Erasca Announces Updated Preliminary Phase 1 Data and Registration-Enabling Plans for Potentially Best-in-Class Pan-RAS Molecular Glue ERAS-0015 in KRAS-Mutant Solid Tumors
Rhea-AI Summary
Erasca (Nasdaq: ERAS) reported updated preliminary Phase 1 AURORAS-1 data for pan-RAS molecular glue ERAS-0015 in RAS-mutant solid tumors and outlined potentially registration-enabling plans in lung and pancreatic cancers.
At the recommended dose for expansion (RDE) of 32 mg QD, ERAS-0015 monotherapy showed a 57% uORR at 8 weeks (N=7) in second-line or later KRAS G12X pancreatic ductal adenocarcinoma, with most enrolled patients remaining on treatment across 24 mg and 32 mg doses and a median relative dose intensity of 100% at both doses. Safety remained generally consistent with prior disclosures, with mostly low-grade treatment-related adverse events, no dose-limiting toxicities, low rates of dose interruptions or reductions due to TRAEs, and no discontinuations due to TRAEs.
In metastatic colorectal cancer, the first dose-escalation cohort combining ERAS-0015 16 mg with the approved commercial dose of panitumumab reported no DLTs in four DLT-evaluable patients, enabling cohort clearance and ongoing backfill and dose escalation. According to Erasca, additional monotherapy and combination data are expected in the first half of 2027. The company plans to initiate a potentially registration-enabling trial in 2L+ NSCLC in H1 2027, a Phase 3 pivotal trial in first-line pancreatic cancer in 2027, and a Phase 3 pivotal trial in RAS-mutant NSCLC between H2 2027 and H1 2028.
AI-generated analysis. How Rhea-AI works. Not financial advice.
Positive
- 57% uORR at 8 weeks (N=7) in 2L+ KRAS G12X PDAC at 32 mg QD RDE
- 100% median relative dose intensity at both 24 mg QD and 32 mg QD
- No DLTs and mostly low-grade TRAEs; no TRAE-related discontinuations in monotherapy
- No DLTs in first ERAS-0015 16 mg + panitumumab combination cohort (4 DLT-evaluable patients)
- Backfill and dose escalation ongoing in 16 mg and 24 mg panitumumab combination cohorts
- Company targets multiple potentially registration-enabling and Phase 3 trials in NSCLC and PDAC starting 2027
Negative
- None.
Key Figures
Previous Clinical trial Reports
| Date | Event | Sentiment | 24h Move | Catalyst |
|---|---|---|---|---|
| May 11 | Merck trial collaboration | Positive | +3.2% | Clinical trial collaboration with Merck to combine ERAS-0015 with KEYTRUDA. |
| Apr 27 | Phase 1 dose data | Positive | -48.3% | Positive preliminary Phase 1 dose escalation data for ERAS-0015 in solid tumors. |
| Jan 12 | Early Phase 1 update | Positive | -7.8% | Promising early ERAS-0015 responses and 2026–2027 clinical milestones outlined. |
| Jun 02 | IND clearance | Positive | +1.8% | FDA IND clearance for ERAS-4001 and ERAS-0015 targeting KRAS-mutant tumors. |
| Apr 29 | Preclinical data | Positive | +2.1% | New preclinical RAS-franchise data presented at AACR highlighting ERAS-0015 and ERAS-4001. |
24h Move is the share-price change in the day after each event; other market factors may also have contributed.
Clinical-trial headlines for ERAS have produced mixed reactions, with several positive ERAS-0015 updates met by sharp share-price declines.
Key Terms
qd medical
dlt medical
orr medical
AI-generated analysis. How Rhea-AI works. Not financial advice.
At RDE of 32 mg QD, encouraging monotherapy responses with
Monotherapy has been generally well-tolerated at RDEs
Promising combination potential, including no DLTs, encouraging safety data, and clearance of first dose escalation combination cohort of ERAS-0015 (16 mg) with approved commercial dose of panitumumab
Additional ERAS-0015 monotherapy and combination data expected H1 2027, including panitumumab combination data
Company plans to initiate a potentially registration-enabling trial in lung cancer in H1 2027, a Phase 3 trial in pancreatic cancer in 2027, and an additional Phase 3 trial in lung cancer in H2 2027 to H1 2028
SAN DIEGO, July 13, 2026 (GLOBE NEWSWIRE) -- Erasca, Inc. (Nasdaq: ERAS), a clinical-stage precision oncology company singularly focused on discovering, developing, and commercializing therapies for patients with RAS/MAPK pathway-driven cancers, today announced updated preliminary Phase 1 data for its potentially best-in-class, pan-RAS molecular glue ERAS-0015 in patients with RAS-mutant solid tumors. The Company also announced clinical development plans for the ERAS-0015 program, including potentially registration-enabling trials in lung and pancreatic cancers.
