Relay Therapeutics (Nasdaq: RLAY) shares early zovegalisib vascular anomaly data
Rhea-AI Filing Summary
Relay Therapeutics reported initial Phase 2 ReInspire data for zovegalisib in PIK3CA‑driven vascular anomalies. As of the April 15, 2026 data cut-off, 32 adults and adolescents were enrolled across 100mg, 300mg and 400mg twice‑daily dose cohorts, with all patients remaining on treatment.
Among 20 response‑evaluable patients, 60% achieved a volumetric response, defined as at least a 20% MRI‑measured reduction in target lesion volume, and 95% experienced some lesion shrinkage. At week 12, investigator‑ and patient‑reported outcome scores showed clinical improvement in 89% and 79% of patients, respectively, while pain scores improved for 71% of pain symptoms.
Safety at 100mg and 300mg twice daily appeared manageable: 23% of patients had dose reductions, median dose intensity exceeded 99%, and only 2 patients (9%) experienced Grade 3 or higher treatment‑related adverse events, with no discontinuations due to adverse events. The 400mg twice‑daily dose showed a less favorable safety profile and has been deprioritized, while expansion cohorts are open at 300mg twice daily and 400mg once daily.
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Insights
Early Phase 2 data show encouraging efficacy and tolerability for zovegalisib in a rare, high‑need indication, but remain preliminary.
The ReInspire trial enrolled 32 adults and adolescents with PIK3CA‑driven vascular anomalies across three zovegalisib doses. Among 20 response‑evaluable patients, 60% met the prespecified volumetric response threshold and 95% had some lesion reduction, suggesting meaningful biological activity across PROS, lymphatic and venous malformations.
Patient and clinician assessments support these imaging results: 89% and 79% of patients, respectively, reported overall clinical improvement at week 12, and 71% of pain symptoms improved. At 100mg and 300mg twice daily, only 2 of 22 patients had Grade 3 or worse treatment‑related adverse events, dose reductions occurred in 23% of patients, median dose intensity exceeded 99%, and no patients discontinued for adverse events.
The company has deprioritized the less tolerable 400mg twice‑daily regimen and opened expansion cohorts at 300mg twice daily and 400mg once daily, positioning the program to refine a chronic dosing strategy. While these data are from a small, early‑phase cohort and may evolve with longer follow‑up and larger numbers, they provide an initial foundation for further development of zovegalisib in vascular anomalies alongside ongoing metastatic breast cancer studies.
8-K Event Classification
Key Figures
Key Terms
volumetric response financial
blinded independent central review financial
investigator global impression of change financial
Phase 2 ReInspire trial financial
Breakthrough Therapy designation financial
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM 8-K
CURRENT REPORT
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Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).
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Item 7.01 Regulation FD Disclosure.
On May 19, 2026, Relay Therapeutics, Inc. (the "Company") issued a press release announcing initial clinical data from the Phase 2 ReInspire trial of zovegalisib in vascular anomalies, a copy of which is furnished herewith as Exhibit 99.1 to this Current Report on Form 8-K. The Company hosted a conference call and live webcast to discuss the initial clinical data on May 19, 2026 at 8:00 a.m. E.T. The Company has made available a slide presentation to accompany the call, a copy of which is being furnished as Exhibit 99.2 to this Current Report on Form 8-K. The Company undertakes no obligation to update, supplement or amend the materials attached hereto as Exhibit 99.2.
The information in this Item 7.01, including Exhibit 99.1 and Exhibit 99.2 attached hereto, is intended to be furnished and shall not be deemed "filed" for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such filing.
Item 8.01 Other Events.
On May 19, 2026, the Company announced initial clinical data from the Phase 2 ReInspire trial of zovegalisib in vascular anomalies. The ReInspire trial is an ongoing Phase 2 study designed to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics, and efficacy of zovegalisib in adults and children with vascular anomalies driven by PIK3CA mutation.
The data reported today are from Part 1 of the study in the adults and adolescents cohort (patients 12 years or older), which featured randomized dose selection across three doses. As of the April 15, 2026 data cut-off date (the "Data Cut-Off Date"), 32 total patients were enrolled and randomized to the following dose cohorts: N=11 at 100mg twice daily ("BID"), N=11 at 300mg BID, and N=10 at 400mg BID. Of the patients enrolled, 22 had PIK3CA-related overgrowth spectrum ("PROS"), 8 had a lymphatic malformation ("LM"), and 2 had a venous malformation ("VeM"). 23 patients (72%) had prior treatment with sirolimus and/or alpelisib, which was allowed in the study.
Unless indicated otherwise, all data reported are as of the Data Cut-Off Date.
Initial Efficacy Data
Of the 32 patients enrolled, 20 have been evaluated for efficacy per volumetric response assessment by blinded independent central review ("BICR"), which is assessed by MRI every 12 weeks. The remaining 12 patients had not reached the 12-week timepoint. A response is defined by a 20% or greater reduction in target lesion(s) volume from baseline.
Of the 20 response-evaluable patients, 15 had PROS, 4 had a LM, and 1 had a VeM. Of patients with a confirmed PIK3CA mutation, 25% of patients had a kinase mutation and 55% had a non-kinase mutation, while 20% had no PIK3CA mutation documented at the time of the Data Cut-Off Date. 65% had been previously treated with alpelisib or sirolimus (35% had been treated by both). All 32 patients remained on treatment as of the Data Cut-Off Date.
For the 20 response-evaluable patients:
Initial Patient and Clinician Reported Outcomes
Clinical outcome assessments of symptoms, including investigator- and patient-global impression of change ("IGIC" and "PGIC") and pain measured by investigator assessment of disease-related signs and symptoms ("IADRSS"), are being measured as secondary endpoints in the study. IGIC, PGIC, and IADRSS measures are each a seven point, single-item scale asking patients and clinicians to rate how their condition has improved or worsened since the start of treatment.
At week 12, IGIC and PGIC scores demonstrated clinical improvement in 89% and 79% of patients, respectively, and IADRSS Pain scores demonstrated clinical improvement for 71% of pain symptoms. Clinical outcome scores across all three measures trended towards further improvement for later timepoints.
The Company has developed a fit-for-purpose patient-reported outcome tool specifically for use within the trial patient population, which is in the process of being incorporated into the ReInspire trial.
Initial Safety and Tolerability Data
The safety profile of zovegalisib was assessed across a wide dose range, spanning from 100mg BID to 400mg BID (the dose being evaluated in the ongoing Phase 3 trial in metastatic breast cancer). The overall tolerability profile was generally as expected and consistent with mutant-selective PI3Kα inhibition. Rates of treatment-related adverse events ("TRAEs") and dose modifications were proportional to dose level, allowing for further dose optimization intended to identify go-forward doses suitable for chronic treatment.
Among the 22 patients treated at 100mg and 300mg BID:
The 400mg BID dose, while not a formal maximum tolerated dose, showed a safety profile that was not optimal for this patient population and is deprioritized for further development.
