Adam Feuerstein is a senior writer and biotech columnist, reporting on the crossroads of drug development, business, Wall Street, and biotechnology. He is also a co-host of the weekly biotech podcast The Readout Loud and author of the newsletter Adam’s Biotech Scorecard. Tenax Therapeutics on Monday reported negative results from a late-stage clinical trial evaluating an experimental treatment for a type of heart failure associated with high blood pressure in the lungs. Shares of the biotech company plunged 84% to $2 in early trading. The difference was not statistically significant, failing to achieve the study’s primary efficacy goal, the company said.