Modeyso for Rare Glioma

Written by Christie Denton, PharmD, BCPS
Medically Reviewed by Ami Ishver, PharmD on September 09, 2025
5 min read

Modeyso (dordaviprone) is a once-weekly targeted oral medicine that was approved by the FDA in August 2025 for the treatment of a rare and aggressive form of brain cancer known as diffuse midline glioma. It has been shown to kill cancer cells and slow cancer growth in adults and children with cancer that is progressing (getting worse) despite previous therapy.

Modeyso is used to treat a type of recurrent brain cancer known as a diffuse midline glioma with a specific genetic mutation known as histone 3 (H3) K27M. Diffuse midline gliomas with the H3 K27M mutation are usually found in an area of the brain where the cancer cannot completely be removed with surgery. 

People with diffuse midline glioma usually receive radiation therapy for their cancer and have few treatment options available. Survival is usually low when this type of glioma comes back after initial treatment. The average survival is about 5 months after progression on first-line treatment. 

Modeyso is an oral medicine that is taken by mouth one time each week on the same day of the week. Modeyso should be taken on an empty stomach, either one hour before eating food or three hours after eating.

Modeyso comes as a capsule that is swallowed whole. If you or your child have difficulty swallowing the capsules, they can be opened and dissolved in a suitable liquid (sports drink, apple juice, lemonade, or water) to make it easier to swallow. 

If you plan to dissolve Modeyso in liquid, you should first count the number of capsules needed for your dose. Get a clean cup and empty the contents of each capsule into the cup by gently twisting and pulling open each capsule. Once the powder from the capsules is in your cup, add 1 or 2 tablespoons of liquid (sports drink, apple juice, lemonade, or water) and gently swirl to mix. The mixture may look chunky, which is normal. Swallow the mixture right away. After taking the mixture, add another 1 or 2 tablespoons of liquid to the cup to capture any remaining powder and gently swirl the cup. Swallow the remainder of the liquid.

If the mixture is being given to a child, an oral dosing syringe can be used to give the mixture by mouth. The mixture should be given within two hours of preparing it. If not used within two hours, throw it away.

After taking or giving the dose, rinse the cup out with warm running water, and wash your hands with warm soap and water.

Consider reading the “Instructions for Use” that comes with Modeyso the first time you take this medicine and each time you get a refill.

Data were combined from five studies to see if Modeyso was safe and effective for treating recurrent diffuse midline glioma. Modeyso was not compared to any other medicine or placebo. People taking Modeyso knew that they were receiving Modeyso.

A total of 50 people (46 adults and four children) diagnosed with diffuse midline glioma with the H3 K27M mutation that was progressive (getting worse) and measurable were included. Radiation treatment was not allowed within the last three months, and people had to be off chemotherapy medicine for a certain amount of time before getting Modeyso. People also had to be relatively well-functioning and on stable or decreasing doses of steroid medicine.

Modeyso was given once weekly except for one patient who got the medicine every three weeks. They continued Modeyso until their cancer got worse or they had a side effect that was not manageable. Everyone was between 9 and 70 years old. Over half of the people were male and 46% were female. Most people were White, but 6% were Black or African American and 2% were Asian. Some (8%) were of Hispanic or Latino ethnicity. For most (74%) people, Modeyso was their treatment after their cancer had recurred (come back after treatment) for the first time.

Every two months, people had a magnetic resonance imaging (MRI) scan done to check the status of their cancer. The goal was to see whether people had a complete response or a partial response to Modeyso. 

Modeyso resulted in an overall response rate (number of people who had a complete or partial response to Modeyso) of 20%. One person had a complete response to Modeyso, and nine people had a partial response. Other people had stable disease (n=10), progressive disease (n=18), or an unknown outcome (n=12). 

Your results may differ from what was seen from the analysis described.

Most people had a time to response between 1.9 months and 15.9 months, with the middle value being 8.3 months.

The most common side effects of Modeyso include tiredness, headache, nausea or vomiting, muscle, joint, or bone pain, high liver enzymes, low calcium levels, and low lymphocyte levels. Your health care provider will be monitoring you with blood tests, so they will be aware if there is an abnormal blood test. Make sure to keep all of your appointments with your health care provider to get your blood checked. If low lymphocyte levels or high liver enzymes occur, your health care provider may decide to interrupt your treatment until they return to normal levels.

If you have a headache or muscle, joint, or bone pain, using an over-the-counter (OTC) pain reliever may help. Talk with your health care provider about what OTC product may be best for you.

To help limit nausea and vomiting, you can try simple methods, like eating bland foods such as toast or crackers. Your health care provider may also prescribe medicine to help manage nausea and vomiting.

If your side effects get worse or do not let up, talk with your health care provider.

Your health care provider will regularly check how well Modeyso is working for your cancer by looking at results of tests such as blood tests and MRI scans. Take Modeyso exactly as your health care provider tells you to. Do not change your dose or stop taking Modeyso unless your health care provider tells you to.

There may be cost assistance to help you afford Modeyso. ChimerixCares offers support, including help with financial assistance. Your health care provider can help you get started, or you can call 844-302-2737.