Trial Outcomes & Findings for A Phase 3, International, Multicenter, Randomized, Double-blind, Placebo-controlled, Parallel-group Efficacy and Safety Trial of Linaclotide Administered Orally for 12 Weeks to Patients With Irritable Bowel Syndrome With Constipation (IBS-C) (NCT NCT01880424)

NCT ID: NCT01880424

Last Updated: 2016-09-27

Results Overview

A 12-week Abdominal Pain/Abdominal Discomfort Responder is a patient who meets the Abdominal Pain/Abdominal Discomfort Weekly Responder criteria (i.e., an improvement of ≥30% from baseline in either the mean abdominal pain score or mean abdominal discomfort score for that week, with neither score worsening from baseline for that week) for at least 6 out of the 12 weeks of the Treatment Period. Abdominal pain at its worst (in the last 24 hours) was assessed daily by patients on an 11-point numerical rating scale (NRS) where 0 represents no abdominal pain and 10 represents very severe abdominal pain. Abdominal discomfort (in the last 24 hours) was assessed daily by patients on an 11-point NRS where 0 represents no abdominal discomfort and 10 represents very severe abdominal discomfort.

Recruitment status

COMPLETED

Study phase

PHASE3

Target enrollment

1722 participants

Primary outcome timeframe

Baseline and Weeks 1-12 during the Treatment Period

Results posted on

2016-09-27

Participant Flow

Patient recruitment occurred over an 18-month period from July 2013 to January 2015 at 98 study centers (40 in China, 42 in the US, 10 in Australia, 5 in New Zealand, and 1 in Canada).

Patients went through a 14 to 21-day Pretreatment Period during which they provided qualifying bowel habit and symptom severity assessments and rescue medicine usage through an electronic diary (eDiary). 1722 patients provided consents with 839 qualified to join th study.

Participant milestones

Participant milestones
Measure
Linaclotide Arm
Linaclotide 290 ug capsules, oral, once daily
Placebo Arm
matching placebo capsules, oral, once daily
Overall Study
STARTED
417
422
Overall Study
COMPLETED
384
367
Overall Study
NOT COMPLETED
33
55

Reasons for withdrawal

Reasons for withdrawal
Measure
Linaclotide Arm
Linaclotide 290 ug capsules, oral, once daily
Placebo Arm
matching placebo capsules, oral, once daily
Overall Study
Adverse Event
7
6
Overall Study
Lack of Efficacy
1
4
Overall Study
Lost to Follow-up
3
2
Overall Study
Protocol Violation
11
13
Overall Study
Withdrawal by Subject
10
30
Overall Study
Other
1
0

Baseline Characteristics

A Phase 3, International, Multicenter, Randomized, Double-blind, Placebo-controlled, Parallel-group Efficacy and Safety Trial of Linaclotide Administered Orally for 12 Weeks to Patients With Irritable Bowel Syndrome With Constipation (IBS-C)

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Linaclotide Arm
n=417 Participants
Linaclotide 290 ug capsules, oral, once daily
Placebo Arm
n=422 Participants
matching placebo capsules, oral, once daily
Total
n=839 Participants
Total of all reporting groups
Age, Continuous
41.0 years
STANDARD_DEVIATION 13.1 • n=5 Participants
41.3 years
STANDARD_DEVIATION 13.5 • n=7 Participants
41.1 years
STANDARD_DEVIATION 13.3 • n=5 Participants
Age, Customized
between 18 to 65 years
400 participants
n=5 Participants
405 participants
n=7 Participants
805 participants
n=5 Participants
Age, Customized
>= 65 years
17 participants
n=5 Participants
17 participants
n=7 Participants
34 participants
n=5 Participants
Sex: Female, Male
Female
333 Participants
n=5 Participants
355 Participants
n=7 Participants
688 Participants
n=5 Participants
Sex: Female, Male
Male
84 Participants
n=5 Participants
67 Participants
n=7 Participants
151 Participants
n=5 Participants
countries
China
327 Participants
n=5 Participants
332 Participants
n=7 Participants
659 Participants
n=5 Participants
countries
Canada
3 Participants
n=5 Participants
3 Participants
n=7 Participants
6 Participants
n=5 Participants
countries
Australia
19 Participants
n=5 Participants
14 Participants
n=7 Participants
33 Participants
n=5 Participants
countries
New Zealand
4 Participants
n=5 Participants
4 Participants
n=7 Participants
8 Participants
n=5 Participants
countries
United States
64 Participants
n=5 Participants
69 Participants
n=7 Participants
133 Participants
n=5 Participants

PRIMARY outcome

Timeframe: Baseline and Weeks 1-12 during the Treatment Period

Population: Intent to Treat (ITT) Population (all 839 randomized patients). If a patient did not have an abdominal pain score or abdominal discomfort score for a particular Treatment Period week, the patient was not considered a responder for that week.

