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By Bill Berkrot
Oct 1 (Reuters) - An experimental cholesterol-fighting drugbeing developed by Esperion Therapeutics Inc loweredLDL levels significantly more than Merck & Co Inc's Zetia in a midstage clinical trial, Esperion said on Wednesday.
Esperion shares rose more than 40 percent in after-hourstrade.
In a 12-week study involving 348 patients with high LDLcholesterol, the Esperion drug, ETC-1002, led to an average 30percent reduction in levels of the "bad" cholesterol for thosewho received a 180 milligram dose and a 27 percent reductionwith a 120 mg dose, according to initial results.
Both were deemed to be statistically significant differencescompared with reductions in patients taking Zetia, knownchemically as ezetimibe, Esperion said.
The LDL reductions seen with the once-daily ETC-1002 pillwere somewhat less than can be achieved by more powerfulstatins, such as Pfizer Inc's Lipitor, now available asgeneric atorvastatin, and AstraZeneca Plc's Crestor. Thereductions were roughly half of the LDL-lowering magnitude seenwith new injectable biotech cholesterol drugs, called PCSK9inhibitors, likely to be approved next year.
The Esperion drug, when combined with 10 mg of Zetia, led toLDL reductions of 48 percent for the high dose of ETC-1002 and43 percent with the lower dose.
"These are very encouraging results. It basically showsefficacy, and it shows that it can be added to ezetimibe to getmore efficacy," Dr. Christie Ballantyne, chief of cardiology atBaylor College of Medicine in Houston and one of the study'sinvestigators, said in a telephone interview.
"Statins are going to stay first-line drugs," he said."There's lots of people who have a hard time taking a high doseof statin or taking a statin at all."
Esperion is also conducting trials combining its drug withvarious statins.
If approved, the Esperion drug is almost surely going to beless expensive than the more effective biologics, making it apotential option that physicians could reach for before puttingpatients on the injectables, Ballantyne said.
JMP Securities analyst Jason Butler has forecast annual peaksales in excess of $1 billion for the medicine.
ETC-1002 also led to significantly greater reductions thanZetia in C-reactive protein, a marker of inflammation associatedwith heart disease, the company said.
ETC-1002 is the first in a new class of drugs called ACLinhibitors that work by reducing cholesterol synthesis in theliver and increasing expression of LDL receptors that removecholesterol from the blood.
The most common side effects were common cold symptoms andupper respiratory tract infections. The rates of muscle-relatedadverse side effects seen with ETC-1002 patients, includingthose with statin intolerance, were similar to rates for Zetia,Esperion said.
Esperion shares rose to $35 in extended trading from aNasdaq close at $24.42. (Reporting by Bill Berkrot; Editing by Andre Grenon and LeslieAdler)
