Allogene Therapeutics (ALLO) Study result summary

Interim efficacy results

• Cema-cel achieved a 58.3% MRD clearance rate at Day 45 versus 16.7% for observation, a 41.6% absolute difference, surpassing the clinically meaningful benchmark of 25-30%.

• Median plasma ctDNA decreased by 97.7% in the cema-cel arm at Day 45, while the observation arm saw a 26.6% median increase.

• Early MRD clearance supports cema-cel as a novel strategy for high-risk LBCL post first-line therapy.

• The majority of patients had high-risk disease features, with the cema-cel arm showing numerically more advanced disease.

• Both arms had similar rates of partial remission and use of high-intensity first-line regimens.

Safety and tolerability

• No cases of CRS, ICANS, GVHD, or treatment-related serious adverse events were observed in the cema-cel arm.

• Most cema-cel patients were managed entirely in outpatient settings, with only two brief hospitalizations unrelated to treatment.

• Low-grade infections and neurologic events were observed, with no grade ≥3 events in the cema-cel arm.

Study design and patient access

• ALPHA3 is an open-label, randomized phase II trial enrolling ~220 LBCL patients in CR/PR at end of 1L therapy with MRD positivity, randomized 1:1 to cema-cel or observation.

• The study is being conducted at over 60 sites, with about 33% of screening and infusions in community centers, including sites new to CAR T therapy.

• Cema-cel is administered as a single dose following lymphodepletion, with MRD samples collected at multiple timepoints.

• Interim futility analysis included 24 patients (12 per arm) with MRD assessed at Day 45.

• The trial is powered to detect a 50% reduction in risk of disease progression, new anti-lymphoma treatment, or death, with event-free survival as the primary endpoint.