Adult Acute Lymphoblastic Leukemia
Adult B-ALL (acute lymphoblastic leukemia) is an aggressive type of leukemia characterised by the presence of too many B lymphocytes in the bone marrow and peripheral blood. Without treatment adult ALL usually progresses very rapidly. Prognosis for patients based on current treatments is very poor.
Combination chemotherapy enables 90% of adult patients to enter complete remission, but only 30-40% of these patients will achieve long term remission. The median overall survival is < 1 year in r/r adult ALL.
The only redirected T cell therapies for adult patients are blinatumomab and brexucabtagene autoleucel. These therapies are highly active, but achieving long term remissions remains challenging. Patients are generally more fragile with co-morbidities, yet CAR T toxicities in this setting have been notable with high incidences of severe CRS and cases of fatal neurotoxicity.
A significant unmet need remains for adult ALL patients. A successful therapy requires high level of activity and sustained persistence paired with good tolerability.
Adult ALL is a significant unmet medical need
Median OS <1 year
Obe-cel in adult ALL
Data from the FELIX Phase 1b and ALLCAR19 Phase 1 studies in relapsed / refractory adult ALL patients shows a high levels of complete responses across both studies in the absence of high grade (≥Grade 3) cytokine release syndrome (CRS) and with low rates of immune effector cell-associated neurotoxicity syndrome (ICANS).
In the ALLCAR19 study where longer term follow up data is available, we continue to observe sustained responses with obe-cel without the requirement for subsequent therapy. The event free survival, a measure of long term efficacy, is 46% at 24 months, with some patients approaching up to 42 months of durability. These data support the curative potential of obe-cel as a standalone therapy in r/r adult ALL patients.
Obe-cel, is currently being trialed in the potentially pivotal FELIX study for adult ALL. In this indication, obe-cel has been granted orphan drug designation by the FDA, PRIME designation by EMA and ILAP designation by the MHRA. Autolus expects to present data from the Phase 2 portion of the FELIX study in 2022.