Erasca Announces Promising Early Clinical Data for ERAS-0015 and 2026-2027 Milestones
Rhea-AI Summary
Erasca (NASDAQ: ERAS) reported early Phase 1 clinical progress for its RAS franchise. ERAS-0015 showed ongoing responses including two confirmed partial responses and one unconfirmed partial response observed at 8 mg QD, with favorable safety (no dose-limiting toxicities) and linear pharmacokinetics; data cutoff was January 7, 2026. INDs for ERAS-0015 and ERAS-4001 were cleared in May 2025. Initial Phase 1 monotherapy topline data for ERAS-0015 are planned for H1 2026, with expansion and combination cohorts in H2 2026 and additional data in 2027. ERAS-4001 monotherapy topline data are planned for H2 2026 with cohorts in 2027.
Positive
- Two confirmed partial responses and one unconfirmed PR observed at 8 mg QD
- No dose-limiting toxicities reported across evaluated dose levels
- Linear pharmacokinetics observed across all dose levels evaluated
- ERAS-0015 enrolling ahead of plan; dose escalation advancing faster than anticipated
- INDs for ERAS-0015 and ERAS-4001 cleared in May 2025
Negative
- Topline Phase 1 monotherapy data for ERAS-0015 not expected until H1 2026
- Initial ERAS-4001 monotherapy topline data not expected until H2 2026
- Clinical readouts reflect early, dose-escalation results with limited patient numbers as of Jan 7, 2026
News Market Reaction
On the day this news was published, ERAS declined 7.84%, reflecting a notable negative market reaction. Argus tracked a peak move of +17.9% during that session. Argus tracked a trough of -7.6% from its starting point during tracking. Our momentum scanner triggered 62 alerts that day, indicating high trading interest and price volatility. This price movement removed approximately $182M from the company's valuation, bringing the market cap to $2.14B at that time.
Data tracked by StockTitan Argus on the day of publication.
Key Figures
Market Reality Check
Peers on Argus
ERAS gained 16.35%, while peers were mixed: ALMS up 5.73%, OLMA up 7.96%, ITOS flat-to-slightly positive, PRTA flat, and ZVRA down 2.41%. No peers appeared in the momentum scanner, pointing to a stock-specific reaction to ERAS clinical data.
Historical Context
| Date | Event | Sentiment | Move | Catalyst |
|---|---|---|---|---|
| Jan 06 | Conference appearance | Neutral | +4.0% | J.P. Morgan Healthcare Conference presentation and investor meetings announcement. |
| Nov 25 | Conference appearance | Neutral | +6.2% | Evercore Healthcare Conference participation and webcast details. |
| Nov 12 | Earnings update | Neutral | +12.3% | Q3 2025 financials, cash runway to H2 2028, and 2026 data timing. |
| Nov 06 | Patent issued | Positive | +1.8% | U.S. patent issuance covering ERAS-0015 composition of matter to 2043. |
| Nov 04 | Conference schedule | Neutral | -2.9% | Multiple November healthcare conference presentations and webcasts. |
Recent news, including patent and R&D updates, often coincided with positive price reactions, suggesting sensitivity to pipeline and financing milestones.
Over the past several months, Erasca highlighted its RAS-focused strategy through conference participation and IP wins. On Nov 12, 2025, it reported Q3 2025 results, noting $362.4M in cash and marketable securities and funding into H2 2028, alongside expectations for initial 2026 data from ERAS-0015 and ERAS-4001. A September 2043 patent for ERAS-0015 further reinforced the franchise. Today’s early Phase 1 responses and detailed 2026–2027 milestones build directly on those prior preclinical and strategic disclosures.
Regulatory & Risk Context
An effective S-3 shelf filed on Aug 12, 2025 allows Erasca to issue up to $500,000,000 in securities, including up to $200,000,000 of common stock via an at-the-market program, providing flexible financing capacity alongside its clinical development plans.
Market Pulse Summary
The stock moved -7.8% in the session following this news. A negative reaction despite encouraging early responses would fit a scenario where investors reassessed risk in light of long development timelines and existing financing capacity. Previous RAS-franchise news with an average 2.1% move suggested more muted reactions. Any sharp downside could reflect concerns about future capital needs under the $500,000,000 shelf or uncertainty around translating early Phase 1 signals into later-stage outcomes.
Key Terms
pharmacokinetics medical
PK medical
partial responses medical
Phase 1 medical
monotherapy medical
KRAS medical
RAS/MAPK pathway medical
pan-KRAS inhibitor medical
AI-generated analysis. Not financial advice.
