Breast Cancer Lawsuit Filed Over Side Effects of Recalled Diet Drug Belviq

According to allegations raised in a recently filed product liability lawsuit, drug maker failed to adequately warn about the link between breast cancer and Belviq, indicating the side effects of the recalled diet drug caused a Louisiana woman’s diagnosis years after she stopping taking the medication.

The complaint (PDF) was filed by Maryann Kaylor, and her husband, Willard, in the U.S. District Court for the Western District of Louisiana on January 11, pursuing damages against Eisai, Inc. and Arena Pharmaceuticals as defendants.

Belviq (lorcaserin) was introduced as a new prescription weight-loss medications in 2012, following years of recalls and problems linked to earlier products. However, early last year the FDA required the drug makers to issue a Belviq recall after warning about an increased incidence of cancer among users of the medication.

Kaylor indicates she became one of those users in September 2014, and continued to take the drug to help her lose weight until March 2015, according to her lawsuit. However, in January 2020, she was diagnosed with breast cancer, which Kaylor indicates was a direct result of the Belviq exposure years earlier.

“From the date Defendants received FDA approval to market Belviq, Defendants made, distributed, marketed, and sold Belviq without adequate warning to Plaintiff’s prescribing physicians or Plaintiff that Belviq was associated with and/or could cause cancer, presented a risk of cancer in patients who used it, and that Defendants had not adequately conducted complete and proper testing and studies of Belviq with regard to carcinogenicity,” the lawsuit states. “Defendants’ failure to disclose information that they possessed regarding the failure to adequately test and study Belviq for cancer risk further rendered warnings for this medication inadequate.”

Although pre-market testing suggested that Belviq exposure in rats may cause cancerous tumors, it was introduced without any warnings about the cancer risk. However, a post-marketing study involving 12,000 subjects that monitored users for five years found an increased incidence of cancer with Belviq compared to the placebo group.

Belviq Cancer Side Effects

After an FDA advisory panel decided to approve the medication in April 2012, the consumer watchdog group Public Citizen predicted there would be problems with Belviq, and that the diet drug would eventually be removed from the market like a number of other previously-approved weight-loss treatments.

In July 2019, an expert analysis of the CAMEILLIA-TIMI 61 Trial was published by the American College of Cardiology. The study looked at the effectiveness and side effects of Belviq, including the largest concern at the time: cardiovascular risks.

While not publicly announced until months later, the data contained concerning indications about a potential link between Belviq and pancreatic cancer, colorectal cancer and lung cancer. However, the FDA did not issue Belviq cancer warnings until January 2020, and several weeks later it was determined the weight loss drug needed to be removed from the market.

According to data from the five year follow up study involving about 12,000 participants, which was intended to evaluate the potential heart risks associated with the medication, at least 462 individuals treated with Belviq were diagnosed with 520 different primary cancers.

The complaint filed by Kaylor joins a growing number of Belviq cancer lawsuits being pursued nationwide, and the size of the litigation is expected to continue to grow in the coming months and years, as former users diagnosed with cancer discover that the injury may have been caused by exposure to Belviq.