Advances in Leukemia Research
NCI-funded researchers are working to advance our understanding of how to treat leukemia. With progress in both targeted therapies and immunotherapies, leukemia treatment has the potential to become more effective and less toxic.
This page highlights some of the latest research in leukemia, including clinical advances that may soon translate into improved care, NCI-supported programs that are fueling progress, and research findings from recent studies.
Leukemia Treatment for Adults
The mainstays of leukemia treatment for adults have been chemotherapy, radiation therapy, and stem cell transplantation. Over the last two decades, targeted therapies have also become part of the standard of care for some types of leukemia. Different types of leukemia require different combinations of therapies.
Although much progress has been made against some types of leukemia, others still have relatively poor rates of survival. And, as the population ages, there is a greater need for treatment regimens that are less toxic.
Acute Lymphoblastic Leukemia (ALL)
Adult acute lymphoblastic leukemia (ALL) is a type of cancer in which the bone marrow makes too many lymphocytes (a type of white blood cell). It usually gets worse quickly and needs rapid treatment.
Combining less-toxic therapies. The intensive chemotherapy treatments used for ALL have serious side effects that many older patients cannot tolerate. Targeted therapies may have fewer side effects than chemotherapy. Clinical trials, including one at NCI, are now testing whether combinations of these types of therapies can be used instead of chemotherapy for older patients with a form of ALL called B-cell ALL.
- Currently, one type of CAR T cell is approved for the treatment of some children and young adults with ALL. They are now being explored for use in older adults with B-cell ALL.
- A second CAR T-cell therapy has been approved for adults with a type of ALL called B-cell precursor ALL that has not responded to treatment or has returned after previous treatment.
CAR T cells are now being explored for other uses in ALL. For example, scientists hope that it will be possible to use CAR T-cell therapy to delay—or even replace—stem-cell transplantation in older, frailer patients.
Improving Treatment for Adolescents and Young Adults (AYAs). An intensive treatment regimen developed for children with ALL has been found to also improve outcomes for newly diagnosed AYA patients. The pediatric regimen more than doubled the median length of time people lived without their cancer returning compared with an adult treatment regimen. Further studies are now testing the addition of targeted therapies to the combination.
Acute Myeloid Leukemia (AML)
Acute myeloid leukemia (AML) is the most common type of acute leukemia in adults. It can cause a buildup of abnormal red blood cells, white blood cells, or platelets.
AML tends to be aggressive and is harder to treat than ALL. However, AML cells sometimes have gene changes that cause the tumors to grow but can be targeted with new drugs. Researchers are starting to look at whether genomic sequencing of tumor cells can help doctors choose the best treatment (such as chemotherapy, targeted therapy, stem-cell transplant, or a combination of therapies) for each patient.
Targeted therapies. Targeted therapies recently approved to treat AML with certain gene changes include the below.
- Enasidenib (Idhifa)
- Ivosidenib (Tibsovo)
- Venetoclax (Venclexta)
- Gemtuzumab ozogamicin (Mylotarg)
- Midostaurin (Rydapt)
- Gilteritinib (Xospata)
- Glasdegib (Daurismo)
- Testing newer targeted therapies. Researchers continue to develop new drugs to shut down proteins that some leukemias need to grow.
- Studying ways to target AML cells indirectly. These include testing ways to make cancer cells more vulnerable to new and existing treatments.
- Targeting AML and related conditions. A type of less-aggressive cancer called myelodysplastic syndrome (MDS) can eventually progress to AML. Researchers are testing HDAC inhibitors and other drugs that alter how genes are switched on and off in both MDS and AML.
- Reducing side effects. Some older adults cannot tolerate the intensive treatments most commonly used for AML. Studies have recently found that several drug combinations can help older people with AML live longer while avoiding many serious side effects. New treatments to relieve symptoms of MDS have also been developed.
