Can Early Partnerships Fix the ADC Bottleneck?

SK pharmteco and Lotte Biologics signal early plans to rethink how complex ADC therapies could be made at scale

10 Feb 2026

A quiet agreement, rather than a new molecule, hints at where cancer drugmaking is heading. SK pharmteco and Lotte Biologics have signed a letter of intent to explore working together on the manufacture of antibody drug conjugates, or ADCs, a fast growing but awkward class of cancer therapies. The pact creates no joint venture and promises no factories. Its purpose is preparatory. That alone says something about the pressures ahead.

ADCs marry two very different worlds: large, delicate antibodies and tiny, extremely potent chemical payloads. The result can be powerful. Several ADCs have recently won approval, and hundreds more sit in global pipelines. Yet their manufacture is hard to scale. It demands tight containment, careful timing and a handoff between biologics and high risk chemistry that few firms can manage smoothly.

This has created an imbalance. Innovation in oncology is racing ahead, while manufacturing capacity lags behind. Developers, once content to stitch together services from multiple contractors, are now worrying about complexity, delays and unclear accountability as drugs move into late stage trials. They want fewer seams in the process.

The proposed tie up reflects that shift. Under the LOI, SK pharmteco’s experience with drug linker components would be assessed alongside Lotte Biologics’ growing network for biologics production. The aim is to see whether a more integrated platform could be built in time, one that links antibody production and conjugation more closely, and eventually supports commercial supply.

Competition among contract manufacturers is sharpening as a result. Only a small group can plausibly offer both large scale biologics and the specialised chemistry ADCs require. Those that can position themselves early may gain an advantage, even if today’s agreements are mostly about learning rather than building.

Much remains uncertain. Standards must be aligned, investments justified and demand proved. But the direction is clear. As ADCs move from promise to pipeline staple, the industry is discovering that manufacturing, long an afterthought, may determine which cancer drugs actually reach patients.