Erasca, Inc.

Previous wording

ERAS-0015 is a potential best-in-class, next-generation pan-RAS molecular glue in clinical development for the treatment of patients with RAS-mutated solid tumors. In vitro, ERAS-0015 has shown approximately 8-21 times higher binding affinity to cyclophilin A versus the most advanced pan-RAS molecular glue in development. We believe this higher binding affinity results in approximately 5 times more potent RAS inhibition in cell-based assays versus the comparator. ERAS-0015 also has favorable absorption, distribution, metabolism, and excretion (ADME) and pharmacokinetics (PK) properties in multiple animal species. As a result of these favorable in vitro potency and ADME/PK attributes, ERAS-0015 has demonstrated comparable to greater in vivo antitumor activity at doses which are approximately one-tenth to one-eighth of the dose of the most advanced pan-RAS molecular glue. In combination with an anti-PD-1 antibody, ERAS-0015 was able to achieve complete disappearance of tumors in mice on day 31. The combination of ERAS-0015 plus the anti-EGFR antibody cetuximab induced significant tumor growth inhibition and demonstrated the potential combination benefit of blocking both oncogenic drivers. Our initial clinical trial for ERAS-0015 is called AURORAS-1. The investigational new drug application (IND) for AURORAS-1 was cleared by the US Food and Drug Administration (FDA) in May 2025. ERAS-0015 is also being evaluated in the JYP0015M101 clinical trial in China for adult patients with advanced solid tumors harboring specific RAS mutations. The JYP0015M101 clinical trial is sponsored by Joyo. We initiated monotherapy expansion cohorts and combination dose escalation cohorts, including a pembrolizumab combination cohort, as part of the AURORAS-1 trial in the second quarter of 2026 and the first quarter of 2026, respectively, ahead of our previous guidance. We anticipate the associated data readouts in the first half of 2027.

Current wording

ERAS-0015 is a potential best-in-class, next-generation pan-RAS molecular glue in clinical development for the treatment of patients with RAS-mutated solid tumors. In vitro, ERAS-0015 has shown approximately 8-21 times higher binding affinity to cyclophilin A versus the most advanced pan-RAS molecular glue in development. We believe this higher binding affinity results in approximately 5 times more potent RAS inhibition in cell-based assays versus the comparator. ERAS-0015 also has favorable absorption, distribution, metabolism, and excretion (ADME) and pharmacokinetics (PK) properties in multiple animal species. As a result of these favorable in vitro potency and ADME/PK attributes, ERAS-0015 has demonstrated comparable to greater in vivo antitumor activity at doses which are approximately one-tenth to one-eighth of the dose of the most advanced pan-RAS molecular glue. In combination with an anti-PD-1 antibody, ERAS-0015 was able to achieve complete disappearance of tumors in mice on day 31. The combination of ERAS-0015 plus the anti-EGFR antibody cetuximab induced significant tumor growth inhibition and demonstrated the potential combination benefit of blocking both oncogenic drivers. Our initial clinical trial for ERAS-0015 is called AURORAS-1. The investigational new drug application (IND) for AURORAS-1 was cleared by the US Food and Drug Administration (FDA) in May 2025. ERAS-0015 is also being evaluated in the JYP0015M101 clinical trial in China for adult patients with advanced solid tumors harboring specific RAS mutations. The JYP0015M101 clinical trial is sponsored by Joyo. We initiated monotherapy expansion cohorts and combination dose escalation cohorts, including a panitumumab combination cohort, as part of the AURORAS-1 trial in the second quarter of 2026 and the first quarter of 2026, respectively, ahead of our previous guidance. We anticipate the associated data readouts in the first half of 2027. In addition, we initiated a combination dose escalation cohort with pembrolizumab in the first quarter of 2026.