Monitoring response to treatment. The NCI-sponsored American College of Radiology Imaging Network (ACRIN) is currently analyzing results from a trial to see whether positron emission tomography (PET) scanning can be used instead of bone-marrow biopsy to monitor response to treatment in people newly diagnosed with AML. PET scans are not only less invasive than biopsies, but may also be able to detect whether treatment is working earlier than is possible with biopsies, which would allow for an earlier change in therapy if required.
Chronic Myelogenous Leukemia (CML)
Chronic myelogenous leukemia (CML) is a type of cancer in which the bone marrow makes too many granulocytes (a type of white blood cell). These granulocytes are abnormal and can build up in the blood and bone marrow so there is less room for healthy white blood cells, red blood cells, and platelets. CML usually gets worse slowly over time.
Most people with CML have a specific chromosome alteration called the Philadelphia chromosome, which produces an abnormal protein that drives the growth of leukemia cells. Targeted therapies that block this abnormal protein—imatinib (Gleevec), nilotinib (Tasigna), dasatinib (Sprycel), and ponatinib (Iclusig)—have radically changed the outlook for people with CML, who now have close to a normal life expectancy.
Testing new combination therapies. Some people with CML continue to have detectable cancer cells in their body even after long-term treatment with drugs that target the protein produced by the Philadelphia chromosome. NCI-sponsored trials are testing whether the addition of immunotherapy or other targeted therapies to these drugs can reduce the number of CML cells in such patients.
Can patients stop taking therapy? Researchers have found that some drugs that target the protein produced by the Philadelphia chromosome can be safely stopped in some CML patients rather than taken for life. These patients must undergo regular testing to ensure the disease has not come back.
Chronic Lymphocytic Leukemia (CLL)
Like ALL, chronic lymphocytic leukemia (CLL) is a type of cancer in which the bone marrow makes too many lymphocytes (a type of white blood cell). But unlike ALL, CLL is slow growing and worsens over time.
New drug approvals. Clinical trials have shown that the targeted therapy ibrutinib (Imbruvica) benefits both younger and older patients with CLL.
Ibrutinib was the first non-chemotherapy drug approved to treat CLL. It shuts down a signaling pathway called the B-cell receptor signaling pathway, which is commonly overactive in CLL cells. Depending on people’s age, ibrutinib may be given in combination with another targeted drug, rituximab (Rituxan).
In 2019, the Food and Drug Administration (FDA) approved the second chemotherapy-free initial treatment regimen for CLL, containing the targeted therapies venetoclax (Venclexta) and obinutuzumab (Gazyva).
Other combinations of these drugs plus ibrutinib are now being used or tested for CLL, including:
• ibrutinib and venetoclax in people with newly diagnosed CLL
• ibrutinib, obinutuzumab, and venetoclax in older adults with newly diagnosed CLL
• ibrutinib and obinutuzumab with or without venetoclax in younger adults with newly diagnosed CLL
An ongoing trial at NCI is also testing whether giving the combination of venetoclax and obinutuzumab to some people with CLL before symptoms develop can help them live longer overall.
CAR T-cell therapy. CAR T-cell therapy is also being tested in adults with CLL. Researchers would like to know if using this type of immunotherapy early in the course of treatment would be more effective than waiting until the cancer recurs.
Hairy Cell Leukemia (HCL)
Hairy cell leukemia (HCL) is a type of cancer in which the bone marrow makes too many lymphocytes (a type of white blood cell). The disease is called hairy cell leukemia because the abnormal lymphocytes look "hairy" when viewed under a microscope. This rare type of leukemia gets worse slowly, or sometimes does not get worse at all.
In 2018, the FDA approved moxetumomab pasudotox (Lumoxiti) for the treatment of HCL that has come back or progressed after earlier treatment. Originally discovered at NCI, the targeted therapy is the first non-chemotherapy drug approved for the disease.
Researchers are also studying combinations of drugs to treat HCL. For example, in a recent small study, a combination of two targeted therapies—vemurafenib (Zelboraf) and rituximab (Rituxan)—led to long-lasting remissions for most participants with HCL that had come back after previous treatments. More drug combinations are currently being tested in clinical trials.
