Antibiotic-exposed patients with non-small-cell lung cancer preserve efficacy outcomes following first-line chemo-immunotherapy.

BACKGROUND: Prior antibiotic therapy (pATB) is known to impair efficacy of single-agent immune checkpoint inhibitors (ICIs), potentially through the induction of gut dysbiosis. Whether ATB also affects outcomes to chemo-immunotherapy combinations is still unknown. PATIENTS AND METHODS: In this international multicentre study, we evaluated the association between pATB, concurrent ATB (cATB) and overall survival (OS), progression-free survival (PFS) and objective response rate (ORR) in patients with non-small-cell lung cancer (NSCLC) treated with first-line chemo-immunotherapy at eight referral institutions. RESULTS: Among 302 patients with stage IV NSCLC, 216 (71.5%) and 61 (20.2%) patients were former and current smokers, respectively. Programmed death-ligand 1 tumour expression in assessable patients (274, 90.7%) was ≥50% in 76 (25.2%), 1%-49% in 84 (27.9%) and <1% in 113 (37.5%). Multivariable analysis showed pATB-exposed patients to have similar OS {hazard ratio (HR) = 1.42 [95% confidence interval (CI): 0.91-2.22]; P = 0.1207} and PFS [HR = 1.12 (95% CI: 0.76-1.63); P = 0.5552], compared to unexposed patients, regardless of performance status. Similarly, no difference with respect to ORR was found across pATB exposure groups (42.6% versus 57.4%, P = 0.1794). No differential effect was found depending on pATB exposure duration (≥7 versus <7 days) and route of administration (intravenous versus oral). Similarly, cATB was not associated with OS [HR = 1.29 (95% CI: 0.91-1.84); P = 0.149] and PFS [HR = 1.20 (95% CI: 0.89-1.63); P = 0.222] when evaluated as time-varying covariate in multivariable analysis. CONCLUSIONS: In contrast to what has been reported in patients receiving single-agent ICIs, pATB does not impair clinical outcomes to first-line chemo-immunotherapy of patients with NSCLC. pATB status should integrate currently available clinico-pathologic factors for guiding first-line treatment decisions, whilst there should be no concern in offering cATB during chemo-immunotherapy when needed.

Reflection absorption infrared spectroscopy and temperature programmed desorption investigations of the interaction of methanol with a graphite surface.

Reflection absorption infrared spectroscopy (RAIRS) and temperature programmed desorption (TPD) have been used to investigate the adsorption of methanol (CH(3)OH) on the highly oriented pyrolytic graphite (HOPG) surface. RAIRS shows that CH(3)OH is physisorbed at all exposures and that crystalline CH(3)OH can be formed, provided that the surface temperature and coverage are high enough. It is not possible to distinguish CH(3)OH that is closely associated with the HOPG surface from CH(3)OH adsorbed in multilayers using RAIRS. In contrast, TPD data show three peaks for the desorption of CH(3)OH. Initial adsorption leads to the observation of a peak assigned to the desorption of a monolayer. Subsequent adsorption leads to the formation of multilayers on the surface and two TPD peaks are observed which can be assigned to the desorption of multilayer CH(3)OH. The first of these shows a fractional order desorption, assigned to the presence of hydrogen bonding in the overlayer. The higher temperature multilayer desorption peak is only observed following very high exposures of CH(3)OH to the surface and can be assigned to the desorption of crystalline CH(3)OH.