The US Food and Drug Administration (FDA) on Friday announced it had approved Amgen's Amjevita (adalimumab-atto), the first biosimilar version of AbbVie's best-selling biologic Humira (adalimumab).

In July, FDA's Arthritis Advisory Committee voted unanimously to support the approval. Despite the approval, FDA did not clear Amgen's biosimilar for all 10 of Humira's indications. According to FDA, both drugs share the following six indications:

• moderately to severely active rheumatoid arthritis;
• active psoriatic arthritis;
• active ankylosing spondylitis (an arthritis that affects the spine);
• moderately to severely active Crohn's disease;
• moderately to severely active ulcerative colitis; and
• moderate to severe plaque psoriasis.

However, FDA says that Amjevita is only indicated for juvenile idiopathic arthritis in patients four or older, while Humira is indicated to treat patients as young as two or older. And, unlike Humira, Amjevita is not approved to treat pediatric Crohn's disease, hidradenitis suppurativa or uveitis.

According to FDA, Amjevita is also required to display a boxed warning on its label over the increased risk of serious infections when taking the drug.

As with the three previous US biosimilar approvals, FDA says it has not approved Amjevita to be interchangeable with Humira.

The approval marks the fourth biosimilar approved under the Biologics Price Competition and Innovation Act's 351(k) pathway, which allows sponsors an abbreviated path to market by demonstrating their product is biosimilar to a reference product. In early August, AbbVie filed a lawsuit to stop the marketing of Amgen's biosimilar to Humira and it remains to be seen when Amjevita may hit the US market. Humira first one approval in 2002.

FDA