The weight management medicine Belviq (chemical name: lorcaserin), also available as Belviq XR, may possibly be linked to an increase in cancer risk, according to an announcement on Jan. 14, 2020, by the U.S. Food and Drug Administration (FDA).
About the possible increase in risk
The FDA said the way Belviq may increase cancer risk is unclear. It’s also not clear how much Belviq may increase cancer risk.
The FDA did not say people should stop taking Belviq. Instead, it advised patients to talk to their doctors about the risks and benefits of the medicine. The announcement also said doctors “should consider if the benefits of taking lorcaserin are likely to exceed the potential risks when deciding whether to prescribe or continue patients on lorcaserin.”
The FDA is continuing to evaluate results from studies on Belviq.
Belviq was approved by the FDA in 2012 to be used in combination with diet and exercise for people with a body mass index (BMI) of 30 or more or people with a BMI of 27 who also had other health problems linked to obesity, such as high blood pressure.
Belviq is a pill taken by mouth.
Belviq targets a hunger receptor in the brain and helps people feel full after eating smaller amounts of food and also seems to help people feel full longer. The exact way Belviq makes people feel full isn’t fully understood.
When Belviq was approved, the FDA asked the company that makes Belviq to conduct post-marketing studies because of concerns about Belviq causing heart valve disease.
Post-marketing study results
The CAMELLIA-TIMI-61 post-marketing study on Belviq found no increase in heart valve disease risk. It also showed that Belviq may decrease the risk of new-onset type II diabetes in people who were prediabetic before they started taking Belviq.
However, the study also found that more people taking Belviq were diagnosed with cancer compared to people taking placebo (a dummy pill that looks just like Belviq).
An FDA review document from 2012 noted that a study in rats found Belviq “caused mammary gland tumors in both sexes at clinically relevant exposures, with no safety margin identified for female rats.”
What this means for you
The FDA announcement is troubling, especially because so much is unknown:
- It’s not clear whether taking Belviq truly increases cancer risk.
- It’s not clear how Belviq might increase cancer risk.
- If Belviq does increase cancer risk, it’s not clear how large the increase is.
If you are currently taking Belviq to help with weight loss, it’s a good idea to talk to your doctor right away about the risks and benefits of continuing to take the medicine.
We know that overweight and obese women have a higher risk of being diagnosed with breast cancer compared to women who maintain a healthy weight, especially after menopause. We also know that being overweight can increase the risk of cancer coming back (recurrence) in women who have been diagnosed with the disease.
So it makes sense to talk to your doctor about any increase in risk you may have from excess weight and balance that against any increase in risk that may come from continuing to take Belviq.
Together, you and your doctor can make the best decision for you and your unique situation.
Stayed tuned to Breastcancer.org for updates on any safety issues related to Belviq.
Written by: Jamie DePolo, senior editor