ABSTRACT
Between 2000 and 2007, more than 2000 patients with pulmonary arterial hypertension (PAH) were enrolled in placebo-controlled trials. At the time of writing, most of these trials have been published and seven therapies are now licensed for PAH. This is remarkable success by any medical standard and has led, in turn, to many more trials of new therapies, combinations of therapies, and therapies given at time points earlier in the course of the disease, but, rightly, there is concern that these trials are well designed and use end points that reflect adequately the success or failure of the new approaches. Given the interest in the treatment of PAH, it is appropriate to consider the design of trials of new therapies or combinations of therapy for PAH and also to consider the end points that will be measured when trying to decide whether a drug or combination of drugs is effective or not. Treatments for PAH are always expensive, sometimes invasive and carry significant side effects. In order to convince patients, treating physicians, funding agencies, and regulatory bodies of the value of treatments it is, therefore, extremely important to conduct trials of appropriate design using end points of appropriate quality.
