* Lantus shows modest effect on atherosclerosis in study
* Fish oil medicine has no effect
MUNICH, Aug 27 (Reuters) - Sanofi's top-selling insulin treatment Lantus may slow the build-up of artery-clogging deposits, although the benefits are modest, researchers said on Monday.
Lantus, which generated worldwide sales of nearly 4 billion euros ($5 billion) last year, earlier failed to show overall heart benefits in a large clinical study.
However, a section of that trial suggests it could slow the thickening of arteries - a process known as atherosclerosis - that can raise the risk of heart attack and strokes, Dr Eva Lonn of Canada's McMaster University told the European Society of Cardiology annual meeting.
Lonn said Lantus appeared to slow the progression of atherosclerosis by 11 percent over five years in her analysis of 1,100 patients with early type-2 diabetes and cardiovascular risk factors.
That result, which was main goal of the study, fell short of being statistically significant but secondary endpoints, looking at thickness at specific points of the carotid artery, did show a significant benefit for patients on Lantus.
By contrast, giving patients Omacor/Lovaza - a fish oil medicine developed by Norway's Pronova Biopharma and sold by GlaxoSmithKline and Abbott Laboratories - had no effect on atherosclerosis in the study.
"The signal is there but it is a little bit weak," Dr Alfred Bove of the Temple University School of Medicine in Philadelphia, who was not involved in the research, said of the Lantus finding.
"It fits with the concepts we have ... I think there is probably some process that goes wrong when people have consistently high blood glucose that causes deposition in the blood vessels."
Competition is ramping up in the multibillion-dollar market for long-lasting insulins like Lantus, adding to pressure on Sanofi to find key selling points for its market-leading product. Novo Nordisk and Eli Lilly are both lining up new products to challenge Lantus.
($1 = 0.7989 euros) (Reporting by Ben Hirschler; Editing by Mark Potter)