Richard Channick - phaware® interview 519

Dr. Richard Channick, dives into the evolving world within pulmonary hypertension -- interstitial lung disease (PH-ILD). He sheds light on why early diagnosis matters and how new therapies are transforming care. Learn about the latest FDA-approved treatment and what’s on the horizon.

This Special Edition episode is sponsored by Gossamer Bio and Pulmovant.

Hello, I'm Rich Channick. I'm Professor of medicine at UCLA Medical Center and Co-Director of the Pulmonary Vascular Disease Program at UCLA. I've been there for the last six-and-a-half years, but have been involved with pulmonary hypertension for over 30 years from my fellowship in the '80s onwards. So, I've gotten to see all the evolution and changes that have occurred in this exciting field.

Today, I would like to talk about, really, an exciting, evolving area within pulmonary hypertension, which is pulmonary hypertension in the setting of interstitial lung disease or ILD, as we call it. The reason why this is exciting is that there actually are now emerging therapies for pulmonary hypertension due to ILD. The other important point to note is that this is actually more common than a lot of other forms of pulmonary hypertension.

So, what are we talking about here? What's the terminology? Well, ILD means interstitial lung disease, and very simply, it's scarring or fibrosis within the lungs. When we talk to our patients who have pulmonary arterial hypertension, we often say, "Your lungs are fine. It's the blood vessels running through your lungs where the problem is." Well, in ILD-PH, that's not the case. In ILD-PH, the lungs are not normal. There are a number of things that can cause this fibrosis or scarring of the lungs.

It can be due to some exposure. It can be due to another disease, like an autoimmune or connective tissue disease. It can be due to what we call idiopathic, or we don't know the cause for the pulmonary fibrosis. So, there's a lot of different causes. But what we do know is that in some patients, and maybe as many as 30% of patients, pulmonary hypertension or high blood-pressured lungs will develop as a result of the fibrosis.

Again, that distinguishes it from other forms of pulmonary hypertension, like PAH, where the lungs may be fine, or left-sided heart disease or pulmonary emboli. This is a distinct subgroup within pulmonary hypertension, also referred to as group three. So, that's how we define the problem.

What about treatment? This is, again, where the excitement is. Because there's now one FDA-approved therapy for ILD-PH, and then there are a number of others being looked at. There are some treatments for the ILD itself that are approved. Those treatments have variable effect, and there are some side effect issues.

We know that if the pulmonary hypertension develops with ILD, that needs to be treated, because the prognosis in patients who have ILD-PH is worse than if they didn't have PH. The ability to treat the PH in ILD, and to show a benefit will help patients, certainly from a point of view of quality of life and their exercise capacity, hopefully will improve outcomes.

Right now, in patients with ILD and ILD-PH, if it's severe enough, lung transplantation has historically been the only option, and that has its own problem. So, if one can find a treatment that can prevent or at least delay the need for lung transplantation, that's a big victory.

In addition to the FDA-approved therapy, which is inhaled treprostinil, it's a long-acting prostacyclin-type drug that's also used in PAH. But the inhaled form was shown to be beneficial in ILD-PH, and therefore it was FDA-approved for that. In addition, there are a number of other drugs that are going through the development, mainly in Phase-2 study; similarly to inhaled treprostinil, looking at the ability of these drugs to improve exercise capacity, improve the hemodynamics, and hopefully improve the outcomes.

The interest in ILD-PH has actually always been there, but it's always been a little bit of a head-scratcher. Because early on, there were some studies showing that some of the drugs we thought were exciting in PAH didn't necessarily help patients with ILD-PH. A couple examples actually were harmful. So, I think that slowed things down a little bit.

But in recent years, again, with some of these newer therapies, and maybe it has to do with the availability of inhaled therapies, because when you have a lung problem, like ILD, PH is an attraction to inhaling the treatment where it gets right to the lungs, and may not have effects outside the lungs. So that, I think, raised the interest even more.

Again, with inhaled treprostinil showing a benefit, a lot of the other newer agents, or small companies that have new molecules, became aware really that this is a big need for which there's not a lot of effective treatments. I guess that's a little in contrast, of course, to group one or PAH, where we now have essentially 15 approved therapies. So, certainly, again, I'm a physician, I'm not a business person. But from a strategic business point of view, looking at an area where there's only one approved treatment versus 15, you could see where that might lead.

The question is, how big is the pot? The pot may be bigger than we think of these ILD-PH patients, because one of the challenges is the recognition that a patient may be diagnosed with ILD or lung disease by an ILD specialist, but nobody's thinking about pulmonary hypertension. We believe, and we have some data to suggest, that may be underdiagnosed. So, the pot may actually be quite large of patients with ILD and pulmonary hypertension.

I think it's very important that patients obviously are their own advocates in everything, but certainly in this area. If a patient has interstitial lung disease or pulmonary fibrosis and is being managed by even a specialist in that, to at least raise the possibility that, could they also have pulmonary hypertension? And let their healthcare provider know that they're concerned about that.

Certainly, in the setting where, let's say, somebody's getting worse, so your symptoms are worsening, you're getting a little more short of breath, but the doctors are saying, "Well, your lungs are stable," the way we follow interstitial lung disease is a little different. We're getting pulmonary function tests, we may be getting imaging or CT scans of the chest. That may show stability of the lung disease, but yet the patient is feeling worse. That could be a sign or clue that pulmonary hypertension is developing.

Thank you very much for listening. My name is Dr. Richard Channick, and I'm aware that my patients are rare.

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