Previous wording

Our next program is ERAS-12, our investigational EGFR D2/D3 biparatopic antibody (bpAb). ERAS-12 is a potential best-in-class biologic, for which we have identified a lead candidate, that is designed to inhibit EGFR through multiple proposed mechanisms of action. In tumors where EGFR signaling is thought to be a primary driver of tumor growth, an antibody-based approach has been shown to be an effective way to target the receptor. However, all approved anti-EGFR antibodies target domain III (D3) only, which is the main site for ligand binding, and no approved antibodies target domain II (D2), which is responsible for dimerization of EGFR upon ligand binding. Binding of D2 prevents both EGFR homodimerization as well as heterodimerization. We believe the combined binding of D2 and D3 could result in differentiated and improved inhibition of downstream EGFR signaling. ERAS-12 also aims to exploit the innate immune system to induce tumor cell apoptosis. The Fragment crystallizable (Fc) region of IgG1 antibodies contain binding spots for both immune effector cells (e.g., NK cells) and the classical complement component C1q. By combining novel cell signal inhibition with enhancements to the Fc, we aim to create a potent multi-modal BIC anti-EGFR biologic which we believe could function as a targeted therapy with immunomodulatory activity.

Current wording

Our next program is ERAS-12, our investigational EGFR D2/D3 biparatopic antibody (bpAb). ERAS-12 is a potential best-in-class biologic, for which we have identified a lead candidate, that is designed to inhibit EGFR through multiple proposed mechanisms of action. In tumors where EGFR signaling is thought to be a primary driver of tumor growth, an antibody-based approach has been shown to be an effective way to target the receptor. However, all approved anti-EGFR antibodies target domain III (D3) only, which is the main site for ligand binding, and no approved antibodies target domain II (D2), which is responsible for dimerization of EGFR upon ligand binding. Binding of D2 prevents both EGFR homodimerization as well as heterodimerization. We believe the combined binding of D2 and D3 could result in differentiated and improved inhibition of downstream EGFR signaling. ERAS-12 also aims to exploit the innate immune system to induce tumor cell apoptosis. The Fragment crystallizable (Fc) region of IgG1 antibodies contain binding spots for both immune effector cells (e.g., NK cells) and the classical complement component C1q. By combining novel cell signal inhibition with enhancements to the Fc, we aim to create a potent multi-modal BIC anti-EGFR biologic which we believe could function as a targeted therapy with immunomodulatory activity. In order to focus our resources on our RAS programs, we have made a strategic decision that future development of this program would be best advanced through a strategic partnership. Accordingly, we are no longer committing internal resources to the development of this program, and we intend to seek a partner to continue its development.

Previous wording

In May 2025, in connection with our expectation that ERAS-0015 and ERAS-4001 would both become clinical stage programs, we conducted a broader pipeline review. Following this review, in order to prioritize organizational focus and resources to advance our differentiated RAS-targeting franchise, we decided to evaluate strategic alternatives for our naporafenib program, which we in-licensed from Novartis Pharma AG (Novartis). After evaluating the clinical progress of our RAS franchise, we made a decision to stop development of naporafenib. In March 2026, we sent a notice to Novartis to terminate our exclusive license agreement with Novartis (as amended, the Novartis Agreement) pursuant to which we acquired exclusive rights to develop naporafenib. The effective date of the termination of the Novartis Agreement is June 3, 2026. In connection with such termination, we and Novartis have agreed that we shall continue to ensure that the patients currently enrolled in the SEACRAFT-1 and SEACRAFT-2 trials will be permitted to continue to receive treatment for the foreseeable future.

Current wording

In May 2025, in connection with our expectation that ERAS-0015 and ERAS-4001 would both become clinical stage programs, we conducted a broader pipeline review. Following this review, in order to prioritize organizational focus and resources to advance our differentiated RAS-targeting franchise, we decided to evaluate strategic alternatives for our naporafenib program, which we in-licensed from Novartis Pharma AG (Novartis). After evaluating the clinical progress of our RAS franchise, we made a decision to stop development of naporafenib. In March 2026, we sent a notice to Novartis to terminate our exclusive license agreement with Novartis (as amended, the Novartis Agreement) pursuant to which we acquired exclusive rights to develop naporafenib. The effective date of the termination of the Novartis Agreement is June 3, 2026. In connection with such termination, we and Novartis have entered into a termination agreement, pursuant to which Novartis and we have agreed that we shall continue to ensure that the patients currently enrolled in the SEACRAFT-1 and SEACRAFT-2 trials will be permitted to continue to receive treatment for the foreseeable future.

