An Open Study to Evaluate Whether Pack Size Affects Compliance of Metformin Treatment in Subjects With Type II Diabetes

Phase 4

Terminated

Conditions: Diabetes Mellitus, Type 2

Interventions: Drug: Metformin Small Pack
Drug: Metformin Large Pack

Registration Number: NCT01817777

Lead Sponsor: GlaxoSmithKline

Brief Summary: MTF116086 is an open-label, randomised, parallel-design study in subjects with type II diabetes. The study is site-based, with local pharmacies serving as the sites and pharmacists as principal investigators for the sites. All subjects will enter an initial 8-week observational phase during which purchase behaviour and compliance with usual metformin use will be observed and recorded. At the end of the observational phase, subjects will be randomised to one of the two arms (metformin small pack vs. metformin large pack) for a 20-week interventional phase. The medication in the interventional phase is provided to the subjects free of charge. HbA1c will be collected for all subjects during Week 0, Week 8, and Week 28. Subjects will be asked questions about their tablet compliance, their satisfaction with the pack size they received and reasons for missing doses throughout the interventional phase by the pharmacist. The pharmacy visit on Week 28 will be end of the study.

Detailed Description: Not available

Recruitment & Eligibility

Status: TERMINATED

Sex: All

Target Recruitment: 31

Inclusion Criteria

Males and females of age >=18 years
Diagnosis of type II diabetes
HbA1c value no higher than 9.0%
Evidence of physician-supplied prescription for metformin use
Stable dose of metformin for 3 months prior to enrolment
Written informed consent from the subject

Exclusion Criteria

Current use of any anti-diabetic medication other than metformin

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Metformin Small Pack Arm	Metformin Small Pack	All subjects in the study will be initially followed for an 8-week observational phase during which subjects will visit the pharmacy and purchase metformin following their usual routines. After 8-weeks subjects will be randomised to one of the 2 treatments arms. Subjects in the metformin small pack arm will receive medication free of charge in a small pack. Dosing of metformin will not be dictated by the protocol. Subjects will remain on their prescribed dose of metformin throughout the study, unless a change is recommended by their physician.
Metformin Large Pack Arm	Metformin Large Pack	All subjects in the study will be initially followed for an 8-week observational phase during which subjects will visit the pharmacy and purchase metformin following their usual routines. After 8-weeks subjects will be randomised to one of the 2 treatments arms. Subjects in the metformin large pack arm will receive medication free of charge in a large, monthly pack. Dosing of metformin will not be dictated by the protocol. Subjects will remain on their prescribed dose of metformin throughout the study, unless a change is recommended by their physician.

Primary Outcome Measures

Name	Time	Method
Change From Baseline in HbA1c Values at Week 28	Baseline (Week 8) and Week 28	HbA1c was tested with a point-of-care device, which required a finger prick to obtain blood and provided an immediate result upon analysis in the device. HbA1c was tested at pharmacy visits corresponding to three time points: enrollment (Week 0), Baseline (Week 8), and End of Study (Week 28). The difference in the mean change from Baseline was to be calculated between the treatment arms (small pack minus large pack), and the 2-sided 95% confidence interval for the difference in mean change in HbA1c was to be calculated. However, because the study was terminated early, and the sample size was reduced, the statistical hypotheses defined in the protocol were not tested due to insufficient power. Therefore, the final analyses were limited to descriptive statistics. The percentage HbA1c is a measure of how much of the hemoglobin in the blood has become glycated (chemically bounded to glucose).

Secondary Outcome Measures

Name	Time	Method
Number of Participants Withdrawn From the Study Due to the Following Reasons: Withdrawal of Informed Consent; Lost to Follow-up	Week 28	The number of participants who voluntarily discontinued participation in the study at any time or who were withdrawn by the investigator for pre-defined reasons was summarized.
Mean Percent Compliance Throughout the Interventional Phase	From Randomization to Week 28	Compliance for the study was estimated as a percentage, with the denominator defined as the number of pills dispensed by the pharmacist and the numerator defined as the number of pills taken, accounting for remaining pills at subsequent pharmacy visits.
Mean Percent Compliance Throughout the Observational Phase, Per Treatment They Were Randomized to in the Interventional Phase	From enrollment to Week 8	Compliance was estimated during the 8-week Observational Phase for usual metformin treatment. During the Observational Phase, compliance was measured by monitoring the number of pill dispensed and the return of the pills or tablets.
Number of Participants Who Took Zero Metformin Pills for the Indicated Number of Days	Week 28	The number of days on which no metformin pills were taken by participants was summarized.
Number of Participants With Diabetes Disease Management Modifications	Week 28	Throughout the duration of the study, participants remained on their recommended metformin dosing regimens, unless a change in metformin dose was prescribed by their physician. The number of participants who received additional diabetes therapy for the management of diabetes was summarized.
Number of Participants Who Required a Non-routine Health Care Professional Visit for Diabetes	Week 28	The number of participants who visited a health care professional for diabetes management during the study was summarized.
Number of Participants Who Preferred Their Treatment Regimens (Interventional Arm Treatment [Large or Small Pack Metformin]) to How They Previously Took Their Medication	Week 28	Number of participants who preferred their treatment regimens (interventional arm treatment \[large or small pack metformin\]) to how they previously took their medication are presented.
Number of Participants Who Missed Metformin Days/Doses for the Indicated Reasons	Week 28	The number of particiapnts who missed days or doses of metformin was summarized.