biostudies-literatureMonjazeb AMNCATS NIH HHSU.S. Department of Health & Human Services | NIH | National Cancer InstituteU.S. Department of DefenseNCI NIH HHSNIAMS NIH HHSNIH HHS5332https://www.ebi.ac.uk/biostudies/studies/S-EPMC10474145biostudies-literatureUnknown14(1)Stereotactic ablative radiotherapy (SABR) is a standard-of-care for medically-inoperable-early-stage non-small cell lung cancer (NSCLC). One third of patients progress and chemotherapy is rarely used in this population. We questioned if addition of the immune-checkpoint-inhibitor (ICI) atezolizumab to standard-of-care SABR can improve outcomes. We initiated a multi-institutional single-arm phase I study (NCT02599454) enrolling twenty patients with the primary endpoint of maximum tolerated dose (MTD); secondary endpoints of safety and efficacy; and exploratory mechanistic correlatives. Treatment is well tolerated and full dose atezolizumab (1200 mg) is the MTD. Efficacy signals include early responses (after 2 cycles of ICI, before initiation of SABR) in 17% of patients. Biomarkers of functNature communicationsAtezolizumab plus stereotactic ablative radiotherapy for medically inoperable patients with early-stage non-small cell lung cancer: a multi-institutional phase I trial.PMC10474145W81XWH-15-2-0063P30CA093373NIH/NCI R01 CA240751R00 CA2565264R00CA256526P30 CA093373S10 OD032406UL1 TR001863K24 AR077313R01 CA240751Merleev AAMirhadi ABeckett LVick LVMaverakis EMurphy WJMorris LALuxardi GRiess JWEastham DGarcia LSchalper KALi TMonjazeb AMLara FShiao SLDaly MEBorowsky ACanter RJKelly KMarusina AIChen SMcGee HMfalseAtezolizumab plus stereotactic ablative radiotherapy for medically inoperable patients with early-stage non-small cell lung cancer: a multi-institutional phase I trial.Stereotactic ablative radiotherapy (SABR) is a standard-of-care for medically-inoperable-early-stage non-small cell lung cancer (NSCLC). One third of patients progress and chemotherapy is rarely used in this population. We questioned if addition of the immune-checkpoint-inhibitor (ICI) atezolizumab to standard-of-care SABR can improve outcomes. We initiated a multi-institutional single-arm phase I study (NCT02599454) enrolling twenty patients with the primary endpoint of maximum tolerated dose (MTD); secondary endpoints of safety and efficacy; and exploratory mechanistic correlatives. Treatment is well tolerated and full dose atezolizumab (1200 mg) is the MTD. Efficacy signals include early responses (after 2 cycles of ICI, before initiation of SABR) in 17% of patients. Biomarkers of funct2023-01-01T00:00:00Z2023 Sep2026-07-14T19:57:07.393Z2025-02-19T01:18:01.146ZS-EPMC104741453765808310.1038/s41467-023-40813-w