Encouraging early clinical activity, including confirmed partial responses in multiple tumor types with different RAS mutations, coupled with promising safety and pharmacokinetics data, observed for ERAS-0015 during dose escalation
Initial Phase 1 monotherapy data for ERAS-0015 (potential best-in-class pan-RAS molecular glue) planned for H1 2026 and for ERAS-4001 (potential first-in-class pan-KRAS inhibitor) planned for H2 2026
SAN DIEGO, Jan. 12, 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 meaningful clinical progress for its RAS-targeting franchise and 2026-2027 milestones.
“With both ERAS-0015 and ERAS-4001 INDs previously cleared in May 2025, Erasca’s strong operational execution continues to result in rapid clinical advancement of our RAS-targeting franchise. Notably, ERAS-0015 is now enrolling ahead of plan, thus providing early clinical data,” said Jonathan E. Lim, M.D., Erasca’s chairman, CEO, and co-founder. “During dose escalation, ERAS-0015 has already demonstrated promising early clinical activity with multiple ongoing confirmed and unconfirmed responses achieved, along with encouraging safety and tolerability data and well-behaved PK. We believe that observing first clinical responses in multiple patients at just 1/10th of the dose at which first clinical responses were observed with RMC-6236 is thesis-reinforcing in terms of ERAS-0015’s potential differentiation.”
Pipeline Progress and 2026-2027 Milestones
ERAS-0015 – Potential best-in-class RAS-targeting molecule
- Dose escalation in ongoing AURORAS-1 Phase 1 trial advancing faster than anticipated due to significant unmet medical need and high investigator and patient enthusiasm
- Ongoing confirmed and unconfirmed responses observed in multiple patients with differing tumor types and RAS mutations
- Ongoing responses (two confirmed partial responses (PRs) and one unconfirmed PR) observed in patients with different tumor types and RAS mutations achieved at a low dose of 8 mg QD
- Additional ongoing unconfirmed responses observed in patients at doses above 8 mg QD
- Favorable safety and tolerability, with no dose-limiting toxicities and predominantly low-grade adverse events observed at all dose levels evaluated to date*
- Well-behaved, linear pharmacokinetics (PK) across all dose levels evaluated to date with no evidence of exposure plateau*
- Milestones
- Initial Phase 1 monotherapy data in patients with RAS-mutant solid tumors planned for the first half of 2026**
- Initiation of monotherapy expansion cohorts and combination dose escalation cohorts planned for the second half of 2026
Monotherapy expansion data and combination dose escalation data planned for 2027**
* Data cutoff date was January 7, 2026
** Topline safety, tolerability, PK, and initial efficacy data
ERAS-4001 – Potential first-in-class pan-KRAS inhibitor
- Dose escalation in ongoing BOREALIS-1 Phase 1 trial continues to advance as expected
- Milestones
- Initial Phase 1 monotherapy data in patients with KRAS-mutant solid tumors planned for the second half of 2026**
- Initiation of monotherapy expansion cohorts and combination dose escalation cohorts planned for 2027
** Topline safety, tolerability, PK, and initial efficacy data
About ERAS-0015
ERAS-0015 is an 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, well-behaved, linear PK, and confirmed and unconfirmed responses in multiple patients across multiple tumor types with different RAS mutations, including confirmed and unconfirmed partial responses at doses as low as 8 mg once daily (QD). In preclinical studies versus RMC-6236, ERAS-0015 demonstrated approximately 8-21 times higher binding affinity to cyclophilin A (CypA) , approximately 5 times greater potency in RAS inhibition, and greater in vivo antitumor activity evidenced by achieving comparable or greater tumor growth inhibition or regression at doses that are as low as approximately one-tenth to one-fifth of the dose of RMC-6236. 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 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 ERAS-4001, and the planned advancement of our development pipeline, including the anticipated timing of data readouts for the AURORAS-1 and BOREALIS-1 trials. 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: 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; observations regarding the first dosage level at which a clinical response is detected are based on data generated within individual clinical trials, and comparisons of such clinical observations across different trials involve data from separate trials with distinct designs, patient populations, and methodologies, and therefore may not be directly comparable; any forward-looking statements regarding dose-response relationships reflect current expectations and/or assumptions are subject to risks and uncertainties that could cause actual results to differ materially; our assumptions about the development potential of ERAS-0015 and ERAS-4001 are based in large part on the preclinical data generated by the licensors and we may observe materially and adversely different results as we conduct our planned studies and trials; 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 or early clinical trials 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; unfavorable results from preclinical studies or clinical trials; we may be unable to secure partnerships or other strategic collaborations for naporafenib on acceptable terms or at all; 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; 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, 2024, 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
FAQ
What early clinical activity did ERAS report for ERAS-0015 (ERAS) on January 12, 2026?
When will Erasca (ERAS) release initial Phase 1 monotherapy data for ERAS-0015?
What are the next clinical milestones for ERAS-4001 (ERAS)?
Did Erasca report any safety concerns for ERAS-0015 in the January 12, 2026 release?
What regulatory progress did Erasca (ERAS) note for its RAS-targeting programs?