Previous wording

In January 2026, we completed the sale and issuance of 25,875,000 shares of our common stock, including the exercise in full by the underwriters of their option to purchase 3,375,000 shares of our common stock, at a price to the public of $10.00 per share (the January 2026 Offering). Our aggregate net proceeds from the January 2026 Offering were $242.7 million, net of underwriting discounts and commissions of $15.5 million and offering costs of $0.5 million.

Current wording

In January 2026, we completed the sale and issuance of 25,875,000 shares of our common stock, including the exercise in full by the underwriters of their option to purchase 3,375,000 shares of our common stock, at a price to the public of $10.00 per share (the January 2026 Offering). Our aggregate net proceeds from the January 2026 Offering were $242.7 million, net of underwriting discounts and commissions and offering costs of $16.0 million.

Previous wording

Since our inception in 2018, we have devoted substantially all of our resources to organizing and staffing our company, business planning, raising capital, identifying, acquiring, and in-licensing our product candidates, establishing our intellectual property portfolio, conducting research, preclinical studies and clinical trials, establishing arrangements with third parties for the manufacture of our product candidates and related raw materials, and providing general and administrative support for these operations. We do not have any products approved for sale and have not generated any revenue. As of March 31, 2026, we have raised a total of $1.3 billion to fund our operations, comprised primarily of gross proceeds from our IPO, underwritten offerings, a private placement of our common stock, and the sale and issuance of convertible preferred stock. As of March 31, 2026, we had cash, cash equivalents, and marketable securities of $408.5 million.

Current wording

Since our inception in 2018, we have devoted substantially all of our resources to organizing and staffing our company, business planning, raising capital, identifying, acquiring, and in-licensing our product candidates, establishing our intellectual property portfolio, conducting research, preclinical studies and clinical trials, establishing arrangements with third parties for the manufacture of our product candidates and related raw materials, and providing general and administrative support for these operations. We do not have any products approved for sale and have not generated any revenue. As of June 30, 2026, we have raised a total of $1.3 billion to fund our operations, comprised primarily of gross proceeds from our IPO, underwritten offerings, a private placement of our common stock, and the sale and issuance of convertible preferred stock. As of June 30, 2026, we had cash, cash equivalents, and marketable securities of $384.3 million. In July 2026, we completed our July 2026 Offering with aggregate net proceeds of $593.5 million, net of underwriting discounts and commissions and estimated offering costs.

Previous wording

We have incurred significant operating losses since inception. Our net losses were $183.4 million and $31.0 million for the three months ended March 31, 2026 and 2025, respectively. As of March 31, 2026, we had an accumulated deficit of $1.1 billion. We expect our expenses and operating losses will increase substantially for the foreseeable future, particularly if and as we conduct our ongoing and planned clinical trials and preclinical studies; continue our research and development activities; utilize third parties to manufacture our product candidates and related raw materials; hire additional personnel; acquire, in-license, or develop additional product candidates; expand and protect our intellectual property; and incur additional costs associated with being a public company. If we obtain regulatory approval for any of our product candidates, we expect to incur significant commercialization expenses related to product sales, marketing, manufacturing, and distribution. In addition, as our product candidates progress through development and toward commercialization, we will need to make milestone payments to the licensors and other third parties from whom we have in-licensed our product candidates. Our net losses may fluctuate significantly from quarter-to-quarter and year-to-year, depending on the timing of our clinical trials and preclinical studies and our expenditures on other research and development activities.

