
variance with factors for treatment, site, and treatment-site interaction. These endpoints consisted of the
following analyses: diary ratings in VAS format (BM control, gas, bloating, abdominal discomfort/cramping, well-
being) and binary format including Likert rating outcomes (BM satisfaction, BM sense of completion, Preferred
laxative as well as QOL outcomes). The binary ratings which were reported for each stool were averaged over
all stools before analysis, giving a single variable per subject. The VAS rating scales were be assessed as
percent change from baseline over time, and where applicable, were also averaged over all stools before
analysis, giving a single variable per subject. The number of bowel movements reported in the 7-day period and
the time to first bowel movement (from time of first study medication to time of first bowel movement, reported in
hours) were compared between treatment groups using CMH row mean scores statistics. The QOL
questionnaires were analyzed with CMH row mean scores statistics by using the change from baseline in the
total sum score to compare treatment groups. Preference questionnaires, which were also presented as binary
outcomes, were analyzed using analysis of variance and CMH statistics, similarly to the diary endpoints
Primary Efficacy Results:
The primary efficacy measure evaluated the resolution of straining and lumpy or hard stools in subjects taking
PEG 3350 as compared to Placebo based on analysis of self-reported bowel movement (BM) data.
Table 220.127.116.11 Summary of Overall Assessment of Complete Response Per-Protocol
Summary PEG 3350 Placebo P-value 
Complete Resolution 
Yes 36 (36.7%) 23 (24.5%) 0.0595
No 62 (63.3%) 71 (75.5%)
: A resolution will be recorded if the subject has no occurrence of two or more consecutive unsuccessful
bowel movements for the rest of the study following the first successful bowel movement.
: P-value obtained from CMH chi-square test adjusting for pooled study site for the test that successes
were homogenous across the treatment arms.
This data indicates that PEG 3350 closely approaches statistical significance in terms of the primary efficacy
outcome measure. It reflects the subject’s own estimation that the treatment resolved their constipation
symptoms of straining and hard/lumpy stools.
Secondary Efficacy Variables:
A review of the secondary efficacy variables in this study shows the statistically significant superiority of PEG
3350 over Placebo. Two of these variables assessed the relief of straining and hard/lumpy stools over the 7-day
treatment period in terms of a reduction of severity as the subjects use the test drug every day for 7 days; as well
as the percent of all BMs that were complete without straining or lumpy stools. The data for these tables are
presented below in Table 18.104.22.168 and 22.214.171.124.
Table 126.96.36.199 Summary of Average Subject Daily Diary Bowel Movement (BM) Assessments Per-Protocol
Treatment Description n Mean (Std) Median Min, Max P-value
PEG 3350 Average BMs per day 98 1.1 (0.84) 1.0 0.1, 6.0 0.4614
Average BMs per day that were 98 0.6 (0.46) 0.6 0.0, 2.0 0.5687
complete without straining or lumpy
Percent of all BMs that were complete 98 34.0 16.7 0.0, 0.0002
without straining or lumpy stool (35.84) 100.0
Percent of all BMs that were failures 98 10.1 0.0 0.0, 85.7 0.9398
Percent of all BMs that were incomplete 98 25.7 16.7 0.0, 0.1633
Placebo Average BMs per day 94 1.0 (0.63) 0.9 0.0, 3.3
Average BMs per day that were 94 0.5 (0.46) 0.4 0.0, 2.5
complete without straining or lumpy
Percent of all BMs that were complete 94 18.4 0.0 0.0,
without straining or lumpy stool (25.00) 100.0
Percent of all BMs that were failures 94 10.2 0.0 0.0, 81.8
Percent of all BMs that were incomplete 94 34.6 33.3 0.0,
Table 188.8.131.52 Summary of Average VAS Score for Daily Diary Bowel Movement (BM) Assessments Per-
Treatment Description n Mean (Std) Median Min, Max P-value 
PEG 3350 Bloating 98 27.0 (21.97) 24.9 0.0, 97.8 0.9580
Control 98 34.3 (18.63) 33.8 2.0, 82.6 0.8019
Cramping 98 23.5 (21.63) 18.9 0.0, 91.2 0.5879
Gas 98 32.6 (23.09) 28.1 0.3, 98.5 0.9053
Hardness 98 29.0 (24.23) 24.9 0.0, 96.0 <.001
Straining 98 21.1 (22.69) 14.2 0.0, 93.2 <.001
Placebo Bloating 94 27.3 (19.44) 24.7 0.0, 77.7
Control 94 33.5 (19.00) 32.0 0.0, 76.4
Cramping 94 25.9 (20.17) 23.6 0.0, 82.0
Gas 94 31.6 (19.42) 27.1 0.0, 81.6
Hardness 94 45.3 (25.24) 45.3 0.0, 95.0
Straining 94 37.8 (24.06) 36.0 0.0, 91.3
As detailed above the average VAS scores for straining and hardness of stool shows that subjects on PEG 3350
experienced significant improvement in their straining and lumpy stool constipation symptoms (p<.0001). For the
PEG 3350 group 34% of all the BMs they experienced were complete without straining or lumpy stools. This
compares to 18.4% for the Placebo group. These results are highly significant at p<.0002.
These results of secondary efficacy variables in this study were based on the subject’s daily symptom score
sums. They illustrate that while there was no statistically significant decrease in the symptoms of constipation
(control, gas, bloating, cramping), PEG 3350 did not contribute to these symptoms. In the subjects’ comparison
of PEG 3350 to their regular laxative, PEG 3350 was considered superior in every one of these symptoms.
Safety: The adverse events observed in this study were equally balanced between the PEG 3350 and Placebo
groups demonstrating that it was not a drug related effect. There were no deaths and no serious adverse events
during the active treatment phase.
CONCLUSIONS: This study demonstrated that PEG (polyethylene glycol 3350 powder for solution) once a day
is a safe, effective and well-tolerated treatment for the symptoms of occasional constipation.
Date of the Report: 29 MAY 2009.