A 12-week Abdominal Pain/Abdominal Discomfort Responder is a patient who meets the Abdominal Pain/Abdominal Discomfort Weekly Responder criteria (i.e., an improvement of ≥30% from baseline in either the mean abdominal pain score or mean abdominal discomfort score for that week, with neither score worsening from baseline for that week) for at least 6 out of the 12 weeks of the Treatment Period. Abdominal pain at its worst (in the last 24 hours) was assessed daily by patients on an 11-point numerical rating scale (NRS) where 0 represents no abdominal pain and 10 represents very severe abdominal pain. Abdominal discomfort (in the last 24 hours) was assessed daily by patients on an 11-point NRS where 0 represents no abdominal discomfort and 10 represents very severe abdominal discomfort.

Outcome measures

Outcome measures
Measure
Linaclotide Arm
n=417 Participants
Linaclotide 290 ug capsules, oral, once daily
Placebo Arm
n=422 Participants
matching placebo capsules, oral, once daily
12-week Abdominal Pain/Abdominal Discomfort Weekly Responder
250 Participants
206 Participants

PRIMARY outcome

Timeframe: Baseline and Weeks 1-12 during the Treatment Period

Population: Intent to Treat (ITT) Population (all 839 randomized patients). If a patient did not have an IBS degree of relief score for a particular Treatment Period week, the patient was not considered a responder for that week.

A 12-week IBS Degree of Relief Responder is a patient who meets the IBS Degree of Relief Weekly Responder criteria (i.e., response to the degree of relief of IBS symptoms question for that week was "Considerably relieved" or "Completely relieved") for at least 6 out of the 12 weeks of the Treatment Period. Degree of relief of IBS symptoms (in the last 7 days) was assessed weekly by patients on a 7-point balanced ordinal scale where 1 = Completely relieved, 4 = Unchanged, and 7 = As bad as I can imagine.

Outcome measures

Outcome measures
Measure
Linaclotide Arm
n=417 Participants
Linaclotide 290 ug capsules, oral, once daily
Placebo Arm
n=422 Participants
matching placebo capsules, oral, once daily
12-week Irritable Bowel Syndrome (IBS) Degree of Relief Responder
132 Participants
65 Participants

SECONDARY outcome

Timeframe: Baseline and 12-week Treatment Period

Population: Intent to Treat (ITT) Population (all 839 randomized patients); analysis includes patients with analysis values at both baseline and during the Treatment Period. An observed cases approach to missing post-baseline data was applied (i.e., no imputation for missing values).

The change from baseline in 12-week CSBM frequency (i.e., average weekly CSBM frequency over the 12 weeks of the Treatment Period). A spontaneous bowel movement (SBM) is defined as a bowel movement without laxative use in the preceding 24 hours. A CSBM is defined as an SBM that is associated with a sense of complete evacuation.

Outcome measures

Outcome measures
Measure
Linaclotide Arm
n=417 Participants
Linaclotide 290 ug capsules, oral, once daily
Placebo Arm
n=422 Participants
matching placebo capsules, oral, once daily
Change From Baseline in 12-week Complete Spontaneous Bowel Movement Frequency Rate
1.94 CSBMs per Week
Standard Error 0.15
0.97 CSBMs per Week
Standard Error 0.15

SECONDARY outcome

Timeframe: Baseline and 12-week Treatment Period

Population: Intent to Treat (ITT) Population (all 839 randomized patients); analysis includes patients with analysis values at both baseline and during the Treatment Period. An observed cases approach to missing post-baseline data was applied (i.e., no imputation for missing values).

The change from baseline in 12-week SBM frequency (i.e., average weekly SBM frequency over the 12 weeks of the Treatment Period). SBM is defined as a bowel movement without laxative use in the preceding 24 hours.

