Johnson & Johnson announced its $2 billion acquisition of Ambrx Biopharma, a drugmaker specializing in cancer treatment. Ambrx focuses on antibody-drug conjugates (ADCs), which target and kill cancer cells while minimizing damage to healthy tissue. This move follows similar investments in ADCs by other major drugmakers. The acquisition will help J&J fill a revenue gap that is expected in 2025, when its top-selling drug Stelara faces generic competition. The deal is expected to close in the first half of 2024. Share prices for Ambrx nearly doubled in premarket trading.