By Chris Wack

Tectonic Therapeutic shares doubled, to $56.80, after the company said it saw positive interim data from a Phase 1b acute hemodynamic clinical trial of its lead product candidate, TX45, a long-acting, Fc-relaxin fusion protein.

Shares hit their 52-week high of $58.62 earlier in the session, and are now up 303% in the past 12 months.

The biotechnology company said the interim data showed that a single intravenous dose of TX45 resulted in meaningful improvements in both left ventricular function and pulmonary hemodynamics in patients with group 2 pulmonary hypertension in heart failure with preserved ejection fraction.

In the trial, TX45 was well tolerated, with no serious or severe adverse events, discontinuations, infusion reactions or drug-related adverse events.

The Watertown, Mass., company said that in the overall study population, TX45 achieved a 17.9% reduction in pulmonary capillary wedge pressure, an endpoint known to correlate with exercise capacity, morbidity and mortality in patients with heart failure.

The interim results from the Phase 1b open label clinical trial are based on 16 of 19 enrolled patients with PH-HFpEF, with the remaining 3 patients currently completing Part A of the protocol.

Write to Chris Wack at chris.wack@wsj.com

(END) Dow Jones Newswires

January 30, 2025 12:44 ET (17:44 GMT)

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