The National Library of Medicine has an interactive
Clinical Trials Tutorial. The text is also available as a
PDF file (100K).
It's one of the links on their
Clinicial Trials information page.
At
clinicaltrials.gov you can search for clinical trials by disease or by keywords, and you can use the following links for the trials listed under the main disease categories:
Aplastic anemia trials
MDS trials
PNH trials
You can also view the list of
other blood diseases for which there may be clinical trials.