Feb 13 (Reuters) - Johnson & Johnson ( JNJ ) and partner

Sanofi will stop a late-stage trial of an experimental

vaccine to prevent infections caused by the E.coli bacteria due

to a lack of sufficient efficacy, the companies said on

Thursday.

No safety issues related to the experimental vaccine were

identified after an independent review, J&J said and added it

was conducting follow-ups for participants currently enrolled in

the trial.

Sanofi said it has recorded a charge of $250 million related

to the discontinued trial in its fourth-quarter results and

added it will not impact its 2025 forecast provided in January.

Jean-François Toussaint, who heads Sanofi's vaccine research

and development efforts, said the companies will try to

understand the factors behind the lack of sufficient efficacy of

the shot and will share further analysis of the data once

available.

The late-stage study began in June 2021 and enrolled adults

aged 60 years or older who were in stable health but had a

recent history of a urinary tract infection. It was conducted at

over 250 sites across five continents.

The companies were testing the safety and efficacy of a

single dose of the experimental shot, ExPEC9V, in preventing

sepsis and blood infections caused by E.coli.

While most strains of E.coli are harmless, some can cause

serious food poisoning, diarrhea and abdominal cramps.

Last year, 104 people fell sick and 34 were hospitalized due

to an outbreak caused by the O157:H7 strain that was linked to

the McDonald's Quarter Pounder hamburgers.