North America retains the largest revenue share (≈42%) through 2025, propelled by high biologic uptake and favorable reimbursement; however, Asia-Pacific is the fastest-expanding region, posting >8% CAGR on rising pollution-linked prevalence, expanding healthcare access, and accelerating adoption of low-cost generics. Competitive dynamics are intensifying as originators defend patent cliffs with device-plus-drug lifecycle extensions, while regional players leverage cost-efficient biosimilar monoclonal antibodies. Supply-chain resilience is under scrutiny post-pandemic, prompting dual-sourcing of APIs for inhaled corticosteroids and on-shoring of biologic fill-finish capacity. Collectively, these forces position the asthma treatment drugs market size for sustained, innovation-led expansion despite pricing headwinds and increasing environmental, social, and governance (ESG) compliance costs.