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Qnexa Discovery: A Timeline

Qnexa wasn't really "discovered" at all. It was rather an idea born out of the disaster that was Fen-Phen and the idea was neither brilliant nor new: take two drugs that produce weight loss in different ways and combine them in the hope of achieving more weight loss than with either single drug alone.As you will see, this was the idea behind Fen-Phen and then Phen-Pro and finally phentermine and Topamax. It was an idea that many physicians including myself explored and continue to explore. With that in mind, here is a basic outline of how it all played out and where we stand today.

1959: Phentermine is approved by FDA for weight loss.

1979: Topiramate is discovered.

1988-1993: Dr. Micheal Weintraub releases studies showing that a combination of two appetite suppressants, fenfluramine and phentermine produce more and faster weight loss than either drug does alone. The "Fen-Phen" era is born.

1993-1996: Fen-Phen becomes the most popular weight loss drug cocktail in history.

1995-1996: Phase three pre-marketing clinical trials with Topamax clearly demonstrate that the drug causes weight loss as a side effect.

December 1996: Topamax approved by FDA as new anti-seizure medication.

1997: Topamax Launch: the drug becomes available to patients and pharmacies

1997: Spring: Alarming reports from the Mayo Clinic in Minnesota suggest that fen-phen may cause heart damage.

1997: September 15: Fenfluramine and Redux are voluntarily withdrawn from US, Latina American and European markets after a study released days earlier suggests that as many as 33% of people taking Fen-Phen may suffer heart valve damage. The Fen-Phen era is OVER.

1997: Weight loss doctors begin searching for an alternative to fenfluramine. By late 1997, the combination of phentermine and Prozac (Phen-Pro) is being advertised as a new and safer alternative to Fen-Phen.

1997: A few doctors, myself included, begin using Topamax and phentermine in some patients. The initial results are promising but for some patients, the side effects of Topamax are unpleasant.

1997-1999: Myself and a handful of doctors around the country continue using phentermine and topiramate in selected patients. 

1999: Dr. Thomas Najarian in Los Ojos California applies for and receives a patent for a "special" combination of phentermine and Topiramate.

1999-2002: Dr. Najarian convinces a tiny pharmaceutical company called Vivus to purchase the patent and pursue development of a new weight loss drug combination using phentermine and topiramate. This project ultimately becomes "Qnexa"

1999-Present: Physicians like myself continue to use phentermine and topiramate in patients with good results.

2012: February: An advisory panel to FDA strongly recommends approval of Qnexa as a new weight loss drug. The full FDA is set to vote in April.

2012: April: The FDA announces that it will delay its decision about Qnexa until July 17, 2012. Nearly everyone including myself expect the agency to approve the drug combination.