Key takeaways

  • Talvey (talquetamab-tgvs) can cause side effects ranging from mild to serious. More common side effects include fever and cytokine release syndrome.
  • Due to the risk of severe side effects, you’ll typically stay at the hospital for 48 hours after receiving Talvey so that your healthcare team can monitor your condition.
  • If side effects from Talvey become difficult to tolerate, talk with your doctor about coping tips or other treatment options.

Talvey is used to treat relapsed or refractory multiple myeloma in certain adults.

Keep reading to learn about the common, mild, and serious side effects Talvey can cause.

Note: Talvey has boxed warnings. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). For details, see the “Side effects explained” section.

Some people may experience mild to serious side effects during Talvey treatment. Examples of the drug’s commonly reported side effects include:

Mild side effects have been reported with Talvey. These include:

In most cases, these side effects should be temporary. And some may be easily managed. But if you have symptoms that are ongoing or bothersome, talk with your doctor or pharmacist. And do not stop Talvey treatment unless your doctor recommends it.

Talvey may cause mild side effects other than those listed here. See the drug’s prescribing information for details.

Serious side effects have been reported with Talvey. These include:

If you develop serious side effects during Talvey treatment, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Allergic reaction

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

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

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms and can determine whether you should continue Talvey treatment.

If you have symptoms of a severe allergic reaction, such as swelling or difficulty breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to Talvey, they may have you switch to a different treatment.

Get answers to some frequently asked questions about Talvey’s side effects.

Many side effects of Talvey are similar to those of Tecvayli (teclistamab-cqyv). But each drug can cause unique side effects as well.

For example, both Talvey and Tecvayli may cause fever, headache, and diarrhea. Both drugs also have boxed warnings for the risk of cytokine release syndrome and neurologic damage.

But Talvey may also cause severe skin and mouth problems that aren’t known to occur with Tecvayli. And Tecvayli may cause high blood pressure, while Talvey isn’t known to cause this side effect.

For lists of possible side effects of Talvey, see the previous sections. To learn more about Tecvayli’s side effects, see this side effects article. You can also talk with your doctor or pharmacist.

It’s possible. Long-term side effects include those that may start at any time you’re taking a drug, even if you’ve taken it for a long time. It also includes side effects that may not go away even after you stop taking the drug.

For example, cytokine release syndrome and neurologic toxicity were reported in Talvey’s studies. These side effects can lead to organ damage, such as kidney failure or encephalopathy (brain damage). And these effects may cause long-term problems.

Talk with your doctor to learn more about possible side effects of Talvey and how long they may last.

Learn more about some of the side effects Talvey may cause.

Risk of cytokine release syndrome

Talvey has a boxed warning for the risk of cytokine release syndrome (CRS). A boxed warning is the most serious warning from the FDA. CRS was a common side effect reported in studies of Talvey.

CRS happens when cells in the immune system release certain proteins into the blood. In extreme cases, CRS can be life threatening. It may also lead to severe problems such as kidney failure and liver failure.

CRS may cause symptoms such as:

  • fast heart rate
  • fatigue
  • fever
  • headache
  • low blood pressure

Due to this risk, Talvey is only available through a risk evaluation and mitigation strategy (REMS) program. The FDA requires this program to make sure that Talvey is used safely.

What might help

Your doctor will follow certain steps to help prevent CRS. For example, they’ll slowly increase your Talvey dosage over your first three doses. Your doctor will also give you medications before these doses to help prevent CRS. These include:

Your doctor will monitor you for symptoms of CRS whenever you receive a dose of Talvey. You’ll stay in a healthcare facility for at least 48 hours after your first three doses of Talvey.

If you have symptoms of CRS, tell your doctor right away. They may prescribe treatments for your symptoms and will tell you whether it’s safe to continue Talvey treatment.

Risk of neurologic damage

Talvey has a boxed warning for the risk of neurologic damage. A boxed warning is the most serious warning from the FDA. Neurologic damage was a common side effect reported in studies of Talvey.

This side effect occurs when the drug damages your nervous system. In extreme cases, neurologic damage can be life threatening.

Neurologic damage may cause symptoms such as:

  • headache
  • difficulty speaking and understanding speech
  • loss of balance or coordination
  • problems with walking
  • encephalopathy (brain damage)
  • numbness or tingling

Due to this risk, Talvey is only available through a REMS program, which the FDA requires to be sure Talvey is used safely.

What might help

Your doctor will monitor you for symptoms of neurologic damage whenever you receive a dose of Talvey. You’ll stay in a healthcare facility for at least 48 hours after your first three doses of Talvey. It’s also important to avoid driving or operating machinery between the first three doses and for at least 48 hours after your third dose.

If you have symptoms of neurologic damage, tell your doctor right away. They may prescribe treatments for your symptoms and will tell you whether it’s safe to continue Talvey treatment.

Talvey can sometimes cause harmful effects in people with certain conditions. This is known as a drug-condition interaction. Other factors may also affect whether Talvey is a good treatment option for you. Talk with your doctor about your health history before starting this drug. Be sure to tell them if any of the following factors apply to you:

  • current infection
  • previous allergic reaction to Talvey
  • pregnancy
  • breastfeeding
  • alcohol consumption

Disclaimer: While Healthline strives for factual, comprehensive, and current information, this article is not a substitute for a licensed healthcare professional’s expertise. Always consult a doctor before taking or discontinuing any medication. Drug information is subject to change and may not cover all uses, directions, precautions, warnings, interactions, reactions, or adverse effects. The lack of a warning does not guarantee a drug’s safety, effectiveness, or appropriateness for all patients or specific uses. Learn more about our approach to content integrity.