Inserting the Guidance System

BPX-101 is made from the patient's own monocytes in a six day process at a central cell processing laboratory. Monocytes, leukocytes and other types of white blood cell are collected in an outpatient leukapheresis procedure, a standard clinical procedure used for peripheral blood transplants or leukodepletion. It requires about half a day in an outpatient clinic, and recovery is generally quick and uneventful. Unlike some vaccine approaches, BPX-101 does not involve the challenging and invasive collection of primary tumor tissue.

The leukapheresis product is transported to the lab, where the monocytes are further purified by elutriation. The purified monocytes are incubated with cytokines that cause them to differentiate into dendritic cells by the fifth day, then the DeCIDe™ gene is delivered to the cells using an adenoviral vector, along with the PSMA antigen, which trains the cells to target PSMA-expressing cells. After overnight incubation the cells express the DeCIDe™ protein and can be activated by AP1903 to target PSMA. On the sixth day, the vaccine cells are washed, formulated, aliquoted into individual BPX-101 doses, and cryopreserved (frozen in liquid nitrogen). Unlike other approaches requiring one leukapheresis for each dose, a single batch of BPX-101 contains approximately eleven doses, sufficient for approximately one year of treatment.

Cell processing is performed under GMP conditions, in a functionally closed system developed and optimized expressly for BPX-101. Release testing, batch record preparation and review, and release for clinical use currently extend the total lead time to about 25 days, but this will be streamlined and reduced to less than 10 days in the near future.