Sanofi-Aventis SA’s experimental diabetes drug lixisenatide, given to volunteer patients once a day, was at least as effective as Eli Lilly and Co. and Amylin Pharmaceuticals Inc.’s twice-daily medicine Byetta in keeping blood-sugar levels in check, a study found.

The advanced study of 639 patients with the most common form of diabetes, known as Type 2, showed those taking the Sanofi drug also had fewer instances of hypoglycemia, a state of dangerously low blood sugar, Paris-based Sanofi said in a statement.

The findings could lead to more competition for Indianapolis-based Lilly, which markets Byetta outside the United States and co-markets it with Amylin in the U.S. The drug had worldwide sales of $796.5 million in 2009.

Diabetes occurs when the body doesn’t produce or properly use insulin, a hormone needed to convert sugar, starches and other food into the energy needed for daily life. Lixisenatide belongs to a class of drugs that imitate a hormone called GLP-1 to stimulate the pancreas to produce more insulin after meals. Both lixisenatide and Byetta are injections.

Sanofi trails Novo Nordisk A/S and Lilly in developing a GLP-1 product. Peter Welford, an analyst at Jefferies International Ltd., wrote in a note to investors Tuesday that he expects lixisenatide to have "blockbuster" sales. The full study will be released at a medical conference, the drugmaker said. Zealand Pharma A/S of Denmark developed lixisenatide from the spit of the Gila monster.

Byetta uses a synthetic version of a substance in Gila monster saliva.

Separately, Roche Holding AG said Tuesday that it’s stopping development of another GLP-1 treatment, taspoglutide, and returning rights to developer Ipsen SA.

After “extensive analysis,” the Switzerland-based company said it has decided to stop development of the medicine. Ipsen said it will sift through the Roche research and could seek another partner. The decision may mean the end of development for a drug that some analysts once predicted would have annual sales of more than $1.38 billion and compete with Byetta and Novo Nordisk’s Victoza.