Mesothelioma is a relatively rare form of cancer linked to chronic asbestos exposure. There has been a sharp decline in asbestos exposure since the 1970s when asbestos use was halted for most applications. However, the incubation period for mesothelioma from initial exposure to asbestos to the onset of the disease varies from 20 to 50 years. As such, deaths related to this disease have risen recently and are expected to continue rising until the year 2020. This anticipated increase in incidence of mesothelioma has spurred considerable interest in clinical trials to develop better treatments for the deadly disease.
Until recently, clinical trials for mesothelioma were difficult to conduct. The disease had a rapid onset and progression, leading to a relatively short survival period in which to conduct clinical trials. Also, there was a lack of basic understanding about the clinical biology of the disease and how the disease changed during progression.
Specific clinical measures were difficult to obtain in order to demonstrate the response to treatment. Recently, as part of the Alimta clinical trial, researchers developed new metrics that included factors other than just pleural thickening or abnormal breathing capability. A number of new clinical trials are now underway, many of them using these new measurement techniques. Hopefully these trials will lead to ways to stop or reverse the progression of mesothelioma.
Clinical trials for evaluating mesothelioma treatments are broken into four parts or phases. These Phases are described below (Source FDA).
Researchers evaluate a drug or treatment in a small group of people/patients (20 to 80) for the first time to evaluate a drug's safety, determine the appropriate dosage range and identify side effects.
Researchers treat a larger group of people/patients to determine if the drug treatment is effective and safe for the dosage levels determined in Phase I.
Researchers administer the drug or treatment to a large group of people/patients to confirm the effectiveness of the drug and evaluate the drug's side effects. In this phase, the drug under evaluation will be compared to commonly used treatments. Additionally, researchers use Phase III trials to determine the proper protocol for the use of the drug when it is released for routine treatment.
Researchers perform follow-up studies from Phase III, primarily to obtain information that can be used when marketing the drug, such as drug risks, benefits and optimum use.
[Page updated March 2006]