Cautionary Note Regarding Forward-Looking Statements
This Current Report on Form 8-K and certain materials furnished or filed herewith contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, implied and express statements regarding the Company's strategy, business plans and focus; the progress, timing and results of the clinical development of the programs across the Company's portfolio; the progress of enrollment and timing of clinical data readouts for zovegalisib; the expected therapeutic benefits and potential, efficacy, safety and tolerability of zovegalisib, both as a monotherapy and in combination with other agents, and its other programs; the therapeutic potential of the clinical data for zovegalisib; the potential uses, implementation and development of the Company's patient-reported outcome tool; the execution of the Phase 3 ReDiscover-2 trial of zovegalisib plus fulvestrant; the execution of the frontline Phase 3 readiness activities for zovegalisib plus atirmociclib plus aromatase inhibitor as well as the timing of any such trial; the interactions with regulatory authorities and the timing of any regulatory updates or approvals, and any related actions or decisions; and the potential commercialization and market opportunity for zovegalisib. The words “may,” “might,” “will,” “could,” “would,” “should,” “plan,” “anticipate,” “intend,” “believe,” “expect,” “estimate,” “seek,” “predict,” “future,” “project,” “potential,” “continue,” “target” and similar words or expressions, or the negative thereof, are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words.
Any forward-looking statements in this Current Report on Form 8-K and certain materials furnished or filed herewith are based on management's current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this Current Report on Form 8-K and certain materials furnished or filed herewith, including, without limitation, risks associated with: the impact of global economic uncertainty, geopolitical instability and conflicts, or public health epidemics or outbreaks of an infectious disease on countries or regions in which the Company has operations or does business, as well as on the timing and anticipated results of its clinical trials, strategy, future operations and profitability; significant political, trade or regulatory developments, such as tariffs, beyond the Company's control; the delay or pause of any current or planned clinical trials or the development of the Company's drug candidates; the risk that the preliminary or interim results of its preclinical or clinical trials may not be predictive of future or final results in connection with future clinical trials of its product candidates and that interim and early clinical data may change as more patient data become available and are subject to audit and verification procedures; the Company's ability to successfully demonstrate the safety and efficacy of its drug candidates; the timing and outcome of its planned interactions with regulatory authorities; and obtaining, maintaining and protecting its intellectual property. These and other risks and uncertainties are described in greater detail in the section entitled “Risk Factors” in the Company's most recent Annual Report on Form 10-K and Quarterly Report on Form 10-Q, as well as any subsequent filings with the Securities and Exchange Commission. In addition, any forward-looking statements represent the Company's views only as of the date of this Current Report on Form 8-K and should not be relied upon as representing its views as of any subsequent date. The Company explicitly disclaims any obligation to update any forward-looking statements. No representations or warranties (expressed or implied) are made about the accuracy of any such forward-looking statements.
Item 9.01 Financial Statements and Exhibits.
99.1 |
Press release issued by Relay Therapeutics, Inc. on May 19, 2026, furnished herewith. |
99.2 |
Corporate presentation, dated May 19, 2026, furnished herewith. |
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Cover Page Interactive Data File (embedded within Inline XBRL document) |
SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.
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RELAY THERAPEUTICS, INC. |
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Date: |
May 19, 2026 |
By: |
/s/ Soo-Yeun Lim |
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Soo-Yeun Lim |
Exhibit 99.1
Relay Therapeutics Announces Initial Clinical Data Demonstrating That Zovegalisib Has Potential for Differentiated Safety and Efficacy in Patients with PIK3CA-Driven Vascular Anomalies
Promising initial efficacy data with 60% volumetric response rate across doses and 29%* at the lowest tested dose of 100mg twice daily (BID) with all patients ongoing
Interim investigator- and patient-reported outcomes show 89% and 79% of patients achieved clinical improvement at week 12, respectively, and support the potential of zovegalisib to drive clinically meaningful benefit for patients
Evaluation across a wide dose range confirms potential therapeutic window, with interim safety profile supportive of chronic dosing and no patients discontinuing treatment due to adverse events
Expansion cohorts for adults and adolescents opened at 400mg once daily (QD) and 300mg BID;
pediatric dose-finding is ongoing
Company to host conference call today, Tuesday, May 19, 2026 at 8:00 am ET
Cambridge, Mass. – May 19, 2026 – Relay Therapeutics, Inc. (Nasdaq: RLAY), a clinical-stage, small molecule precision medicine company developing potentially life-changing therapies for patients living with cancer and genetic disease, today announced initial clinical data from the Phase 2 ReInspire trial of zovegalisib in vascular anomalies signaling the advantage of PI3Kα mutant-selective inhibition. Vascular anomalies are a group of rare disorders characterized by abnormal development of blood vessels, lymphatic vessels and surrounding tissues. As of the April 15, 2026 data cut-off date, in the Part 1 dose randomization portion of the study for adults and adolescents ages 12 and up, 60% of patients achieved a volumetric response at the earliest time point (12 weeks) and nearly all patients experienced symptomatic improvement at 12 weeks while maintaining a safety and tolerability profile showing the potential for chronic use. The data are being presented at the International Society for the Study of Vascular Anomalies (ISSVA) World Congress 2026, taking place in Philadelphia.
“These data demonstrate, for the first time, the promise of PI3Kα mutant-selective inhibition for patients with vascular anomalies,” said Don Bergstrom, M.D., Ph.D., President of R&D at Relay Therapeutics. “The combination of robust volumetric responses, symptomatic improvement, and a safety profile that supports chronic dosing underscores the potential of zovegalisib to meaningfully change the treatment paradigm for this underserved population. These early results strengthen our conviction in zovegalisib’s differentiated profile and its potential ability to deliver lasting benefit for patients and families affected by vascular anomalies.”
ReInspire – Zovegalisib Study in PIK3CA-Driven Vascular Anomalies
Zovegalisib is currently being evaluated in an ongoing Phase 2 study designed to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics, and efficacy of zovegalisib in adults and children with vascular anomalies driven by PIK3CA mutations.
*After the data cut-off date, one 100mg BID patient that did not have a volumetric response as of the data cut-off date has converted to an unconfirmed response. Taking this additional response into account, the volumetric response rate across doses would be 65% and the volumetric response rate at the 100mg BID dose would be 43%.
The study consists of three age groups: Group 1 is adults and adolescents 12 years or older, Group 2 is pediatrics 6-11 years old, and Group 3 is pediatrics 2-5 years old. For each age group, there is a 3-part design: Part 1 is dose selection, Part 2 is dose expansion featuring open-label basket design with exploratory single-arm dose cohorts across various patient subpopulations, and Part 3 is potentially a randomized study.
