Hypersensitivity Pneumonitis - Market Share Analysis, Industry Trends & Statistics, Growth Forecasts (2026-2031)

The hypersensitivity pneumonitis market size was valued at USD 1.32 billion in 2025 and is estimated to grow from USD 1.39 billion in 2026 to reach USD 1.79 billion by 2031, at a CAGR of 5.25% during the forecast period (2026-2031). This report is Segmented by Disease Type (Acute, Subacute, Chronic), Diagnosis (Imaging, Lab Testing, Bronchoscopy/BAL, Biopsy), Therapy (Corticosteroids, Immunosuppressants, Antifibrotics, Supportive Care), Route (Oral, Injectable, Inhaled), End User (Hospitals, Specialty Clinics, Diag. Labs, Academic Institutes), and Geography (N. America, Europe, APAC, MEA, S. America). Forecasts in Value (USD).

Global Hypersensitivity Pneumonitis Market Trends and Insights

Fibrotic Hypersensitivity Pneumonitis Expands Long-Term Treatment Need

Fibrotic hypersensitivity pneumonitis is expanding long-term treatment need in the hypersensitivity pneumonitis market, as clinicians now manage it as a distinct disease course with a different prognosis and treatment pathway. Hypersensitivity pneumonitis represented 26% of the INBUILD population for progressive fibrosing interstitial lung disease, highlighting its significant treatment resource requirement within the broader care setting. In Japan’s two-year nintedanib post-marketing surveillance, hypersensitivity pneumonitis accounted for 10.05% of the PF-ILD cohort, and 73.17% of these patients experienced adverse drug reactions, indicating an active and closely monitored treatment group. Germany’s 2025 S2k guideline endorsed antifibrotic therapy for progressive fibrotic hypersensitivity pneumonitis and added structured workplace exposure surveillance, raising prescribing standards in that market and potentially influencing nearby European countries.

Progressive Fibrosing ILD Treatment Spillover Broadens the Hypersensitivity Pneumonitis Market

The hypersensitivity pneumonitis market is widening because drugs initially developed for idiopathic pulmonary fibrosis are now used under the broader progressive pulmonary fibrosis label, where hypersensitivity pneumonitis is an explicit underlying diagnosis. Boehringer Ingelheim’s nerandomilast received FDA approval in December 2025 for progressive pulmonary fibrosis, marking a major step for antifibrotic therapy in this treatment space. The FIBRONEER-ILD trial showed that nerandomilast 9 mg delivered an 83 mL advantage over placebo in FVC preservation at week 52, with a consistent treatment effect in the hypersensitivity pneumonitis subgroup. The same product received a positive CHMP opinion in May 2026 and UK MHRA approval in July 2026, creating a multi-region regulatory pathway within a single year. Each new progressive pulmonary fibrosis trial that includes hypersensitivity pneumonitis as a subgroup strengthens payer arguments and supports higher-value therapy adoption across the hypersensitivity pneumonitis market.

No Single Diagnostic Gold Standard Slows Treatment Initiation

The absence of a widely accepted diagnostic gold standard slows treatment initiation in the hypersensitivity pneumonitis market, as clinicians often reclassify patients across different diagnostic systems before finalizing care plans. The 2020 ATS, JRS, and ALAT criteria, the ACCP framework, and the 2025 Korean guideline differ in sensitivity and specificity, creating variation across centers, particularly in lower-resource settings. Clinicians often require bronchoscopy and bronchoalveolar lavage for high-confidence diagnosis, but these invasive procedures are not consistently available outside tertiary interstitial lung disease centers. Inconsistent serological testing, driven by non-standardized ELISA and chemiluminescence methods and geography-specific antigen panels, further extends referral timelines, delays specialist engagement, and slows movement into guideline-based treatment.

Other drivers and restraints analyzed in the detailed report include:

• High Diagnostic Uncertainty Sustains Multidisciplinary Decision-Making
• Occupational Surveillance in Farming and Bird-Related Settings
• Reimbursement Pressure Favors Low-Cost Steroid Regimens

Segment Analysis

Chronic hypersensitivity pneumonitis held 48.65% of the disease-type segment in 2025, giving it the leading position in the hypersensitivity pneumonitis market. Its lead came from longer care episodes and higher use of imaging, follow-up, antigen avoidance counseling, corticosteroids, immunosuppressants, and antifibrotics. Acute and subacute disease also remained important, as they continued to generate diagnostic work and monitored follow-up despite better reversibility than chronic fibrotic cases. A 2025 PLOS ONE study showed that home mold exposure was often missed outside Japan, indicating that some subacute and chronic cases were not identified until clinicians reviewed environmental history in more detail.

Acute hypersensitivity pneumonitis is projected to grow at a 6.93% CAGR through 2031, making it the fastest-expanding disease subtype in the hypersensitivity pneumonitis market. More structured occupational screening is identifying mild and moderate acute cases that were previously treated as viral illness or short-term respiratory irritation. A nationwide Japanese study found that humidifier lung, mainly acute and subacute in phenotype, showed a rising trend during 2011-2021, with a notable increase during the COVID-19 period as indoor time and humidifier use increased. Japan’s first national prevalence estimates for fibrotic and non-fibrotic hypersensitivity pneumonitis also gave the hypersensitivity pneumonitis market a stronger base for planning case volume and treatment demand in the region.

