Arthritis Drug Xeljanz Carries Increased Cancer Risk; FDA Tells Drugmaker Pfizer To Update Warning Label; Can You Still Take Xeljanz?

The drugs Olumian and Rinvoq are also being asked to make these changes.

Published Sep 2, 2021

Chris Spargo

Cancer Warning for Xeljanz

  • The Food and Drug Administration has asked Pfizer to include a cancer warning on labels of its arthritis medication Xeljanz.
  • The agency “concluded there is an increased risk of serious heart-related events such as heart attack or stroke, cancer, blood clots, and death with the arthritis and ulcerative colitis medicines Xeljanz and Xeljanz XR.”
  • The FDA also asked drugmakers Eli Lilly and AbbiVie to include similar warnings on the labels of their respective medications Olumiant (baricitinib) and Rinvoq (upadacitinib).

Drugmaker Pfizer must include a cancer warning on Xeljanz, its arthritis medication, the Food and Drug Administration said.

“Based on a completed U.S. Food and Drug Administration (FDA) review of a large randomized safety clinical trial, we have concluded there is an increased risk of serious heart-related events such as heart attack or stroke, cancer, blood clots, and death with the arthritis and ulcerative colitis medicines Xeljanz and Xeljanz XR,” reads the statement released by the FDA.

That trial, completed in February, compared the effects of Xeljanz with a similar arthritis medication.

The results revealed that 4.19% of participants who were treated with Xeljanz developed cancer, as opposed to 2.89% of those who took a TNF blocker. (TNF blockers suppress the immune system by blocking the activity of TNF, a substance in the body that can cause inflammation and lead to immune-system diseases, according to the FDA.)

More specifically, lymphomas and lung cancers were observed at a higher rate in patients treated with Xeljanz as compared with individuals treated with TNF blockers.

Of particular note was the increased number of lung cancers cases observed in trial participants who smoked or had previously smoked that were treated with Xeljanz. Past and present smokers treated with Xeljanz were also at a greater risk of being diagnosed with all other cancers.

In addition to requiring Pfizer to note the increased risk of cancer associated with Xeljanz use on all prescription labels, the agency is also requesting that recommendations for health care professionals “include consideration of the benefits and risks for the individual patient prior to initiating or continuing therapy.”

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Out of an abundance of caution, the FDA is also requiring that the drug companies Eli Lilly and AbbiVie include similar warnings on the labels of their respective medications Olumiant (baricitinib) and Rinvoq (upadacitinib).

Those two medications were not included in the trial but, along with Xeljanz, belong to the class of medicines known as Janus kinase (JAK) inhibitors. (JAK inhibitors are a group of medications that inhibit activity and response of one or more of the Janus kinase enzymes that encourage inflammation.)

The FDA approved Xeljanz in 2012, almost 20 years after Pfizer joined forces with the National Institute of Health to develop the drug. Xeljanz, Olumiant, and Rinvoq have been approved for use in treating inflammatory conditions such as rheumatoid arthritis. Xeljanz is also approved to treat psoriatic arthritis, ulcerative colitis, and polyarticular juvenile idiopathic arthritis.

There was evidence of carcinogenesis (cancer formation) in animal studies conducted before human trials, but no definitive proof of any increased risks to humans until earlier this year when Pfizer released the results of its trial.

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What Should Xeljanz Users Do?

Individuals taking Xeljanz, Olumiant, or Rinvoq should inform their health care professionals.

Patients should also inform their health care professional if they have suffered a heart attack or similar cardiac incident, stroke, or been prone to blood clots in the past.

Those who smoke or used to smoke should also inform their health care professionals as they may be at a higher risk of suffering an adverse side effect while taking these medications.

And immediately seek medical attention if you are taking one of the drugs and suddenly experience:

  • Discomfort in the center of your chest that lasts for more than a few minutes, or that goes away and comes back
  • Severe tightness, pain, pressure, or heaviness in your chest, throat, neck, or jaw
  • Unusual pain or discomfort in your arms, back, neck, jaw, or stomach
  • Shortness of breath with or without chest discomfort
  • Breaking out in a cold sweat
  • Nausea or vomiting
  • Feeling lightheaded
  • Weakness in one part or on one side of your body
  • Slurred speech
  • Drooping on one side of your mouth
  • Swelling of a leg or arm
  • Leg pain or tenderness, or red or discolored skin in the painful or swollen leg or arm

Also reach out to your health care professional if you experience swelling of lymph nodes in your neck, armpits, or groin; constantly feeling tired; fever; night sweats; persistent or worsening cough; difficulty breathing; hoarseness or wheezing; or unexplained weight loss.

Carcinogens in Prescription Medication

This is the second time this summer that Pfizer has been forced to announce a cancer risk tied to one of its drugs at the request of the FDA.

The drug company recently announced the recall of four lots (16 total) of its popular smoking cessation drug Chantix at the consumer level due to the presence of nitrosamine in varenicline, which is the main component of the prescription medication.

The FDA had strongly urged these recalls after tests discovered carcinogenic levels of nitrosamine that far exceeded the amount at which consumption becomes a cancer risk.

“N-nitroso-varenicline may increase the risk of cancer if people are exposed to it above the acceptable intake limit and over a long period of time, but a person taking a drug that contains N-nitroso-varenicline at-or-below the acceptable intake limit every day for 70 years is not expected to have an increased risk of cancer,” explained the FDA.

“Agency scientists evaluated the risk of exposure to N-nitroso-varenicline at interim acceptable intake levels up to 185 ng per day (92.5 ppm) and determined that it presents minimal additional cancer risk when compared to a lifetime of exposure to N-nitroso-varenicline at the 37 ng per day (18.5 ppm) level.”

The levels of nitrosamine found in Chantix ranged from 155 to 474 ppm, far exceeding those acceptable intake levels.

The company had previously recalled two lots of Chantix 0.5mg tablets, two lots of Chantix 1 mg tablets, and eight lots of a Chantix kit of 0.5mg/1 mg tablets at the consumer level last month due to the presence of nitrosamine.

The issue is that the amount of the nitrosamine in question, N-nitroso-varenicline, that is present in the medication is above the Pfizer-established Acceptable Daily Intake (ADI) level.

The FDA had been urging the company to issue a recall at the consumer level for some time before they finally went forward with the move in June.

The FDA approved Chantix in May 2006 to help adults age 18 and over quit smoking, which remains the number one risk factor for developing lung cancer. The medication is typically used for 12 to 24 weeks.

Pfizer will continue to delay the release of varenicline in the U.S. until testing confirms that N-nitroso-varenicline levels are below what the company considers to be acceptable.

It is not all bad news for the company though, as Pfizer was the first to receive full FDA approval for its COVID-19 vaccine.

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Chris Spargo is a senior reporter at SurvivorNet. Read More