712 Background: The MORPHEUS platform comprises multiple Ph Ib/II trials to identify early
efficacy signals and safety of treatment (tx) combinations across cancers. Due to the immune-
mediated effects of BL-8040, a high-affinity antagonist for CXCR4, it was tested with atezo
(anti-PD-L1) in pts with advanced/metastatic (m) PDAC and GC. Methods: In 2 separate
randomized trials, pts with mPDAC or advanced/mGC who progressed on 1L chemo
received either atezo+ BL-8040 (BL-8040 1.25 mg/kg SC D1-5, then BL-8040 1.25 mg/kg …

4540 Background: The MORPHEUS platform consists of multiple, global, open-label,
randomized Phase Ib/II trials designed to identify early efficacy signals and safety of
treatment (tx) combinations across cancers. Within MORPHEUS, atezo (anti–PD-L1) was
tested with PEGylated recombinant human hyaluronidase (PEGPH20), an anti–stromal and
extracellular matrix modulator, in patients (pts) with metastatic (m) PDAC or advanced/mGC.
Methods: In 2 separate randomized trials, eligible pts with 2L mPDAC or mGC received …