Company: ERAS
Filing Date: 2025-03-20
Form Type: 10-K
Source: 0000950170-25-042682
Chunk: 17

Company: Erasca, Inc.
Filing Date: 2025-03-20
Form: 10-K
Item: Item 1
Chunk 17
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 ERK inhibitors in development are ATP-competitive and as a result, their potency is robust against the activated state of ERK. Based on this property, ERK inhibitors potentially can overcome drug resistance mechanisms that involve reactivation of RAS/MAPK pathway signaling, such as a rebound of RAS/MAPK signaling resulting from the alleviation of negative feedback or an upstream RAS/MAPK pathway protein adopting an acquired resistance mutation.

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Our therapeutic strategies for shutting down the RAS/MAPK pathway

We believe that to effectively shut down a pathway that signals as promiscuously as RAS/MAPK, a holistic approach must be taken to target not just single nodes, but multiple nodes and cooperative mechanisms in parallel. Our internally and externally sourced RAS/MAPK pathway-focused pipeline, comprising several targeted therapy programs, is one of the deepest in the industry. The target breadth and molecular diversity represented in our pipeline enable us to pursue a systematic, data-driven, portfolio-wide clinical development effort to identify single agent and combination approaches that aim to prolong survival in numerous patient populations with high unmet medical needs. We are pursuing three therapeutic strategies that may be used in combination with the goal of comprehensively, and perhaps synergistically, shutting down the RAS/MAPK pathway:

1.Target upstream and downstream MAPK pathway nodes with single agents and combinations intended to clamp these oncogenic drivers. Our lead product candidate, naporafenib, targets RAF, a key node of the RAS/MAPK pathway. We are developing naporafenib in combination with the MEK inhibitor trametinib and other targeted therapies to delay emergence of resistance in response to RAS/MAPK pathway inhibition. We are also evaluating drug combinations targeting upstream and downstream nodes to shut down, or "clamp," the signaling of various oncogenic drivers such as RTKs, NF1, RAS, RAF, and MEK alterations, trapped between the inhibited nodes. With our MAPKlamp approach, we hope to induce tumor regression in RAS/MAPK pathway-driven cancers, while also blocking the in-pathway escape routes that lead to tumor resistance.

2.Target RAS, the midstream MAPK pathway node, directly with single agents and combinations. Our RAS-targeting franchise, ERAS-0015 and ERAS-4001, consists of molecules that are designed to potently and selectively bind to oncogenic RAS alterations (e.g., G12X, G13X +/- Q61X) and to block activation of wild