Outcome measures

Outcome measures
Measure
Linaclotide Arm
n=417 Participants
Linaclotide 290 ug capsules, oral, once daily
Placebo Arm
n=422 Participants
matching placebo capsules, oral, once daily
Change From Baseline in 12-week Spontaneous Bowel Movement Frequency Rate
2.96 SBMs per Week
Standard Error 0.17
1.51 SBMs per Week
Standard Error 0.17

SECONDARY outcome

Timeframe: Baseline and 12-week Treatment Period

Population: Intent to Treat (ITT) Population (all 839 randomized patients); analysis includes patients with analysis values at both baseline and during the Treatment Period. An observed cases approach to missing post-baseline data was applied (i.e., no imputation for missing values).

The change from baseline in 12-week stool consistency (i.e., the average of the non-missing Bristol Stool Form Scale \[BSFS\] score from the SBMs occurring during the 12-week Treatment Period). Consistency of each bowel movement was assessed daily by patients using the 7-point BSFS (1=Separate hard lumps like nuts \[difficult to pass\] to 7=Watery, no solid pieces \[entirely liquid\]).

Outcome measures

Outcome measures
Measure
Linaclotide Arm
n=371 Participants
Linaclotide 290 ug capsules, oral, once daily
Placebo Arm
n=360 Participants
matching placebo capsules, oral, once daily
Change From Baseline in 12-week Stool Consistency
1.51 Units on a Scale (BSFS)
Standard Error 0.07
0.82 Units on a Scale (BSFS)
Standard Error 0.07

SECONDARY outcome

Timeframe: Baseline and 12-week Treatment Period

Population: Intent to Treat (ITT) Population (all 839 randomized patients); analysis includes patients with analysis values at both baseline and during the Treatment Period. An observed cases approach to missing post-baseline data was applied (i.e., no imputation for missing values).

The change from baseline in 12-week severity of straining (i.e., the average of the non-missing straining scores from the SBMs occurring during the 12-week Treatment Period). Severity of straining was assessed daily by patients on a 5-point ordinal scale (1=Not at all to 5=An extreme amount).

Outcome measures

Outcome measures
Measure
Linaclotide Arm
n=371 Participants
Linaclotide 290 ug capsules, oral, once daily
Placebo Arm
n=360 Participants
matching placebo capsules, oral, once daily
Change From Baseline in 12-week Severity of Straining
-1.02 Units on a Scale
Standard Error 0.05
-0.69 Units on a Scale
Standard Error 0.05

SECONDARY outcome

Timeframe: Baseline and 12-week Treatment Period

Population: Intent to Treat (ITT) Population (all 839 randomized patients); analysis includes patients with analysis values at both baseline and during the Treatment Period. An observed cases approach to missing post-baseline data was applied (i.e., no imputation for missing values).

The change from baseline in 12-week abdominal bloating (i.e., the average of the non-missing daily abdominal bloating scores reported during the 12-week Treatment Period). Abdominal bloating (in the last 24 hours) was assessed daily by patients on an 11-point NRS where 0 represents no abdominal bloating and 10 represents very severe abdominal bloating.

Outcome measures

Outcome measures
Measure
Linaclotide Arm
n=417 Participants
Linaclotide 290 ug capsules, oral, once daily
Placebo Arm
n=419 Participants
matching placebo capsules, oral, once daily
Change From Baseline in 12-week Abdominal Bloating
-1.50 Units on a Scale
Standard Error 0.12
-0.94 Units on a Scale
Standard Error 0.12

SECONDARY outcome

Timeframe: Baseline and 12-week Treatment Period

Population: Intent to Treat (ITT) Population (all 839 randomized patients); analysis includes patients with analysis values at both baseline and during the Treatment Period. An observed cases approach to missing post-baseline data was applied (i.e., no imputation for missing values).

The change from baseline in 12-week abdominal pain (i.e., the average of the non-missing daily abdominal pain scores reported during the 12-week Treatment Period). Abdominal pain at its worst (in the last 24 hours) was assessed daily by patients on an 11-point NRS where 0 represents no abdominal pain and 10 represents very severe abdominal pain.

