Tenax Therapeutics is trading 5.23% higher at $1.81, with available context pointing to biotech-sector strength rather than a clear company-specific catalyst. - Biotech was up 2.18% during the regular session. - An October 28 class-action announcement concerns allegations about earlier company statements and the TNX-103 program; it does not establish a reason for the current gain. - No trading-volume figure is available in the supplied price context.