Acomplia's bridesmaids wait their turn

Pfizer may be the world's most formidable source of me-too blockbusters, particularly when the company starts out a few years behind the first-in-class drug.

CP-945598, Pfizer's cannabinoid CB1 antagonist, begins its lifecycle approximately six years off the pace set by Acomplia. This may not be a pure disadvantage given the company's success with Lipitor, the fifth statin to market.

"We don't have a lot of data on the Pfizer compound yet," says Deutsche Bank's Ryan. "But everyone will pursue the opportunity. Obesity is a big problem, and there are a lot of other health consequences. If you reduce your weight and all other things remain the same, cardiovascular risk will go down. Risk of diabetes will go down. And at some point, I believe that there will be a breakthrough, but where it's going to come and which one it's going to be, I don't know."

Acomplia's manufacturer, Sanofi-Aventis, has its own me-too drug positioned to profit from any shortcomings of the prospective blockbuster. In SR 147778, the company made nearly cosmetic changes, replacing a chlorine atom with a bromine and adding a CH3 group.

CP-945598 by Pfizer
Projected Launch
2012
SR 147778 by Sanofi-Aventis
Projected Launch
2010

AMG 162 [denosumab] by Amgen

TARGET INDICATION
Osteoporosis
DEVELOPMENT
Phase III
LAUNCH DATE
2008
PEAK ANNUAL SALES
$1 billion plus

Barbara Ryan, Managing Director, Deutsche Bank

"This one has really gotten a lot of buzz at the major meetings," says Sheryl Vondracek, PharmD, professor of clinical pharmacy at the University of Colorado at Denver. "The drug is going to be the first one in its class. It is an antibody against a particular binding receptor that initiates bone resorption. So it blocks the receptor that stimulates the cell that breaks down and assimilates bone."

So far, the drug has proved safe and popular at trials, not least because doses are injected just once every six months. It is slated to compete with two biphosphanates that inhibit osteoclast activity using a different mechanism. Fosamax (alendronate), a once-weekly pill, posts sales between $3 and $4 billion a year, according to ADIS. Zoledronic acid, sold as Zometa by Novartis, has sales of nearly $2 billion, and is being reformulated as a once-a-year injection, according to Vondracek.

"We expect denosumab to come in north of a billion dollars," says Molowa. "Especially if it can be launched in 2008," when the patent on Fosomax expires.

Exubera [insulin] by Pfizer/Nektar Therapeutics

TARGET INDICATION
Diabetes
LAUNCH DATE
2006
ADIS RATING
75
PEAK ANNUAL SALES
$2.25 billion