Monoclonal Antibodies

These are a new class of caner treatment drugs that act in an immunological way. Rituxan was the first of monoclonal antibodies to become commercially available for treatment of Low Grade Lymphomas. This is a rather well tolerated drug that has shown reasonable efficacy against certain lymphomas. Rituxan is an antibody that selectively binds to CD-20 antigen on the surface of lymphoma cells. CD-20 is present in over 90% of low-grade lymphomas. This drug also depletes normal CD-20 lymphocytes as well. Clinical trials with this drug have shown almost 50% response in patients who had have failed a prior chemotherapy and had progressive and refractory lymphoma. This drug is given intravenously, on a weekly basis for four weeks. The infusion should be slow and may be given in an out patient setting. Pre-medications with Tylenol and Benadryl should be used to prevent potential allergic reaction to this drug.

Side effects:

The first infusion is usually takes about 4-6 hours and may be associated with side effects as mentioned bellow. These side effects may be due to the destruction of both normal and malignant Lymphoma cells and release of substances from inside these cells. The subsequent infusions are better tolerated and may be associated with fewer side effects and can be given over 2-4 hours.

Fever, Chills may happen in majority of patients and can be helped with using Tylenol prior to the administration of the drug.
Nausea, vomiting
Fatigue
Skin Rash
Low blood pressure
Asthma and shortness on breath\
Low White blood counts
Low platelet counts
Fluid retention

Destruction of normal lymphocytes does not seem to be associated with increased risk of infections.

Herceptin (trastuzumab)

This drug is one of the most recently released anticancer drugs. Herceptin is a protein, an antibody to a product of a gene that may be present in some patients with breast cancer. Certain Genes play a role in cancers. Oncogene HER-2 may be present in breast cancer cells and produce a protein that would be present at the surface of cancer cells. When this protein is present on the cell surface, Herceptin can detect and bind to it and subsequently cause damage and destruction of such cancer cells. Herceptin is a unique antibody and is similar to Rituximab that is used in treatment of lymphomas.

This drug is approved for treatment of metastatic breast cancers that do express the HER-2 gene induced protein on their surface. Clinical trials with this drug have shown objective responses in 20-25% of patients. Treatment can result in durable responses and in some patients lasting beyond two years.

Side effects:

Side effects are mild and infrequent. Most important side effects are:

Anemia
Fever, Chills may happen and can be helped with using Tylenol prior to the administration of the drug.
Nausea, vomiting
Fatigue
Skin Rash
Low blood pressure
Headache
Low White blood counts
Fluid retention
Soreness in the mouth
Hair loss