NEW BRUNSWICK, N.J. (AP) — Johnson & Johnson said Friday it completed its $893.7 million acquisition of Cougar Biotechnology Inc., a development stage company that is testing a potential vaccine for prostate cancer. Johnson & Johnson said about 20.1 billion shares of Cougar were tendered in favor of its buyout offer, which represented 95.9 percent of the company’s outstanding common stock. Johnson & Johnson agreed to buy Cougar in May and antitrust regulators signed off on the deal in June. Los Angeles-based Cougar is conducting two late stage clinical trials of abiraterone acetate as a treatment for prostate cancer. It is also testing the drug against breast cancer, and has four other potential cancer drugs in various stages of clinical and preclinical development. Cougar is now a wholly owned subsidiary of Johnson & Johnson, and will work with the Ortho Biotech Oncology Research and Development unit.