Rytelo is a brand-name intravenous (IV) infusion that’s prescribed for a certain group of blood cancers. Rytelo contains the active ingredient imetelstat.

Specifically, the Food and Drug Administration (FDA) has approved Rytelo to treat myelodysplastic syndromes (MDS) in certain adults.

Drug details

You’ll find key information about Rytelo below.

  • Drug class: telomerase inhibitor
  • Drug form: powder mixed with liquid to form a solution to be given as an IV infusion
  • Generic available? no
  • Prescription required? yes
  • Controlled substance? no
  • Year of FDA approval: 2024

Rytelo is available only as a brand-name medication. It’s not currently available in generic form.

A generic drug is an exact copy of the active ingredient in a brand-name medication. Generics usually cost less than brand-name drugs.

The Rytelo dosage your doctor prescribes will depend on certain factors. These include:

  • any side effects you may have
  • your body weight in kilograms (kg)

For reference, 1 kg is about 2.2 pounds (lb).

The following information describes dosages that are commonly used or recommended. However, your doctor will determine the best dosage to fit your needs.

Drug form and strengths

Rytelo comes as a powder in single-use vials. A healthcare professional mixes the powder with liquid to form a solution.

Rytelo is available in two strengths: 47 milligrams (mg) and 188 mg.

Dosage for MDS

Rytelo is prescribed to treat myelodysplastic syndromes (MDS) in certain adults. For details, see the “Rytelo uses” section.

The typical dosage of Rytelo is 7.1 mg per kg of body weight every 4 weeks. For example, a person who weighs 80 kg (about 176 lb) would receive 568 mg every 4 weeks.

Your doctor will advise you on how many doses of Rytelo you’ll receive.

How it’s given

A healthcare professional will give Rytelo as an IV infusion (an injection into a vein that’s given over time). Each infusion is typically given over 2 hours. You’ll receive Rytelo in a clinic or hospital.

To help reduce your risk of certain side effects, your doctor may give you other medications 30 minutes before the infusion. These may include:

After each infusion, you’ll likely stay in the facility where you received the drug for at least 1 hour. This allows your doctor to monitor you closely for serious side effects.

If you have other questions about receiving Rytelo, talk with your doctor.

About receiving Rytelo

Below you’ll find information about key dosage issues.

  • When to receive: You’ll receive one infusion of Rytelo every 4 weeks.
  • If you miss a dose: If you miss an appointment for your Rytelo infusion, call the clinic or hospital right away to reschedule.
  • Length of use: The length of time you’ll receive Rytelo depends on certain factors, including how your condition responds to the drug and whether you have any side effects. Your doctor will recommend how long you’ll receive Rytelo.
  • Length of time to work: Rytelo starts to work after your first dose. Your doctor will monitor your condition to determine how well the drug is working. They’ll advise you on how your condition is responding to Rytelo.

Rytelo can cause mild or serious side effects. The following lists contain some of the key side effects that may occur during treatment with Rytelo. These lists do not include all possible side effects.

For more information about the possible side effects of Rytelo, talk with your doctor or pharmacist. They can give you tips on how to manage any side effects that may be concerning or bothersome.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. Sharing your experience helps make medications safer for everyone by giving doctors and researchers more information about how the drug works in real life. If you develop a side effect during Rytelo treatment and want to tell the FDA about it, visit MedWatch or call 800-FDA-1088.

Mild side effects

Below is a partial list of mild side effects of Rytelo. To learn about other mild side effects, talk with your doctor or pharmacist or view Rytelo’s prescribing information.

Mild side effects of Rytelo can include:

  • fatigue
  • headache
  • muscle or joint pain
  • prolonged blood clotting time

Most of these side effects may go away within a few days to a couple of weeks. However, if they become more severe or don’t go away, talk with your doctor or pharmacist.

Serious side effects

Serious side effects from Rytelo aren’t common, but they can occur. Call your doctor right away if you have serious side effects. Call 911 or your local emergency number if your symptoms feel life threatening or you think you’re having a medical emergency.

Serious side effects and their symptoms can include:

ALLERGIC REACTION

For some people, Rytelo can cause an allergic reaction. But this side effect wasn’t reported in the drug’s clinical trials.

In general, symptoms of allergic reaction can be mild or serious.

Ways to manage

For mild allergic reaction symptoms, such as a mild rash, call your doctor right away. They may recommend treatments to help manage your symptoms. They’ll also let you know whether you should keep receiving doses of the medication.

For severe allergic reaction symptoms, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms require immediate medical care because they can become life threatening. If you’ve had a serious allergic reaction to Rytelo, your doctor may recommend a different medication instead.

The Food and Drug Administration (FDA) approves prescription drugs such as Rytelo to treat certain conditions.

Rytelo for MDS

Rytelo is approved to treat myelodysplastic syndromes (MDS) in certain adults.

MDS is a group of blood cancers that affect how the bone marrow makes blood cells. MDS may not cause symptoms but can be detected with a blood test that shows low levels of red blood cells, white blood cells, or platelets.

MDS could develop into another blood cancer called acute myeloid leukemia (AML). Rytelo can be prescribed for adults with MDS who have a lower risk of developing AML and meet the following criteria:

  • have anemia (low red blood cell levels) and need blood transfusions of at least 4 units over 8 weeks
  • have not met the criteria to use erythropoiesis-stimulating agents (ESAs), or have used ESAs that did not work or have stopped working

To learn more about Rytelo for MDS, talk with your doctor.