Outcome measures

Outcome measures
Measure
Linaclotide Arm
n=417 Participants
Linaclotide 290 ug capsules, oral, once daily
Placebo Arm
n=419 Participants
matching placebo capsules, oral, once daily
Change From Baseline in 12-week Abdominal Pain
-1.56 Units on a Scale
Standard Error 0.12
-1.07 Units on a Scale
Standard Error 0.12

SECONDARY outcome

Timeframe: Baseline and 12-week Treatment Period

Population: Intent to Treat (ITT) Population (all 839 randomized patients); analysis includes patients with analysis values at both baseline and during the Treatment Period. An observed cases approach to missing post-baseline data was applied (i.e., no imputation for missing values).

The change from baseline in 12-week abdominal discomfort (i.e., the average of the non-missing daily abdominal discomfort scores reported during the 12-week Treatment Period). Abdominal discomfort (in the last 24 hours) was assessed daily by patients on an 11-point NRS where 0 represents no abdominal discomfort and 10 represents very severe abdominal discomfort.

Outcome measures

Outcome measures
Measure
Linaclotide Arm
n=417 Participants
Linaclotide 290 ug capsules, oral, once daily
Placebo Arm
n=419 Participants
matching placebo capsules, oral, once daily
Change From Baseline in 12-week Abdominal Discomfort
-1.46 Units on a Scale
Standard Error 0.12
-0.98 Units on a Scale
Standard Error 0.12

Adverse Events

Linaclotide Arm

Serious events: 4 serious events
Other events: 56 other events
Deaths: 0 deaths

Placebo Arm

Serious events: 10 serious events
Other events: 26 other events
Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure
Linaclotide Arm
n=416 participants at risk
Linaclotide 290 ug capsules, oral, once daily
Placebo Arm
n=419 participants at risk
matching placebo capsules, oral, once daily
Gastrointestinal disorders
Colitis
0.00%
0/416 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
0.24%
1/419 • Number of events 1 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
General disorders
Non-cardiac chest pain
0.00%
0/416 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
0.24%
1/419 • Number of events 1 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
Infections and infestations
Pericoronitis
0.24%
1/416 • Number of events 1 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
0.00%
0/419 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
Neoplasms benign, malignant and unspecified (incl cysts and polyps)
Uterine leiomyoma
0.00%
0/416 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
0.24%
1/419 • Number of events 1 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
Nervous system disorders
Multiple system atrophy
0.00%
0/416 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
0.24%
1/419 • Number of events 1 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
Pregnancy, puerperium and perinatal conditions
Abortion spontaneous
0.00%
0/416 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
0.24%
1/419 • Number of events 1 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
Pregnancy, puerperium and perinatal conditions
Ectopic pregnancy
0.24%
1/416 • Number of events 1 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
0.00%
0/419 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
Renal and urinary disorders
Bladder outlet obstruction
0.00%
0/416 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
0.24%
1/419 • Number of events 1 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
Respiratory, thoracic and mediastinal disorders
Chronic obstructive pulmonary disease
0.24%
1/416 • Number of events 1 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
0.00%
0/419 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
Surgical and medical procedures
Abortion induced
0.24%
1/416 • Number of events 1 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
0.95%
4/419 • Number of events 4 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.

Other adverse events

Other adverse events
Measure
Linaclotide Arm
n=416 participants at risk
Linaclotide 290 ug capsules, oral, once daily
Placebo Arm
n=419 participants at risk
matching placebo capsules, oral, once daily
Gastrointestinal disorders
Diarrhea
9.4%
39/416 • Number of events 39 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
1.2%
5/419 • Number of events 5 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
Infections and infestations
Upper respiratory tract infection
4.3%
18/416 • Number of events 18 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.
5.0%
21/419 • Number of events 21 • Adverse event data were collected from July 2013 to May 2015 (12 weeks of safety data were collected). Includes serious adverse events that occurred on or after the date of the first dose of study drug and within 30 days of the last dose of study drug.
Of the 839 randomized patients, a total of 835 patients received at least one dose of double-blind study drug and were included in the Safety Population.

Additional Information

Peter Zeng

AstraZeneca

Phone: +86 21 6030 1867

Results disclosure agreements

  • Principal investigator is a sponsor employee All data generated in this trial will be the property of AstraZeneca and Ironwood Pharmaceuticals, Inc. An integrated clinical and statistical report will be prepared at the completion of the trial. Publication of the results by the Investigator will be subject to mutual agreement between the Investigator, AstraZeneca, and Ironwood Pharmaceuticals, Inc.
  • Publication restrictions are in place

Restriction type: OTHER