Clinical trial protocol: PRednisolone in early diffuse cutaneous Systemic Sclerosis (PRedSS)

A Phase II randomized controlled trial of oral prednisolone in early diffuse cutaneous systemic sclerosis (PRedSS)

OBJECTIVES

Although the painful and disabling features of early diffuse cutaneous SSc (dcSSc) have an inflammatory basis and could respond to corticosteroids, corticosteroids are a risk factor for scleroderma renal crisis. Whether or not they should be prescribed is therefore highly contentious. Our aim was to examine safety and efficacy of moderate-dose prednisolone in early dcSSc.

METHODS

PRedSS set out as a Phase II, multicentre, double-blind randomized controlled trial, converted to open-label during the Covid-19 pandemic. Patients were randomized to receive either prednisolone (∼0.3 mg/kg) or matching placebo (or no treatment during open-label) for 6 months. Co-primary endpoints were the HAQ Disability Index (HAQ-DI) and modified Rodnan skin score (mRSS) at 3 months. Over 20 secondary endpoints included patient reported outcome measures reflecting pain, itch, fatigue, anxiety and depression, and helplessness. Target recruitment was 72 patients.

RESULTS

Thirty-five patients were randomized (17 prednisolone, 18 placebo/control). The adjusted mean difference between treatment groups at 3 months in HAQ-DI score was -0.10 (97.5% CI: -0.29, 0.10), P = 0.254, and in mRSS -3.90 (97.5% CI: -8.83, 1.03), P = 0.070, both favouring prednisolone but not significantly. Patients in the prednisolone group experienced significantly less pain (P = 0.027), anxiety (P = 0.018) and helplessness (P = 0.040) than control patients at 3 months. There were no renal crises, but sample size was small.

CONCLUSION

PRedSS was terminated early primarily due to the Covid-19 pandemic, and so was underpowered. Therefore, interpretation must be cautious and results considered inconclusive, indicating the need for a further randomized trial.

TRIAL REGISTRATION

ClinicalTrials.gov, https://clinicaltrials.gov, NCT03708718.

Skin involvement in early diffuse cutaneous systemic sclerosis: an unmet clinical need

Diffuse cutaneous systemic sclerosis (dcSSc) is associated with high mortality resulting from early internal-organ involvement. Clinicians therefore tend to focus on early diagnosis and treatment of potentially life-threatening cardiorespiratory and renal disease. However, the rapidly progressive painful, itchy skin tightening that characterizes dcSSc is the symptom that has the greatest effect on patients' quality of life, and there is currently no effective disease-modifying treatment for it. Considerable advances have been made in predicting the extent and rate of skin-disease progression (which vary between patients), including the development of techniques such as molecular analysis of skin biopsy samples. Risk stratification for progressive skin disease is especially relevant now that haematopoietic stem-cell transplantation is a treatment option, because stratification will inform the balance of risk versus benefit for each patient. Measurement of skin disease is a major challenge. Results from clinical trials have highlighted limitations of the modified Rodnan skin score (the current gold standard). Alternative patient-reported and other potential outcome measures have been and are being developed. Patients with early dcSSc should be referred to specialist centres to ensure best-practice management, including the management of their skin disease, and to maximize opportunities for inclusion in clinical trials.

Advances in the Treatment of Systemic Sclerosis

Although systemic sclerosis (SSc) is currently incurable, there have been recent advances in treatment. This review article begins by providing a brief background to SSc in terms of disease subtyping and autoantibodies, because both predict disease trajectory and help clinicians to select appropriate monitoring and treatment protocols. Broad principles of management are then described: ‘disease-modifying’ therapies and therapies directed at reducing disease burden and/or progression of SSc-related digital vascular disease and of internal organ involvement. Next, advances in the management of digital vasculopathy, pulmonary arterial hypertension (PAH), interstitial lung disease (ILD) and early diffuse cutaneous SSc are discussed in turn, for example: (a) increased use of phosphodiesterase inhibitors and endothelin receptor antagonists for digital vasculopathy; (b) early recognition and treatment of PAH, including with combination therapies; (c) increased use of mycophenolate mofetil and of nintedanib in ILD; and (d) immunosuppression now as standard practice in early diffuse cutaneous SSc, and autologous haematopoietic stem cell transplantation for highly selected patients with progressive diffuse disease. Finally, future challenges are discussed, including ensuring that all patients with SSc are monitored and treated according to best practice guidelines, and whenever possible giving patients the opportunity to participate in clinical trials.