What is chemotherapy and what other medicines are used to treat multiple myeloma? 

Chemotherapy (chemo) uses strong medicines to kill cancer cells. The medicines attack and kill cells that grow quickly, like cancer cells. Some normal cells also grow quickly. Because of this, chemo can also harm those cells. This can cause side effects.

Immunomodulatory medicines (IMiDs) help the immune system kill cancer cells. They also keep tumors from growing the new blood vessels they need to feed the cancer cells.

Targeted therapy medicines  are target genes and proteins found mostly in the cancer cells. This way, they kill cancer cells but cause less damage to normal cells than chemo.

Corticosteroids (steroids) are used to reduce the number of myeloma cells and help relieve pain and pressure caused by tumors. They can also reduce nausea and vomiting.

Bone-modifying medicines are almost always part of multiple myeloma treatment. They help keep the bones strong and reduce the risk of breaking.

When are these medicines used for multiple myeloma? 

A combination of medicines that work in different ways is the main treatment for multiple myeloma. The types of medicines you get will depend mainly on:

• How quickly the myeloma is likely to grow and cause problems

• Whether or not you might be able to have a stem cell transplant

• Gene and protein changes found on or in the myeloma cells

• How well your kidneys are working

• The goal of treatment

• Your age and overall health

• Concerns you have about side effects

• What treatments you’ve had in the past

• Your preferences

Two or 3 of these medicines may be recommended:

• As the first treatment for myeloma

• As part of a stem cell transplant

• As a later treatment if the first treatment stops working or if the myeloma starts growing again after treatment

• As maintenance therapy after initial treatment to help keep the myeloma in remission

Many medicines and combinations of drugs can be used. If treatment stops working, another combination can be used.

How are these medicines given for multiple myeloma?

Before treatment starts, you’ll meet with a medical oncologist. This is a doctor who specializes in treating cancer with medicines. The doctor will talk with you about your treatment options and tell you what you can expect.

The medicines used to treat multiple myeloma can be given in these ways: 

• Intravenous (IV). You’ll get the medicine right into your blood through a catheter that’s been put into a vein. It might drip in slowly over a few hours, or you may get it over a few minutes.

• Subcutaneous (subQ). The medicine is given as an injection (shot) under your skin.

• Oral. You swallow these medicines as pills or liquids.

These medicines are most often given in an outpatient setting. This means you get them at a hospital, clinic, or healthcare provider's office. Then you go home after treatment. Rarely, you may need to stay in the hospital during treatment.

Your treatment team will watch you for reactions during your treatments. Since each of your treatments may last for a while, you may want to take something that’s comforting to you, like music to listen to. You may also want to bring something to keep you busy, such as a book or mobile device.

To reduce the damage to healthy cells and to give them a chance to recover, you’ll get these medicines in cycles. Each cycle consists of 1 or more days of treatment, followed by some time to rest. In general, cycles last 3 or 4 weeks. Your healthcare provider will discuss your treatment schedule with you.

Which medicines are used to treat multiple myeloma?

Chemotherapy (chemo)

Chemo is most often used when a stem cell transplant is planned. But it can be used when it's not, too. Common chemo drugs used to treat myeloma are:

• Bendamustine

• Cyclophosphamide

• Cisplatin

• Doxorubicin

• Etoposide

• Melphalan

• Vincristine

Immunomodulatory medicines (IMiDs)

The way immunomodulating medicines affect the immune system isn’t fully understood. There are three IMiDs used to treat multiple myeloma:

• Thalidomide

• Lenalidomide

• Pomalidomide

The first of these medicines to be developed was thalidomide. It causes severe birth defects when taken during pregnancy. Because the other immunomodulating medicines are related to thalidomide, it’s possible they might also cause birth defects. Because of this, you can only get these medicines through a special program run by the medicine company that makes them.

Targeted therapy medicines

There are many kinds of targeted therapy medicines used to treat multiple myeloma. They include:

• Proteasome inhibitors. These include bortezomib, carfilzomib, and ixazomib. These drugs target enzymes in cells (called proteasomes) to help control cell division.

• HDAC (histone deacetylase) inhibitors. Panobinostat is a medicine that affects proteins called histones. Some myeloma cells make a lot of HDAC, which helps them grow and divide quickly. Blocking this causes cell death.

• Monoclonal antibodies. These include daratumumab, isatuximab, elotuzumab, and belantamab. These medicines bind to proteins on the surface of myeloma cells. By doing this, they can kill the cells and/or help the immune system find and attack them.

