A major step forward for patients with scleroderma lung disease came with the publication of the SENSCIS trial (Oliver D, et al. N Engl J Med. 2019 Jun;380:2518-28 ). A total of 576 patients with scleroderma of recent onset (< 7 years) and at least 10% fibrosis on chest CT were randomized to receive either nintedanib or placebo. Patients were allowed to be supported by other therapies at stable doses prior to enrollment, and as such almost half of the patients were receiving mycophenolate. A significant improvement in annual FVC decline was reported in the treatment group, although the effect was tempered in the subgroup analysis when considering patients already on mycophenolate. Thus, the role of nintedanib in patients taking mycophenolate is less clear.
An ongoing study may clarify the role of mycophenolate and antifibrotic therapy in these patients. The phase 2 Scleroderma Lung Study III has a planned enrollment of 150 patients who are either treatment-naïve or only recently started on therapy (www.clinicaltrials.gov; NCT03221257). Patients are randomized to mycophenolate plus pirfenidone vs mycophenolate plus placebo, and the treatment phase will last 18 months. The primary outcome is change in baseline FVC. This trial design will hopefully answer whether the combination of an antifibrotic with an anti-inflammatory medication is superior to the anti-inflammatory therapy alone, in patients with at least some evidence of inflammation (ground-glass opacifications) on high-resolution CT scan (HRCT).
In ILD other than that associated with scleroderma, nintedanib was again explored in a large randomized controlled clinical trial. In INBUILD, 663 patients with progressive ILD not caused by IPF or scleroderma were randomized to nintedanib vs placebo for one year (Flaherty KR. N Engl J Med. 2019 Sep;381:1718-27 ). A majority of the patients (62%) had a UIP pattern on CT scan. There was overall improvement in the annual rate of decline in FVC in the treatment group, especially in the pr-determined subgroup of patients with a UIP pattern. The most common ILDs in the study were chronic hypersensitivity pneumonitis and that associated with connective tissue disease.
Pirfenidone is also being studied in multiple trials for various types of non-IPF ILD. Studies are either completed and nearing publication, or are ongoing. Some examples include the TRAIL1 study examining pirfenidone vs placebo in patients with rheumatoid arthritis (www.clinicaltrials.gov; NCT02808871), and the phase 2 RELIEF study that explores pirfenidone vs placebo in patients with progressive ILD from a variety of etiologies.
As more clinical trials are published, clinicians are now facing a different dilemma. Whereas the options for treatment were limited to only various anti-inflammatory medications in past years for patients with non-IPF ILDs, the growing body of literature supporting antifibrotics present a new therapeutic avenue to explore. Which patients should be started on anti-inflammatory medications, and which should start antifibrotics? Those questions may never be answered satisfactorily in clinical trials. Mycophenolate has become so entrenched in many treatment plans, enrollment into such a study comparing the two therapeutic classes head-to-head would be challenging.
However, a consideration of the specific phenotype of the patient’s ILD is a suggested approach that comes from clinical experience. Patients with more inflammatory changes on CT scan, such as more ground glass opacifications or a non-UIP pattern, might benefit from initiation of anti-inflammatory therapies such as a combination of corticosteroids and mycophenolate. Conversely, initiating antifibrotic therapy upfront, with or without concomitant mycophenolate, is a consideration if the pattern of disease is consistent with UIP on CT scan.