Fibrosis treatment not ready for FDA’s OK
Dear Dr. Roach: I recently was diagnosed with pulmonary fibrosis. I am an otherwise healthy 73-year-old male who underwent bypass surgery seven years ago. I work out to keep in shape, not to look like a teenager. I had 12 weeks of pulmonary rehabilitation, which was very helpful.
I have found references to an enzyme, pirfenidone, which is said to dissolve the scar tissue. The enzyme is recognized in Europe and Canada as having value in the treatment of pulmonary fibrosis. The respective governments will pay for the enzyme treatments as part of their country’s medical program. I also am under the impression that our Food and Drug Administration has conducted two tests of this treatment and are now in a third.
Do you know of any reason not to take the enzyme, other than the lack of FDA approval? Do you think it is worth trying? Do you know where the current FDA test stands? When the scar tissue is dissolved, what is underneath the scar tissue?
For a retired person, the treatments are not cheap. But to increase my quality of life and that of my wife, I would gladly spend the money if I will do no damage to myself and there is a good possibility my condition can be improved.
Dear A.B.: Let’s start with whether the medicine might benefit you. Pulmonary fibrosis is a progressive inflammation and fibrosis of the lungs. The fibrosis reduces the ability of the lung to exchange oxygen and carbon dioxide, and symptoms usually are shortness of breath and cough.
Pirfenidone doesn’t actually dissolve the fibrosis (scar tissue); it prevents further damage. As such, it can’t reverse the disease — it can only slow down its course.
Studies have shown that although it does slow down the disease, it does not slow it down much. The biggest study showed that in one year without treatment, the effective lung volume decreased by 160 mL, and with pirfenidone, it decreased by 90 mL.
Although this is a benefit, it’s not a big difference, and it may not mean much in terms of improved symptoms and quality of life. It can cause rash and upset stomach severe enough that about 15 percent of people stopped taking it.
The FDA looks very carefully at the studies, often more carefully than agencies in other countries (it is always worth remembering that thalidomide was not approved in the U.S. and caused devastating birth defects in Europe).
I don’t second-guess the FDA, since it has more information than I do to guide its decisions. It may approve the medication.
In addition to the pulmonary rehabilitation you mention — and I am very supportive of it — there are other treatments that do improve symptoms, such as N-acetyl cysteine (in early disease) and sildenafil (with more advanced disease). Because of the modest benefit with this medication, its side effects and its costs, I would recommend against taking the medication before FDA approval.
Email questions to ToYourGoodHealth@med.cornell.edu.