A Study of Pre-operative Metformin in Prostate Cancer

Overview[ - collapse ][ - ]

Purpose This study will investigate the effect of neoadjuvant metformin therapy in the inhibition of growth and proliferation of prostate cancer cells prior to radical prostatectomy.
ConditionProstate Cancer
InterventionDrug: Metformin
PhasePhase 2
SponsorUniversity Health Network, Toronto
Responsible PartyUniversity Health Network, Toronto
ClinicalTrials.gov IdentifierNCT00881725
First ReceivedApril 14, 2009
Last UpdatedJune 18, 2012
Last verifiedJune 2012

Tracking Information[ + expand ][ + ]

First Received DateApril 14, 2009
Last Updated DateJune 18, 2012
Start DateJune 2009
Estimated Primary Completion DateJune 2012
Current Primary Outcome MeasuresDifference in Ki67 staining [Time Frame: Pre-Surgery] [Designated as safety issue: No]
Current Secondary Outcome Measures
  • Other immunohistochemical assays: IR, IGF-1R, p70S6K, AMPK, MVD, Cleaved caspase 3, PTEN, c-Myc [Time Frame: Pre-Surgery] [Designated as safety issue: No]
  • Differences in measures of insulin resistance: waist/hip ratio, fasting blood glucose, post-prandial blood glucose, weight [Time Frame: Pre-Surgery, Post-Surgery] [Designated as safety issue: Yes]
  • Differences in PSA levels [Time Frame: Pre-Surgery, Post-Surgery] [Designated as safety issue: No]
  • Incidence of adverse events, serious adverse events, and grade 3-4 toxicities [Time Frame: Pre-Surgery, Post-Surgery] [Designated as safety issue: Yes]

Descriptive Information[ + expand ][ + ]

Brief TitleA Study of Pre-operative Metformin in Prostate Cancer
Official TitleA Phase II, Open Label Assessment of Neoadjuvant Intervention With Metformin Against Tumour Expression of Signaling
Brief Summary
This study will investigate the effect of neoadjuvant metformin therapy in the inhibition of
growth and proliferation of prostate cancer cells prior to radical prostatectomy.
Detailed Description
Prostate cancer is the most commonly diagnosed malignancy in men in North America, with
close to a quarter of a million cases diagnosed in 2007 alone (Joshua et al, 2007). The
activation of the PTEN/ AKT pathway is thought to be of importance in prostatic
carcinogenesis as it correlates with a poor prognosis (Yoshimoto et al, 2007) (Schmitz et
al, 2007). Components of this cellular pathway have pleiotropic targets including the mTOR
complex. In model systems, tumours exhibiting activation of PI3K/AKT kinase are sensitive
to mTOR inhibitors.

Metformin (1,1-dimethylbiguanide hydrochloride) belongs to the biguanide class of oral
hypoglycaemic agents and is a commonly prescribed medication for a number of conditions. It
is the first-line drug of choice for the treatment of type 2 diabetes. Its mechanism of
action is thought to be the primary inhibition of hepatic glucose output through inhibition
of gluconeogenesis. Subsequently, metformin causes a decline in the circulating insulin
level (Hundal et al, 2000).

Metformin causes inhibition of the mTOR complex. The mTOR complex is primarily inhibited
through activation of AMPK (a component of the PTEN/AKT pathway). Metformin causes reduced
hepatic glucose output leading to decreased levels of circulating insulin which causes the
secondary inhibition of the mTOR complex. Metformin has also been shown to inhibit cyclin
D1 expression and retinoblastoma protein (Rb) phosphorylation. Inhibition of Cyclin D1 and
Rb phosphorylation cause inhibition of G1/S phase transition of the cell cycle. This
results in the inhibition of cell proliferation (Matsushime et al, 1994).

This study will investigate the effect of neoadjuvant metformin therapy in the inhibition of
growth and proliferation of prostate cancer cells prior to radical prostatectomy.
Study TypeInterventional
Study PhasePhase 2
Study DesignEndpoint Classification: Safety/Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Treatment
ConditionProstate Cancer
InterventionDrug: Metformin
500mg tablets t.i.d. for 4-12 weeks prior to Radical Prostatectomy
Study Arm (s)Experimental: Metformin
500mg t.i.d. for 4-12 weeks prior to Radical Prostatectomy

Recruitment Information[ + expand ][ + ]

Recruitment StatusTerminated
Estimated Enrollment24
Estimated Completion DateJune 2012
Estimated Primary Completion DateMarch 2011
Eligibility Criteria
Inclusion Criteria:

1. 1. Patients with histologically confirmed prostate cancer involving at least 20% of
at least one unfragmented biopsy core;

2. Over the age of 18 and under the age of 75;

3. Ability to read and understand the consent form, either alone or with the aid of a
translator

4. ECOG performance status less than or equal to 2 (Karnofsky greater than or equal to
60%);

5. Patients must have their TRUS biopsy performed at UHN (or at an outside institution
if tissue accession can be arranged) in the last 3 months;

6. Patients must have normal organ and marrow function as defined by the following
criteria:

1. Absolute neutrophil count greater than or equal to 1,500/uL

2. Platelets greater than or equal to 100,000/uL

3. Total bilirubin less than or equal to 1.5 X institutional ULN

4. AST(SGOT)/ALT(SGPT) less than or equal to 1.5 X institutional ULN

5. Creatinine less than or equal to 1.4 X institutional ULN

Exclusion Criteria:

1. Patients who on initial assessment are found to be on treatment with any drug used
for the treatment of any form of diabetes, or patients that begin treatment for any
form of diabetes during the course of the study;

2. Patients may not be receiving any other investigational, herbal or anticancer agents
while on study;

3. Uncontrolled intercurrent illness including, but not limited to, ongoing or active
infection, congestive heart failure (NYHA Class 3 or greater), cirrhosis with a
Child-Pugh level of B or greater or evidence of cardiac dysfunction, unstable angina
pectoris, cardiac arrhythmia, active peptic ulcer disease, clinically significant
gastrointestinal conditions (e.g. Crohns disease, ulcerative colitis), COPD or
psychiatric illness/social situations that would limit compliance with study
requirements;

4. Active malignancy at any other site excluding squamous cell or basal cell carcinomas
of the skin

5. Radiotherapy within the past 4 weeks;

6. Patients with a current history of alcohol intake (>2 standard drinks/day) or binge
drinking (5 or more drinks (male), or 4 or more drinks (female)) in one session of
1-3 hours;

7. Past history of lactic acidosis or risk factors for lactic acidosis such as
congestive heart failure (NYHA Class 3 or greater), hypoxia (resting PO2 < 91%) or
renal insufficiency (eGFR < 60 mls/min)

8. Patients taking systemic glucocorticoids or estrogenic compounds.

9. Patients with known hypersensitivity or allergy to metformin or any of its
excipients.

10. Patients with a history of impaired liver or kidney function.
GenderMale
Ages18 Years
Accepts Healthy VolunteersNo
ContactsNot Provided
Location CountriesCanada

Administrative Information[ + expand ][ + ]

NCT Number NCT00881725
Other Study ID NumbersPMH-ANIMATE-001
Has Data Monitoring CommitteeYes
Information Provided ByUniversity Health Network, Toronto
Study SponsorUniversity Health Network, Toronto
CollaboratorsJewish General Hospital
Investigators Principal Investigator: Anthony Joshua, M.D. University Health Network, Toronto
Verification DateJune 2012

Locations[ + expand ][ + ]

University Health Network
Toronto, Ontario, Canada, M5G2M9