By Richard Lenti

In a blow to consumers and several manufactures of generic drugs, the U.S. Patent Office has extended Pfizer’s patent on Celebrex, the multi-billion dollar pain drug for treating rheumatoid arthritis and osteoarthritis.

The extension gives Pfizer (NYSE:PFE) another year and a half of selling a drug that has annual sales of more than $1.7 billion in the U.S. and nearly $3 billion worldwide. It also means cheaper generic versions of celecoxib, which is sold under the Celebrex brand name, may not be available to consumers until the end of 2015.

Read more at National Pain Report.