Dear Dr. Roach: In these days of quickly rising drug costs, some companies lose their patents, allowing for generic versions, but others do not. I use a brand-name HFA inhaler for my COPD, and it should have gone off patent eight years ago. What change could possibly keep it under patent two times? — J.C.A.
Answer: All patents for drugs expire, but in order for a generic drug to be approved, it must pass stringent testing by the Food and Drug Administration. One commonly used combination inhaler, Advair, went off patent in 2010, but no generic was approved until 2019. Since brand-name Advair is expensive ($440 per inhaler, which lasts a month, at Goodrx.com), many patients were anxiously awaiting a generic alternative. It’s finally available (fluticasone/salmeterol) for about $115 an inhaler on GoodRx.
Manufacturers do sometimes change the drug slightly to extend their patents of their best-selling drugs. For many years the Prilosec brand of omeprazole was very expensive. Just before a generic became available, the manufacturer released a new drug, esomeprazole (Nexium). It is almost exactly the same drug.