Eli Lilly has partnered with San Francisco, Calif.-based Lycia Therapeutics to create drugs capable of attacking disease-causing proteins.

Under the deal, Lilly will pay Lycia $35 million upfront, with Lycia eligible to receive more than $1.6 billion in additional milestone-based payments, as well as tiered royalties on sales.

The companies will use Lycia’s lysosomal targeting chimera platform to develop new medicines for as many as five protein targets across different Lilly research areas, such as immunology and pain. The drugmakers hope the platform will yield several types of new therapeutics, including antibodies and small molecules.