(Adds further details, analyst's comment)
By Nikolaj Skydsgaard
COPENHAGEN, Sept 16 (Reuters) - Novo Nordisk's experimental injectable diabetes drug semaglutide reduced cardiovascular risk by 26 percent according to the keenly awaited results of a clinical trial released on Friday.
Semaglutide is the third diabetes drug to show such heart benefits, after Novo's Victoza injectable and Eli Lilly and Boehringer Ingelheim's Jardiance pill.
Shares in Novo Nordisk were up 1.7 percent at 310 crowns by 0730 GMT.
"These strong data suggest Novo will launch a bigger and longer cardiovascular impact study for semaglutide in order to show long-term benefits," Sydbank analyst Soren Lontoft said to Reuters.
The study also found that semaglutide caused an "unexpected higher rate" of retinopathy complications, such as blindness.
Because about half of deaths in people with diabetes are caused by heart disease, reducing the risk such as heart attacks and strokes is viewed as essential.
Novo announced in April that the so-called SUSTAIN 6 trial had significantly cut the risk of major adverse cardiovascular events, but the scale of the benefit was only disclosed this week at a meeting of diabetes experts in Munich.
Semaglutide, which is designed to be given once a week, belongs to a class of medicines known as GLP-1 analogues that increase the body's insulin production when blood sugar levels are raised.
The excessive blood sugar levels that come with diabetes can cause long-term damage to blood vessels, increasing the risk of cardiovascular disease such as heart attack, heart failure or stroke.
Novo intends to file for regulatory approval of semaglutide in the United States and Europe in the last quarter of 2016. Consensus analyst forecasts suggest annual sales could reach $2.2 billion in 2022.
Semaglutide, which has proved highly effective in reducing glucose levels in patients with type II diabetes, is viewed as a pivotal product for Novo, which competes in the GLP-1 market against several rivals including Eli Lilly's Trulicity.
"Semaglutide is one of the drugs which is going to drive growth for Novo Nordisk in the coming years - their entire GLP-1 business in fact," Lontoft said.
The Danish company is also working on an oral version of semaglutide, which would be the first GLP-1 to be given as a pill rather than an injection.
(Editing by Greg Mahlich)