Updated preliminary data from Erasca's ongoing AURORAS-1 Phase 1 trial in the U.S. builds on the Company's April 2026 announcement, with additional patients and longer follow-up.
“We believe the continued notable responses in patients with pancreatic cancer in the U.S., together with the encouraging data in lung cancer and early signal in combination with panitumumab in metastatic colorectal cancer that we have seen in Phase 1, underscore the broad potential of ERAS-0015 to become a foundational therapy for multiple RAS-mutant solid tumors,” said Jonathan E. Lim, M.D., Erasca’s chairman, CEO, and co-founder. “We look forward to additional preliminary monotherapy and combination data expected in the first half of 2027. We believe that we are well positioned to execute our robust clinical development plan and transition into Phase 3 development.”
Encouraging Monotherapy Responses Observed in Second Line or Greater (2L+) KRAS G12X Pancreatic Ductal Adenocarcinoma (PDAC)1
57% uORR8wk (N=7) at recommended dose for expansion (RDE) of 32 mg QD2- Across doses, all patients with either confirmed or unconfirmed responses remained on treatment
- At RDE of 32 mg QD, 6 of 7 enrolled patients remained on treatment; at RDE of 24 mg QD, 6 of 8 enrolled patients remained on treatment
With Additional Patients and Longer Follow-up, Monotherapy Safety Data Remained Consistent with Prior Disclosure and ERAS-0015 Continued to be Generally Well-Tolerated1
- Frequency and severity of treatment-related adverse events (TRAEs) remained consistent with the Company’s April 2026 announcement
- Mostly low-grade TRAEs, no dose-limiting toxicities (DLTs), low rate of dose interruptions or reductions due to TRAEs, and no discontinuations due to TRAEs
- Median relative dose intensity (RDI) was
100% at both 24 mg QD and 32 mg QD
Promising Combination Potential with Panitumumab in Metastatic Colorectal Cancer (CRC), including Clearance of First Dose Escalation Cohort3
- No DLTs were observed for the combination in the 16 mg cohort during dose escalation in four DLT-evaluable patients
- Backfill enrollment is ongoing in the 16 mg combination cohort
- Dose escalation is ongoing with continued enrollment in the 24 mg combination cohort
Accelerating Potentially Registration-Enabling Development Plans in Highest Value Indications
- Initiate potentially registration-enabling trial in 2L+ NSCLC in 1H27
- Initiate 1L PDAC Phase 3 pivotal trial in 2027
- Initiate RASm NSCLC Phase 3 pivotal trial in 2H27-1H28
____________________
1 Data cutoff (DCO) May 25, 2026
2 The uORR8wk is the overall response rate (ORR) (confirmed and unconfirmed responses) for patients who received first dose of ERAS-0015 at least 8 weeks prior to the May 25, 2026 cutoff date
3 DCO July 6, 2026
About ERAS-0015
ERAS-0015 is an investigational, oral, highly potent pan-RAS molecular glue designed to inhibit RAS signaling with a potential best-in-class profile. Erasca is evaluating ERAS-0015 in the AURORAS-1 Phase 1 trial in patients with RAS-mutant solid tumors. Early dose escalation data in AURORAS-1 demonstrated favorable safety and tolerability results, well-behaved, linear PK, and confirmed and unconfirmed partial responses in multiple patients across multiple tumor types with different RAS mutations, including confirmed partial responses at doses as low as 8 mg once daily (QD). ERAS-0015 is also designed to prevent resistance against mutant-selective inhibitors through inhibition of RAS wildtype variants. In addition, ERAS-0015 has demonstrated favorable absorption, distribution, metabolism, and excretion (ADME) and pharmacokinetic (PK) properties in multiple animal species.
About ERAS-4001
ERAS-4001 is an investigational, oral, highly potent, and selective pan-KRAS inhibitor with a potential first-in-class and best-in-class profile. Erasca is evaluating ERAS-4001 in the BOREALIS-1 Phase 1 trial in patients with KRAS-mutant solid tumors. ERAS-4001 demonstrated favorable preclinical in vitro potency against KRAS G12X mutations as well as KRAS wildtype amplifications, which may limit treatment resistance mediated through KRAS wildtype activation. No activity was observed for ERAS-4001 against HRAS or NRAS wildtype proteins in preclinical studies, which may enable a better therapeutic window compared to pan-RAS inhibitors. ERAS-4001 showed potent activity against both GTP-bound (active state) and GDP-bound (inactive state) KRAS with single digit nanomolar IC50s. In vivo, ERAS-4001 induced tumor regression in multiple KRAS-mutant models. In preclinical studies, ERAS-4001 showed encouraging ADME and PK properties.