Leukemia Treatment for Children
Standard leukemia treatments for children have been chemotherapy, radiation therapy, and stem-cell transplant. Despite great improvements in survival for children with some types of leukemia, some treatments don't always work. Also, some children later experience a relapse of their disease. Others live with the side effects of chemotherapy and radiation therapy for the rest of their lives, highlighting the need for less toxic treatments.
Now researchers are focusing on targeted drugs and immunotherapies for the treatment of leukemia in children. Newer chemotherapy drugs are also being tested.
Targeted therapies that have been approved or are being studied for children with leukemia include:
- dasatinib (Sprycel), which is approved for the treatment of children with CML and those with ALL. The approval is for children whose cancer cells have the Philadelphia chromosome.
- sorafenib (Nexavar), which is being tested in addition to standard chemotherapy for children with AML whose leukemia has changes in a gene called FLT3. Other drugs trials testing drugs that target FLT3 more specifically than sorafenib will be tested in trials that are being planned.
- larotrectinib (Vitrakvi), which is being tested in children with leukemia that has a specific change in a gene called NTRK.
More possible targets for the treatment of childhood cancers are discovered every year, and many new drugs that could potentially be used to treat cancers that have these targets are being tested through the Pediatric Preclinical In Vivo Testing Consortium (PIVOT).
CAR T-cell therapy has recently generated great excitement for the treatment of children with relapsed ALL. One CAR T-cell therapy, tisagenlecleucel (Kymriah), was approved in 2017 for some children with relapsed ALL.
Researchers continue to address remaining challenges about the use of CAR T-cell therapy in children with leukemia:
- Sometimes, leukemia can become resistant to tisagenlecleucel. Researchers in NCI’s Pediatric Oncology Branch have developed CAR T cells that target leukemia cells in a different way. An ongoing clinical trial is testing whether the combination of these two types of CAR T cells can provide longer-lasting remissions.
- CAR T cells are currently only approved for use in leukemia that has relapsed or proved resistant to standard treatment. A clinical trial from COG is now testing tisagenlecleucel as part of first-line therapy in children with ALL at high risk of relapse.
- More research is needed to understand which children who receive CAR T cells are at high risk of developing resistance to treatment. Researchers also plan to test whether strategies such as combining CAR T-cell therapy with other immunotherapies may help prevent resistance from developing.
- Other research, both in NCI’s Pediatric Oncology Branch and at other institutions, is focused on creating CAR T-cell therapies that work for children with other types of childhood leukemia, such as AML. Several clinical trials of these treatments, including one led by NCI researchers, are now under way.
Two other drugs that use the body’s immune system to fight cancer have shown promise for children with leukemia:
- A drug called blinatumomab (Blincyto) attaches to both T cells and cancer cells. By bringing these cells close together, the drug helps the T cells kill the cancer cells. Blinatumomab has been approved by the FDA for children with ALL who have relapsed after initial treatment. In clinical trials, the drug was shown to be more effective than chemotherapy in treating ALL that has relapsed in children and young adults.
- A drug called inotuzumab ozogamicin (Besponsa) is being tested in children with relapsed B-cell ALL. This drug consists of an antibody that can bind to cancer cells linked to a drug that can kill those cells.
In addition to targeted therapies and immunotherapies, researchers are also working to develop new chemotherapy drugs for leukemia and find better ways to use existing drugs. In 2018, a large clinical trial showed that adding the drug nelarabine (Arranon) to standard chemotherapy improves survival for children and young adults newly diagnosed with T-cell ALL.
Other drugs are being tested that may make standard chemotherapy drugs more effective. These drugs include venetoclax, which has been approved for older adults with some types of leukemia and is now being tested in children.
Children’s developing brains and bodies can be particularly sensitive to the harmful effects of cancer treatment. Because many children treated for cancer go on to live long lives, they may be dealing with these late effects for decades to come.
The NCI-funded Childhood Cancer Survivor Study, ongoing since 1994, tracks the long-term harmful effects of treatments for childhood cancer and studies ways to minimize these effects. NCI also funds research into addressing ways to help cancer survivors cope with and manage health issues stemming from cancer treatment, as well into altering existing treatment regimens to make them less toxic in the long term.
