Patients With Heart Failure ANd Type 2 Diabetes Treated With Placebo Or Metformin (PHANTOM) Pilot Study

Overview[ - collapse ][ - ]

Purpose To conduct a pilot study to evaluate the feasibility of a large randomized controlled trial (RCT) of metformin in patients with heart failure and type 2 diabetes and to generate initial morbidity and mortality estimates in this patient population. The primary hypothesis is that subjects with heart failure and type 2 diabetes who receive metformin will have a significant reduction in the combined endpoint of all-cause mortality and all-cause hospitalization as compared to subjects who receive placebo therapy.
ConditionDiabetes Mellitus, Type 2
Heart Failure, Congestive
InterventionDrug: Metformin
PhasePhase 3
SponsorUniversity of Alberta
Responsible PartyUniversity of Alberta
ClinicalTrials.gov IdentifierNCT00325910
First ReceivedMay 12, 2006
Last UpdatedMay 12, 2008
Last verifiedMay 2008

Tracking Information[ + expand ][ + ]

First Received DateMay 12, 2006
Last Updated DateMay 12, 2008
Start DateMay 2006
Estimated Primary Completion DateMay 2007
Current Primary Outcome MeasuresCombined endpoint of all cause mortality and all cause hospitalization at 6 months
Current Secondary Outcome Measures
  • Individual components of the primary outcome (ie death or hospitalization)
  • Change in A1c
  • Change in 6 minute walk
  • Change in Health Related Quality of Life
  • Development of Lactic Acidosis

Descriptive Information[ + expand ][ + ]

Brief TitlePatients With Heart Failure ANd Type 2 Diabetes Treated With Placebo Or Metformin (PHANTOM) Pilot Study
Official TitlePatients With Heart Failure ANd Type 2 Diabetes Treated With Placebo Or Metformin (PHANTOM) Pilot Study
Brief Summary
To conduct a pilot study to evaluate the feasibility of a large randomized controlled trial
(RCT) of metformin in patients with heart failure and type 2 diabetes and to generate
initial morbidity and mortality estimates in this patient population. The primary hypothesis
is that subjects with heart failure and type 2 diabetes who receive metformin will have a
significant reduction in the combined endpoint of all-cause mortality and all-cause
hospitalization as compared to subjects who receive placebo therapy.
Detailed Description
Background: Heart failure (HF) is a common complication of type 2 diabetes mellitus. There
are limited treatment options for patients with HF and diabetes. Although metformin is
considered a safe and effective medication, it is currently not recommended in patients who
have HF due to a perceived increased risk of lactic acidosis. There is increasing evidence
to suggest that HF does not predispose patients to increased risk of metformin induced
lactic acidosis. Moreover, recent observational research has shown that metformin may be
associated with reduced morbidity and mortality in diabetic HF patients as compared to
sulfonylurea therapy.

Study Purpose: To conduct a pilot study to evaluate the feasibility of a large randomized
controlled trial (RCT) of metformin in patients with heart failure and type 2 diabetes and
to generate initial morbidity and mortality estimates in this patient population.

Study Design: A multi-centre prospective triple blinded randomized placebo controlled trial
(RCT) design. Subjects will be recruited through specialist clinics (e.g., heart failure
clinics, diabetes clinics), inpatient hospital admissions/emergency room visits and
physician referrals in the Capital Health Region.

Subjects: All subjects with physician-diagnosed symptomatic heart failure (NYHA class I,
II, III, IV) and type 2 diabetes are eligible for the study. All subjects with the following
conditions will be excluded from the study: subjects currently receiving greater than 1500
mg of metformin therapy per day; subjects who are unwilling to change their antidiabetic
regimens; subjects receiving insulin therapy; serum creatinine ≥ 180 μmol/L; A1c < 7.0
percent; inability to communicate (language barrier); dementia/mental illness; age < 18
years; subjects unwilling to complete self monitoring of serum blood sugars during the trial
period; those participating in another heart failure or diabetes clinical trial involving
medications; severe comorbidities or foreshortened life expectancy; subjects who do not
provide written informed consent to participate.

