Sept 2 (Reuters) - Merck's ( MRK ) oral drug met the

main goal of reducing bad cholesterol in a late-stage trial, it

said on Tuesday, marking a second win for the drug since June.

The trial data provides a shot in the arm for the company,

which is looking for its next blockbuster candidate as its major

revenue driver, Keytruda, is expected to lose patent protection

by the end of the decade.

Merck's ( MRK ) non-statin cholesterol drug, enlicitide decanoate,

was being tested in patients with hypercholesterolemia, a

condition characterized by elevated levels of LDL (bad)

cholesterol in the blood, often leading to plaque buildup in the

arteries.

The condition affects about 73.5 million Americans, leading

to increased risk of heart disease, according to government

data.

In the 24-week trial, Merck's ( MRK ) drug showed meaningful

reductions in LDL cholesterol, when compared to placebo.

In June, the cholesterol pill succeeded in two late-stage

studies when tested for the treatment of hyperlipidemia, a

condition that causes elevated buildup of fat in the blood

vessels potentially leading to heart attacks and strokes.

Enlicitide works by blocking PCSK9, a protein that plays a

crucial role in regulating cholesterol levels, while statins

block an enzyme the liver uses to make cholesterol.

Analysts have noted that the drug has blockbuster potential

that expands the PCSK9 market beyond current injectable

therapies.

Merck's ( MRK ) drug is designed to lower LDL cholesterol

through the same biological mechanism as the currently approved

injectable PCSK9 inhibitors, but in a daily pill form.

Similar treatments in development include AstraZeneca's ( AZN )

oral drug AZD0780 and Verve Therapeutics' gene

therapy, which is expected to be used in combination with other

drugs.