Drug development is a process which takes a drug from initial discovery to the pharmacy shelves. Very few pharmaceutical products actually make it all the way through drug development, and sometimes the process can be an extremely costly and frustrating failure. Drug companies and scientific researchers persist with drug development and research because they are interested in finding new and potentially useful drugs, and because the steady release of new drugs is usually the cornerstone of profits.
The stages of drug development begin with the identification of a compound which may have a therapeutic use. This compound could come from a natural source, a random discovery in a lab, or a targeted effort to develop a compound which addresses a particular issue. Once this compound has been identified, tests can be used to determine its precise chemical makeup, and to learn how effective it is, and what it could be used for.
If the pharmaceutical company believes at this stage of the drug development process that it may have a useful compound, it can start to file paperwork with regulatory agencies, identifying and naming the compound so that the agencies can start reviewing it. At the same time, a lengthy series of tests and trials begins, typically starting in the lab, moving to animals, and eventually being expanded to humans in carefully monitored clinical trials. The results of these tests must all be supplied to the regulatory agency as part of the drug's application for approval.
At every stage of the drug development process, several concerns must be addressed. The first is safety: a compound is useless if it is extremely toxic, for example, or if it has severe side effects which can be detrimental to human health. Efficacy is also important, as drug companies want to make drugs which will actually work, ideally in new and innovative ways. The conditions which the drug can be used to treat may also be a cause of concern, as some avenues of exploration are more likely to generate profitable returns than others. Allergy medications, for example, generate more of a return on investment than drugs which treat tuberculosis.
If the drug makes it through early design and testing and it is approved by a regulatory agency, the company can present it for sale. Packaging for sale usually includes the determination of correct dosages, and the formulation of a drug in a form which will be easy to administer accurately. The pharmaceutical company must also develop packaging which discloses known side effects, risks, and adverse drug interactions.