By Ransdell Pierson
March 17 (Reuters) - Amgen Inc said its experimental new type of cholesterol-fighting drug met the primary goal of a late-stage trial by slashing "bad" LDL cholesterol levels in patients with a genetic tendency towards high levels of the artery-clogging fat.
Amgen said on Monday patients given its injectable drug evolocumab once a month, on top of standard daily statin treatments, showed "clinically meaningful" improvement compared with taking statins alone after 12 weeks of treatment. The drug is also known as AMG-145.
The Phase 3 study, called TESLA, involved 49 adult and adolescent patients with a rare condition called homozygous familial hypercholesterolemia. The condition, seen in about one in a million individuals, can cause a four-fold increase in levels of LDL cholesterol, greatly raising the risk of heart disease.
Evolocumab works by blocking PCSK9, a naturally occurring protein that keeps LDL levels elevated in the bloodstream.
Other drugmakers, including Pfizer Inc, and a partnership between Regeneron Inc and Sanofi, are racing with Amgen to complete trials of potentially lucrative anti-PCSK9 antibodies.
"You could have two or three drugs here, each with upwards of $3 billion to $4 billion in annual sales," said Richard Purkiss, an analyst with Atlantic Equities.
The PCSK9 inhibitors are one of the most closely followed new classes of medicines, Purkiss said, even though they will probably not be prescribed for the average patient with high cholesterol.
If approved, "they would be used mainly for very high-risk patients, who have frustratingly high LDL despite statin treatment," he said.
Purkiss said Regeneron and Sanofi had been ahead of the pack in terms of completing clinical trials, but that Amgen's trials had picked up speed and its drug could be the first to market.
In Amgen's now-completed TESLA study, the safety risk was similar between those taking evolocumab in combination with statins, and those taking statins alone, Amgen said, with the most common adverse events including upper respiratory tract infection, gastrointestinal inflammation and stuffy nose.
Data from the trial will be presented at a future medical conference, Amgen said. The world's largest biotechnology company noted that favorable results have previously been reported in five other Phase III trials of its experimental medicine, which involved different populations.
They have included trials among mainstream populations whose high cholesterol is not due to serious genetic causes, as well as trials among those who cannot tolerate statins and instead take a different type of cholesterol fighter called Zetia (ezetimibe) from Merck & Co.
In mid-stage studies, evolocumab has cut LDL levels by as much as 60 percent more than with statins alone.
Such results have bolstered faith among doctors and industry analysts that the drug and other PCSK9 inhibitors might be a good option for patients who are unable to reach target LDL levels with statins and other standard treatments.
Amgen shares were up 1.8 percent in midday trading on the Nasdaq, amid a 1.5 percent gain for the NYSARC Biotech Index .