The SGLT2 inhibitor medicines have changed how heart failure is managed. Originally sodium-glucose cotransporter 2 (SGLT2) inhibitors were used to lower blood sugar levels in people who have type 2 diabetes. We now know that they can also treat and prevent complications from heart failure, even in people who do not have diabetes. Farxiga (far-see-guh) is one of the SGLT2 inhibitors. It was approved in 2020 for people with one type of heart failure. Farxiga gained approval for people with other types of heart failure in 2023.
How Does Farxiga Work for Heart Failure?
Heart failure means your heart is not pumping as well as it should be. Farxiga treats heart failure by helping your body get rid of extra sugar and salt. Your body gets rid of extra water with the sugar and salt. This helps to lower your blood pressure a little bit. It also reduces how hard your heart works to pump blood throughout your body. Together these things improve heart failure by improving your heart's ability to pump.
What Types of Heart Failure Was Farxiga Studied In?
Farxiga was studied in three types of heart failure:
- Heart failure with a reduced ejection fraction (HFrEF) or systolic heart failure
- Heart failure with a preserved ejection fraction (HFpEF) or diastolic heart failure
- Heart failure with a mid-range ejection fraction (HFmrEF)
Ejection fraction is the percentage of blood in your heart that is pumped out with each heartbeat to the rest of your body.
HFrEF is when your heart has a pump problem. Your heart is not pumping as well as it should be to push the blood out of your heart to the rest of your body. People with HFrEF have a low ejection fraction, usually <40%.
HFpEF is when your heart has a filling problem. Your heart muscle is stiff, and it does not relax well for your heart to fill up with blood between each heartbeat. People with HFpEF have an ejection fraction of 50% or higher.
HFmrEF falls somewhere in between HFrEF and HFpEF. People with HFmrEF have an ejection fraction between about 41% and 49%.
How Was It Studied to Treat Heart Failure, and What Benefits Were Seen?
Early studies showed that in people with type 2 diabetes who have heart disease or risk factors for heart disease, Farxiga lowers your risk of being admitted to the hospital for heart failure. But it wasn't known if Farxiga would have that same benefit in people who did not have type 2 diabetes or in people who already had heart failure.
Two clinical studies were done to see if Farxiga was safe and effective for treating heart failure compared to a placebo containing no medicine. People in the studies did not know whether they were getting Farxiga or the placebo. The study measured worsening heart failure (defined as the need for urgent treatment for heart failure or and admission to the hospital for heart failure) or prevention of death (most often due to heart problems).
People in the first study had HFrEF and were between the ages of 55 and 77. Most people had New York Heart Association (NYHA) class II or III heart failure. The average ejection fraction was about 30%. About half of the people in the study had type 2 diabetes. Most people were taking other medicine(s) commonly used to treat heart failure, such as a water pill (>90%), ACE inhibitor, ARB, or ARNI (94%), beta-blocker (96%), or spironolactone or eplerenone (71%).
After about 18 months, a significantly lower percentage of people with HFrEF who took Farxiga (16.3%) had either worsening heart failure or died due to heart problems compared to those who took placebo (21.2%).
People in the second study had HFpEF or HFmrEF and were between the ages of 62 and 80 years old. Most people had NYHA class II or III heart failure with an average ejection fraction of between 49% and 59%. Just under half of the people in the study had type 2 diabetes and almost 90% had high blood pressure.
After just over 2 years, a significantly lower percent of people with HFpEF or HFmrEF who took Farxiga (16.4%) had either worsening heart failure or died due to heart problems compared to those who took placebo (19.5%).
Your results may differ from what was seen in clinical studies.
How Strong Is the Evidence for It?
The guidelines for how to treat people with heart failure include strong recommendations on when the SGLT2 inhibitors should be used. Farxiga is approved to treat all of these types of heart failure. According to the latest guidelines, this is how SGLT2 inhibitors should be used.
HFrEF: Use SGLT2 inhibitors to reduce your risk of a hospital admission for heart failure and to reduce your risk of dying from heart problems, even if you do not have type 2 diabetes.
HFmrEF and HFpEF: SGLT2 inhibitors can help lower your risk of being hospitalized for heart failure and help reduce your risk of dying from heart problems.
Are There Additional Potential Benefits Based on the Studies?
In the study of Farxiga in people with HFrEF, heart failure symptoms were evaluated. People in the study answered questions about their specific heart failure symptoms when they started the study and again about 8 months later. The questions asked about how heart failure impacted these things:
- Ability to shower or take a bath
- Ability to walk 1 block on level ground
- Ability to enjoy hobbies
- Ability to do household chores
- Swelling in your leg, ankle, or feet
- Difficulty breathing
- Ability to sleep lying flat
- Impact on enjoying life
After just over 8 months, people taking Farxiga had fewer heart failure symptoms compared to people who took a placebo with no medicine. People who take Farxiga may feel like heart failure symptoms have less of an impact on day-to-day activities compared to people who do not take Farxiga.
What Are the Possible Serious Side Effects?
There are a few extremely rare but serious side effects that can happen if you take Farxiga.
Necrotizing fasciitis of the perineum (Fournier’s gangrene). This is an infection that causes death of skin and tissue in the area between your genitals (vagina or penis) and your anus (the hole where your stool comes out). When Farxiga was studied in people with heart failure, Fournier’s gangrene was not reported in any people taking Farxiga. If you have fever or pain, tenderness, or swelling in or around your genitals or anus, you should seek medical attention right away.
Amputations. When Farxiga was studied for people with heart failure, amputations were extremely rare. They were not any more common in people who took Farxiga compared to people who took a placebo without medicine. Things that may increase your risk of amputations include nerve damage (especially in your feet or legs), poor circulation, smoking, and foot ulcers. If you develop an ulcer or sore on your foot or lower leg, have it checked by your health care provider.
Fractures (broken bones). When Farxiga was studied for people with heart failure, fractures were not any more common in people who took Farxiga compared to people who took placebo with no medicine.
Farxiga may cause dehydration. People with heart failure often take diuretics (water pills) to help control their heart failure symptoms, like swelling in your feet or legs or difficulty breathing. Diuretics can increase your risk of dehydration. These are some things you can do to help you stay hydrated.
- Drink water throughout the day.
- Avoid skipping meals.
- Eat a balanced diet with fruit and vegetables.
- Limit the amount of caffeine you have.
- Limit the amount of alcohol you drink.
- Drink more when it is hot or if you have a fever, diarrhea, or are vomiting.
How Can I Get Farxiga?
Farxiga requires a prescription from a health care provider. You can get it at any pharmacy.
There is a savings card available from the manufacturer that may allow you to pay $0 for your prescription. Whether you are eligible depends on whether you have prescription insurance and what type of insurance you have. You can find out more by calling 855-3FARXIGA (855-332-7944) or at www.farxiga.com/savings-support/.