Imaging accounted for 57.23% of the hypersensitivity pneumonitis market size within diagnosis in 2025, making it the largest diagnostic segment. HRCT remained the first-line tool across major guidelines because it was central to separating fibrotic from non-fibrotic patterns and narrowing the differential diagnosis. A 2025 study in Diagnostics found that expiratory HRCT, especially air trapping assessment, was one of the strongest single radiologic signals supporting a multidisciplinary diagnosis of hypersensitivity pneumonitis. Bronchoscopy and bronchoalveolar lavage remained important when imaging was inconclusive, while lung biopsy remained limited to selected cases requiring granuloma identification.

Laboratory testing is forecast to grow at an 8.67% CAGR through 2031, making it the fastest-growing diagnostic sub-segment in the hypersensitivity pneumonitis market. Growth is being driven by serum-specific IgG panels, KL-6 testing, and broader proteomic approaches that support less invasive diagnosis. A 2025 Respiratory Research study reported that a combined exosomal KL-6, CAPN2, and SP-B model achieved an AUC of 0.987 in interstitial lung disease subtyping, setting a strong benchmark for future hypersensitivity pneumonitis-focused assays. A 2026 preprint also identified two blood-based immune-metabolic endotypes in fibrotic hypersensitivity pneumonitis with different clinical trajectories, suggesting that laboratory tools will move from broad screening toward more precise disease phenotyping in the hypersensitivity pneumonitis market.

Complete Report Scope:

• By Disease Type
  • Acute Hypersensitivity Pneumonitis
  • Subacute Hypersensitivity Pneumonitis
  • Chronic Hypersensitivity Pneumonitis
• By Diagnosis
  • Imaging
  • Laboratory Testing
  • Bronchoscopy and Bronchoalveolar Lavage
  • Lung Biopsy
• By Therapy
  • Corticosteroids
  • Immunosuppressants
  • Antifibrotics
  • Supportive Care
• By Route of Administration
  • Oral
  • Injectable
  • Inhaled
• By End User
  • Hospitals
  • Specialty Clinics
  • Diagnostic Laboratories
  • Academic and Research Institutes
• By Geography
  • North America
    • United States
    • Canada
    • Mexico
  • Europe
    • Germany
    • United Kingdom
    • France
    • Italy
    • Spain
    • Rest of Europe
  • Asia-Pacific
    • China
    • India
    • Japan
    • Australia
    • South Korea
    • Rest of Asia-Pacific
  • Middle East and Africa
    • GCC
    • South Africa
    • Rest of Middle East and Africa
  • South America
    • Brazil
    • Argentina
    • Rest of South America

Geography Analysis

North America held a 41.56% share in 2025, making it the largest regional block in the hypersensitivity pneumonitis market. The region benefited from strong interstitial lung disease infrastructure, high specialist access, and reimbursement pathways that supported advanced therapies more effectively than many public systems. The United States remained the largest national market in the region, with reported incidence ranging from 1.28 to 1.94 new cases per 100,000 persons annually. In addition, 50% of U.S. cases still had an unidentified antigen, supporting repeat referrals, imaging, and specialist reviews. Nerandomilast’s U.S. approval in December 2025 also positioned North America at the forefront of the antifibrotic shift in the hypersensitivity pneumonitis market.

Europe formed the second-largest regional cluster in the hypersensitivity pneumonitis market, led by Germany, the United Kingdom, and France. Germany’s S2k guideline in January 2025 formalized antifibrotic use in progressive fibrotic hypersensitivity pneumonitis and reinforced workplace exposure surveillance, which may influence prescribing standards across nearby countries. In the United Kingdom, MHRA approval for nerandomilast in July 2026 created a formal treatment path for idiopathic pulmonary fibrosis and progressive pulmonary fibrosis, including hypersensitivity pneumonitis-related fibrosis. Spain’s REGINHA registry also helped define local outcomes, supporting prescribing practice and later formulary negotiations.

Asia-Pacific is forecast to grow at a 9.56% CAGR through 2031, making it the fastest-growing geography in the hypersensitivity pneumonitis market. Japan remains a key driver, as its first national epidemiological survey estimated fibrotic hypersensitivity pneumonitis prevalence at 6.3 per 100,000 and non-fibrotic prevalence at 3.6 per 100,000, with notable southern clustering linked to mold and bird exposure. Japan’s 2026 post-marketing surveillance results also confirmed real-world nintedanib use in progressive fibrosing disease programs that included hypersensitivity pneumonitis. South Korea reported incidence rates of 1.14 to 2.16 per 100,000 persons between 2011 and 2020, and its 2025 guideline added conditional support for antifibrotics in fibrotic disease. The Middle East and Africa and South America will remain longer-term opportunities, as specialist access, reimbursement depth, and occupational monitoring remain uneven across many countries.

List of Companies Covered in this Report:

• Abbott Laboratories
• Abbvie
• Amgen
• AstraZeneca
• aTyr Pharma, Inc.
• Boehringer Ingelheim
• Bristol-Myers Squibb
• Eli Lilly and Company
• Roche
• Gilead Sciences
• Johnson & Johnson
• Merck
• Novartis
• Pfizer
• Sandoz Group AG
• Sanofi
• Siemens Healthineers
• Sun Pharmaceuticals Industries
• Sysmex
• Thermo Fisher Scientific

Additional Benefits:

• The market estimate (ME) sheet in Excel format
• 3 months of analyst support