Current wording

We have incurred significant operating losses since inception. Our net losses were $44.1 million and $33.9 million for the three months ended June 30, 2026 and 2025, respectively, and $227.5 million and $64.8 million for the six months ended June 30, 2026 and 2025, respectively. As of June 30, 2026, we had an accumulated deficit of $1.1 billion. We expect our expenses and operating losses will increase substantially for the foreseeable future, particularly if and as we conduct our ongoing and planned clinical trials and preclinical studies; continue our research and development activities; utilize third parties to manufacture our product candidates and related raw materials; hire additional personnel; acquire, in-license, or develop additional product candidates; expand and protect our intellectual property; and incur additional costs associated with being a public company. If we obtain regulatory approval for any of our product candidates, we expect to incur significant commercialization expenses related to product sales, marketing, manufacturing, and distribution. In addition, as our product candidates progress through development and toward commercialization, we will need to make milestone payments to the licensors and other third parties from whom we have in-licensed our product candidates. Our net losses may fluctuate significantly from quarter-to-quarter and year-to-year, depending on the timing of our clinical trials and preclinical studies and our expenditures on other research and development activities.

Previous wording

Based upon our current operating plans, we believe that our cash, cash equivalents, and marketable securities as of March 31, 2026 will be sufficient to fund our operations into the second half of 2028. We do not expect to generate any revenues from product sales until we successfully complete development and obtain regulatory approval for one or more of our product candidates, which we expect will take a number of years and may never occur. Accordingly, until such time as we can generate significant revenue from sales of our product candidates, if ever, we expect to finance our cash needs through equity offerings, debt financings, or other capital sources, including potential collaborations, licenses, and other similar arrangements. However, we may be unable to raise additional funds or enter into such other arrangements when needed on favorable terms or at all. Our failure to raise capital or enter into such other arrangements when needed would have a negative impact on our financial condition and could force us to delay, limit, reduce, or terminate our research and development programs or other operations, or grant rights to develop and market product candidates that we would otherwise prefer to develop and market ourselves.

Current wording

Based upon our current operating plans, we believe that our cash, cash equivalents, and marketable securities as of June 30, 2026, together with the net proceeds of $593.5 million received from the July 2026 Offering, will be sufficient to achieve the anticipated corporate milestones set forth in this quarterly report, including reporting data from the ongoing Phase 1 clinical trial of ERAS-0015; initiating potentially registration-enabling clinical trials of ERAS-0015 in 2L+ NSCLC, 1L PDAC and RASm NSCLC; reporting data from the ongoing Phase 1 clinical trial of ERAS-4001 as monotherapy; and initiating monotherapy expansion cohorts and combination dose escalation cohorts of ERAS-4001. We do not expect to generate any revenues from product sales until we successfully complete development and obtain regulatory approval for one or more of our product candidates, which we expect will take a number of years and may never occur. Accordingly, until such time as we can generate significant revenue from sales of our product candidates, if ever, we expect to finance our cash needs through equity offerings, debt financings, or other capital sources, including potential collaborations, licenses, and other similar arrangements. However, we may be unable to raise additional funds or enter into such other arrangements when needed on favorable terms or at all. Our failure to raise capital or enter into such other arrangements when needed would have a negative impact on our financial condition and could force us to delay, limit, reduce, or terminate our research and development programs or other operations, or grant rights to develop and market product candidates that we would otherwise prefer to develop and market ourselves.

Previous wording

Our financial condition and results of operations may also be impacted by other factors we may not be able to control, such as geopolitical and economic events. We do not believe that such factors had a material adverse impact on our results of operations during the three months ended March 31, 2026.

Current wording

Our financial condition and results of operations may also be impacted by other factors we may not be able to control, such as geopolitical and economic events. We do not believe that such factors had a material adverse impact on our results of operations during the three and six months ended June 30, 2026.

Previous wording

Research and development expenses were $27.3 million for the three months ended March 31, 2026 compared to $26.0 million for the three months ended March 31, 2025. The increase of $1.3 million was primarily driven by increases of $1.7 million in personnel costs, including stock-based compensation expense, and $1.0 million in expenses incurred in connection with clinical trials, preclinical studies, and discovery activities, partially offset by decreases of $1.1 million in outsourced services and consulting fees and $0.4 million in facilities-related expenses and depreciation.