For example, a recent study found that, in children with ALL, radiation therapy to prevent the cancer from returning in the brain is likely unnecessary. The study found that radiation can even be omitted for children at the highest risk of the cancer coming back, reducing the risk of future problems with thinking and memory, hormone dysfunction, and other side effects of radiation to the brain.
NCI-Supported Research Programs
Many NCI-funded researchers working at the NIH campus and across the United States and the world are seeking ways to address leukemia more effectively. Some research is basic, exploring questions as diverse as the biological underpinnings of cancer. And some is more clinical, seeking to translate this basic information into improving patient outcomes. The programs listed below are a small sampling of NCI’s research efforts in leukemia.
NCI’s Leukemia Specialized Programs of Research Excellence (SPORE) promotes collaborative, interdisciplinary research. SPORE grants involve both basic and clinical/applied scientists working together. They support the efficient movement of basic scientific findings into clinical settings, as well as studies to determine the biological basis for observations made in individuals with cancer or in populations at risk for cancer.
The Pediatric Immunotherapy Discovery and Development Network (PI-DDN) is working to discover and characterize new targets for immunotherapies, design experimental models to test the effectiveness of pediatric immunotherapies, develop new immunotherapy treatments, and improve the understanding of tumor immunity in pediatric cancer patients. The PI-DDN was established as part of the Cancer Moonshot initiative.
The Fusion Oncoproteins in Childhood Cancers (FusOnC2) Consortium is also part of the Cancer Moonshot initiative. The consortium of collaborating research teams will work to advance the understanding of how five important fusion oncoproteins help drive pediatric cancers, including leukemia, and apply this knowledge towards developing drugs that target these proteins.
NCI has also formed partnerships with the pharmaceutical industry, academic institutions, and individual investigators for the early clinical evaluation of innovative cancer therapies. The Experimental Therapeutics Clinical Trials Network (ETCTN) was created to evaluate these therapies using a coordinated, collaborative approach to early-phase clinical trials.
The Pediatric Early-Phase Clinical Trials Network was established to help identify and develop effective new drugs for children and adolescents with cancer. The network’s focus is on phase I and early phase II trials, as well as pilot studies of novel drugs and treatment regimens to determine their tolerability.
NCI’s Pediatric Preclinical In Vivo Testing Consortium (PIVOT) develops mouse models to allow early, rapid testing of new drugs for pediatric cancers, including leukemia. The models are all derived from tissue samples taken from patients’ tumors. The consortium partners both with commercial drug companies and with drug development efforts at universities and cancer centers.
The Therapeutically Applicable Research to Generate Effective Treatments (TARGET) program uses a comprehensive approach to determine the genetic changes that drive childhood cancers. The goal of the program is to use data to guide the development of effective, less toxic therapies. TARGET is organized into disease-specific teams, including those for ALL and AML.
Researchers in NCI’s Division of Cancer Epidemiology and Genetics (DCEG) investigate novel, molecular biomarkers for leukemia, as well as clarify relationships of established risk factors. Studies include those looking at environmental and workplace exposure, families with multiple leukemia cases, and inherited bone marrow failure syndromes to name a few.
NCI funds and oversees both early- and late-phase clinical trials to develop new treatments and improve patient care. Search NCI-Supported Clinical Trials to find leukemia-related trials now accepting patients.
Leukemia Research Results
The following are some of our latest news articles on leukemia research:
- Ivosidenib with Chemotherapy New Option for Some People with AML
- Can Chronic Graft-Versus-Host Disease Be Prevented?
- Drug Combination Helps Children with Acute Promyelocytic Leukemia Avoid Conventional Chemotherapy
- Tecartus Becomes First CAR T-Cell Therapy Approved for Adults with ALL
- FDA Approval of Rylaze Will Address Drug Shortage for Childhood ALL
- For Hairy Cell Leukemia, Drug Combination Leads to Long-Lasting Remissions
View the full list of Leukemia Research Results and Study Updates.