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Does The Weight Loss Drug Belviq Cause Cancer?

Does The Weight Loss Drug Belviq Cause Cancer?

Huntsville Personal Injury Lawyers

Weight Loss Drug Health Risks

Does the drug Belviq cause cancer? Are patients being injured by this medication? Recent research casts a big shadow over this drug. We are closely watching current developments.

What Is Belviq? Why Was It Marketed?

Belviq is a diet pill intended to treat certain overweight adults. What specific conditions were treated by Belviq? The drug was approved to treat adults with a body mass index (BMI) of 30 or higher (obese adults) OR adults with a BMI of 27 or greater (overweight adults) who also had certain weight-related conditions. These conditions include high blood pressure (HBP), high cholesterol or Type-2 diabetes.

The American drug company Arena Pharmaceuticals discovered and developed Lorcaserin (the active drug in Belviq). Arena Pharmaceuticals then licensed the drug to the Japanese pharmaceutical company Eisai, Inc., for production and distribution. Belviq and Belviq XR (extended release version approved at a later date) are distributed by Eisai. The Japanese company maintains its U.S. headquarters in New Jersey, has thousands of employees throughout much of the world, and earns annual revenues exceeding $600 Billion.

Why did the Food & Drug Administration (FDA) approve Belviq? The FDA approved Belviq in 2012. The FDA granted approval based on very limited clinical trials involving less than 8,000 patients who used the drug for a limited time. The active ingredient in Belviq is a drug called lorcaserin. Lorcaserin works by activating the serotonin 2C receptor in the patient’s brain. Researchers believe this activation helps the patient feel full after eating small amounts or portions of food. Basically, Belviq affects chemical signals in the brain that control appetite. Patients feel satisfied and eat less food.

It’s important to note that the serotonin 2C receptor was also targeted by fenfluramine in Fen-phen, the dangerous drug pulled from the market in 1997. Fen-then was pulled less than 2 years after approval when linked to heart valve issues in up to 1/3 of patients who used the drug.

Like so many drugs, the FDA approves medications based on limited or short-sighted studies. Then, doctors rely on the approval believing the drug to be genuinely safe. And, innocent patients begin to use the drug. Only years later, after many innocent patient injuries, is the truth revealed.

Did Belviq benefit patients? Was it worth it? In 2013, just a year after the drug’s approval, Consumer Reports published an article on the medication. The Consumer Reports article raises this question and answers with “we say skip it.” According to the Consumer Reports article, the beneficial results were few — “People who take the drug for a year can expect to lose just 3 to 3.7 percent of their weight.  .  .  .” And, “what’s more, the drug can cause several side effects including, headache, dizziness, fatigue, nausea, dry mouth, and constipation.” The Consumer Reports article uses phrases like “risks galore” and “skip it.” The article concludes with caution because the potential benefits are “minimal” while the risks are “troublesome.” That’s certainly NO endorsement of the medication. And, this article was published well before cancer issues were publicly known.

What Patient Injuries Are Associated With The Drug?

When we look at the history of Belviq, it’s important to ask what physicians and patients did NOT know when the drug was first approved. What important health risks were NOT disclosed? The FDA only approved Belviq in 2012 after serious discussions back-and-forth between regulators and the company. What was the topic of those discussions? Cancer risks. The FDA’s advisory panel initially rejected the drug because of concerns about tumors found in animal studies. Although Eisai eventually won approval in the United States, it withdrew the application in Europe where approval was not likely.

FDA approval in 2012 was contingent upon long-term studies evaluating the risk of cardiovascular problems. The subsequent studies tracked about 12,000 people over the course of a five-year period. The focus moved from cardiovascular questions when the data revealed potential cancer issues. According to the study, cancer occurred more frequently in patients taking Belviq.

On February 13, 2020, the FDA urged Eisai to remove Belviq from the market. In its announcement, the FDA stated:

The U.S. Food and Drug Administration (FDA) has requested that the manufacturer of Belviq, Belviq XR (lorcaserin) voluntarily withdraw the weight-loss drug from the U.S. market because a safety clinical trial shows an increased occurrence of cancer. The drug manufacturer, Eisai Inc,. has submitted a request to voluntarily withdraw the drug.

.  .  .

We are taking this action because we believe that the risks of lorcaserin outweigh its benefits based on our completed review of results from a randomized clinical trial assessing safety.

According to the FDA, the risks of Belviq outweigh the potential benefits. Often, drug makers “voluntarily” withdraw their products from the market rather than face the negative impacts of a formal safety recall.

The FDA recommended people stop taking Belviq and discuss alternative weight loss treatments with their doctors. What types of cancer may be at issue? Several types of cancer occurred more frequently with the lorcaserin group in the study. Those cancers included:

  • Lung Cancer
  • Colorectal Cancer (Colon and Rectal Cancer)
  • Pancreatic Cancer

At the Blackwell Law Firm, we are currently investigating potential cancer injury cases involving Belviq. We will be closely watching as additional data and research is produced about this weight loss drug and the potential for cancer.

If you have questions about Belviq, let us know. In prior years, we have pursued claims involving other carcinogenic drugs. These include drugs such as Actos, a diabetic medication linked to bladder cancer. We are presently investigating claims involving several different drugs due to the risk of cancer injury. These other cases include the antacid drug Zantac. For information on Zantac (generic name Ranitidine), I’ve written and published an extensive report which can be found by clicking the Hot Topics tab on our law firm website. With Zantac, current research shows the medication produces NDMA as a by-product. NDMA is a highly carcinogenic chemical.


From its office in Huntsville, the Blackwell Law Firm represents clients across Alabama. Our firm focuses solely on serious personal injury claims and cases. Many of our cases involve bad drugs and dangerous medical devices. If you have questions, let us know. We are happy to discuss your personal injury issues. Consultations are always free and confidential.