Arteries are blood vessels that carry blood away from your heart. Pulmonary arterial hypertension (PAH) is a condition where you have high blood pressure in the arteries that go from your heart to your lungs. In people with PAH, the arteries become narrow, stiff, or thickened. This makes your heart work harder to pump blood and may lead to heart failure.
PAH is a long-term (chronic) condition that tends to worsen over time. It more commonly affects women. Symptoms commonly include shortness of breath, tiredness, chest discomfort, dizziness, or swelling in the legs and ankles. These symptoms can make it hard to walk and move around.
While there is no cure for PAH yet, treatments are available to manage symptoms and help you stay more active. One option is Tyvaso (treprostinil). Tyvaso is an inhaled medicine that is FDA-approved to improve exercise ability in adults with PAH.
Continue reading for answers to common questions about Tyvaso for PAH.
How Does Tyvaso Work?
Tyvaso is an inhaled medicine. It contains the active medicine treprostinil, which mimics the effect of a natural substance in your body called prostacyclin. It helps blood vessels relax and widen. It also helps prevent platelets (a type of blood cell) from sticking together. This can make it easier for your heart to pump blood to your lungs.
Is Tyvaso Right for My PAH?
To know if Tyvaso is right for you, your health care provider will look at your medical history, including the type of pulmonary hypertension you have, your symptoms, other medicines, and your overall health.
Pulmonary hypertension is a general term for high blood pressure in the lungs. There are five types, called World Health Organization (WHO) Groups. Tyvaso is FDA-approved for adults with pulmonary arterial hypertension (PAH), which is WHO Group 1.
Your health care provider will also look at your symptoms and how much they limit your physical activity. PAH symptoms are grouped into four levels, called World Health Organization (WHO) functional classes. These classes are based on a similar system used for heart failure, known as the New York Heart Association (NYHA) classes. A lower number means milder symptoms, while a higher number means more severe symptoms. In general, the classes describe how much your symptoms limit your physical activity:
- Class I: You have no symptoms with normal activity.
- Class II: You feel short of breath or tired during normal activity.
- Class III: Even light activity causes shortness of breath or fatigue.
- Class IV: You have symptoms even while resting.
In studies where Tyvaso was shown to work, most people had class III PAH symptoms.
Talk with your health care provider to see if Tyvaso may be an option for you.
How Was Tyvaso Studied for PAH?
A 12-week clinical study called TRIUMPH examined how well inhaled Tyvaso works for people with PAH who are already being treated with an oral medicine (either bosentan or sildenafil).
People were not allowed to enter the study if they were pregnant or breastfeeding, had other serious health conditions not related to PAH, had recently taken certain other PAH or experimental treatments, or had recently changed their PAH medicines.
The study included 235 adults with confirmed PAH (WHO Group 1) who were also taking bosentan or sildenafil for at least three months. Some people were also using other treatments, such as oxygen, blood pressure medicines, or water pills (diuretics). At the start of the study:
- The average age of participants was 54 years (range, 18 to 75 years).
- Most (82%) were women, and the rest were men.
- The average six-minute walk distance was about 346 meters in the Tyvaso group and 351 meters in the placebo group.
- Almost all (98%) belonged to class III (had symptoms with light activity), and the rest came under class IV (had symptoms even at rest).
- 70% of people were taking bosentan, and 30% were taking sildenafil.
Participants in this study were randomly assigned to use either Tyvaso or a placebo (an inhaled treatment with no active medicine) four times a day for 12 weeks. Neither the participants nor the researchers knew who was receiving Tyvaso.
The main goal of the study was to see how much the six-minute walk distance changed after 12 weeks, measured at the time when the medicine was working at its strongest (between 10 and 60 minutes after a dose, called “peak” effect). Researchers compared how much the six-minute walk distance changed from the start of the study between the two groups.
Researchers also looked at other outcomes, such as walking distance measured at least four hours after a dose (called “trough”), walking distance at six weeks, and PAH symptoms.
What Are the Benefits of Tyvaso for PAH Based on Studies?
The main results showed that Tyvaso improved exercise ability in people with PAH. After 12 weeks, people taking Tyvaso walked 20 meters farther than people taking a placebo, when measured at peak effect (about 10 minutes to an hour after a dose). This was the median, meaning the middle value in the set of results.
While not the main goals of the study, here are some of the other median results:
- At six weeks, people using Tyvaso walked 19 meters farther than those using a placebo.
- At 12 weeks, people using Tyvaso walked 14 meters farther than those on placebo when walking distance was measured at least four hours after dosing (“trough”).
