Introduction
Darzalex (daratumumab) is used for treating a blood cancer called multiple myeloma. Darzalex may be used to treat multiple myeloma that has never been treated, is relapsed, meaning the cancer came back after treatment, or that is refractory, meaning it never went away with treatment. Darzalex is usually used along with other medicines but may be used by itself for certain multiple myelomas.
How Does Darzalex Work for Multiple Myeloma?
Darzalex is a type of medicine called a monoclonal antibody that is also known as a targeted therapy or an immunotherapy. It works by targeting a specific protein called CD38 that can be on the surface of blood and bone marrow cells, including the ones that cause multiple myeloma. CD38 is expressed much more on the cells that cause multiple myeloma than healthy cells. Darzalex attaches itself to the CD38 protein and prevents the cell from growing, which makes it eventually die.
How Do I Use Darzalex?
Doses of Darzalex are given by an IV through a blood vessel in your arm over a period of time. Your dose will be given by a health care provider. Your dosing schedule, or how often you will use Darzalex, will depend on your specific multiple myeloma details and if you are using Darzalex alone or along with other medicines. You can expect that each IV will last several hours. You will receive these doses in a hospital, clinic, or infusion center. Your health care provider will use your weight to calculate the exact amount of Darzalex that you will need.
Depending on the specifics of your multiple myeloma, you may continue using Darzalex for as long as possible, meaning you will use it until your cancer progresses or you have side effects that make it not safe for you to use. You may also only use Darzalex for a certain time. If you have certain side effects, your health care provider may pause your doses of Darzalex. In some cases, they may need to have you stop using Darzalex completely.
Talk with your health care provider about how long you can expect to use Darzalex. They can also talk with you about how often you will use Darzalex and how long you can expect your IVs to last. If you miss an appointment for a Darzalex IV, contact your health care provider right away to reschedule your appointment to make sure your treatment is effective.
How Well Does It Treat Multiple Myeloma?
Darzalex was studied across multiple clinical trials to make sure it was effective for treating multiple myeloma in all of the indications listed above. An example of one of these trials is the MAIA trial, which had people use Darzalex along with other medicines (lenalidomide and dexamethasone). These people had newly diagnosed multiple myeloma, meaning it had not received any prior treatments, and they were not eligible for a stem cell transplant. A total of 737 people were in the clinical trial, with 369 using lenalidomide and dexamethasone only and 368 people using Darzalex with lenalidomide and dexamethasone. They were followed to see how long it took for their multiple myeloma to progress, meaning that the cancer got worse. This measurement is called progression-free survival.
The ages of people in the study ranged from 45 to 90 years. The median age was 73, and 44% were 75 or older. Fifty-two percent of the people studied were male. And 92% were White, 4% Black or African American, and 1% Asian. Three percent reported an ethnicity of Hispanic or Latino.
After following at least half of the people a little over 5 years (64 months), the median progression-free survival for the people who used Darzalex was 61.9 months, compared to 34.4 months for the people who only used lenalidomide and dexamethasone. This means that half of the people who used Darzalex did not have their cancer progress, or get worse, for at least 61.9 months. It’s important to note that the true median progression-free survival in the study has not been reached for the people who used Darzalex because they are still being followed and not having their cancer get worse. Only half of the people had been followed for at least 64 months, meaning that all of the people will continue to be followed until their cancer gets worse. This means that the median progression-free-survival has the potential to become longer than 61.9 months for the people who use Darzalex.
Talk with your health care provider about your specific multiple myeloma and get information about the study that tested Darzalex in multiple myeloma like yours. They will be able to talk you through the study specifics and how people in the study had their cancer respond to Darzalex.
How Will My Progress Be Monitored?
Darzalex will start working as soon as you receive your first IV. Your health care provider will do regular bloodwork to monitor how Darzalex is working in your body and treating your cancer. These tests will monitor your blood counts such as white blood cells, neutrophils, and platelets, so that your health care provider knows that you can continue to use Darzalex safely. If you have certain side effects, such as frequent infections, your health care provider may do more tests to make sure it is safe for you to continue to use Darzalex.
How Can I Prevent and Manage Side Effects?
Side effects are common with medicines that treat cancer, including Darzalex. It is important to tell your health care provider about any side effects you have during your Darzalex treatment or after it’s done. They can help to determine if your side effects are serious or provide more information to help you manage the side effects.
Your health care provider will usually instruct you to take certain medicines before and after your IV to help prevent common side effects, such as infusion-related reactions like itching, a rash, and nausea. It is important to follow their instructions. Besides taking medicines before and after your IV, you can ask your health care provider what else you can do to prevent or treat common side effects. For example, you can help prevent and treat nausea, vomiting, and diarrhea by eating bland foods and having multiple small meals throughout the day instead of three large meals. They may also recommend you keep certain over-the-counter medicines on hand to treat common side effects like diarrhea. They will also tell you how to watch for severe side effects, such as shortness of breath and heart problems, and what to do if you have these side effects.
Your health care provider will have you do bloodwork regularly while you are using Darzalex. It is important to attend all of your appointments for bloodwork so that your health care provider can make sure Darzalex is safe for you. These tests will look at your blood cell counts to make sure it is safe for you to continue to use the medicine. This is because Darzalex can cause low blood cell counts, such as low platelets (thrombocytopenia) and low white blood cells (neutropenia). If not treated, low blood cell counts can cause serious infections or hurt your body’s ability to clot blood. This can be dangerous and even life-threatening.
If you have certain side effects while you use Darzalex, your health care provider may need to pause your doses or even stop your medicine altogether. This will depend on the side effect you have, how severe it is, and what treatment it needs. If your Darzalex needs to be paused, it is possible that your health care provider will restart the medication once your side effect is treated and gets better.
What Are Other Unique Considerations to Be Aware Of?
Darzalex can cause infusion-related reactions. These are considered common reactions, and for some people, they can be serious and even life-threatening. Your health care provider will monitor you closely for infusion-related reactions while you get your IV infusions. Most of the reactions happened within 4 hours of finishing the Darzalex IV. In earlier clinical trials, some reactions did happen up to 48 hours after the IV. It is important to tell your health care provider right away if you have any of the following symptoms of an infusion-related reaction:
- Shortness of breath or trouble breathing
- Dizziness, lightheadedness, or a feeling like you are going to pass out
- Coughing
- Wheezing
- A feeling that your throat is tight or irritated
- Runny or stuffy nose
- Headache
- Itching
- Eye pain
- Nausea or vomiting
- Chills or a fever
- Chest pain or discomfort
- Blurred vision
- Heart beating faster than usual
It’s possible that Darzalex can affect the way blood tests work for your blood type. These changes can last for up to 6 months after your last dose of Darzalex. Make sure to tell any health care provider that is treating you that you are using Darzalex. This is important for them to know in case you need a blood transfusion.
Darzalex can harm an unborn baby. For people who were assigned female at birth, it is important to make sure you are not pregnant before starting Darzalex. Your health care provider will talk with you about using effective birth control while you use Darzalex and for at least 3 months after your last dose. If you were assigned male at birth and have a partner who can become pregnant, it is important to use effective birth control to prevent pregnancy. You will also not be able to donate sperm while using Darzalex. This is because of the other medicines that Darzalex is used with. Talk with your health care provider if this is a concern for you.
If you have a history of a hereditary fructose intolerance, you should not use Darzalex. This is because it has sorbitol and people who have hereditary fructose intolerance cannot break it down, which can increase the risk of serious side effects.
Is There Any Cost Assistance Available?
The maker of Darzalex has a program to provide financial assistance for certain people and may be able to offer coupons or savings for Darzalex.
