How Do Antineoplastic Camptothecins Work?

Antineoplastic camptothecins (CPTs) are a class of drugs used to treat various types of cancers including pancreatic cancer, colon or rectal cancer (cancer that begins in the large intestine), ovarian cancer (cancer that begins in the female reproductive organs where eggs are formed), cervical cancer (cancer that begins in the opening of the uterus), and small cell lung cancer.

CPTs are anticancer drugs isolated from the bark and stem of Camptotheca acuminata, a tree native to China used in traditional Chinese medicine. They selectively inhibit the nuclear enzyme DNA topoisomerase, type I and possess antitumor activity. They are potent topoisomerase inhibitors that interfere with the essential function of topoisomerase in DNA replication.

Antineoplastics CPTs are administered via intravenous (into a vein) route.

Antineoplastics CPTs work in the following ways:

• They belong to a class of antineoplastic medications called “topoisomerase I inhibitors” that work by slowing down or stopping the growth of cancer cells.
• They inhibit the action of topoisomerase I which prevents religation of the DNA strand by binding to topoisomerase I-DNA complex and causes breaking of double-strand DNA, thus leading to apoptosis (cell death).

Antineoplastics CPTs are used to treat conditions such as:

• Pancreatic cancer 
• Colorectal cancer
• Ovarian cancer 
• Small cell lung cancer
• Cervical cancer

Some of the common side effects include:

• Nausea
• Vomiting
• Constipation
• Back pain
• Diarrhea
• Abdominal pain
• Headache
• Tiredness/weakness
• Mouth sores
• Heartburn
• Loss of appetite
• Pain, redness, swelling, hardness, or itching at the injection site

Other rare side effects include:

• Dizziness 
• Fatigue 
• Weight loss
• Hair loss
• Anemia (low red blood cell count)
• Insomnia (trouble falling and/or staying asleep)
• Hypotension (low blood pressure)
• Shortness of breath
• Chills, sore throat, fever, or cough
• Chest pain
• Rash/hives/itching
• Yellowing of the skin or eyes
• Swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
• Thrombocytopenia (low blood platelet count)

Information contained herein is not intended to cover all possible side effects, precautions, warnings, drug interactions, allergic reactions, or adverse effects. Check with your doctor or pharmacist to make sure these drugs do not cause any harm when you take them along with other medicines. Never stop taking your medication and never change your dose or frequency without consulting your doctor.

Generic and brand names of antineoplastics CPTs include:

• Camptosar
• Hycamtin
• Irinotecan
• Irinotecan liposomal
• Onivyde
• Topotecan