# Treatment options for systemic sclerosis
Treatment of systemic sclerosis aims to slow disease progression and relieve symptoms in affected organs. Because the disease can progress very differently and affect various organs, the approach is usually tailored. The treatments discussed here are aimed at reducing fibrosis, stabilizing vascular function, and preventing or reducing complications.
Vascular treatment: Raynaud's phenomenon
**Calcium channel blockers**
ProveniIncluded in official guidelines, or approved by EMA or FDA
These medications relax blood vessels and improve blood flow to fingers and toes. They work by blocking calcium channels in the muscle tissue cells of blood vessels, reducing contraction. They are widely used as a first choice for Raynaud's attacks. Known side effects include headache, dizziness, and swelling of feet and ankles.
**Phosphodiesterase-5 inhibitors (PDE-5 inhibitors)**
ProveniIncluded in official guidelines, or approved by EMA or FDA
These substances dilate blood vessels by activating the substance cGMP. They are used for moderate to severe Raynaud's phenomena, especially when calcium channel blockers have insufficient effect. Side effects include headache, digestive problems, and painful erections.
**Endothelin receptor antagonists**
ProveniIncluded in official guidelines, or approved by EMA or FDA
These inhibit the action of endothelin, a substance that narrows blood vessels. They are classified by which receptor types they block (selective or non-selective) and can improve blood pressure reduction and blood flow. Side effects include fluid retention, headache, and liver irritation.
**Prostacyclins and treprostinil**
ProveniIncluded in official guidelines, or approved by EMA or FDA
These act as a replacement or mimic of prostacycline, a naturally occurring substance that relaxes blood vessels and prevents platelet aggregation. They improve blood flow and can be used as inhalation, infusion, or oral. Side effects depend on the route of administration; inhalation can cause sore throat, infusion often requires a centrally placed catheter.
**Inhaled treprostinil**
ResearchediPositive results in clinical studies, not yet standard treatment
An inhaled form of treprostinil is currently being investigated for symptomatic Raynaud's attacks in systemic sclerosis. Early data suggest tolerance without serious side effects in short trial periods.
**Nicotinamide (vitamin B3)**
ResearchediPositive results in clinical studies, not yet standard treatment
Recent studies suggest that nicotinamide supplementation may help with both primary and scleroderma-related Raynaud's phenomenon. The underlying mechanisms involve cellular energy metabolism and inflammation suppression. Long-term effectiveness and optimal dosing are still under investigation.
Antifibrotic and anti-inflammatory treatment
**Mycophenolate (mycophenolic acid or mofetil)**
ProveniIncluded in official guidelines, or approved by EMA or FDA
This inhibits the growth of certain white blood cells involved in fibrosis. Widely used for skin and lung involvement. It can cause gastrointestinal complaints, is well tolerated, and has been added to many national guidelines. In stem cell transplantation, it is sometimes used as follow-up treatment.
**Methotrexate**
ProveniIncluded in official guidelines, or approved by EMA or FDA
A cytostatic agent that inhibits inflammatory cells. Particularly used for skin disease in early stages and for certain forms of muscle inflammation. Side effects include nausea, bone marrow suppression, and liver irritation.
**Abatacept**
ResearchediPositive results in clinical studies, not yet standard treatment
This medication blocks T-cell activation by suppressing costimulation. Systematic reviews indicate that abatacept contributes to suppressing inflammatory processes in various autoimmune diseases, including systemic sclerosis. It is being studied particularly in combination with other agents for skin involvement.
**Bosentan and other endothelin antagonists**
ProveniIncluded in official guidelines, or approved by EMA or FDA
In addition to vascular effects, endothelin antagonists may have antifibrotic action by inhibiting fibroblast growth. Bosentan and others in this group can be used in early skin and lung disease.
**FGF/FGFR signaling inhibitors**
ResearchediPositive results in clinical studies, not yet standard treatment
Growth-dependent signaling pathways, particularly via FGF receptor, play a role in fibrosis and inflammatory reactions. Research focuses on how modulation of these pathways can influence both tissue remodeling and immune function. This remains largely experimental territory.
