Competitor RAS drug approval and premium pricing provide incremental upside for Erasca, while ERAS-0015's core path remains unchanged

Overview

The report analyzes what the approval of Revolution Medicines' pan-RAS inhibitor Rasonque means for the development, pricing, and valuation of Erasca's two RAS-pathway programs. Goldman Sachs concludes that the event is incrementally positive for ERAS, primarily because commercial pricing exceeded prior expectations, while ERAS-0015's development path and the central debate surrounding its clinical competitiveness remain unchanged.

Core views

Competitor Rasonque (daraxonrasib) received US FDA approval for adults with metastatic pancreatic ductal adenocarcinoma who have received at least one prior systemic therapy or are not suitable for multi-agent systemic therapy. The label specifies an oral dose of 300mg once daily; in the event of adverse reactions, the dose may first be reduced to 200mg and then to 150mg, with permanent discontinuation if 150mg remains intolerable. The label has no boxed warning. Its principal warnings and precautions include skin toxicity, stomatitis, diarrhea, gastrointestinal perforation, and interstitial lung disease or pneumonitis. For skin reactions, the label recommends daily prophylactic use of topical corticosteroids on the face and chest and suggests considering prophylactic oral antibiotics before treatment. Goldman Sachs believes these safety provisions are broadly consistent with prior expectations. The eligible population is broader than for some targeted therapies: the label does not require confirmation of a RAS mutation or a companion diagnostic. Goldman Sachs believes the broad label does not preclude other pan-RAS drugs from advancing into first-line treatment. The competitor has already initiated trials of daraxonrasib as first-line monotherapy and in combination with chemotherapy, while Erasca expects to initiate a pivotal trial of ERAS-0015 in first-line pancreatic ductal adenocarcinoma in 2027. Therefore, this approval does not change Goldman Sachs' view of ERAS-0015's potential development path, nor does it resolve the core debate over the program's clinical differentiation and competitiveness. ERAS-0015 also received Fast Track designation for metastatic pancreatic ductal adenocarcinoma during the week the report was published. The more evident positive impact from this event comes from pricing. Rasonque uses uniform pricing across different strengths, with both the 100mg and 150mg formulations, supplied as 30 tablets per bottle, carrying a monthly list price of US$39,800. By comparison, approved KRAS G12C inhibitors have monthly list prices of approximately US$23,000. Rasonque's initial gross-to-net discount is expected to be 20%-30%, mainly due to the high proportion of Medicare Part D patients and statutory rebates, while patients' annual out-of-pocket costs are capped at US$2,100. Based on this, Goldman Sachs updated ERAS-0015's modeled list price to approximately US$40,000/month but maintained its 25% gross-to-net discount assumption. The pricing adjustment increased the unadjusted peak sales forecast for ERAS-0015 from approximately US$9 billion to approximately US$16 billion. Goldman Sachs also modestly increased its 2030-2034 operating expense forecasts to reflect commercial expansion; in the model, 2034 operating expenses are linked to sales. The report's diluted GAAP earnings-per-share forecasts are: US$-0.86 in 2026, US$-0.34 in 2027, US$-0.64 in 2028, US$-0.73 in 2030, and US$5.57 in 2035. These forecasts indicate that the model continues to expect the company to incur losses before commercial sales ramp up, with long-term profitability dependent on product revenue reaching scale. Clinical data remain the decisive factor. Goldman Sachs views the ERAS-0015 update in 1H27 as the most important event for the stock. The update is expected to include monotherapy expansion-dose data at 24mg and 32mg, as well as combination therapy data, including data from the combination with panitumumab in colorectal cancer. The report will also continue to monitor the competitive landscape, including updates on RAS programs at the ESMO meeting from October 23 to 27. GenFleet is expected to present pan-RAS data, and titles for late-breaking abstracts are expected to be released on September 25. Regarding nearer-term product milestones, Erasca expects to report preliminary Phase I data for the pan-KRAS inhibitor ERAS-4001 in 2H26, involving approximately several dozen patients and covering safety, pharmacokinetics, pharmacodynamics, and preliminary efficacy. Goldman Sachs is focused on two questions: whether preserving HRAS/NRAS activity can give ERAS-4001 better tolerability than pan-RAS approaches, and whether its early response results can at least match those of pan-RAS inhibitors while providing a meaningful comparison with mutation-selective approaches. Valuation is highly sensitive to the probability of clinical success and long-term discounting assumptions. The report tests a bear-case WACC of 21% and terminal growth rate of -2%, as well as a bull-case WACC of 8% and terminal growth rate of 5%. At the base-case 40% probability of success in first-line pancreatic cancer, the valuation outcomes under the two scenarios are US$11 and US$48, respectively; as the probability of success rises from 0% to 100%, the valuation ranges increase from US$6 to US$17 and from US$26 to US$80, respectively. For second-line non-small cell lung cancer, the base probability of success is 50%, corresponding to US$11 and US$48; as the probability of success rises from 0% to 100%, the two scenarios increase from US$8 to US$13 and from US$38 to US$58, respectively. For colorectal cancer, the base probability of success is 30%, corresponding to US$11 and US$48; as the probability of success rises from 0% to 100%, the two scenarios increase from US$8 to US$17 and from US$37 to US$74, respectively. This indicates that higher pricing expands the commercial opportunity, but ultimate value still primarily depends on clinical validation, the cost of capital, and terminal growth assumptions. Goldman Sachs classifies ERAS as Early-Stage Biotech. Under the policy stated in the report, such companies have no drugs, therapies, or medical devices that have completed Phase II clinical trials and no distribution licenses for post-Phase II products; therefore, no investment rating or price target is assigned.

