Ado-Trastuzumab Emtansine (Intravenous)

A treatment for HER2-positive metastatic breast cancer, Ado-Trastuzumab Emtansine interferes with the growth of proteins produced by some breast tumors.


Ado-Trastuzumab Emtansine interferes with the growth of HER2 protein, which is produced by some breast tumors. As a result of the use of this medication, the tumor cells are then able to be more efficiently destroyed by the patient's body. Therefore, this medication is used as a treatment for this form of breast cancer.

Ado-Trastuzumab Emtansine is an intravenous medication that is used as a method to treat HER2-positive metastatic breast cancer, which is a cancer that has spread to other parts of the body. It is primarily used with patients who have already received other medicines that they have not reacted positively to.

The drug is available in a powder for solution form that can then be used for injection and is to be administered solely by or under the immediate supervision of your doctor to ensure safety and correct usage. Ado-Trastuzumab Emtansine is known under US brand name Kadcyla.

Ado-Trastuzumab Emtansine can cause many side effects due to the nature of the medication and is not recommended for pregnant patients, due to possible risks to the fetus. The exception to this is when the pregnant patient is in a life-threatening situation in which the usage of this drug may outweigh the potential risk.

Conditions treated

  • HER2-positive, metastatic breast cancer for patients who have previously received Trastuzumab and a tisane to no effect

Type of medicine

  • Monoclonal antibody combined with a microtubular inhibitor

Side effects

As well as the intended and needed effects of the drug, Ado-Trastuzumab Emtansine can cause other side effects due to the nature of the medication. Although not all, or even any, of these side effects, may occur during treatment with this drug, if they do occur, the patient may require medical attention as a result of them.

Check with a doctor or nurse immediately if any of the following side effects occur:

More common

  • black, tarry stools
  • bladder pain
  • bleeding gums
  • bloating or swelling of the face, arms, hands, lower legs, or feet
  • bloody or cloudy urine
  • blurred vision
  • burning, numbness, tingling, or painful sensations
  • chills
  • convulsions
  • cough
  • decreased urine
  • difficult or labored breathing
  • difficult, burning, or painful urination
  • dizziness
  • dry mouth
  • fever
  • frequent urge to urinate
  • headache
  • increased thirst
  • irregular heartbeat
  • loss of appetite
  • lower back or side pain
  • mood changes
  • muscle pain or cramps
  • nausea or vomiting
  • nervousness
  • nosebleeds
  • numbness or tingling in the hands, feet, or lips
  • pale skin
  • pinpoint red spots on the skin
  • pounding in the ears
  • rapid weight gain
  • slow or fast heartbeat
  • sore throat
  • tightness in the chest
  • troubled breathing with exertion
  • ulcers, sores, or white spots in the mouth
  • unsteadiness or awkwardness
  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • unusual weight gain or loss
  • weakness in the arms, hands, legs, or feet

Less common

  • chest pain
  • dilated neck veins
  • extreme fatigue
  • general feeling of discomfort or illness
  • irregular breathing
  • irregular heartbeat
  • skin rash
  • thickening of bronchial secretions


  • dark-colored urine
  • general feeling of tiredness or weakness
  • light-colored stools
  • stomach bloating or pain
  • vomiting blood
  • yellow eyes or skin

Incidence not known

  • abdominal or stomach tenderness
  • itching

In addition to side effects that may require some form of medical attention, Ado-Trastuzumab Emtansine can also cause side effects that may be a result of the body adjusting the medication and will become less prevalent or go away over time.

