Archive for December, 2010

It’s A Math, Math World (Clinical Trials)

Some of the information in this article (i.e. definitions) is from the book: Fundamentals of Clinical Trials (Friedman, Furberg, DeMets, 1998, 3rd edition)

Statistics has a huge part in the biopharma industry; especially in clinical trials. A clinical trial is a prospective study used to compare the effect(s) of an intervention(s) against a control in human subjects.  It is prospective rather than retrospective, meaning the subjects are followed forward in time and the data collected during the trial. Each subject must be followed forward from a well-defined point which is designated as time-zero or baseline. This time point may be different for every subject because subjects are recruited and may enter the study at different times.

A clinical trial must test an intervention(s) which is defined as “prophylactic, diagnostic or therapeutic agent, device, regime, procedure, etc.” that is tested in an attempt to alter some aspect of the participants (study subjects). There must also be a control group to which the intervention group is compared. At baseline, the control group must be as similar as possible to the active treatment group(s) such that any effect of the intervention(s) can be measured properly and attributed to the intervention.  Sometimes an investigational treatment is compared to the best intervention being used currently.  Other times, if there is no “best treatment”, a non-active, inert placebo treatment is used instead as a control.

In our future work, we will be considering the application of clinical trials to pharmaceutical research; the testing of investigational medications in humans. The clinical trials process is in 4 phases:

Phase 1: This is the first phase of human drug testing. In this phase, the drug is being tested in healthy human “volunteers” (note we do not call them patients because they are not sick) to study the safety, absorption, and tolerability of the drug. Also, the investigators try to determine a safe starting dose for future research studies. This phase involves a relatively small group of people.

Phase 2:  In this phase, the goals are to determine efficacy of the drug, whether the drug has beneficial biologic activity, and the rate of adverse events, or side effects. These trials usually occur in several hundred people who have the medical condition that the drug is intended to treat.

Phase 3: In this phase, the drug is tested against other drugs currently used therapeutically to treat the condition the patients have. These trials are conducted in several thousand people and occur just before the drug goes to the FDA for approval.

Phase 4: These trials are conducted after the drug is approved and is on the market. Sometimes, tests are done to check safety concerns or to test the drug to treat conditions it was not approved to treat. These are called off-label indications.

In future posts, I will exam other aspects of clinical trials and how statistics ties into them. We are done with the basic stats for now. We are diving into the applications to clinical research.

Like what you read? Get blogs delivered right to your inbox as I post them so you can start standing out in your job and career. There is not a better way to learn or review college level stats topics than by reading, It’s A Math, Math World 

Email Marketing You Can Trust