Immune thrombocytopenia (ITP) is a rare blood disorder in which the immune system mistakenly attacks and destroys platelets. Platelets are small blood cells that play a critical role in helping your blood clot. Without enough platelets, people with ITP may bruise easily, bleed for long periods after an injury, or have frequent nosebleeds or gum bleeding. In severe cases, bleeding may occur in organs like the brain, stomach, or spine.
Wayrilz (rilzabrutinib) is a prescription medicine approved by the FDA in 2025 for adults with persistent or chronic ITP who did not respond well enough to another treatment.
How Does Wayrilz Work?
In people with ITP, the immune system mistakenly attacks platelets. Wayrilz works by lowering the signals from a protein in your body called BTK (Bruton's tyrosine kinase). By lowering these signals, Wayrilz helps to protect platelets. This medicine works to help prevent the marking of platelets for destruction and the destruction by your immune system.
How Do I Take Wayrilz?
Wayrilz is a tablet that is taken by mouth twice daily. The tablet should be swallowed whole with a glass of water. If you take medicines known as antacids or histamine H2 receptor antagonists, take Wayrilz at least two hours before the antacid or histamine H2 receptor antagonist. Talk with your health care provider if you are unsure if you are taking either an antacid or histamine H2 receptor antagonist. Some of these medicines are available over the counter (OTC).
How Was Wayrilz Studied?
The LUNA3 study looked at how well Wayrilz works in adults with either persistent or chronic (present for a year or more) ITP. People needed to have two platelet counts below 30,000, taken at least five days apart, and no platelet count above 35,000 within 14 days before starting treatment. People also needed to have responded to then failed certain treatments for ITP and needed to be unable to use any other ITP therapy for reasons such as it not working or causing certain side effects.
People were assigned to get either Wayrilz or a placebo (containing no medicine) twice daily for 24 weeks. Neither the people in the study nor the researchers knew who was receiving what treatment. People could continue to take their regular, unchanged doses of either a corticosteroid or a medicine called a thrombopoietin receptor agonist for ITP. Rescue medicines to quickly raise platelet counts were permitted if platelet levels fell too low or if there were bleeding symptoms.
The main goal of the study was to measure how many people had a "durable platelet response." This meant having platelet levels in a safe range for most of the last 12 weeks of the study without needing rescue medicines to increase their platelet levels. To count as a platelet response, people also needed to have at least two instances of platelet levels in a safe range during the final six weeks of the study. Researchers also tracked how many weeks platelet levels stayed in a safe range without the need for rescue medicines, how quickly platelet levels improved, how often rescue medicines to increase platelet levels were needed, and whether people had tiredness.
The LUNA3 study took place between December 2020 and September 2023. Of the 202 patients, 62% were White, 32% were Asian, and 6% were of another race. People ranged in age between 18 and 80, 63% were women, and 28% had their spleen removed. Platelet counts were below 15,000 for 48% and were at least 15,000 for 52%. Most people had tried several other medicines for ITP, with about half having tried five or more different therapies. Most (96%) people had used a corticosteroid.
What Are the Main Benefits?
Results from the LUNA3 study showed that Wayrilz helped people living with persistent or chronic ITP. A durable platelet response was achieved by 23% of the133 people receiving Wayrilz, compared with none of the 69 receiving a placebo. Platelet counts began to improve within the first few weeks for people who took Wayrilz, and they went on to have a durable platelet response.
Your results may differ from what was seen in the clinical study.
Are There Other Potential Benefits Based on the Study?
Wayrilz reduced the need for rescue medicines for the treatment of dangerously low platelet levels. Only about one-third of people in the Wayrilz group (33%) needed rescue medicine during the study, compared with more than half (58%) of people in the placebo group. This translates to a 52% reduction in the use of rescue medicines for people who took Wayrilz.
People taking Wayrilz also had improvements in tiredness. Improvement in tiredness was seen as early as week five and continued through the study.
Your results may differ from what was seen in the clinical study.
What Can I Do to Manage Side Effects?
Your health care provider will monitor you while you are taking Wayrilz. Before and during treatment, your health care provider will likely check how well your liver is working. Tell your health care provider right away if you have stomach pain, vomiting, dark urine, or yellowing skin or eyes. Keep all appointments to have your blood checked. If your health care provider finds that you have a liver injury as a result of Wayrilz, treatment with Wayrilz will be stopped.
Wayrilz may increase your risk of serious infections. Your health care provider will monitor you for any signs or symptoms of infection during treatment. Tell your health care provider right away if you get a fever, chills, flu-like symptoms, a cough, or pain when peeing (urinating). Some infections can be life-threatening. The risk of problems is lowered the sooner an infection is diagnosed and treated by your health care provider.
Is There Any Cost Assistance Available?
There is a copay assistance program from the drugmaker 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 at consentrbdpatients.iassist.com/ or by calling 833-723-5463.