• Nuclear export inhibitors. This medicine is called selinexor. It kills myeloma cells by keeping them from moving proteins they need to live and grow.

Corticosteroids (steroids)

Corticosteroids, such as dexamethasone and prednisone, are a key part of multiple myeloma treatment. They can be used alone but are often given along with other medicines. They can kill myeloma cells. They also help control side effects from the disease and other drugs used to treat it. For instance, they can help reduce bone pain, reduce calcium in the blood, and ease nausea and vomiting.

Bone-modifying medicines

These medicines help make bones strong and reduce the risk of bone fractures (breaks). Two types can be used. The choice depends on how well your kidneys are working:

• Bisphosphonates slow down the cells that dissolve bone (called osteoclasts). The drugs that can be used are pamidronate and zoledrinic acid. They can help keep myeloma from causing more bone damage and can reduce bone pain.

• Denosumab is a targeted therapy drug that targets osteoclasts to protect bone. It might be a better option for people with severe kidney problems.

Combining different types of medicines

Most of the time, more than 1 medicine is used to treat multiple myeloma. Many different combinations can be used. For instance, some common combos used as the first treatment for myeloma when transplant is possible include:

• Bortezomib, lenalidomide, and dexamethasone

• Bortezomib, cyclophosphamide, and dexamethasone

• Carfilzomib, lenalidomide, and dexamethasone

• Daratumumab, bortezomib, lenalidomide, and dexamethasone

• Ixazomib, lenalidomide, and dexamethasone

Combos used as the first treatment for myeloma when transplant is not planned include:

• Bortezomib, lenalidomide, and dexamethasone

• Daratumumab, cyclophosphamide, and dexamethasone

• Lenalidomide and low-dose dexamethasone

• Bortezomib, cyclophosphamide, and dexamethasone

One of the bone-modifying medicines is also given in most cases.

What are common side effects of these medicines?

All medicines used to treat multiple myeloma can cause side effects. Side effects can vary a lot based on the medicines and the combination of medicines used. Most side effects are short-term and get better over time after treatment ends. But some can be long-lasting.

Ask your healthcare provider for details about the side effects of the medicines you're getting and what can be done to help prevent them.

Side effects of chemotherapy

Chemo side effects are different for everyone. They vary based on the medicines and the doses you get. Some of the most common side effects of chemo include:

• Hair loss

• Nausea and vomiting

• Mouth and throat sores

• Loss of appetite

• Changes in how things taste

• Increased risk for infection

• Easy bleeding and bruising

• Extreme tiredness (fatigue)

Side effects of immunomodulating medicines

Thalidomide side effects can include:

• Drowsiness and fatigue

• Severe constipation

• Painful nerve damage (neuropathy)

• Blood clots

Lenalidomide side effects can include:

• Low platelets (thrombocytopenia)

• Low white blood cells

• Painful nerve damage (neuropathy)

• Blood clots

Pomalidomide side effects can include:

• Low red blood cells (anemia)

• Low white blood cells

• Blood clots

Side effects of targeted therapy medicines

Proteasome inhibitor side effects can include:

• Nausea and vomiting

• Tiredness

• Diarrhea or constipation

• Fever

• Loss of appetite

• Low blood cell counts, especially low platelet counts. This can increase your risk of bleeding and bruising.

• Nerve damage (peripheral neuropathy) that can lead to numbness, tingling, or pain in your hands and feet

HDAC inhibitor  side effects can include:

• Severe diarrhea

• Tiredness or weakness

• Nausea and vomiting

• Loss of appetite

• Fever

• Swelling in your arms or legs

Side effects of corticosteroids

Corticosteroid side effects can include:

• Increased appetite

• Weight gain

• High blood sugar levels

• Trouble sleeping

• Feeling like you have too much energy

Side effects bone-modifying medicines

The side effects of bone-modifying medicines can include:

• Flu-like symptoms

• Muscle and joint aches

• Anemia

• Kidney problems

• Death of bone in the jaw called osteonecrosis (rare but serious)

Working with your healthcare provider

It's important to know which medicines you're taking. Write their names down, and ask your healthcare team how each medicine works and what side effects each might have.

Talk with your healthcare providers about what signs to look for and when to call them. For example, chemotherapy can make you more likely to get infections, which can cause fever and chills. Make sure you know what number to call with questions. Is there a different number for evenings and weekends?

It may be helpful to keep a diary of your side effects. A written list will make it easier for you to remember your questions when you go to your appointments. It will also make it easier for you to work with your healthcare team to make a plan to manage your side effects.