South Korea's biopharmaceutical company Celltrion announced Monday that the company will cooperate with the US biotech firm Rani Therapeutics to develop an oral version of the Humira biosimilar CT-P17.

CT-P17, also known as Yuflyma, is a high-concentration, low-volume and citrate-free biosimilar of Humira, an injectable treatment for rheumatoid arthritis and other autoimmune conditions, developed by AbbVie. Celltrion received the US Food and Drug Administration's approval for the injectable adalimumab biosimilar in May, as well as the European Medicines Agency approval in 2021.

To co-develop the oral formulation of the Humira biosimilar, named RT-105, Celltrion signed a contract with Rani Therapeutics, the same company Celltrion signed another contract in January to develop RT-111, an oral formulation of Celltrion's Stelara biosimilar CT-P43.

"Celltrion expects the latest collaboration with Rani will help the company increase its footing in the adalimumab market," an official from Celltrion said. The adalimumab market is currently estimated at around $21.2 billion, with over 87 percent ($18.62 billion) of the sales coming from the US, Celltrion added.

Under the contract, Celltrion will supply Rani with CT-P17 required for the development of the oral version of the biosimilar.

In the future, Celltrion can have priority negotiation rights for global development and sales of the oral adalimumab biosimilar, depending on the results of the phase 1 clinical trials for the oral formulation.