The overall decrease in inflation-adjusted 28-day launch price from the first-of-kind to the final launch of a follow-on varied between -£2.00 (selective cyclo-oxygenase-2 inhibitors for rheumatoid arthritis) to -£259.99 (TNF-α inhibitors for rheumatoid arthritis), and in relative terms varied between −6.6% (selective cyclo-oxygenase-2 inhibitors for rheumatoid arthritis) to −83.9% (ACE inhibitors for hypertension). The gene discussed is TNF; the disease is rheumatoid arthritis.