METHODS: We performed a comprehensive search in several databases published until April 2022. Studies were included if they were cost-effectiveness analyses reporting cost per quality-adjusted life-year or life-year on any biologic therapies as an add-on treatment for moderate to severe asthma in patients of all ages. Various monetary units were converted to purchasing power parity, adjusted to 2021 US dollars. The INBs were pooled across studies using a random-effects model, stratified by country income level (high-income countries (HICs) and low- and middle-income countries (LMICs)) and perspectives (health care or payer perspective (HCPP) and societal perspective (SP)) and age group (>12 years and 6-11 years). Heterogeneity was assessed using the I2 statistic.

RESULTS: A total of 32 comparisons from 25 studies were included. Pooled INB indicated that the use of omalizumab as an add-on treatment to standard therapy in those aged >12 years was not cost-effective in HICs from the HCPP (n = 8, INB, -6,341 (95% CI, -$25,000 to $12,210), I2=86.18%) and SP (n = 5, -$14,000 (-$170,000 to $140,000), I2=75.64%). A similar finding was observed in those aged 6-11 years from the HCPP in LMICs (n = 2, -$45,000 (-$73,000 to $17,000), I2=00.00%). Subgroup analyses provided no explanations of the potential sources of heterogeneity.