Reverse engineering drugs is straightforward and relatively trivial. There is no correlation between ease of reverse engineering and R&D cost.
The very high cost comes from development of a drug candidate, not the initial discovery of a candidate. If you skip the part where they demonstrate that the chemical is effective, efficient, and safe for its intended purpose in large human populations then you are correct. At that point it is just a moderately low-cost chemical manufacturing problem.
However, I only see them copying drugs where someone else spent billions of dollars demonstrating safety and effectiveness. There are myriad drug candidates that no one has proven safe and effective that they are not copying because that would require real investment on their part.
Uhm, "Reverse engineering drugs is straightforward and relatively trivial". Any proof to backup your claim?
"spent billions of dollars demonstrating safety and effectiveness". Really? How much of the corporate koolaid have you drunk? Have you heard of Vioxx? Numerous other drugs being recalled. http://en.wikipedia.org/wiki/Rofecoxib Have you heard of how intertwined the FDA and lobbyists are? Sheesh.
Reverse engineering a drug is simple for a couple reasons. First, the compound is clearly described in the patent. Second, chemical analysis of so-called "small molecule" compounds is a basic skill every chemistry undergrad learns.
The most difficult part is probably designing the production synthesis process but even that is routine for people who do that kind of thing (chemical engineers).
The very high cost comes from development of a drug candidate, not the initial discovery of a candidate. If you skip the part where they demonstrate that the chemical is effective, efficient, and safe for its intended purpose in large human populations then you are correct. At that point it is just a moderately low-cost chemical manufacturing problem.
However, I only see them copying drugs where someone else spent billions of dollars demonstrating safety and effectiveness. There are myriad drug candidates that no one has proven safe and effective that they are not copying because that would require real investment on their part.