(Reuters) Pfizer expects to begin a trial in humans this year of a small molecule pill designed to target the PCSK9 protein that maintains "bad" LDL cholesterol in the bloodstream, Dolsten said in an interview during the J.P. Morgan Healthcare conference in San Francisco.
He said animal trials of the experimental PCSK9 pill have demonstrated "a substantial reduction" in cholesterol.
Trials of Pfizer's experimental drug bococizumab, a large-molecule antibody that is given by injection every two weeks, have shown that it lowers cholesterol by around 60 percent.
"We view this as a franchise approach," Dolsten said.
He expects Pfizer's experimental PCSK9 vaccine, designed to induce the body to produce its own PCSK9 antibodies, to enter human testing in 2016.
"Imagine going to your doctor to get a shot for cholesterol," he said, noting that, if successful, the vaccine might eventually be an annual injection.
Amgen Inc, as well as a partnership of Regeneron Pharmaceuticals Inc and Sanofi SA, are also developing antibody drugs that target PCSK9. Wall Street analysts have forecast that each of the three could reach peak annual sales near $2 billion.
This current crop of PCSK9 inhibitors are monoclonal antibodies, proteins grown in living cells that need to be given by injection. They work differently from statins - pills that inhibit the liver's production of LDL cholesterol in the first place.
The injected drugs are being developed to treat patients who can't tolerate statins, or whose cholesterol cannot be controlled with the older drugs.
Dolsten said a PCSK9 pill might eventually be used for people with moderate to high cholesterol, while an antibody might be needed for those whose cholesterol is still very high despite the use of statins.
(Reporting by Deena Beasley; Editing by Alan Crosby)
