Sandoz launches rival version of AbbVie's arthritis drug Humira

(Reuters) - Swiss drugmaker Sandoz said on Saturday it had launched a biosimilar version of AbbVie Inc's big selling arthritis treatment Humira, adding to U.S. competition for the drug that started in January.

The Novartis-owned company said its drug, Hyrimoz, will be priced at a 5% discount off Humira’s current list price of $6,922 per month, but that it was also offering an unbranded version of Humira at an 81% discount.

Healthcare experts have said that drugmakers will probably launch their Humira biosimilars with small discounts to appeal to pharmacy benefit managers, which take some of their fees as a percentage of the discounts they negotiate on behalf of their customers - large employers and health insurance plans.

The lower-priced version may attract healthcare systems that act as both an insurer and a provider and typically do not seek after-market discounts, as pharmacy benefit managers do.

Biosimilars are developed to work like an original, branded biotech drug, but are not necessarily exact copies, like traditional generic medicines, because they are cultivated in living cells.

Rival Amgen Inc was the first to launch a biosimilar of Humira earlier this year, which debuted at a 5% and 55% discount to Humira, depending on who was purchasing.

At least nine copies of Humira, which also treats conditions like ulcerative colitis and psoriasis, from companies including Pfizer Inc and South Korea's Celltrion are expected to be available in the United States by the end of the year.

(Reporting by Patrick Wingrove; Editing by Edwina Gibbs)