Jim Edwards asks a question that many Big Pharma watchers are asking, too: “What will happen when Viagra goes generic?”  The BNET pharmaceutical writer and former managing editor of Adweek offers this best guess in an AccessRx column:

“When the drug giant Pfizer loses its patent protection for its erectile dysfunction drug Viagra, any drug company will be able to make and sell a cheap generic version of the blockbuster drug. Doctors and lawyers believe that the expiration of Pfizer’s monopoly on the drug will be good news for patients, as it will force competition between Pfizer’s Viagra and the new generic versions, dramatically driving down the price not only of Viagra but also of Eli Lilly’s Cialis and Bayer’s Levitra.

“However, increased options and cheaper prices for patients will lead to some confusion in the marketplace as Pfizer defends the reputation of its original brand and pharmacies become flooded with copycat pills, many of which may be made in China. 

“Here are some signs to watch for – and some warnings to heed – in the run-up to the launch of generic Viagra.

“Viagra, Cialis and Levitra are the only erectile dysfunction drugs currently allowed by the FDA in the U.S.  Viagra, as the oldest of the three, will lose its monopoly status first. (Levitra expires in 2018 and Cialis expires between 2017 and 2020.)

“Once the patent expires, the floodgates will open and consumers will likely be bombarded with advertising for cheap generic sildenafil citrate (legally, they will not be able to use the brand name “Viagra”).

“Until now, Pfizer has raised the price of Viagra between 5% and 11% every year, to $14 per pill at the wholesale level. That price will plummet.”

So what possible options does Edwards think Pfizer has when considering that Viagra will soon be falling off the patent cliff?

• One option for Pfizer upon Viagra’s patent expiration is to “stay the course” and market itself as the original ED pill. More than 25 million men have used Viagra, and many may not want to switch.

• A second option is for Pfizer to apply for OTC (over-the-counter) status for Viagra with the FDA.
  

• A third option is to license the original recipe of Viagra to other companies while producing an “upgraded” version of Viagra that can continue to hold value as a patented product.

Pfizer may be hoping, adds Edwards, to persuade the FDA to give it some kind of behind-the-counter status – such as already exists in the U.K.  – in which patients can buy it without prescription as long as the pharmacist is assured that the patient isn’t on nitrates for blood pressure (mixing Viagra with nitrates can be fatal).

Pfizer has four of the 15 biggest patent expiries in the U.S. in the next two years. Besides Viagra, Pfizer’s heartburn medicine Protonix and its anti-psychotic Geodon will all face generic competition.

All of which likely means Pfizer‘s reign as the world’s biggest drug company will soon be over. Analysts expect Novartis to become the world’s biggest seller of prescription and over-the-counter drugs next year.

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* UPDATE: Pfizer’s patent rights on Viagra were originally set to expire in 2012. But when generic companies moved to enter the market, Pfizer piled on a “method-of-use” patent over the same drug, set to expire in 2019. A federal judge upheld that patent after a bench trial, so Pfizer will be the only company allowed to sell sildenafil in the U.S. until 2019. More here.

See also:

• New ‘Desire Drug’ Claims that Sex Really IS All in Her Head
• “Pay for Delay”- How Off-Patent Brand Name Drugs Fight Off Generics 
• Lipitor – and Nine Other Blockbuster Drugs that are Falling Off the ‘Patent Cliff’
• Generic drugs: Are They Really ‘Exactly’ the Same as Brand Name Drugs?
• How a New Drug Gets Approved

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