The U.S. Food and Drug Administration (FDA) has approved a new treatment for type 2 diabetes, a fixed-dose therapy combining canagliflozin and metformin hydrochloride into a single tablet (Invokamet, Janssen Pharmaceuticals).
"Canagliflozin works with the kidney to promote the loss of glucose in the urine, whereas metformin decreases the production of glucose in the liver and improves the body's response to insulin," said Richard Aguilar, MD, medical director of Diabetes Nation.
The drug is intended to supplement diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus that is not adequately controlled by treatment that includes one drug or both drugs taken separately, according to its manufacturer. It is available in formulations containing 50 mg or 150 mg of canagliflozin and 500 mg or 1000 mg of metformin. The recommended dosing is twice daily.
In Phase III clinical trials, the most common side effects were female genital mycotic (fungal) infections, urinary tract infections and increased urination. The most common adverse reactions due to initiation of metformin are diarrhea, nausea/vomiting, flatulence, asthenia, indigestion, abdominal discomfort and headache. Use of the combination medication can increase the risk of hypoglycemia when it is combined with insulin or a medication that increases insulin levels (such as a sulfonylurea).
Also, use of metformin can cause a rare but serious condition called lactic acidosis (a build-up of lactic acid in the blood), which can result in death. Lactic acidosis is a medical emergency and must be treated in the hospital. Symtoms include feeling very weak or tired; unusual muscle pain; trouble breathing; unusual sleepiness or sleep longer than usual; stomach pains, nausea, or vomiting; dizziness or lightheadedness; or a slow/irregular heartbeat. Those who have kidney or liver problems; congestive heart failure; drink alcohol very often (or drink a lot of alcohol in short-term); get dehydrated; have surgery; have a heart attack, severe infection or stroke; or are aged 80 or more years and have not had their kidneys tested have a greater chance of getting lactic acidosis.