Generic competition expected to be strong as many small-molecule drug brands face patent expirations

Small-molecule drugs in the United States will experience the greatest degree of brand erosion as patents of many of the most popular drugs expire during the next several years, leaving them exposed to generic competition, according to a report published by Datamonitor.

On average, sales will decline by 72% and volume will decline by 70% within 6 months of direct generic competition in the United States, the report said.

More than 80 blockbuster patents are set to expire through 2015. Pfizer will lose patent protection on 8 blockbuster products, including Lipitor (atorvastatin calcium), the best selling drug brand in the world, said Maura Musciacco, a healthcare analyst for Datamonitor. “Once Lipitor goes off patent, it will trigger incredible generic competition,” she told Drug Topics. “Many generic manufacturers will fight over getting a piece of the pie of this major drug.”

The report looked at patent expiration by country, therapy area, and setting. According to the report, brand erosion was greater in terms of speed and severity in the hospital setting, probably a reflection of greater patient loyalty in the retail setting. By therapy area, erosion of sales and volume was the greatest in the infectious disease, oncology, and cardiovascular categories.

Since the United States is considered the most mature of all generics markets (an estimated $59 billion in value), it is more susceptible to brand erosion than other countries, Musciacco said.

Following the United States, brand erosion will be most severe in the United Kingdom, Germany, and France. At the other end of the scale, brand erosion will be the lowest in Australia, Italy, Russia, Spain, and Japan.