Teclistamab-cqyv (Tecvayli™)

Author: Marisa Healy, BSN, RN
Content Contributor: Oxana Megherea, PharmD - Oncology Clinical Pharmacy Specialist
Last Reviewed: February 26, 2024

Pronounce: tek-LIS-tuh-mab

Classification: Bispecific B-cell maturation antigen (BCMA)-directed CD3 T-cell engager

About: Teclistamab-cqyv (Tecvayli™)

This medication is a bispecific BCMA-directed CD3 T-cell engager used to treat some forms of multiple myeloma (MM). Teclistamab-cqyv activates your T-cells (part of your immune system) by connecting the CD3 antigen (found on T-cells) with BCMA, which is found on the surface of MM cells. The redirected T-cells kill MM cells.

Teclistamab-cqyv is given as a subcutaneous (SubQ, under the skin) injection. The dosage of this medication depends on your body size. You will receive the “step-up dosing schedule” for three doses in the hospital. Next, you will receive your weekly treatment dose in an outpatient facility 7 days after finishing the step-up dosing schedule.

You will be given “pre-medications” before each step-up dose of teclistamab-cqyv. These may include a steroid, a histamine-1 (H1) receptor antagonist (such as diphenhydramine/Benadryl), and an antipyretic (such as acetaminophen/Tylenol). Some patients will need these pre-medications with every dose depending on adverse reactions.

You will need to stay in the hospital for at least 2 days once you have finished the step-up schedule (first 3 doses) of the injection so that your care team can monitor your reaction.


Teclistamab-cqyv is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) called the TECVAYLI REMS. This program is in place due to the risks of cytokine release syndrome (CRS) and neurologic toxicity, including immune effector cell–associated neurotoxicity syndrome (ICANS). Prescribers and pharmacies/healthcare settings must be certified with the program by enrolling and completing training. Prescribers must counsel patients on CRS and neurotoxicity and complete and provide patients with a Patient Wallet Card to carry with them at all times.

Possible Side Effects of Teclistamab-cqyv

There are a number of things you can do to manage the side effects of teclistamab-cqyv. Talk to your care team about these recommendations. They can help you decide what will work best for you. These are some of the most common or important side effects:

Cytokine Release Syndrome (CRS)

Cytokine release syndrome (CRS) can occur. T-cells are activated by this medication, causing them to release many cytokines. The cytokines cause an inflammatory response in the body. This reaction, if left untreated, can be very dangerous. Signs and symptoms may be fever, having a hard time breathing, chills, low blood pressure, fast heart rate, headache, and higher levels of liver enzymes in your blood. Your care team will monitor you closely for CRS while you are on therapy with teclistamab-cqyv. You should call your provider right away if you have any signs or symptoms of CRS so that treatment can be started.

Neurologic Toxicity including ICANS

Neurological (brain) toxicities, such as aphasia (being unable to speak or understand speech), a change in mental status, and seizures have happened in patients who received this medication. Your care team will be monitoring you very closely for any changes in your mental status.

Low White Blood Cell Count (Leukopenia or Neutropenia)

This medication can cause life threatening infections, with or without a decrease in white blood cell counts. Common infections with this medication are an upper respiratory infection (affects your nose, throat, and airway) and pneumonia (lung infection).

White blood cells (WBC) are important for fighting infection. While receiving treatment, your WBC count can drop, putting you at a higher risk of getting an infection. You should let your doctor or nurse know right away if you have a fever (temperature greater than 100.4°F or 38°C), sore throat or cold, shortness of breath, cough, burning with urination, or a sore that doesn't heal.
Tips to preventing infection:

  • Washing hands, both yours and your visitors, is the best way to prevent the spread of infection.
  • Avoid large crowds and people who are sick (i.e.: those who have a cold, fever or cough or live with someone with these symptoms).
  • When working in your yard, wear protective clothing including long pants and gloves.
  • Do not handle pet waste.
  • Keep all cuts or scratches clean.
  • Shower or bathe daily and perform frequent mouth care.
  • Do not cut cuticles or ingrown nails. You may wear nail polish, but not fake nails.
  • Ask your oncology care team before scheduling dental appointments or procedures.
  • Ask your oncology care team before you, or someone you live with, has any vaccinations.

