Hypersensitivity Pneumonitis (HP) Clinical Trials

Hypersensitivity pneumonitis (HP), also called extrinsic allergic alveolitis, is an immune-mediated inflammatory lung disease caused by repeated inhalation and deposition of organic or inorganic antigens in the lungs, triggering complex Type III and IV hypersensitivity reactions. Common antigens include bird proteins (avian serum antigens in bird fancier's lung), mold spores (farmer's lung, bagassosis from moldy sugarcane), metal salts (metal worker's lung, beryllium disease), thermophilic actinomycetes, and isocyanates. Three clinical forms exist: acute (symptoms 4-6 hours after exposure with fever, chills, malaise resolving within days of avoidance), subacute (symptoms over days-weeks with continued exposure), and chronic (insidious development over months-years with progressive fibrosis).

The most common symptoms of Hypersensitivity Pneumonitis include Dyspnea and cough, Fever and chills within hours of exposure, Fatigue and malaise, Weight loss in chronic form, Progressive airflow obstruction, among others. Estimated 1 in 100,000 to 1 in 200,000 people, though likely underdiagnosed. Symptoms can range from mild to severe and may vary between individuals.

Trial Friend lists all active clinical trials for Hypersensitivity Pneumonitis from ClinicalTrials.gov, with eligibility criteria translated into plain English. Patients can filter by trial phase and recruitment status, search by location, and use the Match Me tool to score trials against their profile. Clinical trials are investigating immunomodulatory agents (immunosuppressants, novel biologics), antifibrotic therapies (pirfenidone, nintedanib), and molecular-targeted agents for progressive HP. Antigen identification and strict avoidance are critical for halting disease progression and preventing relapse.

As of September 2026, Trial Friend's curated drug index does not include an FDA-approved treatment specific to Hypersensitivity Pneumonitis. The Treatments section of this page checks FDA drug labels live and lists any approved drug whose label names the condition, and the trials listed below cover the investigational options.

Hypersensitivity Pneumonitis is an acquired condition, not an inherited one. An immune reaction to inhaled antigens (mold, bird proteins, chemicals); diagnosis depends on exposure history, imaging, and sometimes inhalation challenge, not gene testing. Estimated 1 in 100,000 to 1 in 200,000 people, though likely underdiagnosed.

Eligibility for Hypersensitivity Pneumonitis clinical trials depends on factors like age, diagnosis, treatment history, and overall health. Each trial sets its own inclusion and exclusion criteria. Trial Friend translates these requirements from medical language into plain English so patients can review them more easily. The Match Me tool can score your profile against active trials to help identify studies that may be a fit.

Participating in a Hypersensitivity Pneumonitis clinical trial typically involves scheduled visits, medical tests, and close monitoring by a research team. Depending on the study phase, you may receive an investigational treatment, a placebo, or the current standard of care. Trials may last from a few weeks to several years. Study participation is voluntary, and you can withdraw at any time.