Research Plan: Approximately 100 subjects will be randomly assigned to either metformin or
placebo therapy. It is anticipated that enrollment for this pilot study could be
accomplished within 12 months. Subjects will be prospectively followed for 6 months in
duration as part of the pilot study. At time of hospital discharge or initial clinic visit,
subjects will be provided with an educational package on heart failure and type 2 diabetes.
They will also be provided with a medication Dosette to help maintain compliance to their
medications and a clinical event diary to record clinical events in the community setting.
To avoid medication intolerance, the dose of the study medication will be titrated slowly
over a 2 week period in the community. Research coordinators will contact subjects weekly
for the first 2 weeks to recommend dosage titration if warranted. All subjects will complete
a six minute walk at both baseline at the final 6 month follow-up visits. Throughout the
study, subjects will be contacted at monthly intervals for assessment of clinical endpoints.
Subjects will return to the heart function clinic at 3 and 6 months for clinical assessment
and to complete laboratory blood work. In addition, health related quality of life measures
(i.e., EQ5D, KCCQ, RAND12) will also be collected at both baseline and the 6 month final
follow-up visit.

Study outcomes: The primary outcome of the study will be a combined endpoint of all-cause
mortality and all cause-hospitalization. Secondary endpoints include the individualized
components of the primary outcome, development of lactic acidosis requiring urgent medical
attention, change in A1c, change in six minute walk, and change in health related quality of
life measures.

Data Analysis: As a pilot/feasibility stuy, a sample size of 100 patients was selected. An a
priori probability of committing a type 1 error (i.e., alpha level) of 0.05 will be applied
for all tests of statistical significance. All analyses will be conducted from an intention
to treat perspective. Invesigators, patients, and data analyst will be blinded to treatment
assignment. The primary outcome (all-cause mortality and hospitalization), secondary
outcomes for the individual components, and risk of the development of lactic acidosis will
be assessed using relative risk (RR) calculations. Secondary outcomes of change in A1c
values, six minute walk, and health related quality of life from baseline to 6 months will
be assessed using analysis of variance.
Study TypeInterventional
Study PhasePhase 3
Study DesignAllocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Single Group Assignment, Masking: Double-Blind, Primary Purpose: Treatment
Condition
  • Diabetes Mellitus, Type 2
  • Heart Failure, Congestive
InterventionDrug: Metformin
Study Arm (s)Not Provided

Recruitment Information[ + expand ][ + ]

Recruitment StatusTerminated
Estimated Enrollment100
Estimated Completion DateMay 2007
Estimated Primary Completion DateMay 2007
Eligibility Criteria
Inclusion Criteria:

- All subjects with physician-diagnosed symptomatic heart failure (NYHA class I, II,
III, IV) and type 2 diabetes.

A diagnosis of type 2 diabetes defined as:

- a previous physician diagnosis of type 2 diabetes as documented in the subject's
clinical record or;

- receiving oral antihyperglycemic agents or;

- a new diagnosis of type 2 diabetes during the visit within the heart failure clinic
or hospital based on a fasting blood glucose ≥7.0 mmol/L or random blood glucose
≥11.1 mmol/L accompanied by acute metabolic decompensation or 2 hour plasma glucose
in a 75 gram oral glucose tolerance test ≥11.1 mmol/L.

Exclusion Criteria:

- subjects currently receiving greater than 1500 mg of metformin therapy per day

- subjects who are unwilling to change their antidiabetic regimens;

- subjects receiving insulin therapy;

- serum creatinine ≥ 180 μmol/L;

- A1c < 7.0 percent;

- inability to communicate (language barrier);

- dementia/mental illness;

- age < 18 years;

- subjects unwilling to complete self-monitoring of serum blood sugars during the trial
period.

- those participating in another heart failure or diabetes clinical trial involving
medication;

- severe comorbidities or foreshortened life expectancy;

- subjects who do not provide written informed consent to participate.
GenderBoth
Ages18 Years
Accepts Healthy VolunteersNo
ContactsNot Provided
Location CountriesCanada

Administrative Information[ + expand ][ + ]

NCT Number NCT00325910
Other Study ID NumbersApproval J-2865
Has Data Monitoring CommitteeNot Provided
Information Provided ByUniversity of Alberta
Study SponsorUniversity of Alberta
CollaboratorsNot Provided
Investigators Principal Investigator: Jeffrey A Johnson, PhD University Of Alberta, Alberta, Canada
Verification DateMay 2008

Locations[ + expand ][ + ]

University of Alberta Hospital
Edmonton, Alberta, Canada, T6G 2B7
Misericordia Hospital
Edmonton, Alberta, Canada, T5R 4H5