Type 1

Should people with type 1 diabetes take a drug that helps pass excess sugar out of the blood via the urine? That’s the question which has been raised by Bristol-Myers Squibb, the company behind the relatively new diabetes medication dapagliflozin (Farxiga).

SGLT-2 inhibitors is a class of drugs which encourage the kidneys to pass more glucose out of the body via the urine. Dapagliflozin is one of the drugs from this class that has been approved for use by the FDA (Food and Drug Administration).

Poorly controlled type 1 diabetes

The study examined the effects of SGLT-2 inhibitors over 2 weeks compared with a placebo. 70 participants with type 1 diabetes took part in the study. The participants had less well controlled diabetes with HbA1c results of between 7 and 10% going into the study.

Participants were randomly assigned in to 4 groups to receive doses of dapagliflozin of 1mg, 2.5mg, 5mg or 10mg over a 7 day period. The results were compared against placebo in another 7 day period. The participants had stable insulin doses which were largely kept unchanged through the study, with changes in doses permitted if blood glucose results were too low or significantly too high.

Lower blood sugar levels

Doses of dapagliflozin were associated with lower blood glucose levels and lower insulin doses than when placebo was taken. However, the researchers note that the reduction in blood glucose levels was not enough to show statistical significance.

Within the study, there was one incident of severe hypoglycemia which occurred in one of the participants on the 10mg dose of dapagliflozin. One incident could be an anomaly but larger studies will need to prove this that severe hypos on dapagliflozin is a rare event if the drug is to be considered for approval. No episodes of ketoacidosis were recorded whilst on placebo or dapagliflozin.

The researchers conclude that the study provides hope that the use of SGLT-2 inhibitors may prove to be effective in larger scale studies but there is clearly doubt over whether these drugs will be appropriate.

Side effects

SGLT-2 inhibitors are most effective in people with consistently high blood glucose levels. This means that the drugs can help take the edge off high blood sugar levels but, for people with less stable insulin doses or wide variability in blood glucose results, drugs such as dapagliflozin could increase the risk of hypos.

The other factor to consider with adding another drug in addition to insulin is the risk of additional side effects occurring. SGLT-2 inhibitors have been shown to increase the risk of urinary tract infections and yeast infections in people with type 2 diabetes. Other side effects associated with these drugs in clinical trials have been small reductions in kidney function and possible increases in risk of bone fractures.

If you have type 1 diabetes and are currently struggling with too high blood glucose levels, it’s important to see your doctor who will be able to help you to take steps to better manage your diabetes.