The data reported today are from Part 1 of the study in the adults and adolescents cohort (patients 12 years or older), which featured randomized dose selection across three doses. As of the April 15, 2026 data cut-off date, 32 total patients were enrolled and randomized to the following dose cohorts: N=11 at 100mg BID, N=11 at 300mg BID, and N=10 at 400mg BID. Of the patients enrolled, 22 had PIK3CA-related overgrowth spectrum (PROS), 8 had a lymphatic malformation (LM), and 2 had a venous malformation (VeM). 23 patients (72%) had prior treatment with sirolimus and/or alpelisib, which was allowed in the study.
Expansion cohorts (Part 2) for 12 and older patients have been opened at 400mg once daily (QD) and 300mg BID and are enrolling.
Unless indicated otherwise, all data reported are as of the April 15, 2026 data cut-off date.
Initial Efficacy Data Demonstrated Meaningful Volumetric Lesion Regression
Of the 32 patients enrolled, 20 have been evaluated for efficacy per volumetric response assessment by blinded independent central review (BICR), which is assessed by MRI every 12 weeks. The remaining 12 patients had not reached the 12-week timepoint. A response is defined by a 20% or greater reduction in target lesion(s) volume from baseline.
Of the 20 response-evaluable patients, 15 had PROS, 4 had a LM, and 1 had a VeM. Of patients with a confirmed PIK3CA mutation, 25% of patients had a kinase mutation and 55% had a non-kinase mutation, while 20% had no PIK3CA mutation documented at the time of data cut-off. 65% had been previously treated with alpelisib or sirolimus (35% had been treated by both). All 32 patients remained on treatment as of the data cut-off date.
For the 20 response-evaluable patients:
Initial Patient and Clinician Reported Outcomes Showed Meaningful Clinical Improvement at 12 Weeks
Clinical outcome assessments of symptoms, including investigator- and patient-global impression of change (IGIC and PGIC) and pain measured by investigator assessment of disease-related signs and symptoms (IADRSS), are being measured as secondary endpoints in the study. IGIC, PGIC, and IADRSS measures are each a seven point, single-item scale asking patients and clinicians to rate how their condition has improved or worsened since the start of treatment.
At week 12, IGIC and PGIC scores demonstrated clinical improvement in 89% and 79% of patients, respectively, and IADRSS Pain scores demonstrated clinical improvement for 71% of pain symptoms. Clinical outcome scores across all three measures trended towards further improvement for later timepoints.
Relay Therapeutics has developed a fit-for-purpose patient-reported outcome (PRO) tool specifically for use within the trial patient population, which is in the process of being incorporated into the ReInspire trial.
Initial Safety and Tolerability Data Demonstrated a Clear Path to Identifying a Chronic Dose of Zovegalisib
The safety profile of zovegalisib was assessed across a wide dose range, spanning from 100mg BID to 400mg BID (the dose being evaluated in the ongoing Phase 3 trial in metastatic breast cancer). The overall tolerability profile was generally as expected and consistent with mutant-selective PI3Kα inhibition. Rates of treatment-related adverse events (TRAEs) and dose modifications were proportional to dose level, allowing for further dose optimization intended to identify go-forward doses suitable for chronic treatment.
Among the 22 patients treated at 100mg and 300mg BID:
The 400mg BID dose, while not a formal maximum tolerated dose, showed a safety profile that was not optimal for this patient population and is deprioritized for further development.
Anticipated Next Steps
Data Presentation and Conference Call Information
Relay Therapeutics will host a conference call and live webcast today, May 19, at 8:00 a.m. ET. Registration and dial-in for the conference call, as well as the data presentation, may be accessed through Relay Therapeutics’ website under Events in the News & Events section through the following link: https://ir.relaytx.com/news-events/events-presentations. An archived replay of the webcast will be available following the event. An abstract for these data will be presented tomorrow, May 20 from 4:45pm-4:49pm ET. No additional or new data will be in the presentation.
About Vascular Anomalies
Vascular anomalies (VAs) are a group of rare disorders characterized by abnormal development of blood vessels, lymphatic vessels and surrounding tissues. These conditions can vary widely in presentation and severity and may cause chronic pain, swelling, disfigurement, impaired mobility, bleeding and other serious complications that can significantly impact quality of life. PIK3CA-driven vascular anomalies are a subset of these disorders caused by mutations in the PIK3CA gene, including conditions such as PIK3CA-related overgrowth spectrum, lymphatic malformations and venous malformations. Approximately 170,000 patients in the U.S. are estimated to be living with PIK3CA-driven vascular anomalies. Current systemic treatment options are limited and may be associated with tolerability challenges that can restrict long-term use.
About Zovegalisib
Zovegalisib is the lead investigational program in Relay Therapeutics’ efforts to discover and develop mutant-selective inhibitors of PI3Kα, the most frequently mutated kinase in all cancers and all vascular anomalies. Zovegalisib has the potential, if approved, to address a significant portion of the approximately 140,000 patients with HR+/HER2- breast cancer with a PI3Kα mutation and the estimated 170,000 patients with vascular anomalies driven by a PI3Kα mutation per year in the United States, one of the largest patient populations for a precision medicine.
Traditionally, the development of PI3Kα inhibitors has focused on the active, or orthosteric, site. The therapeutic index of orthosteric inhibitors is limited by the lack of clinically meaningful selectivity for mutant versus wild-type (WT) PI3Kα and off-isoform activity. Toxicity related to inhibition of WT PI3Kα and other PI3K isoforms results in sub-optimal inhibition of mutant PI3Kα with reductions in dose intensity and frequent discontinuation. The Dynamo® platform enabled the discovery of zovegalisib, the first known allosteric, pan-mutant, and isoform-selective PI3Kα inhibitor, designed to overcome these
limitations. Relay Therapeutics solved the full-length cryo-EM structure of PI3Kα, performed computational long time-scale molecular dynamic simulations to elucidate conformational differences between WT and mutant PI3Kα, and leveraged these insights to support the design of zovegalisib. Zovegalisib is currently being evaluated in multiple metastatic breast cancer studies and a first-in-human study designed to treat patients with PIK3CA mutation driven vascular anomalies. For more information on zovegalisib, please visit here.
About Relay Therapeutics
Relay Therapeutics (Nasdaq: RLAY) is a clinical-stage, small molecule precision medicine company developing potentially life-changing therapies for patients living with cancer and genetic disease. Relay Therapeutics’ Dynamo® platform integrates an array of leading-edge computational and experimental approaches designed to drug protein targets that have previously been intractable or inadequately addressed. The company’s lead clinical asset, zovegalisib, is the first pan-mutant selective PI3Kα inhibitor to enter clinical development and is currently in a Phase 3 clinical trial (ReDiscover-2) in HR+/HER2- metastatic breast cancer. Zovegalisib is also being investigated in a group of genetic disease indications called PIK3CA-driven vascular anomalies. Relay Therapeutics’ pipeline also includes programs for NRAS-driven solid tumors and Fabry disease. For more information, please visit www.relaytx.com or follow us on LinkedIn.
