Under Pressure: An Update on Pulmonary Hypertension

In the final portion of the talk, Dr. Gomberg-Maitland discussed new concepts in clinical trial design and endpoints, as well as new delivery methods for therapeutics and new targets for therapy. Although early trials in PH were single agent, placebo controlled, short in duration and focused on changes in measures of exercise capacity, more recent trials on PAH have become larger and longer in duration, and use background therapy and upfront combination therapy. Moreover, event-driven studies that have looked at sequential combination therapy effects on clinical worsening have encouraged development of more clinically relevant, novel, efficacy endpoints.

An example of a trial that challenged the existing paradigm was the drug macitentan (i.e., an endothelin receptor antagonist), which showed a significant reduction in the risk of clinical worsening (as measured by a primary composite endpoint of morbidity and mortality) that was not reflected by the change in the six-minute walk test, which had long been the most frequently used endpoint in PH trials.¹²

With respect to new ways to deliver treatment, Dr. Gomberg-Maitland discussed SynchroMed II pump and catheter system, an implantable system used for the direct intravascular delivery of treprostinil to the circulatory system.¹³

In Sum
This talk represented a thorough and thought-provoking update on the subject of pulmonary hypertension and, in highlighting past, present and future directions in this field, Dr. Gomberg-Maitland allowed the audience to much better appreciate the landscape of this important condition.

Jason Liebowitz, MD, completed his fellowship in rheumatology at Johns Hopkins University, Baltimore, where he also earned his medical degree. He is currently in practice with Skylands Medical Group, N.J.

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