Related recent news releasesThe ALS Association sponsors many clinical trials. Other ALS trials are funded through other organizations. For a list of current clinical trails see http://www.alsconsortium.org/search.php and the NIH clinical trials at http://clinicaltrials.gov/.
Overview SummaryClinical trials carry out tests on people to see whether a candidate therapy is safe and works to counter the effects of a disease. Before human patients are the subjects, therapy is tested in cells or tissue grown in the lab, and then in animals, to provide the best possible assurance that a drug will be safe for people to take.
A pilot trial is a very first look at a candidate therapeutic in people. Phase I testing looks at the safety of a candidate treatment, often in twenty or fewer people. Participants are examined for any adverse reactions or side effects. If any appear that are judged to be too dangerous, testing is halted and the drug will not advance any further in the clinical trials process.
Phase II testing attempts to determine the optimal dose, route (by mouth, by injection) and timing of doses of the candidate treatment. Information about a drug’s ability to help in the disease may be obtained in the course of Phase II testing, but such findings are not able to reliably predict a candidate’s effect. Usually less than a hundred patients are involved.
The therapeutic effect of the candidate is specifically sought in Phase III testing. This is the stage of testing that enrolls enough patients to allow a statistical judgment that a treatment is effective. Phase III trials usually require hundreds to thousands of participants.
Due to requirements for producing reliable data, patients may have to be of a certain age, gender, stage of disease, or even race, to participate. For ALS, restrictions are often looser to participate in clinical trials than for other conditions that are not so devastating or rapidly fatal. Nevertheless, ALS patients in clinical trials are required to fulfill certain criteria of the disease or disease severity (“Inclusion criteria”), and might be ineligible if they show certain other characteristics (“Exclusion criteria”).
Clinical trials can only test relatively few patients, and must make predictions from a few people that will most likely hold for the patient population as a whole. Statistics provide the means to judge if a change induced by drug treatment is likely to be a real, reproducible change, and that what doctors see in a restricted set of patients is likely to hold true for the entire population of patients with that disease.
The placebo effect is well known in medicine as a temporary improvement in pain or other symptoms of a disease that follows a fake pill. It is a real effect. But it is not due to the active properties of a drug. So testing of any new treatment must insure that the effect is due to the drug and not to the power of positive thinking, or to the extra attention from the medical staff that comes with participation in a clinical trial.
Fluctuations in disease progression are documented for many illnesses including ALS. Simple hope that a new treatment will work can color expectations and perceptions. A patient’s speech can appear clearer. A patient can gather strength to sit up unassisted or take a few steps unaided. Decline in abilities can slow or plateau. These are real effects of positive thinking. A control group helps to balance effects of the mind against effects of a drug.
A benefit to participating in a clinical trial is that the questions answered can benefit all patients with the disease. Even if a candidate treatment fails to hold promise, the results of any clinical trial give new insight and direction to those working to solve the disorder.