Amgen, Astra's brodalumab meets goals in Phase 3 psoriasis study

May 9 (Reuters) - An antibody drug under development by Amgen Inc and AstraZeneca Plc met the goals of a Phase 3 study in patients with moderate-to-severe plaque psoriasis, the companies said on Friday.

The 661-patient trial of brodalumab met all primary and secondary endpoints for both of the evaluated doses, they said. It showed that 83 percent of patients given the highest dose, and 60 percent of patients on a lower dose, achieved at least a 75 percent reduction in disease severity after 12 weeks, compared with about 3 percent of placebo patients.

Psoriasis, an immune system-related disease that causes an overproduction of skin cells resulting in patches of thick inflamed skin covered with silvery scales, affects 125 million people worldwide and about 7.5 million Americans, according to the National Psoriasis Foundation.

Brodalumab is designed to reduce inflammatory signaling by blocking the binding of interleukin-17 ligands to cell receptors.

Amgen and AstraZeneca, which has spurned recent takeover offers from Pfizer Inc, are also conducting two head-to-head trials comparing brodalumab to Stelara, also known as ustekinumab, a psoriasis treatment sold by a unit of Johnson & Johnson.

Side effects in the Phase 3 brodalumab trial included head colds, upper respiratory tract infection and headache. Serious side effects occurred in 1.8 percent of patients in the high-dose group, 2.7 percent of patients in the low-dose group and 1.4 percent of the placebo group.

(Reporting by Deena Beasley in Los Angeles; editing by Matthew Lewis)