Belviq (lorcaserin) is a new diet drug that was released on the U.S. market in June 2012 — one of the first new diet drugs in more than a decade. Unfortunately, our lawyers are concerned because clinical trials of Belviq have found alarming evidence of psychiatric disorders, heart valve damage, cancer (breast and brain tumors were found in rodents), and other severe, life-threatening side effects.
UPDATE: Belviq Hits U.S. Market in 2013
June 7, 2013 — Almost exactly one year after receiving approval from the FDA, Arena Pharmaceuticals has announced that Belviq will be available for sale in the United States beginning next week.
June 27, 2012 — Belviq approved by the FDA, despite safety concerns. Click here to read more.
What is Belviq?
Belviq (lorcaserin), developed by Arena Pharmaceuticals and marketed by Eisai Co., Ltd., was approved by the U.S. Food and Drug Administration (FDA) in June 2012 — the first new weight-loss medication since Fen Phen and Redux were recalled in 1997.
In addition to diet and exercise, Belviq helps patients lose weight by targeting serotonin. This makes patients feel satisfied and full, which can help some patients eat less food and lose weight. Clinical studies of Belviq showed the average one-year weight-loss was between 3% and 3.7% of a patient’s total body weight.
What is the problem with Belviq?
Belviq is that it is a new drug with unknown long-term side effects. Serotonin, the neurotransmitter Belviq targets, plays many roles in the body in addition to influencing feelings of fullness — especially in the heart, gastrointestinal system, nervous system, and more.
Medications that adversely influence the serotonin system can have a lot of different side effects. In some cases, long-term side effects like cancer and heart disease do not appear in clinical trials.
FDA Approval Despite Concerns of Belviq and Cancer
The drug-makers behind Belviq sought FDA approval for several years before finally gaining it in June 2012. An FDA panel rejected Belviq in October 2010 because of studies linking Belviq and cancer. Those studies involved rodents who developed brain and breast cancer after being given doses of Belviq that were 7-times the dose a human would receive.
Arena Pharmaceuticals assured the FDA that the tumors were rodent-specific and did not apply to humans. The panel ultimately voted 18-4 to approve Belviq in June 2012.
Belviq and Heart Valve Damage
Heart valve damage is one of the biggest concerns surrounding Belviq because the last two diet drugs, Fen Phen and Redux, caused this side effect in tens of thousands of people before they were recalled in 1997. In clinical trials of Belviq, approximately heart valve damage occurred in 2.4% of Belviq patients, compared to 2% of placebo patients. Furthermore, Belviq patients had decreased heart rate — about 1-2 beats per minute slower than placebo patients.
Belviq works very similarly to fenfluramine, an ingredient in Fen Phen. Both target the serotonin 2C receptors involved in feelings of fullness and appetite. However, the makers of Belviq claim it is more selective.
The Prescribing Information for Belviq does not recommend patients to have evaluations for pre-existing or developing heart valve disease. It simply warns:
“Some people taking medicines like Belviq have had problems with the valves in their heart. … Before taking Belviq, tell your doctor if you have or have had any heart problems.”
Belviq Side Effects
Common side effects of Belviq:
- More side effects in diabetics: Low blood-sugar, back pain, cough.
Most serious Belviq side effects:
- Heart problems
- Heart valve damage
- High blood pressure in lungs (pulmonary hypertension)
- Decreased heart rate
- Cancer (studies of rodents found signs of breast and brain tumors)
- Psychiatric disorders (euphoria, dissociation, depression, etc.)
- Cognitive impairment (memory loss, confusion, lost attention)
- Serotonin Syndrome
- Neuroleptic Malignant Syndrome (NMS)
- Increased prolactin (hormone that can cause gynecomastia or galactorrhea)
- Gynecomastia (growth of male breasts)
- Galactorrhea (female breast-milk production)
- Anemia or low white blood-cell count
- And more