Antibiotic Use Dulls Immunotherapy Efficacy in Patients With Advanced Lung Cancer: Presented at ELCC

By Jenny Powers

GENEVA -- April 16, 2019 -- Antibiotic treatment received within the previous 2 months of
treatment with immunotherapy for advanced non-small-cell lung cancer (NSCLC) emerged as a risk factor for poorer outcome with PD-1 and PD-L1 inhibitors, researchers reported here at the 2019 European Lung Cancer Conference (ELCC).

Patients who received antibiotics prior to starting immunotherapy demonstrated significantly shorter median overall survival (10.6 months) compared with patients who did not receive antibiotics (29.9 months; P< .001).

“Antibiotics alter gut microbiota diversity and composition, and may affect anti-tumour immune responses following treatment with immune checkpoint inhibitors in NSCLC,” said Anne Schett, MD, University of Basel, Basel, Switzerland.

The researchers reviewed the clinical records of 218 patients with advanced NSCLC receiving treatment with immune checkpoint inhibitors and compared outcomes between patients who received antibiotics within 2 months prior to the start of immunotherapy and patients who did not.

“Antibiotic treatment is associated with a reduced clinical benefit from therapy with [immune checkpoint inhibitors],” said Dr. Schett. “The negative prognostic value of antibiotics was independent from known prognostic factors.”

Receipt of antibiotic treatment versus no antibiotic use significantly associated with an increased risk of progressive disease as best radiological response (73% vs 41%; P = .002).

“Further investigation is required on the mechanism behind this observation, with emphasis on the role of the gut microbiota composition in the context of anticancer immune response,” the authors concluded.

[Presentation title: Prognostic Impact of the Use of Antibiotics in Patients With Advanced Non-Small-Cell Lung Cancer (NSCLC) receiving PD-(L)1 Targeting Monoclonal Antibodies. Abstract 157P]

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