There was more good news from Amgen this week after another batch of positive late-stage data for its novel cholesterol buster put it ahead in the race to get the first PCSK9 inhibitor to market.

The latest in a stream of successful Phase III trials of evolocumab, an injectable monoclonal antibody that inhibits PCSK9 (proprotein convertase subtilisin kexin type 9), met its primary endpoint of percent reduction from baseline at week 12 in low-density lipoprotein cholesterol (LDL-C), also referred to as 'bad' cholesterol.

The Phase III TESLA trial evaluated the safety, tolerability and efficacy of evolocumab compared to placebo in 49 adults and adolescents (12 to less than 18 years of age) with homozygous familial hypercholesterolemia - a rare and devastating disease characterised by extremely high LDL-C levels - who were on a stable dose of statin therapy and other lipid-lowering medication. 

Specific data were not released at this time, but Sean Harper, executive vice president of Research and Development at Amgen, said the firm is "encouraged" by the results of the trial, "the first Phase III data of a PCSK9 inhibitor in homozygous familial hypercholesterolemia patients, which suggest evolocumab may offer a new treatment option for these patients who currently have significant unmet medical needs".

On the safety side, the risk of adverse events was generally balanced between patients taking evolocumab alongside statins and those taking statins alone, Amgen noted, with the most common adverse events in the evolocumab group including upper respiratory tract infection and gastrointestinal inflammation.

The race to get the first PCSK9 inhibitor - which increase the number of LDL receptors on liver cells and so boost LDL clearance from the blood - to market is heating up, with drugmakers such as Pfizer (RN-316) and Sanofi/Regenron (alirocumab) grappling for the first slice of a highly lucrative market.

Up to 80% of high risk patients are still not reaching their cholesterol treatment goals using statin therapy, highlighting the need for new therapies, and analysts believe that the PCSK9 inhibitors could rake in sales of around $3-$4 billion each.