The greatest improvement was seen in people who had the lowest walking distance at baseline. At 12 weeks, people in this group who used Tyvaso walked a median of 49 meters farther than those who used a placebo.
Experts say that people with PAH need to walk at least 33 meters farther on the six-minute walk test for it to count as a meaningful improvement. So, the improvement seen with Tyvaso in the study may not reflect a noticeable change in daily activity for everyone.
It is also important to note that people generally could walk farther when Tyvaso was working at its strongest (peaks about 10-60 minutes after a dose). Typically, Tyvaso doses are spaced about four hours apart, and the effects gradually wear off as you get closer to your next dose. This means you may want to plan treatment accordingly. For example, you might schedule a dose right before exercise, errands, or social events so the medicine is working at its strongest when you need it most. Your health care provider can help you decide how to time your doses during the day.
Individual results may be different from what was seen in studies. Talk with your health care team about the plan to monitor how well your PAH treatment plan is workin
What Do We Know About Long-Term Effects of Tyvaso for PAH?
After the 12-week main study ended, 206 people chose to continue using Tyvaso in a longer-term extension study. Most were women (81%), with an average of 54 years, and most had class III symptoms. At the start of this phase, the average six-minute walk distance was about 349 meters. People had a checkup every three months to see how they were doing.
Overall, the results suggest that inhaled treprostinil provided continued benefit for people with PAH who remained on treatment for up to two years. The table below summarizes the results among people who stayed on treatment.
| Change in 6-minute walking distance (median) compared to the start of extension study | Survival rate (Percentage of people who were still alive) | Percentage of people whose PAH did not get worse | |
|---|---|---|---|
| 6 months | +28 meters | (not reported) | (not reported) |
| 1 year | +31 meters | 97% | 82% |
| 1.5 years | +32 meters | 94% | 74% |
| 2 years | +18 meters | 91% | 69% |
Researchers continued to follow up with people who continued using Tyvaso and reported that 82% were still alive after three years.
However, note that the long-term extension and follow-up study did not include a placebo group. Since there was no comparison group, these results do not show whether Tyvaso had an effect on how long people lived.
Individual results can vary. Talk with your health care team about the plan to monitor how well your PAH treatment plan is working.
What Can I Do to Prevent or Manage Side Effects of Tyvaso?
Most people tolerate Tyvaso well. But, as with most medicines, side effects are possible. You can prevent or manage most of the side effects with careful monitoring and by knowing when to contact your health care provider.
Some common side effects of Tyvaso are cough, throat pain or irritation, headache, nausea and other stomach-related effects, dizziness, reddening of the face and neck (flushing), and fainting.
Using Tyvaso properly may help lower the chance of throat discomfort. Review your technique with your care team and follow the steps in the Instructions for Use that comes with your medicine.
Your health care provider may suggest ways to prevent or manage throat irritation, such as drinking some cold water or hot tea before using Tyvaso. Or you may want to try using an over-the-counter (OTC) sore throat spray or lozenge to numb your throat before a dose.
This is not a complete list of Tyvaso side effects. Tell your health care provider if side effects feel severe, worsen, or do not improve.
What Is the Difference Between Tyvaso and Tyvaso DPI?
Both Tyvaso and Tyvaso dry powder inhaler (DPI) contain the same active medicine (treprostinil) and are used to treat the same conditions. The main difference is how the medicine is delivered:
- Tyvaso is a liquid that is inhaled using a nebulizer device, which is a small machine that turns the liquid into a mist you inhale. Tyvaso nebulizer treatments require preparation, setup, and cleaning. It usually takes abouttwo to three minutes to inhale each dose.
- Tyvaso DPI is a dry powder inhaled using a small, handheld inhaler. The DPI device is smaller and does not require charging or cleaning. It usually takes one to two seconds to inhale each dose.
A study was done to see whether people could safely switch from the Tyvaso nebulizer to Tyvaso DPI and how satisfied they were with the change. The study included people who had been using Tyvaso nebulizer treatment for at least three months, and then switched to Tyvaso DPI. After three weeks, the results showed that switching to Tyvaso DPI was safe and well-tolerated. Most people were highly satisfied and chose to continue using the DPI.
You and your health care provider can decide which option is best for you based on your needs and preferences.
Is There Any Cost Assistance Available?
Financial support options, including Tyvaso copay and patient assistance programs, are available from United Therapeutics Cares. For more information, visit this website or call 844-864-8437.
