Off-Label Drug Use in Cancer Treatment: What You Need to Know

When the FDA is satisfied that the drug works and is safe, it and the maker of the drug create the drug label. This is not an actual label that sticks to a bottle, but a report of very specific information about the drug. The FDA must approve this report, which is made available to all health professionals who prescribe or sell the drug. 

The drug label gives information about the drug, including the specific medical condition(s) it’s approved for, the doses to be used, and how it’s to be given. When a drug is used in a way that is different from that described in the FDA-approved drug label, it’s said to be an “off-label” use. 

This can mean that the drug is:

  • Used for a different disease or medical condition
  • Given in a different way (such as by a different route)
  • Given in a different dose than in the approved label

The off-label use of FDA-approved drugs is not regulated, but it is legal in the United States and many other countries. An exception to this is the use of some controlled substances, such as opioids (pain medicines like morphine and fentanyl). These drugs cannot legally be prescribed in the United States except for approved purposes.

While it’s legal for doctors to use drugs off label, it’s not legal for drug companies to market (advertise or promote) their drugs for off-label uses. Off-label marketing is very different from off-label use.

some reasons a doctor may prescribe a drug for off-label use:

  • There is no FDA-approved drug available to treat a person’s condition.
  • The drugs that the FDA have approved for a particular condition have not been effective for the person.
  • The drugs that the FDA have approved for a particular condition are too expensive or otherwise inaccessible.
  • A person is unable to take the FDA-approved drug due to side effects or possible interactions with other drugs they are taking.
  • The doctor has seen evidence that a certain drug works well for a particular off-label use.

Off-label drug use is common in cancer treatment because:

  • Some cancer drugs are found to work against many different kinds of tumors.
  • Chemotherapy treatments often combine drugs. These combinations might include one or more drugs not approved for that disease. Also, drug combinations change over time as doctors study different ones to find out which work best.
  • Cancer treatment is always changing and improving.
  • Oncologists (cancer doctors) and their patients are often faced with problems that have few approved treatment options. This is especially true for less common types of cancer.
  • Oncologists and their patients may be more willing to try off-label drugs than other medical specialties.

A person should ask their doctor the following questions when receiving a prescription drug for the first time:

  • What does this drug have approval for?
  • What are the benefits of taking this drug over a drug that has approval for my condition?
  • What scientific evidence is there to show that this drug could work for my health condition?
  • What kind of results should I expect to see while taking this drug?
  • What are the side effects of this drug?
  • What dosage should I take?
  • Will this drug interact with other drugs, supplements, or herbs that I am taking?
  • What are the other options for treating my condition?

Lists of some FDA-approved drugs alongside their FDA-approved uses and their common off-label uses:

FDA-approved drugFDA-approved useOff-label use
tamoxifenTreating breast cancertreating certain causes of infertility in females
spironolactoneTreating high blood pressure, heart failure, edema and Conn’s syndrometreating acne vulgaris in females
modafinilimproving wakefulness in people with narcolepsy, obstructive sleep apnea, or shift work sleep disordertreating depression
escitalopramtreating depressionTreating bipolar disorder