Summary and Conclusions
In This Section:
Finding the Right Combinations
Since multiple signaling pathways are often disrupted in cancer cells, many clinical trials are testing combinations of targeted therapies. It is hoped that targeting multiple pathways might reduce the development of drug-resistant tumor cells.
For example, an mTOR inhibitor is being tested in combination with Rituxan® (rituximab), the monoclonal antibody that interacts with CD20. Preclinical studies have shown that diffuse large B cell lymphoma cells treated with an mTOR inhibitor are more sensitive to the cytotoxic effects of Rituxan® (rituximab).
Accessing Targeted Therapies for Lymphoma
A few targeted therapies have already been approved by the FDA for treatment of lymphoma. For a list of these drugs and their approved uses, click on the Additional Information link at the bottom of the screen.
Several other targeted therapies are being developed for use against lymphoma. Doctors should consider whether a clinical trial of innovative targeted therapies might be a good option for their patients.
Approved Targeted Drugs
Targeted therapies that are approved by the FDA for the treatment of lymphoma:
- Mechanism: The antibody binds to the CD20 antigen on B lymphocytes and recruits immune effector functions to mediate B cell lysis in vitro; possible mechanisms of cell lysis include complement-dependent cytotoxicity and antibody-dependent cell-mediated cytotoxicity. The antibody has also been shown to induce apoptosis in vitro.
- As a single agent for treatment of patients with relapsed or refractory, low-grade or follicular, CD20-positive B cell non-Hodgkin lymphoma
- In combination with CVP (cyclophosphamide, vincristine, and prednisone) chemotherapy for treatment of patients with previously-untreated follicular, CD20-positive, B cell non-Hodgkin lymphoma
- As a single agent for treatment of patients with non-progressing, low-grade, CD20-positive, B cell non-Hodgkin lymphoma who have been previously treated with CVP (cyclophosphamide, vincristine, and prednisone) chemotherapy
- In combination with CHOP (cyclophosphamide, doxorubicin hydrochloride [hydroxydaunorubicin], vincristine [Oncovin®], and prednisone) or other anthracycline-based chemotherapy regimens for treatment of patients with previously-untreated diffuse large B cell, CD20-positive non-Hodgkin lymphoma
Ibritumomab tiuxetan (Zevalin®)
- Mechanism: The antibody binds specifically to the CD20 antigen on B lymphocytes. The beta emission from Y-90 (yttrium-90) induces cellular damage by the formation of free radicals in the target and neighboring cells.
- Indications: As part of the Zevalin therapeutic regimen for treatment of relapsed or refractory, low-grade or follicular B-cell non-Hodgkin lymphoma, including patients with rituximab refractory follicular non-Hodgkin lymphoma
- Mechanism: The antibody binds specifically to the CD20 antigen on B lymphocytes. Possible mechanisms of action include induction of apoptosis, complement-dependent cytotoxicity, and antibody-dependent cellular cytotoxicity. Additionally, cell death is associated with ionizing radiation from I-131 (iodine-131).
- Indications: The Bexxar therapeutic regimen is indicated for treatment of patients with CD20 antigen-expressing relapsed or refractory, low grade, follicular, or transformed non-Hodgkin lymphoma, including patients with rituximab-refractory non-Hodgkin lymphoma. The Bexxar therapeutic regimen is not indicated for the initial treatment of patients with CD20-positive non-Hodgkin lymphoma.
- Mechanism: Histone deacetylase inhibitor
- Indications: Indicated for treatment of cutaneous manifestations in patients with cutaneous T cell lymphoma who have progressive, persistent, or recurrent diseases on or following two systemic therapies.
Finding Clinical Trials
Targeted therapies for lymphoma are in all phases of clinical study.
There are a number of ways to find clinical trials. The National Cancer Institute’s Web site—www.cancer.gov/clinicaltrials—contains information about clinical trials sponsored by the National Cancer Institute, pharmaceutical companies, medical centers, and other groups from around the world. For information on cancer clinical trials being conducted at the National Institutes of Health Clinical Center, visit www.bethesdatrials.cancer.gov. Information about clinical trials can also be found on the ClinicalTrials.gov Web site, which is operated and maintained by the U.S. National Library of Medicine.
Cancer patients and their families may also contact NCI’s Cancer Information Service (CIS) if they have questions about cancer and clinical trials. The CIS can be reached by calling 1-800-4-CANCER. Or, patients can use the Live Chat feature on the Cancer.gov Web site.