# Prospective Natural History Study of Smoking, Immune Cell Profiles, Epigenetics and COVID-19

> **NCT04403386** · — · COMPLETED · sponsor: **National Institute of Environmental Health Sciences (NIEHS)** · enrollment: 132 (actual)

## Conditions studied

- COVID-19

## Interventions

_None listed._

## Key facts

- **NCT ID:** NCT04403386
- **Lead sponsor:** National Institute of Environmental Health Sciences (NIEHS)
- **Sponsor class:** NIH
- **Phase:** —
- **Study type:** OBSERVATIONAL
- **Status:** COMPLETED
- **Start date:** 2020-06-01
- **Primary completion:** 2022-09-06
- **Final completion:** 2023-02-24
- **Target enrollment:** 132 (ACTUAL)
- **Last updated:** 2026-03-06


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT04403386

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT04403386, "Prospective Natural History Study of Smoking, Immune Cell Profiles, Epigenetics and COVID-19". Retrieved via AI Analytics 2026-06-05 from https://api.ai-analytics.org/clinical/NCT04403386. Licensed CC0.

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*[Clinical trials dataset](/datasets/clinical-trials) · CC0 1.0*