Cautionary Note Regarding Forward-Looking Statements
This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, implied and express statements regarding Relay Therapeutics’ strategy, business plans and focus; the progress, timing and results of the clinical development of the programs across Relay Therapeutics’ portfolio; the progress of enrollment and timing of clinical data readouts for zovegalisib; the expected therapeutic benefits and potential, efficacy, safety and tolerability of zovegalisib, both as a monotherapy and in combination with other agents, and its other programs; the therapeutic potential of the clinical data for zovegalisib; the potential uses, implementation and development of Relay Therapeutics’ patient-reported outcome tool; the execution of the Phase 3 ReDiscover-2 trial of zovegalisib + fulvestrant; the execution of the frontline Phase 3 readiness activities for zovegalisib + atirmociclib + aromatase inhibitor as well as the timing of any such trial; the interactions with regulatory authorities and the timing of any regulatory updates or approvals, and any related actions or decisions; and the potential commercialization and market opportunity for zovegalisib. The words “may,” “might,” “will,” “could,” “would,” “should,” “plan,” “anticipate,” “intend,” “believe,” “expect,” “estimate,” “seek,” “predict,” “future,” “project,” “potential,” “continue,” “target” and similar words or expressions, or the negative thereof, are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words.
Any forward-looking statements in this press release are based on management's current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this press release, including, without limitation, risks associated with: the impact of global economic uncertainty, geopolitical instability and conflicts, or public health epidemics or outbreaks of an infectious disease on countries or regions in which Relay Therapeutics has operations or does business, as well as on the timing and anticipated results of its clinical trials, strategy, future operations and profitability; significant political, trade or regulatory developments, such as tariffs,
beyond Relay Therapeutics’ control; the delay or pause of any current or planned clinical trials or the development of Relay Therapeutics’ drug candidates; the risk that the preliminary or interim results of its preclinical or clinical trials may not be predictive of future or final results in connection with future clinical trials of its product candidates and that interim and early clinical data may change as more patient data become available and are subject to audit and verification procedures; Relay Therapeutics’ ability to successfully demonstrate the safety and efficacy of its drug candidates; the timing and outcome of its planned interactions with regulatory authorities; and obtaining, maintaining and protecting its intellectual property. These and other risks and uncertainties are described in greater detail in the section entitled “Risk Factors” in Relay Therapeutics’ most recent Annual Report on Form 10-K and Quarterly Report on Form 10-Q, as well as any subsequent filings with the Securities and Exchange Commission. In addition, any forward-looking statements represent Relay Therapeutics' views only as of the date of this press release and should not be relied upon as representing its views as of any subsequent date. Relay Therapeutics explicitly disclaims any obligation to update any forward-looking statements. No representations or warranties (expressed or implied) are made about the accuracy of any such forward-looking statements.
Contact:
Mitch Maisel
mmaisel@relaytx.com
Media:
Katie Engleman
1AB
919-333-7722
katie@1abmedia.com
Vascular Anomalies Update May 2026 Exhibit 99.2
Disclaimer This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, implied and express statements regarding the progress, timing and results of the clinical development of the programs across our portfolio, including the expected timing of data readout and other clinical and developmental milestones; the expected therapeutic benefits of our programs, and potential safety, efficacy and tolerability; the potential of our product candidates, including zovegalisib, to address a major unmet medical need; expectations regarding our pipeline and operating plan; the competitive landscape and potential commercialization and market opportunities for our product candidates; expectations regarding current and future interactions with the U.S. Food and Drug Administration (FDA) or other regulatory authorities and the timing of any regulatory updates or approvals, and any related actions or decisions; our plans to develop, manufacture and commercialize our current product candidates; the potential to combine zovegalisib with other products; and the implementation of our business model and strategic plans for our business, current product candidates and any future product candidates. The words “may,” “might,” “will,” “could,” “would,” “should,” “plan,” “anticipate,” “intend,” “believe,” “expect,” “estimate,” “seek,” “predict,” “future,” “project,” “potential,” “continue,” “target” and similar words or expressions, or the negative thereof, are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements in this presentation are based on management's current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this presentation, including, without limitation, risks associated with: the impact of global economic uncertainty, geopolitical instability and conflicts, or public health epidemics or outbreaks of an infectious disease on countries or regions in which we have operations or do business; significant political, trade, or regulatory developments, such as tariffs, beyond our control; the timing and anticipated results of our clinical trials, strategy, future operations and profitability; the delay or pause of any current or planned clinical trials or the development of our drug candidates; the risk that the preliminary results of our preclinical or clinical trials may not be predictive of future or final results in connection with future clinical trials of our product candidates; our ability to successfully demonstrate the safety and efficacy of our drug candidates; the timing and outcome of our planned interactions with regulatory authorities; and obtaining, maintaining and protecting our intellectual property. These and other risks, uncertainties and important factors are described in the section entitled "Risk Factors" in our most recent Annual Report on Form 10-K and Quarterly Report on Form 10-Q, as well as any subsequent filings with the Securities and Exchange Commission. Any forward-looking statements represent our views only as of the date of this presentation and we undertake no obligation to update or revise any forward-looking statements, whether as a result of new information, the occurrence of certain events or otherwise. We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. No representations or warranties (expressed or implied) are made about the accuracy of any such forward-looking statements. Certain information contained in this presentation relates to or is based on studies, publications, surveys and other data obtained from third-party sources and our own internal estimates and research. While we believe these third-party studies, publications, surveys and other data to be reliable as of the date of this presentation, we have not independently verified, and make no representation as to the adequacy, fairness, accuracy or completeness of, any information obtained from third-party sources. In addition, no independent source has evaluated the reasonableness or accuracy of our internal estimates or research and no reliance should be made on any information or statements made in this presentation relating to or based on such internal estimates and research. This presentation contains trademarks, trade names and service marks of other companies, which are the property of their respective owners.
