Current drug therapy for scleroderma and secondary Raynaud's phenomenon: evidence-based review

Inhibiting Intracellular α2C-Adrenoceptor Surface Translocation Using Decoy Peptides: Identification of an Essential Role of the C-Terminus in Receptor Trafficking

The G protein-coupled α2-adrenoceptor subtype C (abbreviated α2C-AR) has been implicated in peripheral vascular conditions and diseases such as cold feet-hands, Raynaud's phenomenon, and scleroderma, contributing to morbidity and mortality. Microvascular α2C-adrenoceptors are expressed in specialized smooth muscle cells and mediate constriction under physiological conditions and the occlusion of blood supply involving vasospastic episodes and tissue damage under pathological conditions. A crucial step for receptor biological activity is the cell surface trafficking of intracellular receptors, triggered by cAMP-Epac-Rap1A GTPase signaling, which involves protein-protein association with the actin-binding protein filamin-2, mediated by critical amino acid residues in the last 14 amino acids of the receptor carboxyl (C)-terminus. This study assessed the role of the C-terminus in Rap1A GTPase coupled receptor trafficking by domain-swapping studies using recombinant tagged receptors in transient co-transfections and compared with wild-type receptors using immunofluorescence microscopy. We further tested the biological relevance of the α2C-AR C-terminus, when introduced as competitor peptides, to selectively inhibit intracellular α2C-AR surface translocation in transfected as well as in microvascular smooth muscle cells expressing endogenous receptors. These studies contribute to establishing proof of principle to target intracellular α2C-adrenoceptors to reduce biological activity, which in clinical conditions can be a target for therapy.

Incidence and Predictors of an Abnormal Liver Function Test Among 674 Systemic Sclerosis Patients: A Cohort Study

Background

Abnormal liver function tests (LFTs) can indicate cirrhosis or liver cancer leading to mortality among systemic sclerosis (SSc) patients. No recent studies have investigated the clinical predictors of an abnormal LFT in SSc. We aimed to determine the incidence of abnormal LFT (including from hepatitis and cholestasis) and to identify its clinical predictors in SSc patients.

Methods

An historical cohort was conducted on 674 adult SSc patients who attended the Scleroderma Clinic, Khon Kaen University, between January 2012 and November 2019 and who underwent routine screening for LFT. A Cox regression was used to analyze the clinical predictors of abnormal LFT.

Results

Four hundred and thirty cases, representing 4190 person-years, had abnormal LFTs (viz, from hepatitis, cholestasis, and cholestatic hepatitis) for an incidence rate of 10.2 per 100 person-years. The respective incidence of hepatitis, cholestasis, and cholestatic hepatitis was 20.5, 12.9, and 20.4 per 100 person-years. The respective median first-time detection of hepatitis, cholestasis, and cholestatic hepatitis was 3.0, 5.9, and 2.8 years, and none had signs or symptoms suggestive of liver disease. According to the Cox regression analysis, the predictors of an abnormal LFT in SSc were elderly onset of SSc (hazard ratio (HR) 1.02), alcoholic drinking (HR 1.74), high modified Rodnan Skin Score (mRSS) (HR 1.03), edematous skin (HR 2.94), Raynaud's phenomenon (HR 1.39), hyperCKaemia (HR 1.88), and methotrexate use (HR 1.55). In contrast, current sildenafil treatment (HR 0.63) and high serum albumin (HR 0.70) were protective factors.

Conclusion

Occult hepatitis, cholestasis, and cholestatic hepatitis can be detected in SSc patients using LFT screening, especially in cases of early disease onset. The long-term outcome is uncertain, and more longitudinal research is required.

Impact of Connective Tissue Disease on Oncologic Breast Surgery and Reconstruction

BACKGROUND

The impact of connective tissue disease (CTD) on outcomes following breast surgery and reconstruction is unknown. The purpose of this study was to evaluate the effect of both CTDs and systemic immunomodulatory therapy on outcomes following breast surgery and reconstruction.

METHODS

A retrospective review was performed of all patients from 2005 to 2010 with an active CTD who underwent breast surgery with or without reconstruction. Surgical events were assigned to 1 of 4 groups: ablative surgery alone, autologous reconstruction, implant reconstruction, and revision surgery. Logistic regression was utilized to examine the relationship between complications and type of surgery, CTD diagnosis, and immunomodulatory therapy. Four non-CTD control groups were then compiled for outcome comparison. The a priori P-value was set at P < 0.05, and all tests were 2 sided.

RESULTS

Thirty-three patients with CTD underwent112 procedures. Diagnoses included psoriasis/psoriatic arthritis (n = 12), rheumatoid arthritis (n = 10), lupus (n = 4), scleroderma (n = 3), Sjogren syndrome (n = 2), mixed CTD (n = 1), and seronegative polyarthritis (n = 1). Nineteen of 33 (58%) patients who received systemic treatment for CTD in the perioperative period were less likely to experience a minor complication compared with those without treatment (odds ratio= 0.69; P = 0.019). There were no differences in postoperative complications in patients with CTD compared with control groups.

CONCLUSIONS

Ablative breast surgery and reconstruction among patients with CTDs can be performed safely with low perioperative complication rates. Patients receiving systemic therapy, and continuing their regimens perioperatively, experience complication rates similar to those not requiring therapy.

