Isis Pharmaceuticals has commenced a Phase I study to assess ISIS-APOARx for the treatment of atherosclerosis.

Around 56 healthy volunteers will participate in the blinded, placebo-controlled, dose-escalation study designed to evaluate the safety, tolerability and pharmacokinetics profile of both single and multiple doses of ISIS-APOARx.

ISIS-APOARx is an antisense drug targeting apolipoprotein(a), which is believed to attach to an LDL-C particle in a complex termed lipoprotein(a), or Lp(a), and aids in plaque formation in the arteries.

High levels of Lp(a) may lead to increased risk of atherosclerosis, coronary heart disease, heart attack and stroke.

ISIS-APOARx works by inhibiting apolipoprotein(a) production, thereby reducing Lp(a) levels.

Isis development vice president and chief medical officer Dr Walter Singleton said Lp(a) is believed to be an independent risk factor for coronary heart disease.

"Although Lp(a) can be measured during a routine lipid blood panel, the lack of drugs that effectively lower Lp(a) have made treating patients with high Lp(a) levels difficult," Singleton said.

"Because elevated Lp(a) is an inherited genetic condition, patients are unable to adequately control their Lp(a) levels through diet or lifestyle changes.

"By inhibiting the production of apolipoprotein(a), ISIS-APOARx is designed to reduce the levels of Lp(a), thereby offering a unique and specific approach to treating patients who have high cardiovascular risk due to high Lp(a) levels."

Image: Microphotography of arterial wall with calcified (violet colour) atherosclerotic plaque (haematoxillin and eosin stain).