AstraZeneca has reported dosing of the first subjects in the Phase III IRIS clinical trial of Saphnelo (anifrolumab) in patients with lupus nephritis (LN).

The two-year, multicentre, multinational, randomised, double-blind, placebo-controlled trial intends to enrol up to 360 subjects of the age 18 to 70 years.

Assessing the safety and efficacy of anifrolumab compared to placebo when given along with standard therapy comprising mycophenolate mofetil and glucocorticoids in adults with active Class III or IV LN is the goal of the trial.

A fully human monoclonal antibody, anifrolumab attaches to subunit 1 of the type I interferon (IFN) receptor, hindering type I IFN’s activity.

AstraZeneca BioPharmaceuticals R&D executive vice-president Mene Pangalos said: “Lupus nephritis continues to represent a significant burden to patients worldwide. 

“Following the approval of anifrolumab as the first new treatment for systemic lupus erythematosus in over a decade, the start of our IRIS Phase III trial in lupus nephritis is another important step forward in our ambition to bring anifrolumab to more patients with diseases where type I interferon is a central driver.”

Saphnelo is currently approved in the US, Japan, Europe and Canada to treat moderate to severe systemic lupus erythematosus (SLE).

According to data from the proof of concept, dose-finding Phase II TULIP-LN1 trial of anifrolumab published in February this year, a higher dose of the antibody offered clinically meaningful numeric improvements across various secondary and exploratory endpoints compared to placebo. 

All subjects in the trial had received standard therapy.

The change in a measure of kidney function at week 52 for combined anifrolumab versus placebo arms was the primary endpoint of the trial, which was not met. 

Herpes zoster, urinary tract infection and influenza were reported to be more common adverse events seen in the combined anifrolumab versus placebo arms.

The latest development comes after AstraZeneca dosed the first subject in the Phase III PACIFIC-9 trial of durvalumab plus monalizumab or its oleclumab in unresectable, Stage III non-small cell lung cancer patients.