Current wording

Research and development expenses were $35.9 million for the three months ended June 30, 2026 compared to $21.2 million for the three months ended June 30, 2025. The increase of $14.7 million was primarily driven by increases of $8.2 million in expenses incurred in connection with clinical trials, preclinical studies, and discovery activities, $3.7 million in outsourced services and consulting fees, and $2.8 million in personnel costs, including stock-based compensation expense.

Previous wording

In-process research and development expenses were $150.0 million for the three months ended March 31, 2026 compared to $0 for the three months ended March 31, 2025. In-process research and development expenses for the three months ended March 31, 2026 were related to our exercise of the option to expand our territory under the license agreement with Joyo.

Current wording

In-process research and development expenses were $0 for the three months ended June 30, 2026 compared to $7.5 million for the three months ended June 30, 2025. In-process research and development expenses for the three months ended June 30, 2025 were related to the achievement of milestones in connection with our license agreement with Joyo.

Previous wording

Other income (expense), net was $4.5 million for the three months ended March 31, 2026 compared to $4.7 million for the three months ended March 31, 2025. The decrease of $0.2 million was primarily related to a decrease in interest earned on our cash, cash equivalents, and marketable securities during the three months ended March 31, 2026.

Current wording

Other income (expense), net was $3.5 million for the three months ended June 30, 2026 compared to $4.2 million for the three months ended June 30, 2025. The decrease of $0.7 million was primarily related to a decrease in interest earned on our cash, cash equivalents, and marketable securities during the three months ended June 30, 2026.

Previous wording

In January 2026, we completed the sale and issuance of 25,875,000 shares of our common stock, including the exercise in full by the underwriters of their option to purchase 3,375,000 shares of our common stock, at a price to the public of $10.00 per share. Our aggregate net proceeds from the January 2026 Offering were $242.7 million, net of underwriting discounts and commissions of $15.5 million and offering costs of $0.5 million.

Current wording

In January 2026, we completed the sale and issuance of 25,875,000 shares of our common stock, including the exercise in full by the underwriters of their option to purchase 3,375,000 shares of our common stock, at a price to the public of $10.00 per share. Our aggregate net proceeds from the January 2026 Offering were $242.7 million, net of underwriting discounts and commissions and offering costs of $16.0 million.

Previous wording

As of March 31, 2026, we had cash, cash equivalents, and marketable securities of $408.5 million. Based upon our current operating plans, we believe that our cash, cash equivalents, and marketable securities will be sufficient to fund our operations into the second half of 2028. However, our forecast of the period of time through which our financial resources will be adequate to support our operations is a forward-looking statement that involves risks and uncertainties, and actual results could vary materially. We have based this estimate on assumptions that may prove to be wrong, and we could deplete our capital resources sooner than we expect. Additionally, the process of conducting preclinical studies and testing product candidates in clinical trials is costly, and the timing of progress and expenses in these studies and trials is uncertain.

Current wording

As of June 30, 2026, we had cash, cash equivalents, and marketable securities of $384.3 million. Based upon our current operating plans, we believe that our cash, cash equivalents, and marketable securities, together with the net proceeds of $593.5 million received from the July 2026 Offering, will be sufficient to fund our operations for at least the next twelve months. However, our forecast of the period of time through which our financial resources will be adequate to support our operations is a forward-looking statement that involves risks and uncertainties, and actual results could vary materially. We have based this estimate on assumptions that may prove to be wrong, and we could deplete our capital resources sooner than we expect. Additionally, the process of conducting preclinical studies and testing product candidates in clinical trials is costly, and the timing of progress and expenses in these studies and trials is uncertain.

Previous wording

Cash used in operating activities was $27.4 million during the three months ended March 31, 2026, primarily resulting from a net loss of $183.4 million, changes in operating assets and liabilities of $2.3 million, and accretion on marketable securities of $0.7 million, partially reduced by in-process research and development expenses of $150.0 million related to our exercise of the option to expand our territory under the license agreement with Joyo which are reflected in investing activities, stock-based compensation expense of $8.5 million, and depreciation and amortization expense of $0.7 million. Net cash used from changes in operating assets and liabilities consisted primarily of a decrease in accrued expenses and other current and long-term liabilities of $3.3 million, partially offset by an increase in accounts payable of $1.2 million.

