Polyphor AG temporarily discontinued two late-stage studies of murepavadin in patients with hospital-acquired pneumonia because of incidents of acute kidney injury that were higher than expected.

Acute kidney injury is a sudden episode of kidney failure or damage that can happen within a few hours or a few days.

Switzerland's Polyphor was comparing POL7080, or murepavadin, with antibiotics in two phase 3 studies, Prism-MDR and Prism-UDR. Hospital-acquired pneumonia occurs in patients after admission to a hospital for at least 48 to 72 hours and is usually caused by a bacterial infection, rather than a virus.

Polyphor had expected kidney injury incidences in the range of 25% to 40%. However, it halted the trials after 56% of the patients in the murepavadin arm of the Prism-MDR trial experienced kidney injuries. The company will provide an update on both studies in July after all data is available and reviewed.

Polyphor develops drugs that address antibiotic resistance and enhance therapy outcomes in cancer.