Analysis framework

Goldman Sachs first compares Rasonque's approved indication, safety provisions, and dosing management with prior expectations, then assesses their implications for the first-line development path and competitive landscape of pan-RAS drugs. It subsequently uses the approved product's price and KRAS G12C drugs as benchmarks to update ERAS-0015's pricing, peak sales, and operating expense models. Finally, it tests valuation sensitivity under different probabilities of clinical success, WACC, and terminal growth rate scenarios and chronologically maps subsequent data milestones for ERAS-4001, competitors, and ERAS-0015.

Methodology notes

• Event Games and Behavioral FinanceEvent-driven analysis

  Competitor approval event mapping

  The report maps Rasonque's approved indication, safety, and pricing terms to ERAS-0015's development feasibility, commercial pricing, and competitive path to assess the event's incremental impact on Erasca.

• Valuation MethodologyDCF Discounted Cash Flow

  WACC and terminal growth rate sensitivity analysis

  The report uses a bear-case assumption of 21% WACC and a -2% terminal growth rate, and a bull-case assumption of 8% WACC and a 5% terminal growth rate, to demonstrate the valuation impact of changes in the cost of capital and long-term growth assumptions.

• (Method outside the vocabulary)

  Clinical probability of success (PoS) scenario analysis

  The report separately varies ERAS-0015's probability of success in first-line pancreatic cancer, second-line non-small cell lung cancer, and colorectal cancer while holding assumptions for other programs unchanged, thereby quantifying the valuation impact of an individual clinical outcome.

Asset mapping & comparison

Structured mapping from thesis to named assets (strengths, weaknesses, peers, risks).

• Erasca Inc. (ERAS.US)

  The approval and premium pricing of a competitor's pan-RAS drug provide an incrementally positive readthrough for the development and commercialization assumptions of Erasca's ERAS-0015.

  Strengths

  ERAS-0015 received Fast Track designation for metastatic pancreatic ductal adenocarcinoma; Rasonque's pricing supports Goldman Sachs raising its modeled list price to approximately US$40,000/month and increasing its unadjusted peak sales forecast to approximately US$16 billion.

  Weaknesses

  Key ERAS-0015 monotherapy expansion and combination therapy data are not expected until 1H27, while ERAS-4001 is only expected to provide early Phase I data in 2H26.

  Comparison

  ERAS-0015 must compete with pan-RAS approaches such as Rasonque; ERAS-4001's tolerability and early response results will be compared with pan-RAS and mutation-selective approaches.

  Risks

  Changes in the probability of clinical success and in WACC and terminal growth rate assumptions could significantly affect valuation, while subsequent RAS data from competitors could also alter the competitive assessment.

