Metformin

Background

The LSCMMG supports the use of immediate release metformin for reduction in the risk or delay of the onset of type 2 diabetes mellitus in adult, overweight patients with impaired glucose tolerance and/or impaired fasting glucose, and/or increased HbA1c who are:

• at high risk for developing overt type 2 diabetes mellitus and
• still progressing towards type 2 diabetes mellitus despite implementation of intensive lifestyle change for 3 to 6 months

If the patient cannot tolerate immediate release metformin, consider using modified release metformin.

Background

Glucophage SR (metformin modified release) has had a licence extension to cover use:
for reduction in the risk or delay of the onset of type 2 diabetes mellitus in adult, overweight patients with impaired
glucose tolerance and/or impaired fasting glucose, and/or increased HbA1c who are:

• at high risk for developing overt type 2 diabetes mellitus and
• still progressing towards type 2 diabetes mellitus despite implementation of intensive lifestyle change for 3 to 6 months

The manufacturer of Glucophage SR submitted data from 7 controlled clinical trials in support of the licence extension – all used standard release metformin. The most important studies supporting the licence extension were the DPP and DPPOS studies which demonstrated metformin significantly reduced diabetes incidence in patients who were at high risk of developing diabetes compared to control.

NICE Public Health guideline [PH38], Type 2 diabetes: prevention in people at high risk states:
1.19.1 Use clinical judgement on whether (and when) to offer metformin to support lifestyle change for
people whose HbA1c or fasting plasma glucose blood test results have deteriorated if:

• this has happened despite their participation in intensive lifestyle-change programmes or
• they are unable to participate in an intensive lifestyle-change programme, particularly if they have a BMI greater than 35.
  And

1.19.5 Start with a low dose (for example, 500 mg once daily) and then increase gradually as tolerated, to 1500–2000 mg daily. If the person is intolerant of standard metformin consider using modified-release metformin.

NICE acknowledges the licence extension for Glucophage SR and continues, stating:
Other standard-release and modified-release metformin products may similarly extend their marketing authorisations in the future.

See the General Medical Council’s Prescribing guidance: prescribing unlicensed
medicines for information on off-label prescribing