Table 4.

Summary of Immunosuppressive Therapies in SSc-ILD

Drug	Proposed Mechanism of Action	Status of Investigation
Cyclophosphamide	Alkylating agent that prevents cell division by cross-linking DNA strands and decreasing DNA synthesis	SLS I: multicenter, double-blinded placebo-controlled RCT FAST : multicenter, double-blinded placebo-controlled RCT
Mycophenolate mofetil	Exhibits a cytostatic effect on T and B lymphocytes through the inhibition of de novo guanosine nucleotide synthesis	SLS II: multicenter, double-blinded placebo-controlled RCT (ongoing)
Azathioprine	Imidazolyl derivative of mercaptopurine that incorporates its metabolites into replicating DNA and halts replication	Single unblinded RCT of 60 patients
Rituximab	Monoclonal antibody directed against the CD20 antigen on B lymphocytes	Small RCT of 14 patients Nested case-control designed study
Autologous	HSCT Administration of hematopoietic progenitor cells derived from the individual with the disorder to “reset” an autoreactive immune system	ASTIS: phase II, multicenter, event-free survival study SCOT: phase II/III, multi-center, eventfree survival study (ongoing) ASSIST: single-center, open-label phase II trial