Introduction

Dapagliflozin (trade name EU: Forxiga, U.S.: Farxiga) has been approved in Germany since November 2012 for the treatment of type 2 diabetes in adults who can't reduce their blood sugar levels enough through diet and exercise alone. Since March 2019, it has also been available for adults with type 1 diabetes who are overweight.

Diabetes is a metabolic disease that affects many different parts of the body. In patients with type 1 diabetes, the pancreas can only produce insulin in small quantities or not at all. They therefore have to inject insulin regularly. In type 2 diabetes, the pancreas still produces enough insulin at first, but the body’s cells gradually lose the ability to absorb and use the insulin. If the blood sugar levels can't be lowered enough by diet changes and exercise, medications are used to regulate them.

Dapagliflozin is a treatment option for people with type 2 diabetes who don’t tolerate the standard medication metformin. Dapagliflozin may also be used in addition to other blood-sugar-lowering drugs (including insulin) if they don't provide adequate control of blood sugar levels. People with type 1 diabetes may use dapagliflozin in addition to insulin if their BMI is above 27 kg/m² and if insulin alone can't lower blood sugar levels enough.

Application

Dapagliflozin is available as tablets at a dose of 5 or 10 mg. The recommended dose is 10 mg once a day for people with type 2 diabetes, and 5 mg a day for people with type 1 diabetes.

If the drug is combined with other blood-sugar-lowering tablets or insulin, their doses may have to be adjusted by a doctor to prevent hypoglycemia (too low blood sugar).

Other treatments

Various medications are available for the treatment of type 2 diabetes in adults. They can either be used alone or in combination with each other, and include metformin, sulphonylureas and insulin.

For adults with type 1 diabetes, various types of insulin are available.

Assessment

In 2019, the Institute for Quality and Efficiency in Health Care (IQWiG, Germany) last looked into the advantages and disadvantages of dapagliflozin compared with the standard treatments for adults who have type 1 or type 2 diabetes. The manufacturer only provided suitable data for overweight adults who have type 1 diabetes. The data was taken from two studies involving a total of 575 people only for overweight adults who have type 1 diabetes. Half of them were given dapagliflozin and insulin, and the other half received only insulin. The participants were monitored for about one year. The study showed the following results in these patients:

What are the advantages of dapagliflozin?

HbA1c values: The studies suggest that using both dapagliflozin and insulin has an advantage here. Doctors measure HbA1c values to see how well blood sugar levels are regulated over the longer term. This measurement shows the average blood sugar levels over the last few months. Regulating HbA1c values over the long term is meant to prevent diabetes leading to other health problems (complications). However, from the available data it's not clear to what extent complications can in fact be prevented.

What are the disadvantages of dapagliflozin?

  • Genital infections: The studies showed that dapagliflozin has a disadvantage in terms of these side effects. Genital infections occurred in 15 of 100 patients who received both dapagliflozin and insulin, compared to only 4 of 100 patients who received insulin alone.
  • Gastrointestinal (stomach and bowel) problems: Using both medications was found to have a disadvantage here, too. Gastrointestinal problems occurred in 24 of 100 patients who received both dapagliflozin and insulin, compared to only 13 of 100 patients who received insulin alone.

No difference

  • General health and hypoglycemia (low blood sugar): There was no significant difference between "dapagliflozin plus insulin" and "insulin only" here.
  • There was no difference between these treatment approaches in terms of the following aspects either:
    • Severe side effects
    • Severe hypoglycemia
    • Worrying about hypoglycemia
    • Urinary tract infections

What remains unanswered?

The manufacturer didn't provide any suitable data concerning health-related quality of life and treatments stopped due to side effects. The data provided by the manufacturer concerning potentially fatal hyperglycemia (too high blood sugar) was incomplete.

More information

This information summarizes the main results of reviews produced by the Institute for Quality and Efficiency in Health Care (IQWiG, Germany). The reviews were commissioned by the German Federal Joint Committee (G-BA) as part of the “early benefit assessment of medications.” On the basis of these reviews and the hearings received, the G-BA passed a resolution on the added benefit of dapagliflozin (Forxiga, Farxiga) for the treatment of type 2 diabetes and type 1 diabetes.