antifibrotic therapy

Antifibrotic therapy is medicine aimed at the scarring process itself, trying to slow the lung's relentless laying down of fibrous tissue. Rather than fighting inflammation, these drugs interfere with the signals that drive cells to produce excess collagen, in effect easing off the accelerator on scar formation.

Two oral drugs are central: pirfenidone and nintedanib. Nintedanib blocks several growth-factor receptors involved in fibrosis, while pirfenidone works through several less precisely defined antifibrotic and anti-inflammatory actions. Both have been shown in trials to slow the yearly decline in lung function, most clearly in idiopathic pulmonary fibrosis.

Their use has since broadened to other progressive fibrosing lung diseases, where fibrosis keeps advancing despite treatment of the underlying cause. The honest framing is that they slow progression rather than reverse or cure disease, and the benefit is measured in a gentler downhill slope, not improvement.

These medicines have real side effects. Pirfenidone commonly causes nausea, sun sensitivity, and rash, while nintedanib often causes diarrhoea and can affect the liver. Choosing and continuing antifibrotic therapy is a balance of benefit, tolerability, and the individual's goals, and is best managed in a specialist interstitial lung disease service.