Zovegalisib – Potential to Address 3 Large Commercial Opportunities $2-3B $7-8B $6-8B 2L Breast Cancer 1L Breast Cancer Vascular Anomalies Note: TAM calculated based on market benchmarks and internal analysis Estimated US TAM
2L Breast Cancer – Ph1/2 Data at Ph3 Dose Showed Clinically Meaningful PFS 2L Breast Cancer $2-3B Capivasertib + Fulv (4 days on, 3 off) Zovegalisib + Fulv 400mg BID (Phase 3 Dose) Ph3 regimens Zovegalisib shows favorable efficacy in 2L+ patients Interim zovegalisib data support ongoing Phase 3 trial against capivasertib 2L & 3L+ Post-CDK4/6 ORR: 43% ORR: 26% 5.5mo mPFS 11.1mo mPFS 11.2mo in Kinase | 11.0mo in Non-Kinase 1. TAM calculated based on market benchmarks and internal analysis; Sources: ReDiscover Ph1/2 preliminary data as of 1/13/2026; Capi + fulv Ph3 data from CAPItello-291, Turner N Engl J Med 2023; 388:2058-2070. Note: These data are derived from different clinical trials at different points in time, with differences in molecule composition, trial design and patient populations. As a result, cross-trial comparisons cannot be made, and no head-to-head clinical trials have been conducted. Estimated US TAM1 ReDiscover preliminary data as of 01/13/2026
1L Breast Cancer – Establishing Zovega + Atirmo + AI Combinability for 1L Use 44% ORR Standard of Care CDK4/6 + ET vs. 40% Gr3+ AE 50-90% Gr3+ AE vs. Zovega + Atirmo + AI selected as go-forward 1L regimen; Supply agreement signed with Pfizer for atirmo; Trial intended to initiate in early 2027 Efficacy Tolerability Zovega + Atirmo + ET Triplet Doublet ReDiscover preliminary data as of 04/13/2026 53-55% ORR Study Population 1L Patients Median 3L Patients vs. 1L Breast Cancer $7-8B Estimated US TAM1 1. TAM calculated based on market benchmarks and internal analysis; Note: These data are derived from different clinical trials at different points in time, with differences in molecule composition, trial design and patient populations. As a result, cross-trial comparisons cannot be made, and no head-to-head clinical trials have been conducted.
Vascular Anomalies – Zovega’s Promising Initial Efficacy Data & Tolerability Profile Vascular Anomalies $6-8B Initial Efficacy Data Initial Tolerability Data Zovegalisib All doses ReInspire, (N=20) ReInspire median follow-up: 14 weeks 250mg EPIK-P14 (N=37) 125mg EPIK-P25 (N=54) Alpelisib ~180mg6 EPIK-P2 (N=54) ~220mg7 EPIK-B57 (N=188) Alpelisib 60% VRR2 400mg: 57% 300mg: 100% 100mg: 29%3 Zovegalisib All doses ReInspire, (N=32) Gr3 hyperglycemia: 1 pt (3%) (pre-diabetic pt at 400mg) Lower Gr3+ TRAEs Greater volumetric response rates Closest approx. of safety at Vijoice label dose7 Volumetric Response Rate (VRR) Gr3+ AEs Estimated US TAM1 ReInspire preliminary data as of 04/15/2026 1. TAM calculated based on market benchmarks and internal analysis; 2. Includes both confirmed and unconfirmed responses. 3. After the data cut-off date, one 100mg BID patient that did not have a volumetric response as of the data cut-off date has converted to an unconfirmed response, resulting in a 100mg BID volumetric response rate of 43% (3/7), a volumetric response rate of 69% (9/13) for patients treated at 300mg BID or 100mg BID, and a volumetric response rate of 65% (13/20) across doses. None of the other response-evaluable patients’ response statuses have changed since the data cut-off date; 4. EPIK-P1 as cited in Vijoice FDA label, label dose is 250mg QD; 5. EPIK-P2: Canaud 2024 Blood 144:5512 and results from clintrials.gov listing, 125mg QD was starting dose; 6. 180mg dose approximated from rates of dose escalation after week 26 listed on clintrials.gov listing; 7. EPIK-B5: SABCS 2025 #RF7-02, 220mg dose approximated from dose modification data; Gr3 TRAEs = Grade 3+ Treatment-Related Adverse Events, IGIC = Investigator Global Impression of Change scale, SD = Stable Disease, uVR = unconfirmed volumetric response. Note: These data are derived from different clinical trials at different points in time, with differences in molecule composition, trial design and patient populations. As a result, cross-trial comparisons cannot be made, and no head-to-head clinical trials have been conducted. SAE rate wk24 89% of patients with investigator-reported clinical improvement (IGIC at week 12) One 100mg pt converted from SD to uVR after data cut-off3
~170k US patients with PIK3CA-driven Vascular Anomalies leading to vascular anomalies drives malformed vasculature Somatic PIK3CA mutation Vascular Anomalies Overview Local Treatments: temporary, only treat symptoms Systemic Treatments: non-selective, limited toxicity/efficacy Large unmet medical need Current treatment options are limited First mutant-selective PI3Kα inhibitor Potential for chronic systemic treatment option Zovegalisib is uniquely positioned to address driver of disease Selectivity Tolerability Efficacy PIK3CA mut Sources: ISSVA classification, NORD, Mayo Clinic, Novartis, Penington et al 2023, Gallagher et al 2022, Luks et al 2015, Limaye et al 2015, Peyre et al 2021, Hong et al 2021, and company primary market research Initial clinical data showing: PIK3CA-Driven Vascular Anomalies
Vascular Anomalies – Patient Numbers ~60-65k US patients ~5-10k US patients 25-30% seek systemic tx 20-25% seek systemic tx ~20-25k US patients 15-20% seek systemic tx ~50-70k US patients 25-30% seek systemic tx PIK3CA-driven Vascular Anomalies (VAs) ~170k US patients PIK3CA-Related Overgrowth Spectrum (PROS) PIK3CA-driven Lymphatic Malformations (LM) PIK3CA-driven Venous Malformations (VeM) PIK3CA-driven Cerebral Cavernous Malformations (CCM) Vascular Anomaly Subtypes Sources: ISSVA classification, NORD, Mayo Clinic, Novartis, Penington et al 2023, Gallagher et al 2022, Luks et al 2015, Limaye et al 2015, Peyre et al 2021, Hong et al 2021, and company primary market research Initial clinical focus: ~25k US patients seeking systemic therapy PIK3CA-Driven Vascular Anomalies
Zovegalisib – Study Design: ReInspire Part 1: Dose Selection Part 2: Dose Expansion Expansion cohorts opened at: 300mg BID 400mg QD Randomized dose finding: 400mg, 300mg, 100mg BID (Completed; N=~10 each) Data shown today RP2D(s) RP2D(s) Expansion Cohort(s) Enrollment open in adults & adolescents in part 2 and pediatrics (6-11 y/o) in part 1 PIK3CA-Driven Vascular Anomalies RP2D(s) Expansion Cohort(s) Dose Escalation (opened Q1 2026) Dose Escalation (not yet opened) Adults & Adolescents (≥12 years old) Pediatrics (6-11 years old) Pediatrics (2-5 years old)
