Lexeo Therapeutics (LXEO) said Monday that arrythmia burden stabilized or improved in most participants of its phase 1/2 trial of LX2020 in patients with PKP2-associated arrhythmogenic cardiomyopathy.

The investigational gene therapy was "generally well tolerated" across 10 dosed participants, with no significant complement activation and manageable liver function tests elevations that resolved without any complication or hospitalization, according to Lexeo.

The company also said treatment led to strong transduction and increased PKP2 protein expression across participants with dose-dependent response.

Lexeo said 12-month data from all high-dose participants is expected in Q4, with regulatory engagement planned within the year.

Shares of Lexeo Therapeutics fell more than 34% in recent trading Monday.

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