US regulators have agreed to review Amgen's ABP 501, a biosimilar version of AbbVie's anti-inflammatory super-blockbuster Humira, with a decision on the drug's filing expected by September 25 this year.  

Humira (adalimumab) is an anti-TNF-_ monoclonal antibody approved across a range of inflammatory diseases, which pulls in sales of more than $13 billion a year making it the world's second best -elling drug.

ABP 501's filing is based on Phase III comparative efficacy and safety studies conducted in both moderate-to-severe plaque psoriasis and moderate-to-severe rheumatoid arthritis, which met their primary goals in showing clinical equivalence to Humira, while safety and immunogenicity were also comparable. 

Data to support the transition of adalimumab patients to ABP 501 are also being included in the submission, Amgen said. 

While pricing information isn't yet available, biosimilars are generally coming out at around 20%-30% less than their branded reference drugs, and thus have the potential to improve access to treatment.

"If approved, we believe ABP 501 could serve as an important additional approved therapeutic option for patients with chronic inflammatory conditions," said Sean Harper, R&D lead at the biotech giant.