Low Platelet Count (Thrombocytopenia)

Platelets help your blood clot, so when the count is low you are at a higher risk of bleeding. Let your oncology care team know if you have any excess bruising or bleeding, including nose bleeds, bleeding gums or blood in your urine or stool. If the platelet count becomes too low, you may receive a transfusion of platelets.

  • Do not use a razor (an electric razor is fine).
  • Avoid contact sports and activities that can result in injury or bleeding.
  • Do not take aspirin (salicylic acid), non-steroidal, anti-inflammatory medications (NSAIDs) such as Motrin/Advil (ibuprofen), Aleve (naproxen), Celebrex (celecoxib) etc. as these can all increase the risk of bleeding. Please consult with your healthcare team regarding use of these agents and all over the counter medications/supplements while on therapy.
  • Do not floss or use toothpicks and use a soft-bristle toothbrush to brush your teeth.

Liver Toxicity

This medication can cause liver toxicity, which your oncology care team may monitor for using blood tests called liver function tests. Notify your healthcare provider if you notice yellowing of the skin or eyes, your urine appears dark or brown, or you have pain in your abdomen (belly), as these can be signs of liver toxicity.

Low Red Blood Cell Count (Anemia)

Your red blood cells are responsible for carrying oxygen to the tissues in your body. When the red cell count is low, you may feel tired or weak. You should let your oncology care team know if you experience any shortness of breath, difficulty breathing or pain in your chest. If the count gets too low, you may receive a blood transfusion.

Muscle or Joint Pain/Aches

Your healthcare provider can recommend medications and other strategies to help relieve pain.

Electrolyte Abnormalities

This medication can affect the normal levels of electrolytes (sodium, phosphorus, calcium, etc.) in your body. Your levels will be monitored using blood tests. If your levels become too low, your care team may prescribe specific electrolytes to be given by IV or taken by mouth. Do not take any supplements without first consulting with your care team.

Injection Site Reactions

You may have pain, redness, or swelling at the site of the injection. There is also a chance of allergic reaction with this medication. During the injection and afterward, if you have a hard time breathing or swallowing, facial swelling, have chest pain, "racing" heart, cough or wheezing, develop flushing, hives or rash, nausea or vomiting, lightheadedness, headache, fever, chills, or shakes, let your nurse or care team know right away. Additional medications may be given to help you feel better.


Fatigue is very common during cancer treatment and is an overwhelming feeling of exhaustion that is not usually relieved by rest. While on cancer treatment, and for a period after, you may need to adjust your schedule to manage fatigue. Plan times to rest during the day and conserve energy for more important activities. Exercise can help combat fatigue; a simple daily walk with a friend can help. Talk to your healthcare team for helpful tips on dealing with this side effect.

Kidney Problems

This medication can cause kidney problems, including an increased creatinine level, which your oncology care team may monitor for using blood tests. Notify your healthcare provider if you notice decreased urine output, blood in the urine, swelling in the ankles, or loss of appetite.

Nausea and/or Vomiting

Talk to your oncology care team so they can prescribe medications to help you manage nausea and vomiting. In addition, dietary changes may help. Avoid things that may worsen the symptoms, such as heavy or greasy/fatty, spicy or acidic foods (lemons, tomatoes, oranges). Try saltines or ginger ale to lesson symptoms.
Call your oncology care team if you are unable to keep fluids down for more than 12 hours or if you feel lightheaded or dizzy at any time.


Your oncology care team can recommend medications to relieve diarrhea. Also, try eating low-fiber, bland foods, such as white rice and boiled or baked chicken. Avoid raw fruits, vegetables, whole grain breads, cereals and seeds. Soluble fiber is found in some foods and absorbs fluid, which can help relieve diarrhea. Foods high in soluble fiber include: applesauce, bananas (ripe), canned fruit, orange sections, boiled potatoes, white rice, products made with white flour, oatmeal, cream of rice, cream of wheat, and farina. Drink 8-10 glasses of non-alcoholic, un-caffeinated fluid a day to prevent dehydration.

Reproductive Concerns

Exposure of an unborn child to this medication could cause birth defects, so you should not become pregnant while on this medication. Effective birth control is necessary for females during treatment and for at least 5 months after the last dose. Even if your menstrual cycle stops, you could still be fertile and conceive. You should not breastfeed during treatment and for at least 5 months after the last dose.