Additional medication may be provided to prevent or help any of the following side effects, but they should not otherwise need medical intervention unless they become uncomfortable or worse over time:

More common

  • acid or sour stomach
  • belching
  • change in taste
  • constipation
  • diarrhea
  • difficulty with moving
  • heartburn
  • indigestion
  • lack or loss of strength
  • loss of taste
  • muscle pain or stiffness
  • pain in the joints
  • stomach discomfort or upset
  • swelling or inflammation of the mouth
  • trouble sleeping

Less common

  • burning, dry, or itching eyes
  • discharge or excessive tearing
  • redness, pain, or swelling of the eye, eyelid, or inner lining of the eyelid

If any side effects, in addition to those listed above, are experienced, or you experience anything else out of the ordinary following the use of Ado-Trastuzumab Emtansine for the treatment of HER2-positive metastatic breast cancer, medical attention should be sought immediately to ensure your wellbeing.

Side effects caused by Ado-Trastuzumab Emtansine are often predictable regarding their onset, duration, and severity, and often any side effects will improve after therapy is complete.


A doctor, or other trained health professional, will administer this medicine to the patient in a hospital or a cancer treatment center. This drug is given through a needle placed in a vein. It is usually given once every three weeks.

The amount of Ado-Trastuzumab Emtansine administered depends upon many factors, including the weight, general health or other health problems of the patient, and the type of cancer or condition being treated. A trained and qualified doctor will determine your dose and schedule.

Due to the therapy-based administration of Ado-Trastuzumab Emtansine, there is no requirement for this drug to be taken outside the above circumstances. However, should the patient receive a higher dosage than anticipated or receive Ado-Trastuzumab Emtansine outside the recommended circumstances, resulting in side effects or other medical issues, either 911 or the FDA (1-800-FDA-1088) should be contacted to record these issues.


Ado-Trastuzumab Emtansine can interact with other drugs within the human body, which can change the way it affects the body and may make it ineffective, or even harmful. Patients and physicians should keep an up to date list of all medications and diagnostic drugs currently in use by the patient to prevent any issues with drug interaction that may have a negative effect.

It is of great importance that the patient's doctor is made aware of every drug within the patient's system, from long-term medication to readily available drugs, and that the patient makes their doctor aware of their recent and current medication usage. This ensures treatment is effective and less likely to cause harm.

Although certain medicines should not be used in conjunction with Ado-Trastuzumab Emtansine, when permitted by medical professionals, the patient may use different medicines together, even if an interaction might occur. In these cases, your doctor may want to alter the dose given; other precautions may also be necessary.

Using Ado-Trastuzumab Emtansine with any of the listed drugs below is not usually recommended, but may be required in some cases, as determined by a medical professional. If both medicines are prescribed together, a doctor may wish to alter the dose or how often the patient uses one or both of the medicines, depending on the patient's needs.

  • Atazanavir
  • Boceprevir
  • Clarithromycin
  • Cobicistat
  • Conivaptan
  • Idelalisib
  • Indinavir
  • Itraconazole
  • Ketoconazole
  • Lopinavir
  • Nefazodone
  • Nelfinavir
  • Posaconazole
  • Ritonavir
  • Saquinavir
  • Telaprevir
  • Telithromycin
  • Tipranavir
  • Voriconazole

Certain drugs should not be used at or around the time of eating either all or certain types of food, or as interactions may occur. Using alcohol, tobacco or street drugs with certain medications may also cause interactions to occur. The below interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using Ado-Trastuzumab Emtansine with any of the following is not generally recommended, although it may not be avoidable for some people. Ordinarily, if used in conjunction, a medical professional may choose to change the dose or how often you use this medicine, or offer special instructions about the use of food, alcohol, tobacco and other substances.

Grapefruit juice

The presence of other pre-existing medical issues or problems may affect your use of this medication. Ensure a medical professional is informed if you have any other existing medical problems, especially:


When using Ado-Trastuzumab Emtansine, it is critical that the medical professional who administers this drug checks the progress of the patient at regular intervals. This will allow a doctor or professional to see if the medication is working as it should, and to decide if you should continue to receive it. Blood tests may be needed to check for unwanted or concerning side effects.

