A Study to Assess Adverse Events and Change in Symptoms With Linaclotide Versus Placebo in Pediatric Subjects, Ages 2 to 5 Years, With Functional Constipation

Change From Baseline in 12-week Spontaneous Bowel Movement (SBM) Frequency Rate (SBMs/Week) Observed by the Primary Caregiver During the Double-blind Study Intervention Period

Time frame · Baseline to Week 12

An SBM is defined as a BM that occurs in the absence of laxative, enema, or suppository use on the calendar day of the BM or the calendar day before the BM. The caregiver/parent/guardian/legally authorized representative (LAR) will complete the electronic diary (eDiary), providing data for the SBM frequency rate up to the last dose date equivalent to the 12-week SBM frequency rate. Baseline values for efficacy endpoints related to daily eDiary responses were derived from the eDiary in the preintervention period, specifically the time period from 14 days before randomization and up to the time of randomization.

Number of Participants With Treatment-Emergent Adverse Events

Time frame · From the time of study drug administration until 30 days or 5 half-lives after the last dose, up to 126 days in Period 1 and 226 days in Period 2

An adverse event (AE) is defined as any untoward medical occurrence in a patient/clinical investigation subject administered a pharmaceutical product which doesn't necessarily have a causal relationship with this treatment. The investigator assesses the relationship of each event to the use of study drug. A serious adverse event (SAE) is an event that results in death, is life-threatening, requires or prolongs hospitalization, results in a congenital anomaly, persistent or significant disability/incapacity or is an important medical event that, based on medical judgment, may jeopardize the subject and may require medical or surgical intervention to prevent any of the outcomes listed above. Treatment-emergent adverse events/treatment-emergent serious adverse events (TEAEs/TESAEs) are defined as any event that began or worsened in severity on or after the first dose of study drug.

Change From Baseline in 12-week Stool Consistency Observed by the Primary Caregiver During the Double-blind Study Intervention Period

Time frame · Baseline to Week 12

The caregiver/parent/guardian/legally authorized representative (LAR) rated and recorded in an eDiary the consistency of the stool for each BM using the Bristol Stool Form 7-point scale in which 1=Separate hard lumps, like nuts (hard to pass); 2=Sausage-shaped, but lumpy; 3=Like a sausage but with cracks on its surface; 4=Like a sausage or snake, smooth and soft; 5=Soft blobs with clear cut edges (easy to pass); 6=Fluffy pieces with ragged edges, a mushy stool; and 7=Watery, no solid pieces, entirely liquid. A response of "I don't know" was considered as a missing score. Lower scores indicate firmer stool consistency. A subject's stool consistency score for the study intervention period is the average of the non-missing BSFS scores for the primary caregiver-observed SBMs during that specific period.

Change From Baseline in 12-week Straining Observed by the Primary Caregiver During the Double-blind Study Intervention Period

Time frame · Baseline to Week 12

The caregiver/parent/guardian/LAR rated and recorded in an eDiary the amount of straining they observed when the child passed the BM using two 3-point rating scales:. 1) For the bowel movement #X you were with the child for, did he/she grunt like he/she was straining? 0 = No, not at all; 1 = Yes, a little; 2 = Yes, a lot; I don't know. 2) For the bowel movement #X you were with the child for, did he/she make a face like he/she was straining? 0 = No, not at all; 1 = Yes, a little; 2 = Yes, a lot; I don't know. "I don't know" was considered a missing response. Higher scores indicate more straining. The subject's straining score was the average of the nonmissing average straining scores for all the primary caregiver-observed SBMs during the specific period.

Change From Baseline in 12-week Proportion of Days With Fecal Incontinence During the Double-blind Study Intervention Period (for Those With Toileting Skills)

Time frame · Baseline to Week 12

Caregivers of children who have acquired toileting skills for BMs were asked about their child's fecal incontinence episodes. Toileting skills were assessed as part of the first daily diary, modified daily diary, or clinic diary and responses were carried through to the completion of the study.