P3 MAPKeeper 301 in 1L PDAC Underway

Research evidence excerpt

P3 MAPKeeper 301 in 1L PDAC Underway

data from an expanded cohort of 55 1L PDAC patients treated

Price Performance - 1 Year

with atebimetinib + mGnP, where the combo demonstrated mOS of 17.3 months vs.

the 8.5 month historical benchmark for GnP in MPACT. We got a more complete look USD

at baseline characteristics, which included fewer patients with liver mets (51% vs 85% 109

in MPACT) but more with peritoneal mets (36% vs 4% in MPACT). Notably, 60% of 8

patients went on to receive 2L treatment, including 1 patient receiving a RAS inhibitor 7

in 2L, vs. 40% in MPACT. We think this last point may be related to the combination’s 6

tolerability/safety profile, which included limited Gr 3+ TRAEs (anemia at 16% and 5

neutropenia at 18%, both deemed chemo-related), no reported Gr 4 atebi-related or Gr 4

5 TRAEs. Additionally, 84% of participants maintained or gained weight at three months, 2

a meaningful metric in a disease where cachexia can drive functional decline. 1

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physicians who were impressed by the OS data, including one who called it an

“outstanding” result, especially in the context of the tolerability profile. There was

particular interest in the weight stability/cachexia signal, including whether it could

have contributed to OS, helped preserve performance status as patients initiated 2L

treatment, and whether it could enable combination with full-dose chemo (answer: not

in the P3, where atebi is being combined with modified GnP to preserve QoL). A key

question was the extent that patient selection may have contributed to the 17.3-mo mOS

(e.g., fewer liver mets vs. MPACT) and how to reconcile atebi’s more modest 36% ORR