{"url_path":"/sec/rlay/8-k/2026-05-19/item-8-01","section_key":"item-8-01","section_title":"Item 8.01 Other Events.","topic":"sec","document":{"doc_type":"8-K","doc_date":"2026-05-19","source_url":"https://www.sec.gov/Archives/edgar/data/1812364/0001193125-26-229770-index.html","accession_number":"0001193125-26-229770","cik":"0001812364","ticker":"RLAY","issuer_name":"Relay Therapeutics, Inc.","edgar_url":"https://www.sec.gov/Archives/edgar/data/1812364/0001193125-26-229770-index.html","primary_entity_key":"0001812364","primary_entity_name":"Relay Therapeutics, Inc."},"word_count":1436,"has_tables":true,"body_markdown":"## Item 8.01 Other Events.\n\nOn 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.\n\n \n\nThe 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.\n\n \n\nUnless indicated otherwise, all data reported are as of the Data Cut-Off Date.\n\n \n\nInitial Efficacy Data\n\n \n\nOf 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.\n\n \n\nOf 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.\n\n \n\nFor the 20 response-evaluable patients:\n\n•\n60% of patients had a volumetric response with all responses coming at the first MRI;\n\no\nOf the 13 patients treated at 300mg BID or 100mg BID, 8 (62%) had a volumetric response;\n\no\nOf the 13 patients previously treated with alpelisib and/or sirolimus, 8 (62%) had a volumetric response;\n\no\nResponses were observed in patients with PROS and LM;\n\no\nResponses were observed across a spectrum of PIK3CA mutations;\n\n•\nFour responding patients had a 24-week scan, and all showed confirmation of response with deepening of reduction of lesion volume;\n\n•\n95% of patients experienced lesion reduction;\n\n•\nAfter 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; and\n\no\nNone of the other response-evaluable patients' response statuses have changed since the Data Cut-Off Date.\n\n \n\nInitial Patient and Clinician Reported Outcomes\n\n \n\nClinical 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.\n\n \n\nAt 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.\n\n \n\nThe 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.\n\n \n\nInitial Safety and Tolerability Data\n\n \n\nThe 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.\n\n \n\nAmong the 22 patients treated at 100mg and 300mg BID:\n\n•\nDose reductions were seen in 23% of patients, with no dose discontinuations;\n\no\nMedian dose intensity was greater than 99%;\n\n•\nOnly 2 patients (9%) experienced a Grade 3+ TRAE;\n\n•\nCommon adverse events associated with wild-type PI3Kα inhibition were low-grade, manageable, and reversible;\n\no\nNo rash or stomatitis of any grade was observed, and no grade 3 hyperglycemia or diarrhea was observed; and\n\n•\nNo prophylactic treatment was administered for management of any adverse event.\n\n \n\nThe 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.\n\n \n\nCautionary Note Regarding Forward-Looking Statements\n\n \n\nThis 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.\n\n \n\nAny 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."}