Amgen is the latest drugmaker to present data for a cholesterol drug that blocks the PCSK9 pathway.

Phase I data presented at the American Heart Association meeting in Orlando showed that a single dose of Amgen's AMG145, a monoclonal antibody, reduced levels of low density lipoprotein  or 'bad' cholesterol by up to 64% compared to placebo in healthy people. The study randomised 56 people aged 18-45 who did not have elevated cholesterol levels and were not taking other drugs, to receive a single injection or intravenous administration of one of five doses of AMG145 or placebo.

Amgen noted that with increasing doses of AMG145, blood tests revealed less of the active form of PCSK9, lower levels of bad cholesterol, total cholesterol and apo-B (the primary protein component of bad cholesterol). It also showed no effect on triglycerides, high density lipoprotein ("good" cholesterol) or a protein associated with good cholesterol.

Clapton Dias, medical sciences director of clinical pharmacology and early development at Amgen, noted that PCSK9 is the first target in lipid metabolism to be inhibited using a monoclonal antibody "and it appears to be a promising way to lower [LDL] cholesterol". Speaking about the trial, he added that the more PCSK9 was lowered, "the more bad cholesterol levels went down. With higher doses, bad cholesterol stayed lower for a longer period."

Amgen is now conducting a similar study among adults who are already taking statins to control their cholesterol.

The US biotech major has some ground to make up on Sanofi and Regeneron's REGN727, the firm's antibody which also blocks which also blocks the PCSK9 pathway. Last week, the firms presented positive Phase II data from two studies, one of which involved combining the drug with Pfizer's Lipitor (atorvastatin).

Other companies testing anti-PCSK9 treatments include Pfizer, Merck & Co and Bristol-Myers Squibb.

Amgen selling debt in Europe

Meantime, Amgen says it is meeting with European investors this week with a view to raising $1-$1.5 billion in euro and sterling debt.

The cash will be used to fund its recently-announced stock buyback programme and for general corporate purchases. Amgen is repurchasing $5 billion of shares and last week sold $6 billion of debt.