New Weight-loss Drugs Look Like Slim Pickings, Say Dartmouth Researchers

(RTTNews) - After a 13-year dry spell in new obesity drugs, when the FDA finally gave green signal to Arena Pharmaceuticals Inc.'s (ARNA) Belviq and Vivus Inc.'s (VVUS) Qsymia in 2012, many had hoped that the two diet drugs will be the "magic bullets" for obesity and also become blockbusters. But it looks like physicians are yet to embrace the two drugs as can be seen from their disappointing sales.

An article by researchers, Steven Woloshin and Lisa Schwartz, of The Dartmouth Institute for Health Policy & Clinical Practice which appears in JAMA Internal Medicine, questions how safe Belviq and Qsymia are, which were approved based on the results of 1-year trials.

Patients who took either of the drugs in addition to following a calorie-restricted diet and increased exercise, lost more weight than patients randomized to placebo in the trials, based on which the drugs were approved by FDA.

However, safety concerns are associated with Belviq and Qsymia as the drugs' labels feature warnings about memory, attention, or language problems and depression. While Belviq's label also warns of valvular heart disease and euphoria, Qsymia's label warns of metabolic acidosis, increased heart rate, anxiety, insomnia, and elevated creatinine levels.

It should be noted that the European Medicines Agency, or EMA, did not approve Belviq or Qsymia as it found the two drugs to be too dangerous to be used for weight loss.

Arena Pharma withdrew its application for a marketing authorization for Belviq in Europe last May as it knew that the regulator, which was of the opinion that the benefits of Belviq did not outweigh its risks, was unlikely to approve the drug.

Qsymia was rejected by the EMA twice - first in 2012 and again in 2013, on concerns about the drug's long-term effects on the heart and blood vessels and about the long-term psychiatric effects and cognitive effects.

It's a well-known fact that both Belviq and Qsymia received FDA approval only on their second attempt in 2012, and the manufacturers of the drugs were required to conduct post-approval trials to assess cardiovascular harms.

Terming the FDA's decision to approve both the drugs and requiring post-approval than pre-approval safety trials as troubling, Schwartz and Woloshin say, "In our view, approving the drugs for marketing without more definitive evidence is an unnecessary gamble - one that the European regulatory agency was not willing to take."

The researchers also say that there is no evidence of the post-marketing trials happening on schedule as none of the trial protocols have been submitted to FDA (as of December 2013).

"FDA does not routinely require submission of post-marketing trials prior to approval. But they should. Based on the information that is currently available, the two new drugs look like slim pickings," the researchers said.