Telix Pharmaceuticals has agreed to buy a big radiopharmacy network in the United States as part of a $1 billion acquisition spree over the past two years designed to establish it as a major supplier and distributor of medicines used to treat cancer.

The cancer diagnostics specialist said it would acquire Florida-based RLS for $388 million as part of a strategy to become a dominant player in the market for drugs that contain radioactive forms of chemical elements called radioisotopes.