Checkpoint brake (PD-1):
Keytruda releases
Brake held
T cells armed, attacking
How a tumor biopsy becomes a personalized immune attack with the mRNA-4157 cancer vaccine plus Keytruda
tumor biopsy sequenced
patient-specific neoantigens
identified
1
mRNA-4157
Intismeran
2
personalized mRNA
Intismeran / mRNA-4157
encodes the neoantigens
3
tumor
residual melanoma cells
APC · dendritic cell
mRNA taken up
Keytruda
anti-PD-1
releases the
PD-1 brake
trained T cells
cytotoxic + memory
4
cytotoxic T cells attack
recurrence reduced vs
Keytruda alone
phase-3 readout
gate
5
positive readout
platform validated -
beyond COVID; launch
path to Moderna profit
readout failure
breaks the platform thesis
for the mRNA cancer franchise