A good deal has been written lately about the "attrition rates" of new drug discoveries. A growing number of promising new leads ultimately prove to be too insoluble or unstable to be formulated. This problem is evident in the declining rate of new drug approvals. Fewer drugs and biologicals make it from Phase I to the marketplace, and half of Phase I drugs are likely to fail late in Phase III, according to FDA. The paper depicts that many pharmaceutical companies now conduct biological research studies to determine a compound's therapeutic potential.