Using this drug while you are pregnant can cause very serious birth defects. Patients using this treatment are advised to utilize an effective form of birth control to prevent them from getting pregnant during treatment, and for seven months following the last dose. In addition, there is a potential for this medicine to cause birth defects or issues if the father is undergoing treatment when his sexual partner becomes pregnant. If you think you have become pregnant while using Ado-Trastuzumab Emtansine, tell your doctor right away.

Patients should notify their doctor immediately if they have pain or tenderness in the upper right stomach, dark urine, pale stools, loss of appetite, nausea, vomiting, or yellow eyes or skin. These could be symptoms of a serious liver problem.

In addition to the above side effects directly related to Ado-Trastuzumab Emtansine, this medicine can also temporarily lower the amount of white blood cells in your blood, increasing your chance of getting an infection. This drug can also lower the number of platelets, which are necessary for proper blood clotting within the body. If this occurs, there are certain precautions that can be taken, especially when your blood count is low, in order to reduce the risk of infection or bleeding:

  • If you can, avoid people with infections. Check with your doctor immediately if you think you are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.
  • Check with your doctor immediately if you notice any unusual bleeding or bruising, black or tarry stools, blood in the urine or stools, or pinpoint red spots on your skin.
  • Be careful when using a regular toothbrush, dental floss, or toothpick. Your medical doctor, dentist, or nurse may recommend other ways to clean your teeth and gums. Check with your medical doctor before having any dental work done.
  • Do not touch your eyes or the inside of your nose unless you have just washed your hands and have not touched anything else in the meantime.
  • Be careful not to cut yourself when you are using sharp objects, such as a safety razor or fingernail or toenail cutters.
  • Avoid contact sports or other situations where bruising or injury could occur.

This medicine may cause heart failure. A medical professional may test the patient's heart before and during treatment. A doctor should be contacted right away if the patient experiences chest pain, trouble breathing, increased coughing, rapid weight gain or swelling in the ankles or legs. These could be symptoms of heart failure.

Ado-Trastuzumab Emtansine can also cause a serious infusion reaction. This reaction can be life-threatening and requires immediate medical attention. Tell a doctor or professional right away if you are experiencing fever, chest pain, chills, fast or uneven heartbeat, lightheadedness or dizziness, fainting, headache, rash, trouble breathing, or weakness while you receive this treatment or after the infusion.


KADCYLA, the US name for Ado-Trastuzumab Emtansine, is supplied as a sterile powder for concentrate and comes in two vial types. Vials will reconstitute to 20 mg/mL.

Vials of Ado-Trastuzumab Emtansine should be stored in a refrigerator at 2°C-8°C (36°F-46°F) until the time of use. Calculated information on dosage for body weight is available from KADCYLA.

Reconstituted vials with SWFI and diluted KADCYLA infusion solution are recommended to be used immediately. If that is not possible, the drug can be stored in a refrigerator at 2°C-8°C (36°F-46°F) up to 24 hours prior to use. It is imperative to retain the quality of the medications that the substance is not frozen or shaken.

The storage time suggested for KADCYLA infusion solution medication is in addition to the time allowed for the reconstituted vials.

Any unused solution should be discarded within 24 hours.


Ado-Trastuzumab Emtansine is an intravenous treatment used in the treatment of HER2-positive metastatic breast cancer. It is used primarily with patients who have undergone other treatments with little to no response.

Ado-Trastuzumab Emtansine acts as a monoclonal antibody. This means it targets the surface of the cells HER2 on the cancer cell, working to interfere with HER2 and causing cancer cell death, in order to allow tumor cells to be destroyed. Ado-Trastuzumab Emtansine combines the HER2 targeted actions of Trastuzumab with the microtubule inhibitor DM1.

A wide range of side effects are associated with Ado-Trastuzumab Emtansine, due to the nature of the medication, including, but not limited to, heart failure, liver disease and birth defects for pregnant women. All of these factors, as well as the others listed within the side effects section, should be considered before consenting to this treatment.

Last Reviewed:
December 10, 2017
Last Updated:
April 04, 2018