Celltrion said Wednesday that it has signed a business agreement with WuXi XDC, a Chinese company specializing in antibody-drug conjugates (ADCs), to strengthen ADC drug development and to begin developing drugs for contract development and manufacturing organizations (CDMOs).

WuXi XDC, a joint company between WuXi Biologics and WuXi STA, provides contract research and development manufacturing organization (CRDMO) services focused on ADCs and bioconjugates.

Celltrion previously signed a CDMO agreement with Wuxi in December last year to develop a linker-payload synthesis process for its ADC drug pipeline.

Under the contract, Wuxi will be responsible for the development of the linker-payload synthesis process and the production of current good manufacturing practice (cGMP) ADC drugs for phase I clinical trials.

The latest accord is designed to strengthen the strategic partnership by expanding the scope of ADC pipeline development and enhancing mutual benefits.

Under the agreement, the companies will also continue discussions on expanding CDMO distribution of ADCs.

Celltrion expects that this agreement, which follows the previous CDMO agreement for ADC  development, will enable Celltrion to quickly and stably advance the development of ADCs.

In addition, Celltrion is actively developing ADCs in collaboration with various domestic and international companies such as Iksuda Therapeutics, a British ADC developer, and Pinotbio, a Korean biotech, to develop ADC drugs targeting solid tumors.

Celltrion has a total of six ADC drug pipelines under development, and as all projects are progressing smoothly, the company plans to gradually disclose development results and strategies for each project.

"Celltrion will continue to seek various partnerships to secure ADC drugs through in-house development and collaboration," a Celltrion official said. "We will continue to do our best to develop innovative drugs including ADCs and secure differentiated competitiveness."