Impact of Pre-transplant Anti-fibrotic Therapy for IPF Upon Lung Transplant Outcomes

Two oral medications, nintedanib and pirfenidone, were approved simultaneously by the FDA in October 2014 for the treatment of this disease. They are both considered anti-fibrotic agents and they each proved to slow the progression of disease in their respective clinical trials. Because of their anti-fibrotic properties, there have been concerns about the potential of these medications to impair wound healing following surgery. These concerns have led to variable approaches with respect to the management of the medications in patients listed for lung transplantation.

It is unknown whether continuing anti-fibrotic medications until the time of transplant increases the risks of intra-operative and post-transplant complications. Conversely, there are concerns that stopping the medications prematurely may promote a more rapid clinical decline in those awaiting transplantation and increase risk of death while on waiting lists. Whether there is a risk or benefit of continuing the medications during the pre-transplant period deserves investigation with the goal of establishing guidelines and best-practices. Once more is known about how best to manage anti-fibrotic therapy in the pre-transplant period, the question of whether these medications should be restarted following transplantation will also ultimately deserve exploration.

Idiopathic pulmonary fibrosis (IPF) is a terminal illness that typically develops in the sixth and seventh decades of life. It is a relentless fibrotic parenchymal lung disease that results in restrictive physiology and worsening symptoms of cough and shortness of breath. The median life expectancy from the time of diagnosis is in the 3-5 year range. The only therapy that has proven to extend life expectancy is lung transplantation.

There are 3 relevant, unanswered questions pertaining to the use of anti-fibrotic therapy for IPF around the time of lung transplantation:

1. Does stopping the medications prematurely while awaiting lung transplantation result in a greater risk of death due to acceleration of IPF?
2. Does continuing the medications until the time of transplant increase the risk of intra- and/or post-operative complications?
3. Is there a role for post-transplant anti-fibrotic therapy to reduce complications such as stenosis of the anastomosis, bronchiolitis obliterans syndrome and restrictive allograft syndrome, and/or to preserve native lung function following a single lung transplant?

The primary goal of this observational, pilot study is to collect retrospective data with the intention of using the findings to select primary outcomes and determine sample size for a sufficiently powered subsequent study.

The investigators will focus on the following aims:

Aim 1: Assess whether the time period between discontinuation of anti-fibrotic therapy for IPF and lung transplantation impacts (a) the risk of intra-operative and post-transplant complications and (b) short term survival.

Aim 2: Explore whether discontinuing anti-fibrotic therapy prior to lung transplantation is associated with increased risk of death while awaiting a transplant.

At the participating sites, all patients with IPF listed for lung transplantation who were being treated with one of the 2 anti-fibrotic therapies continuously for at least 90 days at the time of their eligibility for listing will be included. Outcomes include events that occurred after being listed and while waiting for lung transplantation, intra-operative and peri-operative events, and mortality data out to 6 months. Patients that underwent additional interventions (coronary artery bypass grafting, valve replacement) at the time of their transplant will be excluded.

Eligibility Criteria:
Inclusion Criteria:

1. Diagnosis of IPF
2. Taking one of the two anti-fibrotic therapies (nintedanib or pirfenidone) continuously for at least 90 days at the time of eligibility for listing
3. Listed for lung transplantation between July 1, 2015 and June 30, 2019

Exclusion Criteria:

1. Patients that underwent additional interventions (i.e. coronary artery bypass grafting, valve replacement) at the time of their lung transplant