Shares of dialysis services providers such as DaVita and German rival Fresenius Medical Care declined on Wednesday, after Novo Nordisk’s Ozempic showed early success in a trial to treat kidney failure in diabetes patients.

The Danish drugmaker said late on Tuesday it will stop its kidney outcomes trial almost a year ahead of schedule, based on a recommendation from the independent data monitoring board overseeing the study.

Frankfurt-listed shares of Fresenius fell 12.03% to 24.35 euros ($25.83) in normal trading hours and Davita fell 17.3% to $75.51 in premarket hours.

The early stop of the study could be negative for Fresenius as GLP-1 drugs like Ozempic could “potentially negatively impact” the size of the relevant patient population over time, Citi analyst Veronika Dubajova said in a note.

The early halt points to a “somewhat faster effect than we had previously contemplated,” Dubajova added.

GLP-1 drugs were developed to help control blood sugar in patients with Type 2 diabetes and are also used as weight-loss treatments.

Davita’s price-to-earnings ratio for the next 12 months, a common benchmark for valuing stocks, stood at 11.91 compared with Fresenius Medical’s 14.30.

Shares of U.S.-based Baxter International, which makes products used by dialysis therapy providers, also fell about 9% to $33.99 premarket.

As of Tuesday’s close, Davita shares were up 22.2% while Baxter shares were down about 27% so far this year.

($1 = 0.9428 euros)

(Reporting by Mariam Sunny in Bengaluru; Editing by Janane Venkatraman)