Lung involvement
**Cyclophosphamide**
ProveniIncluded in official guidelines, or approved by EMA or FDA
A potent cytostatic agent used for progressive interstitial lung disease. It can slow fibrosis progression and better preserve lung function. Severe side effects include bladder inflammation, infertility, and lung damage; intensive monitoring is essential.
**Mycophenolate**
ProveniIncluded in official guidelines, or approved by EMA or FDA
Increasingly used as an alternative to cyclophosphamide, with a more favorable side effect profile. Studies show equivalent effects on lung function in certain patient groups.
**Antifibrotic agents (pirfenidone, nintedanib)**
ProveniIncluded in official guidelines, or approved by EMA or FDA
These inhibit specific fibrosis mechanisms in lung tissue. They are used in progressive idiopathic pulmonary fibrosis and research is expanding their application in scleroderma-associated lung disease. Side effects include gastrointestinal issues, photosensitivity, and liver changes.
**Exhaled nitric oxide monitoring**
ProveniIncluded in official guidelines, or approved by EMA or FDA
This is not a treatment, but rather a diagnostic technique to detect inflammatory activity in the lungs in connective tissue diseases. Elevated NO values can signal that inflammatory activity is increasing and therapy adjustment may be needed.
Kidney and renal crisis protection
**ACE inhibitors**
ProveniIncluded in official guidelines, or approved by EMA or FDA
Crucial treatment for scleroderma renal crisis. They inhibit the angiotensin system and prevent vascular damage in the kidney. They have proven life-saving and are started as soon as kidney involvement is detected, even without probable crisis. Side effects include low blood pressure, chronic cough, and elevated potassium.
Gastrointestinal inflammation and fibrosis
**Proton pump inhibitors**
ProveniIncluded in official guidelines, or approved by EMA or FDA
Suppress stomach acid production. Many systemic sclerosis patients have acid reflux due to reduced esophageal motility; PPIs provide protection against erosion. Long-term use can cause vitamin B12 and magnesium deficiency.
**Prokinetic agents**
ProveniIncluded in official guidelines, or approved by EMA or FDA
These enhance gastrointestinal motility and help move food forward when normal contractions are weak. They are used when reflux and esophageal dysmotility cause symptoms.
**Immunosuppression in gastrointestinal fibrosis**
ResearchediPositive results in clinical studies, not yet standard treatment
Recent observations suggest that mycophenolate and other anti-inflammatory agents may help slow GI fibrosis progression. The underlying mechanism involves inhibition of fibroblast activation and inflammatory cytokines.
Stem Cell Transplantation
**Autologous stem cell transplantation (ASCT)**
ProveniIncluded in official guidelines, or approved by EMA or FDA
This is an intensive form of treatment in which stem cells are collected from the patient's bone marrow, the immune system is eliminated ('depleted'), and the stem cells are then reinfused. This 'resets' the immune system. ASCT can significantly halt fibrosis progression in suitable patients with early-stage, active skin and lung disease. Side effects can be severe (infections, bone marrow damage, long-term infertility). After ASCT, mycophenolate is often given to prevent relapse.
Research and future directions
**CTX112 (CAR-T cell therapy targeting B cells)**
ExperimentaliOngoing in study setting, outcome still unknown
This gene therapy product works by selectively eliminating B lymphocytes that produce autoantibodies. It is being tested in phase 2 trials for refractory autoimmune diseases, including systemic sclerosis.
**NKX019**
ExperimentaliOngoing in study setting, outcome still unknown
A new agent that targets B cells at a different point of engagement. Phase 1/2 studies are investigating safety and efficacy in immune-mediated diseases.
**Nerandomilast**
ExperimentaliOngoing in study setting, outcome still unknown
This agent targets phosphodiesterases and inflammatory cascades. It is currently being investigated for systemic sclerosis based on earlier evidence that it may influence tissue fibrosis and vascular dysfunction.
**Pyruvate kinase M2 modulation**
ExperimentaliOngoing in study setting, outcome still unknown
Recent research shows that this enzyme is elevated in systemic sclerosis and involved in disease pathogenesis. Potential therapeutic inhibitors of this enzyme are still in preclinical stages, but constitute a research area that can offer new insights.
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_This information never replaces a doctor's judgment. Always discuss your situation with your own healthcare provider._