About Erasca
At Erasca, our name is our mission: To erase cancer. We are a clinical-stage precision oncology company singularly focused on discovering, developing, and commercializing therapies for patients with RAS/MAPK pathway-driven cancers. Our company was co-founded by leading pioneers in precision oncology and RAS targeting to create novel therapies and combination regimens designed to comprehensively shut down the RAS/MAPK pathway for the treatment of patients with cancer. We believe our team’s capabilities and experience, further guided by our scientific advisory board which includes the world’s leading experts in the RAS/MAPK pathway, uniquely position us to achieve our bold mission of erasing cancer.
Cautionary Note Regarding Forward-Looking Statements
Erasca cautions you that statements contained in this press release regarding matters that are not historical facts are forward-looking statements. The forward-looking statements are based on our current beliefs and expectations and include, but are not limited to: our expectations regarding the potential therapeutic benefits of our product candidates, including ERAS-0015, and the planned advancement of our development pipeline, including the anticipated timing of data readouts for the AURORAS-1 trial, and the initiation of the clinical trials of ERAS-0015 described in this press release, our expectations that our planned clinical trials will serve as registrational-enabling studies, characterizations of the clinical profile of ERAS-0015, the broad potential of ERAS-0015 to become a foundational therapy for multiple RAS-mutant solid tumors, the potential for ERAS-0015 to be used in combination therapies, the potential for ERAS-0015 to be best-in-class. Actual results may differ from those set forth in this press release due to the risks and uncertainties inherent in our business, including, without limitation: the timing of our clinical data readouts, including for the AURORAS-1 trial may be delayed; our product candidates, including ERAS-0015, may not demonstrate therapeutic benefits that we expect; interim, topline and preliminary results of a clinical trial are not necessarily indicative of final results and one or more of the clinical outcomes may materially change as patient enrollment continues, following more comprehensive reviews of the data and as more patient data becomes available, including the risk that an unconfirmed partial response to treatment may not ultimately result in a confirmed partial response to treatment after follow-up evaluations; our approach to the discovery and development of product candidates based on our singular focus on shutting down the RAS/MAPK pathway, a novel and unproven approach; results from preclinical studies not necessarily being predictive of future results; our assumptions around which programs may have a higher probability of success may not be accurate, and we may expend our limited resources to pursue a particular product candidate and/or indication and fail to capitalize on product candidates or indications with greater development or commercial potential; potential delays in the commencement, enrollment, data readout, and completion of clinical trials and preclinical studies; our dependence on third parties in connection with manufacturing, research, and preclinical and clinical testing; unexpected adverse side effects or inadequate efficacy of our product candidates that may limit their development, regulatory approval, and/or commercialization, or may result in recalls or product liability claims; our planned potentially registration-enabling trials may be delayed based on Food and Drug Administration (FDA) feedback or requirements, as the FDA retains broad discretion to require additional clinical data prior to the conduct of a registrational trial or submission for regulatory approval; even if our planned trials are successful, they may not support regulatory approval; unfavorable results from preclinical studies or clinical trials; the inability to realize any benefits from our current licenses, acquisitions, and collaborations, and any future licenses, acquisitions, or collaborations, and our ability to fulfill our obligations under such arrangements; regulatory developments in the United States and foreign countries; our ability to obtain and maintain intellectual property protection for our product candidates and maintain our rights under intellectual property licenses, including our ability to successfully defend against allegations raised by, or any litigation initiated by, Revolution Medicines (RevMed) that ERAS-0015 infringes patents held by RevMed or was derived from RevMed trade secrets; the sufficiency of our cash, cash equivalents, and marketable securities to fund operations; we may use our capital resources sooner than we expect; and other risks described in our prior filings with the Securities and Exchange Commission (SEC), including under the heading “Risk Factors” in our annual report on Form 10-K for the year ended December 31, 2025, and any subsequent filings with the SEC. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof, and we undertake no obligation to update such statements to reflect events that occur or circumstances that exist after the date hereof. All forward-looking statements are qualified in their entirety by this cautionary statement, which is made under the safe harbor provisions of the Private Securities Litigation Reform Act of 1995.
Contact:
Joyce Allaire
LifeSci Advisors, LLC
jallaire@lifesciadvisors.com
Source: Erasca, Inc.
