Shares of biotech companies involved in the development of monoclonal antibody cancer therapies were moving all over the place on Friday. Both U.S.-based Summit Therapeutics (SMMT -36.19%) and BioNTech (BNTX -15.40%) were down significantly, plunging 36.1% and 15.4%, respectively, in Friday's trading.The severe moves were likely related to a Chinese rival in the PD-1/VEGF bispecific antibody area, Akeso (AKES.F 2.96%), receiving FDA approval for a cancer drug that utilizes similar technology, as well as an ...