Lexeo Therapeutics (LXEO) investor relations material

Lead program and pipeline updates

• Lead program targets Friedreich's ataxia (FA) cardiomyopathy, now in a pivotal study with data expected in the second half of 2027.

• Recent acquisition expanded the FA pipeline to include brain-targeted frataxin delivery, complementing the cardiovascular approach.

• PKP2 arrhythmogenic cardiomyopathy gene therapy program will have new data in late 2026, with promising early efficacy and safety results.

• The company is prioritizing both cardiac and neurologic FA programs, aiming for comprehensive disease coverage.

• Pipeline prioritization update and next IND for neurologic FA assets are planned for early and late 2027, respectively.

Clinical trial design and rationale

• The pivotal FA trial (LX2006) enrolls patients with significant cardiac hypertrophy, using a 15% effect size as the primary endpoint.

• Natural history study sites overlap with pivotal trial sites, facilitating patient transition; neutralizing antibodies are a key eligibility factor.

• Secondary endpoints include cardiac biomarkers (troponin), patient-reported outcomes (KCCQ), and neurologic function (mFARS).

• Phase I/II data showed a 28% effect size and durable improvements in both cardiac and neurologic measures.

• The label is expected to cover a broad FA cardiomyopathy population, not limited to those with severe hypertrophy.

PKP2 arrhythmogenic cardiomyopathy program

• Early data showed >20% improvement in nonsustained ventricular tachycardia and 14% in premature ventricular contractions at six months.

• Longer follow-up (nine months) showed a 65% improvement in NSVT, with further data at 12 months expected in late 2026.

• The biological rationale supports increasing efficacy over time as the desmosomal complex reforms.

• Safety profile is strong, with no gene therapy-related serious adverse events at high doses.

• Regulatory and clinical data updates are planned for Q4 2026, with RMAT designation received.