pic thx to national eye institute on flickr creative commons

For many years, drug makers were criticized for racing to market with so-called me-too medicines. These are drugs that arrive in the marketplace after the first in a particular class of medicines is approved for treating a certain malady.

Instead of developing something that offers little, if any, improvement over a first-in-class drug – say, yet another high-cholesterol treatment- critics have contended that drug makers should use precious R&D resources to focus on developing therapies for ailments that are lacking treatments.

Now, though, a new analysis suggests the me-too phenomenon often occurred because companies were simply engaging in concurrent drug development, rather than opportunistic efforts to ride on the coattails of a successful medicine.

A review of approvals found that 83 percent of so-called later-in-class drugs were already in the middle stages of drug development when a first-in-class medicine was approved, according to the Tufts Center for the Study of Drug Development.

The nonprofit, which is funded in part by the pharmaceutical industry, examined 40 first-in-class medicines approved by the Food and Drug Administration between 1998 and 2011. The therapeutic classes with the highest shares of later-in-class drugs were oncology at 34 percent and cardiovascular at 19 percent.

The analysis also found that half of those later-in-class drugs made it to the marketplace in just over two years after the first-in-class drug. This tells us that development of these medicines began not long after the first-in-class drug, according to Joseph DiMasi, a research associate professor and director of economic analysis at the Tufts center.

“Often, the science leads them to development in a certain therapeutic area more or less at the same time and they end up racing to the marketplace,” he told us. “By the time drugs in the same class are already approved, it’s almost too late for a company to start development, because the economics wouldn’t generally be favorable.”

How so? A later-in-class drug essentially mimics a first-in-class drug, which in addition to competition from lower-cost generics, face patents that are closer to expiring. By the time this newer medicine wins FDA approval, it may effectively encounter the same effects of low-priced competitors. “The notion is that a company is less likely to pursue such a drug unless it had superior attributes,” said DiMasi.

As it turns out, the review found that nearly 78 percent of first-in-class drugs were given a priority review by the FDA. This means the agency determined the medicines, if approved, would constitute a significant improvement in safety or effectiveness when compared to existing therapies. But so did nearly 52 percent of the later-in-class medicines, according to the review.

“This speaks to the notion that the first-in-class is not necessarily the best in class,” DiMasi posited. “About half of the me-too drugs were thought to represent a significant therapeutic gain over existing therapies, including the first-in-class. And even if they didn’t, they should have introduced some competition into the marketplace in terms of pricing.”

Maybe so. Then again, the Tufts analysis also noted that about 90 percent of all later-in-class drugs had at least initiated Phase I, or early-stage, clinical testing abroad or in the US prior to FDA approval for the first-in-class drug. Such a lag time could be a distinct disadvantage. And one could certainly argue that pursuing development at this stage of the process does, indeed, reflect a desire to simply piggyback on the success of a first-in-class drug.