Gut-Targeted Vancomycin Boosts SBRT Survival in Early-Stage NSCLC

Vancomycin, a non-absorbed antibiotic that selectively depletes gram-positive gut bacteria, was paired with stereotactic body radiotherapy (SBRT) in a randomized pilot (NCT03546829) of medically inoperable stage I–II NSCLC (n=17; 9 vancomycin, 8 control). Given 125 mg PO QID for 5 weeks (starting one week pre-SBRT), the regimen reshaped microbiota/metabolome without any grade 3/4 toxicities. At ~3 years, vancomycin cut the risk of progression (HR 0.42, p = 0.049) and death (HR 0.38, p = 0.033) versus SBRT alone; historical SBRT alone cohorts report 5-year OS ≈64% and median PFS ≈62 months in this setting.