Measures of IPF Therapy Effectiveness Should Include Patients’ Views of Success, Researchers Argue

Clinical trials of idiopathic pulmonary fibrosis (IPF) therapies should include measures that reflect patients’ views of the success of treatments, Columbia University Medical Center researchers contend.

In particular, the trials should add reduction in respiratory-related hospitalizations to their measurement tool kit, the team said.

Patients’ views of treatment success could influence doctor and patient decisions about using therapies and could help experts draw up treatment guidelines, the researchers said in an opinion piece in the American Journal of Respiratory and Critical Care Medicine.

The team used insight they gained from a study about the IPF therapy Esbriet (pirfenidone) to write the article. The study showed that Esbriet lowered respiratory-related IPF hospitalizations.

Esbriet, developed by Genentech, is a U.S. Federal Administration-approved treatment for IPF.

The article argued that patients see fewer respiratory-related hospitalizations as an important treatment outcome because a decrease in visits is tangible, compared with therapy-related improvement in a lung function measure such as forced vital capacity, or FVC. The article was titled “Patient-Centered Outcomes in Idiopathic Pulmonary Fibrosis Clinical Trials,”

Doctors have long used improvements in FVC as their main measure of a treatment’s effectiveness because reduced lung function is an important predictor of death in patients with lung fibrosis, or scarring. Patients may not perceive it as a key measure, however.

An earlier study showed that only 7 percent of IPF patients on Esbriet have to be hospitalized for respiratory problems, versus 11 percent of patients on a placebo. The study, which included data from three Phase 3 clinical trials, also reported that Esbriet lowered the risk of death after hospitalization at one year, although not in the long run.

Another study, which Genetech presented at the American Thoracic Society International Conference in Washington, May 19-24, showed that Esbriet lowered deaths from all causes by 72 percent, compared with a  placebo.

Physicians can easily convey this kind of information to patients, and it is likely to influence shared treatment decisions, researchers argued. In addition, it could influence development of treatment guidelines and medical care reimbursements. That’s because it is cheaper to provide care for patients outside a hospital.

The number of hospitalizations has several benefits over FVC as a clinical trial measurement, the Columbia researchers contended. Respiratory-related hospitalizations can be measured if a patient becomes too sick to make a return visit, has a lung transplantation before a trial is over, or dies.

Using hospitalizations as a clinical trials measure would not require more patients to be included in the trials, the researchers added.

Although currently planned trials are likely to continue using FVC as a primary outcome measure, the trials could include analyses of respiratory hospitalizations to confirm the usefulness of the measure, the team said. This could influence the design of future trials, they said.