# Fecal microbiota transplant overcomes resistance to anti-PD-1 therapy in melanoma patients

Source: https://onco.cc/key-papers/paper-davar-science/  
OnCo record `paper-davar-science` (Key paper). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Paper cited by one trial page, one technology page, one pathway page and one idea page, indexed on Europe PMC as PubMed record 33542131 and published in Science; the citing pages link this DOI, which is how the record was matched.

## Summary

Anti-programmed cell death protein 1 (PD-1) therapy provides long-term clinical benefits to patients with advanced melanoma. The composition of the gut microbiota correlates with anti-PD-1 efficacy in preclinical models and cancer patients. To investigate whether resistance to anti-PD-1 can be overcome by changing the gut microbiota, this clinical trial evaluated the safety and efficacy of responder-derived fecal microbiota transplantation (FMT) together with anti-PD-1 in patients with PD-1-refractory melanoma. This combination was well tolerated, provided clinical benefit in 6 of 15 patients, and induced rapid and durable microbiota perturbation. Responders exhibited increased abundance of taxa that were previously shown to be associated with response to anti-PD-1, increased CD8 + T cell activation, and decreased frequency of interleukin-8-expressing myeloid cells. Responders had distinct proteomic and metabolomic signatures, and transkingdom network analyses confirmed that the gut microbiome regulated these changes. Collectively, our findings show that FMT and anti-PD-1 changed the gut microbiome and reprogrammed the tumor microenvironment to overcome resistance to anti-PD-1 in a subset of PD-1 advanced melanoma.

Indexed on Europe PMC as PubMed record 33542131 (DOI 10.1126/science.abf3363). Matched by DOI alone: one trial page, one technology page, one pathway page and one idea page cite this DOI among their external links (the pages are listed under Related), and this page was written so that the citation resolves inside OnCo. No figure has been checked by an editor.

## Fields

- Kind: Key paper
- Last checked: 2026-09-22
- Tags: europepmc-ingest
- Journal: Science
- Year: 2021
- DOI: 10.1126/science.abf3363
- Authors: Davar D, Dzutsev AK, McCulloch JA, et al.
- What it means: One trial page, one technology page, one pathway page and one idea page on OnCo cite this paper by its DOI; this record gives the citation a page of its own so a reader can follow it without leaving OnCo. Read the abstract above alongside the citing pages listed under Related; the record was created automatically from the Europe PMC entry and its figures have not been checked by hand.
- Caveats: Matched to the citing OnCo records by DOI alone; the summary reproduces the Europe PMC abstract and no figure has been verified against the full paper.

## Sources

- Science 2021: https://doi.org/10.1126/science.abf3363
- PubMed: https://pubmed.ncbi.nlm.nih.gov/33542131/
- Europe PMC: https://europepmc.org/article/MED/33542131

## Connected records

- technologies: [Faecal microbiota transplantation for PD-1 non-responders](https://onco.cc/technologies/fmt-checkpoint-nonresponders/)
- pathways: [Microbiome-tumour interactions](https://onco.cc/pathways/microbiome-tumour/)
- ideas: [Microbiome transplant as a routine immunotherapy adjunct](https://onco.cc/ideas/idea-microbiome-io-fmt/)
- trials: [FMT plus pembrolizumab in anti-PD-1-refractory melanoma (Pittsburgh)](https://onco.cc/trials/fmt-pd1-refractory-melanoma-pitt/)
- journals: [Science](https://onco.cc/journals/science/)

---
JSON: https://onco.cc/api/v1/entities/paper-davar-science.json