Key data

• Rasonque approved indicationMetastatic pancreatic ductal adenocarcinomaFor adult patients who have received at least one prior systemic therapy or are not suitable for multi-agent systemic therapy; no confirmation of a RAS mutation or companion diagnostic is required
• Rasonque recommended dose300mg once dailyFor adverse-reaction management, reduce sequentially to 200mg and 150mg; permanently discontinue if 150mg remains intolerable
• Rasonque monthly list priceUS$39,800/monthUniform pricing for 100mg and 150mg formulations, with 30 tablets per bottle
• KRAS G12C inhibitor pricing benchmarkApproximately US$23,000/monthRasonque commands a clear pricing premium over recently approved targeted oncology drugs
• Rasonque initial gross-to-net discount20%-30%Primarily influenced by the Medicare Part D patient mix and statutory rebates
• Annual patient out-of-pocket cost capUS$2,100Applicable in the Medicare Part D context described in the report
• ERAS-0015 modeled priceApproximately US$40,000/monthUpdated based on Rasonque's pricing
• ERAS-0015 gross-to-net discount assumption25%Unchanged in this model update
• ERAS-0015 unadjusted peak sales forecastApproximately US$16 billionPrevious forecast was approximately US$9 billion
• Diluted GAAP earnings-per-share forecast2026 US$-0.86; 2027 US$-0.34; 2028 US$-0.64; 2030 US$-0.73; 2035 US$5.57Forecasts presented in the model update table
• ERAS-0015 key data timing1H27Includes 24mg and 32mg monotherapy expansion doses and data including panitumumab combination therapy in colorectal cancer
• ERAS-4001 preliminary Phase I data timing2H26Expected to cover safety, PK/PD, and preliminary efficacy in approximately several dozen patients
• Valuation scenario parametersBear case: WACC 21%, TGR -2%; bull case: WACC 8%, TGR 5%Used to test valuation sensitivity to changes in the probability of clinical success
• Historical price targets and closing prices2025-03-21: US$3.00/US$1.53; 2024-10-25: US$3.50/US$2.64; 2024-08-13: US$3.00/US$2.60; 2024-05-20: US$4.00/US$2.24; 2024-04-01: US$7.00/US$2.16Historical price target/closing price, respectively; prices in the table are not adjusted for corporate actions and do not indicate that this report has a current price target

Impact & implications

Goldman Sachs believes Rasonque's broad label and approximately US$40,000 monthly price validate the substantial commercial opportunity for pan-RAS drugs, providing upside support for ERAS-0015's pricing and peak sales assumptions. However, the competitor's approval itself does not change ERAS-0015's clinical development path or resolve the differentiation debate. Erasca's ultimate value still depends on safety, efficacy, and combination therapy data from 2H26 through 1H27, as well as the probability of clinical success in each indication.

Risks

• ERAS-0015's valuation is highly sensitive to the probability of clinical success in first-line pancreatic cancer, second-line non-small cell lung cancer, and colorectal cancer.
• Valuation is highly sensitive to WACC and terminal growth rate assumptions, with the report using markedly different parameters in its bear- and bull-case scenarios.
• Whether ERAS-4001 can improve tolerability by preserving HRAS/NRAS activity and whether its early efficacy can reach the level of pan-RAS inhibitors remain subject to validation by preliminary clinical data.
• Pan-RAS data from competitors such as GenFleet could affect the relative competitive positioning of ERAS programs.

What to watch

• Monitor ERAS-0015's 24mg and 32mg monotherapy expansion data and combination therapy data in 1H27, including results from the combination with panitumumab in colorectal cancer.
• Monitor RAS program updates at the ESMO meeting from October 23 to 27, particularly GenFleet's pan-RAS data; titles for late-breaking abstracts are expected to be released on September 25.
• Monitor ERAS-4001 safety, PK/PD, and preliminary efficacy data from approximately several dozen patients in 2H26.
• Monitor whether preserving HRAS/NRAS activity enables ERAS-4001 to improve tolerability and whether its response results can at least match those of pan-RAS inhibitors.
• Monitor the pivotal first-line ERAS-0015 trial in pancreatic ductal adenocarcinoma that Erasca expects to initiate in 2027.