Thank you for submitting this work regarding patterns of prescriptions of anti-fibrotic agents. I have a some comments and questions trying to have a better understanding of your study:
- Is there any data on what dosages of these medications were used? dosage change prior to discontinuation? and patients changing from Nintedanib to Perfinidone and vice versa? If the answer to all or some of these questions are no, then the authors need to state that clearly as a limitation of the study.
- Page 15 last paragraph, length of stay fig 4A and 4B is too short compared to reality (less than one day), do the authors have an explanation? Were there common diagnosis codes associated with such hospitalizations?
- Page 16 lines 15-20, do costs include blood testing for liver function tests? It would be informative to elaborate that, and also follow up PFTs?
- Page 16, line 42, why say prescription rate is very low? In real world, many IPF patients either do not need anti-fibrotic (very mild disease) or it is too late to prescribe (advanced disease when the benefit is no longer significant) or concern about side effects (patient is already thin, patient already has GI problems, etc). IPF pharmacotherapy decisions differ compared to cancer, infection and other diseases where we try to treat every possible patient. I suggest authors rephrase the point to reflect that it is a small portion of patients being prescribed the medications but that is not a (bad thing).
- Data from reference 20 is of a much smaller populations in the registry which might've been more selective. Where ref. 20 is cited, the authors can clarify that.

Thank you for your responses and clarifications as well as the edits you made to the body of the manuscript to address those points. For page 13, last paragraph, which was the second question in my reviews regarding patients average length of stay, I would suggest clarifying this paragraph that some of the patients were outpatients and that is what resulted in the mean of stays being less than 1 day. If the authors can rephrase the paragraph in a way that does not make the reader wonder how most patients were (admitted) for less than one day in the hospital.

Thank you for addressing and clarifying the review questions and comments.