Is cyclophosphamide still the gold standard in early severe rapidly progressive systemic sclerosis?

Cyclophosphamide (CYC) has been a gold standard of treatment for severe progressive Systemic Sclerosis (SSc), especially in patients with concomitant interstitial lung disease (ILD). This approach was based on results of several interventional studies, including randomized control trials, which mainly addressed SSc-ILD as a primary end point and skin involvement as a second one. The use of CYC is time-limited due to significant adverse events. More recently, other immunosuppressive and biological agents showed efficacy but better safety profile in patients with SSc and SSc-ILD. With regards to other end-points, post-hoc analyses, systematic reviews and metalysis showed that CYC had limited influence on patients' quality of life, event-free survival and mortality. Comprehensive patient's stratification according to a molecular, cellular and phenotypic pattern may help in choosing of personalized medicine with more ambitious treatment effect and should be the future direction. According to the above available data and even if scientific evidence may be missing, experts' opinion has changed the attitude to CYC as an anchor drug in the management of severe SSc. Indeed, CYC has been pushed to the second and even third treatment option after mycophenolate mofetil, tocilizumab or rituximab. This position became obvious during debate on this topic at CORA meeting 2023.