Zovegalisib – ReInspire Trial Demographics Total (N=32) 100mg BID (N=11) 300mg BID (N=11) 400mg BID (N=10) Age (years), median (range) 24.5 (12, 63) 31 (13, 50) 24 (13, 54) 19.5 (12, 63) 12-17 / ≥18, n (%) 10 (31) / 22 (69) 4 (36) / 7 (64) 2 (18) / 9 (82) 4 (40) / 6 (60) Sex, M/F, n (%) 14 (44) / 18 (56) 6 (55) / 5 (45) 5 (45) / 6 (55) 3 (30) / 7 (70) Disease Classification, n (%) PROS 22 (69) 8 (73) 6 (54) 8 (80) CLOVES 5 (16) 1 (9) 3 (27) 1 (10) KTS 10 (31) 4 (36) 2 (18) 4 (40) Other 7 (22) 3 (27) 1 (9) 3 (30) LM 8 (25) 3 (27) 4 (36) 1 (10) VeM 2 (6) 0 1 (9) 1 (10) Performance Status at Baseline, 50-70/ ≥801, n (%) 5 (16) / 27 (84) 2 (18) / 9 (82) 1 (9) / 10 (91) 2 (20) / 8 (80) Pre-diabetic2, n (%) 8 (25) 1 (9) 6 (55) 1 (10) Local PIK3CA Status at Baseline, n (%) Kinase mutation 10 (31) 4 (36) 4 (36) 2 (20) Non-Kinase mutation 16 (50) 4 (36) 6 (55) 6 (60) No mutation documented 6 (19) 3 (27) 1 (9) 2 (20) Prior disease-related systemic treatment, median 1 1 2 1 None, n (%) 9 (28) 3 (27) 3 (27) 3 (30) Prior alpelisib / sirolimus, n (%) 23 (72) 8 (73) 8 (73) 7 (70) Prior disease-related surgery, n (%) 19 (59) 5 (45) 6 (55) 8 (80) Prior catheter-based procedures, n (%) 18 (56) 6 (55) 8 (73) 4 (40) 1. Lansky performance status for patients <16 years old or Karnofsky performance status for patients ≥16 years old; 2. Baseline HbA1c ≥5.7, glucose ≥100, or medical history of pre-diabetes mellitus ReInspire preliminary data as of 04/15/2026 PIK3CA-Driven Vascular Anomalies
Zovegalisib – All Initial Doses Resulted in Exposures Projected to be Active PIK3CA-Driven Vascular Anomalies ReInspire preliminary data as of 04/15/2026 C1D15 Mean Concentration-Time Profiles By Dose 400mg BID (N=7) 300mg BID (N=6) 100mg BID (N=6)
Zovegalisib – 60% Volumetric Response Rate by BICR Across All Doses PIK3CA-Driven Vascular Anomalies 60% Overall VRR (12/20)1 Across All Doses VRR by dose: 400mg BID: 57% (4/7) 300mg BID: 100% (6/6) 100mg BID: 29% (2/7)2 1. Includes both confirmed and unconfirmed responses. 2. After the data cut-off date, one 100mg BID patient that did not have a volumetric response as of the data cut-off date has converted to an unconfirmed response, resulting in a 100mg BID volumetric response rate of 43% (3/7), a volumetric response rate of 69% (9/13) for patients treated at 300mg BID or 100mg BID, and a volumetric response rate of 65% (13/20) across doses. None of the other response-evaluable patients’ response statuses have changed since the data cut-off date. Volumetric Response (VR) = 20% or greater reduction in target lesion volume by blinded independent central review (BICR); cVR = Confirmed Volumetric Response (VR with 2nd scan to confirm response), uVR = Unconfirmed Volumetric Response (VR without confirmatory scan), SD = Stable Disease Best % Change from Baseline of Target lesion(s) volume Volumetric Response: ≥20% reduction ReInspire preliminary data as of 04/15/2026 % Change from Baseline VeM Three 100mg pts with lesion reduction between 18.2-19.8% Patient converted to unconfirmed response after data cut-off2
Zovegalisib – Volumetric Response Over Time (BICR) PIK3CA-Driven Vascular Anomalies 60% Overall VRR (12/20)1 Three 100mg pts with lesion reduction between 18.2-19.8% (all ongoing) All patients ongoing ReInspire preliminary data as of 04/15/2026 400mg VRR: 57% (4/7) 300mg VRR: 100% (6/6) 100mg VRR: 29% (2/7)1 1. Includes both confirmed and unconfirmed responses. 2. After the data cut-off date, one 100mg BID patient that did not have a volumetric response as of the data cut-off date has converted to an unconfirmed response, resulting in a 100mg BID volumetric response rate of 43% (3/7), a volumetric response rate of 69% (9/13) for patients treated at 300mg BID or 100mg BID, and a volumetric response rate of 65% (13/20) across doses. None of the other response-evaluable patients’ response statuses have changed since the data cut-off date. *Patient converted to unconfirmed response after data cut-off2 * Reductions generally deepened over time at all doses
12 wk 20 wk 12 wk 20 wk 12 wk 20 wk Zovegalisib – Initial Efficacy Data Supports Clear Symptomatic Benefit Investigator-Reported (IGIC) Patient-Reported (PGIC) Pain (IADRSS) Very much improved Very much worsened IGIC = Investigator Global Impression of Change, PGIC = Patient Global Impression of Change, IADRSS = Investigator Assessment of Disease-Related Signs and Symptoms. Note: N for IGIC and PGIC is number of patients; N for IADRSS pain is number of most bothersome pain symptoms, where some patients may have more than one pain symptom. Scale: +3 very much improved, +2 minimally improved, +1 minimally improved, 0 no change, -1 minimally worse, -2 much worse, -3 very much worse 100mg BID 300mg BID 400mg BID 89% of patients improved by week 12 79% of patients improve by week 12 71% of pain symptoms improved by week 12 N = 19 N = 11 N = 14 N = 10 N = 14 N = 21 Mean Change by timepoint Mean Change by timepoint Mean Change by timepoint ReInspire preliminary data as of 04/15/2026 No Change PIK3CA-Driven Vascular Anomalies
Zovegalisib – Initial Efficacy Data Summary 29%2 100mg BID (N=7) 300mg BID (N=6) 400mg BID (N=7) 60% Overall VRR (12/20)1 Zovega Overall PROS Non-PROS4 Kinase Non-Kinase Unknown Prior alp/siro No Prior alp/siro Ages 18+ Ages 12-17 60%1 Alpelisib3 17-27% Subgroup VRR1 Consistent Across Subgroups Broad Symptomatic Benefit IGIC PGIC IADRSS Pain5 % of Patients with Improvement at Week 12 Meaningful Efficacy Data 1. Includes both confirmed and unconfirmed responses. 2. After the data cut-off date, one 100mg BID patient that did not have a volumetric response as of the data cut-off date has converted to an unconfirmed response, resulting in a 100mg BID volumetric response rate of 43% (3/7), a volumetric response rate of 69% (9/13) for patients treated at 300mg BID or 100mg BID, and a volumetric response rate of 65% (13/20) across doses. None of the other response-evaluable patients’ response statuses have changed since the data cut-off date; 3. EPIK-P1: Vijoice FDA label and EPIK-P2: Canaud 2024 Blood 144:5512; 4. Non-PROS = LM and VeM; 5. IADRSS rate shown is percentage of pain symptoms improved; Alp = alpelisib, Siro = sirolimus; IGIC = Investigator Global Impression of Change, PGIC = Patient Global Impression of Change, IADRSS = Investigator Assessment of Disease-Related Signs and Symptoms, SD = Stable Disease, uVR = unconfirmed volumetric response. Note: These data are derived from different clinical trials at different points in time, with differences in molecule composition, trial design and patient populations. As a result, cross-trial comparisons cannot be made, and no head-to-head clinical trials have been conducted. ReInspire preliminary data as of 04/15/2026 3 of 7 pts with lesion reduction 18.2-19.8% Volumetric Response Rate (VRR) PIK3CA-Driven Vascular Anomalies One 100mg pt converted from SD to uVR after data cut-off2
