Amgen and AstraZeneca Announce Positive Results from Phase III Study of Brodalumab (AMG 827) in Patients with Moderate-to-Severe Plaque Psoriasis

AstraZeneca and Amgen has announced that the Phase III AMAGINE-1TM study evaluating brodalumab in patients with moderate-to-severe plaque psoriasis met all primary and secondary endpoints for both evaluated doses.

Brodalumab is the only investigational treatment in development that binds to the interleukin-17 (IL-17) receptor and inhibits inflammatory signaling by blocking the binding of several IL-17 ligands to the receptor. Primary endpoints were patients achieving at least a 75% improvement from baseline in disease severity at week 12, as measured by the Psoriasis Area Severity Index (PASI 75), and patients achieving clear or almost clear skin at week 12 according to the static Physician Global Assessment (sPGA 0 or 1).

A significantly higher proportion of patients treated with brodalumab achieved a PASI 75 response (primary endpoint), as well as PASI 90 and PASI 100 responses at week 12 (secondary endpoints) compared to placebo. Results showed that 83.3% of patients in the 210 mg group and 60.3% of patients in the 140 mg group achieved PASI 75 responses compared to placebo (2.7%). Results also showed that 70.3% of patients in the 210 mg group and 42.5% of patients in the 140 mg group achieved PASI 90 responses compared to placebo (0.9%). Further, 41.9% of patients in the 210 mg group and 23.3% of patients in the 140 mg group achieved PASI 100 responses compared to placebo (0.5%). Of the 661 patients enrolled in this study, 46% reported prior biologic use and 28.7% weighed more than 100 kilograms (kg) at baseline (mean weight for the study population was 90.8 kg).

A PASI score is a measure of psoriatic plaque redness, scaling and thickness and the extent of involvement in each region of the body. Treatment efficacy is often measured by the reduction of PASI from baseline (i.e., a 75 percent reduction is known as PASI 75, a 90% reduction is known as PASI 90 and PASI 100 is total clearance of skin disease).

The most common adverse events that occurred during the placebo-controlled period in the brodalumab group (more than 5% of participants) were nasopharyngitis, upper respiratory tract infection and headache. Serious adverse events occurred in 1.8% of patients in the 210 mg group and 2.7% of patients in the 140 mg group compared to 1.4% for placebo during the placebo-controlled period.

“Data from the AMAGINE-1 study suggest that brodalumab may offer a new level of efficacy for patients with moderate-to-severe plaque psoriasis, a disease that affects more than 100 million people globally,” said Sean E. Harper, executive vice president of Research and Development at Amgen. “This is the first read-out from our Phase III psoriasis clinical programme and we look forward to obtaining additional Phase III data from our two head-to-head studies versus ustekinumab later this year.”