In-Bedroom Air Filtration as Adjuvant Therapy in Cancer Survivors

27 Mar 20264 min read0 viewsINTERVENTIONAL Trial

GIST

Official title: A Series of N-of-1 Randomised, Adaptive, Blinded, Placebo-Controlled Trials of Overnight In-Bedroom Air Filtration as Adjuvant Treatment in Reducing Inflammatory Biomarkers Among Survivors of Adult-Onset Cancer With Elevated C-Reactive Protein Summary: The BREATHS trial aims to investigate whether overnight in-bedroom air filtration reduces inflammation and cardiac biomarkers in adult survivors of cancer who are at high risk for cardiovascular complications. The study consists of individualized experiments (N-of-1 trials) conducted in the home settings of adults residing in densely populated urban areas with the most severe air quality levels in Valencia, Spain, where fine particulate matter (PM2.5) and nitrogen dioxide levels exceed the limits set by the World Health Organization (WHO) and EU Directive. Participants will be exposed to 3 treatment sets (blinded phase), each consisting of a 14-day period of filtered air using a portable air filtration unit ("true-HyperHepa) and a 14-day period of unfiltered air (using the same portable unit with "sham filters").

Clinical Editorial

Study Design and Setting

The target population comprises adult cancer survivors at elevated cardiovascular risk, particularly in urban areas with poor air quality where PM2.5 and NO2 exceed WHO and EU limits.

The BREATHS trial uses a series of individualized N-of-1, adaptive, blinded, placebo-controlled experiments conducted in participants’ homes in Valencia, Spain.

Intervention and Comparison

Filtration is administered for at least seven consecutive hours per night, over a total duration of 4 to 12 weeks per participant.

The design thus includes blinded and potential unblinded segments to assess response.

Each participant experiences three treatment blocks, each comprising 14 days of nightly exposure to filtered air with a portable filtration unit (true-HyperHepa) and 14 days of unfiltered air using the same device fitted with sham filters.
If a participant shows no meaningful CRP reduction, an unblinded phase is added, consisting of 14 days without treatment, followed by 14 days with both nightly filtered and daily filtered air therapy.

Endpoints and Measurements

The primary endpoint is change in blood C-reactive protein (CRP) concentrations.
Secondary endpoints include changes in three other inflammatory and cardiovascular biomarkers measured in blood, plus blood pressure.
Both indoor and outdoor PM2.5 exposure levels will be continuously monitored throughout the study.

Rationale, Context, and Status

The study targets the intersection of cancer survivorship and cardiotoxicity by evaluating whether improving in-bedroom air quality can modulate inflammatory and cardiovascular biomarkers.
It is conducted in a real-world home setting within a high-pollution urban context, aiming to capture clinically relevant biomarker changes that could reflect systemic inflammatory status.
Enrollment is projected at about 10 participants, with recruiting ongoing and an estimated completion date in mid-2026.

Limitations and reporting notes

The design relies on short, repeated exposure blocks and biomarker changes over time, with the potential for carryover effects addressed by the N-of-1 framework and the planned unblinded phase for non-responders.
As a single-country, small-sample, individualized trial, findings may have limited generalizability and would require corroboration in larger cohorts and diverse environments.

Operational considerations

Continuous monitoring of both indoor and outdoor air pollutants is integral to contextualizing biomarker results.
The trial emphasizes objective inflammatory and cardiovascular biomarkers rather than solely clinical outcomes, aligning with the focus on subclinical inflammatory pathways in cardio-oncology.