100mg BID (N=11) All Gr Gr1 Gr2 Gr3+ Any TRAE 82% 36% 45% - Headache 18% 18% - - Fatigue 18% 9% 9% - Nausea 27% 18% 9% - Diarrhea 27% 27% - - Hyperglycemia - - - - Decreased appetite 18% 9% 9% - Rash - - - - Stomatitis - - - - Zovegalisib – Treatment-Related Adverse Events ≥15% of Patients No discontinuations due to adverse events 300mg BID (N=11) All Gr Gr1 Gr2 Gr3+ 91% 55% 18% 18% 73% 73% - - 55% 36% 18% - 45% 36% 9% - 18% 18% - - 45% 18% 27% - 18% 9% 9% - - - - - - - - - 100mg+300mg BID (N=22) All Gr Gr1 Gr2 Gr3+ 86% 45% 32% 9% 45% 45% - - 36% 23% 14% - 36% 27% 9% - 23% 23% - - 23% 9% 14% - 18% 9% 9% - - - - - - - - - 400mg BID (N=10) All Gr Gr1 Gr2 Gr3+ 90% 20% 50% 20% 50% 30% 20% - 20% 10% 10% - 70% 40% 30% - 10% - 10% - 40% 20% 10% 10% 20% 10% 10% - - - - - - - - - PIK3CA-Driven Vascular Anomalies Majority of hyperglycemia observed in patients prediabetic at baseline1 Median Relative Dose Intensity 100% Dose Reduction due to TRAE, n (%) 1 (9%)2 99% 4 (36%) 99% 5 (23%) 77% 7 (70%) 1. Baseline HbA1c ≥5.7, glucose ≥100, or medical history of pre-diabetes mellitus; 2. Patient later increased back up to original dose of 100mg BID ReInspire preliminary data as of 04/15/2026 TRAE ≥15% Other select TRAE No Grade 3 hyperglycemia
Data benchmark EPIK-B51 (N=188) ReInspire (N=22) mDoE 5.6mo mDoE 3.5mo mDoE Hyperglycemia Diarrhea Rash2 Stomatitis3 PI3Kα Inhibitors – Tolerability Profile Across Known Key Pathway AEs Gr1-2 Gr3+ Zovegalisib 100mg + 300mg BID Alpelisib ~220mg QD1 2% 73% 51% 42% 38% 0% 0% ReInspire preliminary data as of 04/15/2026 PIK3CA-Driven Vascular Anomalies At 100mg and 300mg BID: No rash or stomatitis of any grade No Gr3 hyperglycemia or diarrhea No discontinuations Median dose intensity >99% 1. EPIK-B5, SABCS 2025 #RF7-02, 220mg dose approximated from dose modification data; 2. Rash for alpelisib references the cumulative sum of rates of rash and rash maculo-papular from the EPIK-B5 study, and may include overlap; 3. Stomatitis for alpelisib references the cumulative sum of rates of stomatitis and mucosal inflammation from the EPIK-B5 study, and may include overlap; 4. Pre-diabetic: baseline HbA1c ≥5.7 to <6.5, glucose ≥100, or medical history of pre-diabetes mellitus; 5. EPIK-P1 is a retrospective study, label dose is 250mg QD, and EPIK-P2: Canaud 2024 Blood 144:5512, 125mg QD was starting dose. Note: These data are derived from different clinical trials at different points in time, with differences in molecule composition, trial design and patient populations. As a result, cross-trial comparisons cannot be made, and no head-to-head clinical trials have been conducted. ` No hyperglycemia at 100mg At 300mg, 55% of patients were pre-diabetic at baseline4, and the majority of hyperglycemia was observed in these patients EPIK-P1 (250mg) was not a prospective study and EPIK-P2 was conducted at half the label dose5
Patient Vignette – Adult Patient with PROS Achieved Meaningful Clinical and Radiographical Improvement with Zovega 100mg BID PIK3CA-Driven Vascular Anomalies 44-year-old male with KTS (PROS) PIK3CA mutation: Q546K Prior sclerotherapy x3, no prior systemic tx Minimal mobility at baseline Dosed with 100mg zovegalisib 19.8% volumetric reduction at week 24 (13% reduction seen at week 12) 3.6 liter lesion reduction Deepening reduction at each scan Baseline Week 24 18 liter lesion at baseline 3.6 liter reduction (-19.8%) at 24wk Dramatic and rapid clinical improvement “Much Improved” IGIC overall status Investigator Global Impression of Change Tolerable profile allowing for prolonged dosing No dose modifications Patient remains on therapy at 100mg BID “The participant used to not be able to walk further than front door to car. Within 2 weeks, he walked around the block.” - ReInspire Investigator Note: Symptom improvement shown here is for Week 24 ReInspire preliminary data as of 04/15/2026 The information presented on the slide may not be representative of all patient experiences
Patient Vignette – Previously Systemically Treated Pediatric Patient with PROS Achieved Meaningful Radiographic & Clinical Improvement with Zovega 300mg BID PIK3CA-Driven Vascular Anomalies 12-year-old male with CLOVES (PROS) PIK3CA mutation: E542K Prior surgery x6, laser therapy x12, sirolimus (no response) and alpelisib Painful chest lesion, with lymphatic leakage Dosed with 300mg zovegalisib 55% volumetric reduction at week 24 (49% reduction seen at week 12) Dramatic and rapid clinical improvement “Much Improved” IGIC overall status Investigator Global Impression of Change Tolerable profile allowing for prolonged dosing No dose modifications Patient remains on therapy at 300mg BID Note: Symptom improvement shown here is for Week 24 ReInspire preliminary data as of 04/15/2026 The information presented on the slide may not be representative of all patient experiences Baseline Week 24 "After initiation of zovegalisib, the patient has experienced a marked reduction in overgrowth size, improved clothing fit, and decreased sensitivity of affected areas. Episodes of drainage and cellulitis have resolved, and previously painful stimuli such as ECG sticker placement are now well tolerated." - ReInspire Investigator Deepening reduction at each scan
