Quantitative CT Measures Predict Progression and Detect Nintedanib Effects in INBUILD Substudy

A substudy of the double-blind, randomized, placebo-controlled INBUILD trial assessed quantitative computed tomography (QCT) in 474 patients with progressive pulmonary fibrosis. Investigators evaluated UCLA quantitative interstitial lung disease (QILD) and lung fibrosis scores, alongside Brainomix e-Lung total disease extent (TDE), reticulovascular score, and weighted reticulovascular score. Analyses examined associations with disease progression and imaging responses to nintedanib.

In placebo recipients, higher baseline QCT scores were associated with faster forced vital capacity (FVC) decline over 52 weeks. Scores above versus below the median were associated with greater risk of a decline in FVC percent predicted of at least 10% or death; differences in restricted mean survival time ranged from 40 to 65 days. At week 24, relative differences versus placebo in changes in QILD and e-Lung TDE were −7% (95% CI, −11 to −2; P=0.005) and −8% (95% CI, −12 to −4; P<0.001), respectively. At week 52, both differences were −7% (95% CI, −12 to −2; P<0.05).

These findings support QCT as a potential tool for predicting progression and assessing treatment effects in clinical trials. However, the imaging measures are structural endpoints, and these results do not establish their use as replacements for clinical outcomes. Only the abstract was available, limiting assessment of methods and generalizability.