Rytelo and children

Rytelo is not FDA approved for use in children. It’s not known for certain whether the drug is safe or effective for children.

Rytelo is not known to interact with other medications, herbs, supplements, foods, or alcohol. The manufacturer did not list any interactions in the drug’s prescribing information.

However, this doesn’t mean that interactions won’t be recognized in the future. For example, new drugs could be approved that interact with Rytelo.

Before starting Rytelo treatment, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also, tell them about any vitamins, herbs, and supplements you take. Sharing this information can help you avoid potential interactions.

If you have questions about drug interactions that may affect you, talk with your doctor or pharmacist.

As with all medications, the cost of Rytelo can vary. The actual price you’ll pay depends on your insurance plan and your location.

Financial and insurance assistance: If you need financial support to pay for Rytelo or need help understanding your insurance coverage, help is available.

A program called REACH4RYTELO is available for Rytelo. For more information and to find out whether you’re eligible for support, visit the program website.

Generic version: Rytelo is not available in a generic form. A generic drug is an exact copy of the active ingredient in a brand-name medication. Generics tend to cost less than brand-name drugs.

Learn more about saving money on prescriptions.

Other drugs are available that can treat myelodysplastic syndromes (MDS). Some may be a better fit for you than others. If you’re interested in finding an alternative to Rytelo, talk with your doctor. They can tell you about other medications that may work well for you.

Examples of drugs that are alternatives to Rytelo include:

If you can become pregnant, consider the following information about pregnancy, fertility, birth control, and breastfeeding.

Rytelo and pregnancy

It’s not known whether Rytelo is safe to receive during pregnancy. Animal studies suggest that the drug may cause harm to a fetus. However, animal studies don’t always predict what will happen in humans.

If you’re planning a pregnancy or can become pregnant, talk with your doctor before receiving this medication. They’ll likely give you a pregnancy test before you start Rytelo treatment.

Rytelo and fertility

In animal studies, Rytelo temporarily decreased female fertility (the ability to conceive). However, animal studies don’t always predict what will happen in humans.

Before starting Rytelo treatment, talk with your doctor about the drug’s possible effects on fertility. They can recommend whether Rytelo is the right treatment option.

Note: Sex and gender exist on spectrums. Use of the terms “female” and “male” in this article refers to sex assigned at birth.

Rytelo and birth control

It’s not known whether Rytelo is safe to receive during pregnancy. If you’re sexually active and you or your partner can become pregnant, talk with your doctor about your birth control needs during Rytelo treatment.

For females receiving Rytelo

Doctors may advise females who can become pregnant to use birth control during Rytelo treatment and for at least 1 week after the final dose. If you’re a female receiving Rytelo, talk with your doctor about your birth control needs.

For males receiving Rytelo

The manufacturer of Rytelo has not given specific recommendations about birth control use in males during treatment. If you’re a male receiving Rytelo, talk with your doctor about your birth control needs.

Rytelo and breastfeeding

It’s not known whether Rytelo is safe to receive while breastfeeding. To be safe, it’s recommended that you avoid breastfeeding during Rytelo treatment and for at least 1 week after your final dose.

If you’re currently breastfeeding or planning to do so, talk with your doctor before starting Rytelo treatment.

Rytelo is used to treat myelodysplastic syndromes (MDS) in certain adults. MDS is a group of blood cancers that affect how the bone marrow makes blood cells.

Rytelo’s mechanism of action (how it works) is to target a specific enzyme (a type of protein) that helps cancer cells grow and divide. By blocking this enzyme, Rytelo treats MDS and helps slow the growth of cancer.

If you have other questions about how Rytelo works, talk with your doctor or pharmacist.

Here are answers to some frequently asked questions about Rytelo.

How does Rytelo compare to Reblozyl?

Rytelo and Reblozyl are both used to treat certain types of blood disorders, but they have important differences.

Rytelo is used to treat myelodysplastic syndromes (MDS) in certain adults. Reblozyl is used to treat anemia (low red blood cell levels) related to specific conditions, including MDS. Reblozyl has other approved uses as well.

Rytelo and Reblozyl have different active ingredients and are given in different ways. Rytelo contains imetelstat, while Reblozyl contains luspatercept-aamt. Rytelo is given as an IV infusion, but Reblozyl is given as a subcutaneous injection.

Your doctor can recommend whether Rytelo or Reblozyl is the right treatment option for your condition. They can provide more information about how these drugs compare and which one may be better for you.

Is Rytelo a chemotherapy drug?

No, Rytelo is not a chemotherapy drug.

Chemotherapy drugs work by destroying all cells in the body that are quickly multiplying. Cancer cells typically multiply more quickly than healthy cells. However, chemotherapy can still affect healthy cells in the body. This leads to many of the side effects of chemotherapy.

Rytelo works by targeting a specific enzyme (a type of protein) that helps cancer cells grow and divide.

For more information about how Rytelo compares with chemotherapy, talk with your doctor.

Before receiving Rytelo, discuss your health history with your doctor. Rytelo may not be right for you if you have certain medical conditions or other factors affecting your health. Be sure to talk with your doctor if any of the following apply to you:

Note: For more information about the potential negative effects of Rytelo, see the “Rytelo side effects” section.

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.