Pivotal findings for the off-the-shelf cell therapy surpassed William Blair’s expectations and sent Allogene Therapeutics’ stock up more than 50% in pre-market trading Monday morning.
Allogene Therapeutics’ cell therapy has aced an interim lymphoma test, clearing residual disease in 41.6% more patients compared to those in an observational arm of the pivotal trial.
The findings for the off-the-shelf experimental treatment surpassed the expectations of William Blair analysts and sent Allogene’s stock up more than 50% in pre-market trading Monday morning. If the study scores its main goal of event-free survival, the California biotech plans on using the data to request FDA approval.
The highly anticipated findings include data from 24 patients with large B cell lymphoma (LBCL), half of whom were given Allogene’s cema-cel as a consolidation therapy, designed to eliminate residual disease after initial treatment administration.
The futility analysis demonstrated a 58.3% measurable residual disease (MRD)–clearance rate among the 12 patients receiving cema-cel at 45 days compared to a 16.7% MRD-clearance rate for the 12 patients in the observation arm.
The efficacy seen in the data “nails” William Blair’s bull case scenario of 40% MRD-clearance, the firm wrote in a Monday note. The new findings also outperform previously stated expectations from Allogene’s leadership team of up to a 30% clearance difference.
Furthermore, the allogeneic CAR T was tied to a 97.7% reduction in plasma circulating tumor DNA (ctDNA), while ctDNA levels rose by 26.6% in the wait-and-watch group. Typically, higher ctDNA levels are associated with more advanced disease.
The interim findings, stemming from the Phase 2 ALPHA3 trial, also found cema-cel to be “very well-tolerated,” with zero cases of cytokine release syndrome or immune effector cell–associated neurotoxicity syndrome (ICANS) occurring, according to Allogene.
Rates of low-grade infections were similar across treatment groups, though half of patients in the investigational arm experienced other neurologic events outside of ICANS—such as headache or dizziness—compared to only one patient in the observational cohort. That being said, all neurologic events were low-grade, with William Blair saying the events were likely related to preconditioning chemotherapy.
Overall, William Blair believes the futility analysis findings “significantly increases the probability of success in a blockbuster market opportunity.” As a first-line consolidation treatment, cema-cel could represent about a $2.5 billion to $3.5 billion market opportunity, Allogene estimates.
Looking forward, Allogene anticipates sharing interim data on ALPHA3’s primary endpoint of event-free survival in mid-2027 and a primary analysis the following year. The open-label trial is expected to recruit 220 patients across more than 60 sites.
Allogene’s approach is innovative in the fact that it elevates the use of MRD testing for lymphoma patients in hopes of ultimately reducing relapse risk. According to Allogene, ALPHA3 is the first randomized trial in LBCL evaluating whether MRD-guided intervention before relapse can eliminate residual disease.
“These early results represent an important step toward redefining first-line large B cell lymphoma management,” Allogene CEO David Chang said on a Monday investor call.
“Today, many patients are simply observed after first-line therapy, despite remaining at high risk of relapse, and by the time relapse occurs, disease may be more difficult to control,” the CEO explained, adding that he believes cema-cel has the potential to intervene earlier.
“Our mission is to unlock the transformative potential of CAR-T through our allogeneic platform,” Chang said. “At its core, that mission is about democratizing cell therapy, expanding patient access, simplifying delivery for physicians and treatment centers, and optimally moving CAR-T earlier in the treatment paradigm where it may have the greatest impact.”
About a third of patients enrolled in ALPHA3 are receiving treatment in community cancer centers, delivery that Allogene believes is conducive to broad adoption.