Current wording

Cash used in operating activities was $54.7 million during the six months ended June 30, 2026, primarily resulting from a net loss of $227.5 million and accretion on marketable securities of $1.3 million, partially reduced by in-process research and development expenses of $150.0 million related to our exercise of the option to expand our territory under the license agreement with Joyo, which are reflected in investing activities, stock-based compensation expense of $18.1 million, changes in operating assets and liabilities of $4.7 million, and depreciation and amortization expense of $1.4 million. Net cash provided by changes in operating assets and liabilities consisted primarily of an increase in accounts payable, accrued expenses, and other current and long-term liabilities of $4.4 million and a decrease in prepaid expenses and other current and long-term assets of $1.2 million, partially offset by a decrease in operating assets and liabilities, net of $0.9 million.

Previous wording

Cash used in operating activities was $31.6 million during the three months ended March 31, 2025, primarily resulting from a net loss of $31.0 million, changes in operating assets and liabilities of $6.1 million, and accretion on marketable securities of $2.0 million, partially reduced by stock-based compensation expense of $6.7 million and depreciation and amortization expense of $0.8 million. Net cash used from changes in operating assets and liabilities consisted primarily of a decrease in accrued expenses and other current and long-term liabilities of $8.0 million, partially offset by an increase in accounts payable of $1.8 million.

Current wording

Cash used in operating activities was $52.1 million during the six months ended June 30, 2025, primarily resulting from a net loss of $64.8 million, changes in operating assets and liabilities of $6.0 million, and accretion on marketable securities of $3.5 million, partially reduced by stock-based compensation expense of $13.1 million, in-process research and development expenses of $7.5 million, which are reflected in noncash and investing activities, and depreciation and amortization expense of $1.6 million. Net cash used from changes in operating assets and liabilities consisted primarily of decreases in accrued expenses and other current and long-term liabilities of $6.6 million and operating lease assets and liabilities, net of $1.1 million, partially offset by an increase in accounts payable of $1.2 million and a decrease in prepaid expenses and other current and long-term assets of $0.5 million.

Previous wording

Net cash used in investing activities was $243.8 million during the three months ended March 31, 2026 as compared to net cash provided by investing activities of $34.3 million during the three months ended March 31, 2025. The increase in cash used in investing activities of $278.1 million was primarily the result of increases in purchases of marketable securities of $242.5 million and in-process research and development of $150.0 million, partially offset by increases in sales of marketable securities of $100.8 million and maturities of marketable securities of $13.6 million.

Current wording

Net cash used in investing activities was $224.3 million during the six months ended June 30, 2026 as compared to net cash provided by investing activities of $50.0 million during the six months ended June 30, 2025. The increase in cash used in investing activities of $274.3 million was primarily the result of increases in purchases of marketable securities of $186.0 million and in-process research and development of $144.5 million, and a decrease in maturities of marketable securities of $44.8 million, partially offset by an increase in sales of marketable securities of $100.8 million.

Previous wording

Net cash provided by financing activities was $244.7 million during the three months ended March 31, 2026 and less than $0.1 million during the three months ended March 31, 2025. During the three months ended March 31, 2026, we received $242.7 million in net proceeds for the issuance of common stock from the 2026 Offering and $2.0 million from the exercise of stock options.

Current wording

Net cash provided by financing activities was $247.7 million during the six months ended June 30, 2026 as compared to $0.5 million during the six months ended June 30, 2025. During the six months ended June 30, 2026, we received $242.7 million in net proceeds for the issuance of common stock from the January 2026 Offering, $4.6 million from the exercise of stock options, and $0.8 million from the issuance of common stock under our ESPP. During the six months ended June 30, 2025, we received $0.4 million from the issuance of common stock under our ESPP and $0.1 million from the exercise of stock options.