Study design challenges
Nonetheless, Dr. Khanna said the SLS-III data are consistent with the SLS-II findings, with mean improvements in FVC of 2.24% and 2.1%, respectively.
“The next study may be able to replicate what we tried to do, keeping in mind that there are really no MMF-naive patients who are walking around,” Dr. Khanna said. “So the challenge is about the feasibility of recruiting within a trial vs. trying to show a statistical difference between the drug and placebo.”
This study could serve as a foundation for future studies of MMF in patients with SSc-ILD, Robert Spiera, MD, of the Hospital for Special Surgery in New York, said in an interview. “There are lessons to be learned both from the study but also from prior studies looking at MMF use in the background in patients treated with other drugs in clinical trials,” he said.
Dr. Spiera noted that the study had other challenges besides the difficulty in recruiting patients who hadn’t been on MMF therapy. “A great challenge is that the benefit with regard to the impact on the lungs from MMF seems most prominent in the first 6 months to a year to even 2 years that somebody is on the drug,” he said.
The other challenge with this study is that a large proportion of patients had limited systemic disease and relatively lower levels of skin disease compared with other studies of patients on MMF, Dr. Spiera said.
“The optimal treatment of scleroderma-associated lung disease remains a very important and not-adequately met need,” he said. “Particularly, we’re looking for drugs that are tolerable in a patient population that are very prone to GI side effects in general. This study and others have taught us a lot about trial design, and I think more globally this will allow us to move this field forward.”
Dr. Khanna disclosed relationships with Actelion, Boehringer Ingelheim, Bristol-Myers Squibb, CSL Behring, Horizon Therapeutics USA, Janssen Global Services, Prometheus Biosciences, Mitsubishi Tanabe Pharma Corp., Genentech/Roche, Theraly, and Pfizer. Genentech provided funding for the study and pirfenidone and placebo drugs at no cost.
Dr. Spiera disclosed relationships with GlaxoSmithKline, Boehringer-Ingelheim, Corbus Pharmaceutical, InflaRx, AbbVie/Abbott, Sanofi, Novartis, Chemocentryx, Roche and Vera.