Patient Vignette – Adult patient with Facial LM Experienced Meaningful Improvement in Pain and Radiographic Response with Zovega 300 mg BID PIK3CA-Driven Vascular Anomalies 42-year-old female with facial LM PIK3CA mutation: E545K Prior sclerotherapy x3, embolization x2, surgery x4, sirolimus (no response, dc for AEs) & alpelisib (improvement, but dc for AEs) Dosed with 300mg zovegalisib 53% volumetric reduction at week 24* (31% reduction seen at week 12) Deepening reduction at each scan Dramatic and rapid clinical improvement “Much Improved” IGIC overall status Investigator Global Impression of Change Tolerable profile allowing for prolonged dosing No dose modifications Patient remains on therapy at 300mg BID Note: Symptom improvement shown here is for Week 24 The information presented on the slide may not be representative of all patient experiences “She had a meaningful decrease in pain and fullness” - ReInspire Investigator Week 24 Baseline Ear pain Much improved Oral pain Jaw pain No change Most bothersome symptoms: (Investigator Assessment of Disease-Related Signs and Symptoms) Minimally improved *Week 24 scan provided after data cutoff ReInspire preliminary data as of 04/15/2026
Zovegalisib - Clear Path to Finding Dose to Evaluate Potential for Differentiated Profile Zovegalisib Alpelisib 29%7 0% 100mg BID (N=7) 400mg QD 300mg BID (N=6) 400mg BID (N=7) 100mg BID (N=11) 400mg QD 300mg BID (N=11) 400mg BID (N=10) 250mg EPIK-P1 (SAE) ~180mg3 EPIK-P22 (SAE) ~220mg4 EPIK-B54 (+fulv) (Gr3+ AE) 250mg EPIK-P11 (N=37) 125mg EPIK-P22 (N=54) Efficacy Data: Volumetric response rate6 Safety Data: Gr3+ TRAE Selected as Expansion Doses ReInspire preliminary data as of 04/15/2026 PIK3CA-Driven Vascular Anomalies Expansion dose (I)5 Expansion dose (I)5 wk24 wk24 Expansion dose (II) Expansion dose (II) 1. EPIK-P1: FDA review document; 2. EPIK-P2: Canaud 2024 Blood 144:5512 and results from clintrials.gov listing, 125mg QD was starting dose; 3. 180mg dose approximated from rates of dose escalation after week 26 listed on clintrials.gov listing; 4. EPIK-B5: SABCS 2025 #RF7-02, 220mg dose approximated from dose modification data; 5. 400mg QD expansion cohort yet to be initiated; 6. ReInspire VRR Includes both confirmed and unconfirmed responses. 7. After the data cut-off date, one 100mg BID patient that did not have a volumetric response as of the data cut-off date has converted to an unconfirmed response, resulting in a 100mg BID volumetric response rate of 43% (3/7), a volumetric response rate of 69% (9/13) for patients treated at 300mg BID or 100mg BID, and a volumetric response rate of 65% (13/20) across doses. None of the other response-evaluable patients’ response statuses have changed since the data cut-off date. SD = Stable Disease, uVR = unconfirmed volumetric response. Note: These data are derived from different clinical trials at different points in time, with differences in molecule composition, trial design and patient populations. As a result, cross-trial comparisons cannot be made, and no head-to-head clinical trials have been conducted. One 100mg pt converted from SD to uVR after data cut-off7
Potential for Accelerated Approval Pathway* *Illustrative and subject to discussion with the U.S. Food and Drug Administration PIK3CA-Driven Vascular Anomalies Potential Accelerated Approval dataset Basket of: PROS LMs VeMs Adults & Adolescents (≥12 years old) Pediatrics (6-11 years old) Dose Selection Dose Expansion Confirmatory Add’l pt at RP3D Dose Escalation Expansion Pediatrics (2-5 years old) Potential Dose Escalation Start 300mg BID 400mg QD 400mg BID 100mg BID 300mg BID Dose Randomization:
Vascular Anomalies – Mutant-Selective Approach Has Potential to Unlock Significant Market Target Profile of Zovegalisib 1. TAM calculated based on market benchmarks and internal analysis Potential Commercial Implications Significant market opportunity $6-8B Estimated US TAM1 Superior Efficacy Superior Tolerability Superior Activity across VAs Greater Penetration Greater Chronicity Greater Breadth of use
Relay Tx – Clear Path to Addressing Large Commercial Opportunities 2L Breast Cancer 1L Breast Cancer Vascular Anomalies Zovegalisib granted BTD ~$2-3B TAM2 ~$7-8B TAM ~$6-8B TAM Capi+fulv in 2L: 5.5mo mPFS Alpelisib & KP-001 11-16% VRR3 at week 12 & 16 CDK+ET in 2L+ 14-32% ORR 11.1mo mPFS at pivotal dose Rapid execution of ongoing 2L pivotal trial 60% VRR across all doses4 Enrolling adult expansion; pediatric cohort open 44% ORR in median 3L patients for Zovega + Atirmo + fulv triplet Aim to initiate 1L pivotal trial in early 2027 Anticipated Next Steps Anticipated 2026 disclosures key value drivers Zovegalisib Program Hurdle1 Clinical Benchmark Phase 3 enrollment update by YE2026 Data and regulatory update by YE2026 Regulatory update by YE2026, Phase 1/2 data in 1H 2027 ReDiscover preliminary data: doublet as of 01/13/2026, triplet as of 04/13/2026; ReInspire preliminary data as of 04/15/2026 ~$642M Cash as of end 1Q 2026 1. Clinical benchmark references: 2L breast cancer: capivasertib + fulvestrant (CDK4/6-experienced patient sub-population of CAPItello-291, Turner N Engl J Med 2023; 388:2058-2070) ; 1L breast cancer: CDK+ET in 2L+ (PACE Ph2: SABCS 2022 #GS3-06; postMONARCH Ph3: ASCO 2024 #1001; MAINTAIN Ph2: ASCO 2022 #LBA1004); atirmociclib Ph1: Pfizer R&D Oncology Day Feb 2024; vascular anomalies: alpelisib (EPIK-P2, Canaud 2024 Blood 144:5512) and KP-001 (Ozeki 2025, Orphanet Journal of Rare Diseases 20:64); 2. TAM calculated based on market benchmarks and internal analysis; 3. these benchmarks represent the earliest volumetric response evaluation timepoint; 4. Includes both confirmed and unconfirmed responses. After the data cut-off date, one 100mg BID patient that did not have a volumetric response as of the data cut-off date has converted to an unconfirmed response, resulting in a 100mg BID volumetric response rate of 43% (3/7), a volumetric response rate of 69% (9/13) for patients treated at 300mg BID or 100mg BID, and a volumetric response rate of 65% (13/20) across doses. None of the other response-evaluable patients’ response statuses have changed since the data cut-off date. VRR = Volumetric Response Rate. Note: These data are derived from different clinical trials at different points in time, with differences in molecule composition, trial design and patient populations. As a result, cross-trial comparisons cannot be made, and no head-to-head clinical trials have been conducted.
