By Jan Manarite, VP of Education and Advocacy
The answer is ‘no’ – not all clinical trials have a placebo.
Most Phase 1 and 2 trials DO NOT have a placebo, but most Phase 3 trials DO have a placebo group (arm). That being said, it is probably the first question you should ask if you are considering a clinical trial. ASK – don’t turn down a trial until you know the facts.
In addition, most placebo trials (usually the Phase 3) are now designed so that only 1/3 of patients receive placebo, therefore 2/3 of the patients receive the trial drug. Again, ASK – because all clinical trials are designed differently.
Most placebo trials are now designed so that 1/3 of patients receive placebo, but 2/3 receive the trial drug. ASK – because all clinical trials are different.
Finally, some clinical trials that have a placebo group, have a “crossover provision” written into the trial. This means that if a patient on placebo has disease progression, he is offered the option to “crossover” into the group that receives the trial drug or sometimes offered another drug.
One example of this is the Phase 3 trials years ago for PROVENGE (sipuleucel-T). In some of the trials, patients who received placebo were eventually offered PROVENGE if their prostate cancer progressed.
Another example is the current Phase 3 SPARTAN trial which has a crossover provision. The trial is for prostate cancer patients who have a rising PSA on hormone therapy, but no metastases. In this case, men who are on placebo, but have cancer progression are not offered the trial drug (ARN509), but they are offered free Zytiga (abiraterone).
So if you are considering a clinical trial, remember that they are all different. Develop some questions for the trial nurse or your physician based on your priorities and concerns. Simply put – ASK. And remember that most Phase 1 or Phase 2 clinical trials don’t have a placebo. If you are considering a Phase 3 trial, ask what percentage of patients receive placebo and ask if there is a crossover provision if you progress on placebo.
Better questions will get you better answers. Keep researching, and keep asking.