A non-invasive technique for the evaluation of peripheral circulatory functions in female subjects with Raynaud's phenomenon

Japanese women now account for 43 percent of the labor force. A number of them are involved in construction, agricultural and forestry jobs. The aim of this study was to establish a non-invasive technique for the evaluation of peripheral circulatory functions in women with Raynaud's phenomenon (RP) and introduce a specific method for the assessment of vascular disturbances in females exposed to hand-transmitted vibration. The subjects of this study were 10 women with primary RP, 7 women with progressive systemic sclerosis (PSS) secondary to RP, and 17 females who were included as the control group. The evaluation of peripheral circulatory functions in all subjects was based on the values of finger blood flow (FBF) and finger skin temperature (FST) measured before, during and following a 5-min recovery period after the hand was immersed in cold water (5°C, 1 min). The measured values of FBF and FST of the primary RP group before and after the immersion test were significantly (p<0.01) lower compared to those of the control group. The technique applied in this study could be used as a non-invasive and tolerable technique to determine the digital circulatory functions in female subjects with RP.

Raynaud's Phenomenon: A Brief Review of the Underlying Mechanisms

Raynaud’s phenomenon (RP) is characterized by exaggerated cold-induced vasoconstriction. This augmented vasoconstriction occurs by virtue of a reflex response to cooling via the sympathetic nervous system as well as by local activation of α_2C adrenoceptors (α_2C-AR). In a cold-initiated, mitochondrion-mediated mechanism involving reactive oxygen species and the Rho/ROCK pathway, cytoskeletal rearrangement in vascular smooth muscle cells orchestrates the translocation of α_2C-AR to the cell membrane, where this receptor readily interacts with its ligand. Different parameters are involved in this spatial and functional rescue of α_2C-AR. Of notable relevance is the female hormone, 17β-estradiol, or estrogen. This is consistent with the high prevalence of RP in premenopausal women compared to age-matched males. In addition to dissecting the role of these various players, the contribution of pollution as well as genetic background to the onset and prevalence of RP are also discussed. Different therapeutic approaches employed as treatment modalities for this disease are also highlighted and analyzed. The lack of an appropriate animal model for RP mandates that more efforts be undertaken in order to better understand and eventually treat this disease. Although several lines of treatment are utilized, it is important to note that precaution is often effective in reducing severity or frequency of RP attacks.

A Randomized Controlled Trial of Acupressure for the Treatment of Raynaud's Phenomenon: The difficulty of conducting a trial in Raynaud's phenomenon

OBJECTIVE

To examine the effect of acupressure on Raynaud's phenomenon (RP) in a randomized controlled clinical trial (RCT) and to evaluate the difficulties of conducting a RP RCT.

METHODS

A pilot single center RCT of acupressure vs. targeted patient education was conducted for the treatment of RP. Patients with either primary (N = 15) or secondary (N = 8) RP were randomized in an 8-week study. The primary endpoints included a decrease in the frequency and duration of RP. Secondary endpoints included several serum biomarkers including endothelial dysfunction, Raynaud's attack symptoms, Raynaud's Condition Score, and patient and physician global assessments of RP. Primary data analysis was conducted using the last observation carried forward and t-tests or a Wilcoxon rank test was used to compare the two groups.

RESULTS

23 patients were randomized and 7 discontinued prematurely. 78% of patients were female, 96% were Caucasian, and the mean age was 49.8 (SD=16) years. No statistically significant differences were detected between the acupressure vs. education groups in primary and secondary outcomes (p> 0.05). Frequency of attacks decreased by 6.7 attacks (SD=8.8) in the acupressure group vs. 7.2 (SD=12.8) in the education group (p=0.96), and the duration of attacks decreased by 11.4 (SD=19.9) minutes in the acupressure group vs. an increase of 0.8 minutes (SD=11.2) in the education group (p=0.14). There were no adverse events noted in the RCT.

CONCLUSION

This pilot study does not support efficacy of acupressure for RP.

Cutaneous Markers of Systemic Disease in the Lower Extremity

The skin of the lower extremity can be a helpful diagnostic tool for systemic disease. Diabetes, renal disease, genetic disorders, and even cancer can have cutaneous manifestations in the legs and feet; moreover, proper diagnosis can facilitate earlier treatment of these diseases and not only clear up the skin symptoms but also bring about resolution of the systemic disease causing them. Although not comprehensive, this article discusses many of these disorders presenting with integumentary manifestations in the lower extremities. Where appropriate, it also enumerates the treatments involved, both systemic and localized.

The role of botulinum toxin in vasospastic disorders of the hand

Raynaud phenomenon may be a primary disorder or associated with a variety of other autoimmune processes. Raynaud phenomenon produces digital vasospasm, which can lead to ischemia and ulceration. The treatment of Raynaud phenomenon has been difficult because multiple medical treatments have not provided uniform resolution of symptoms. Many patients have turned to surgery and sympathectomies for the treatment of unrelenting vasospasm. Botulinum toxin has been shown to be an effective alternative to surgery, with a single treatment being capable of resolving pain and healing ulcer. This article reviews the use of botulinum toxin for the treatment of Raynaud phenomenon.

Twenty-two points to consider for clinical trials in systemic sclerosis, based on EULAR standards

OBJECTIVE

SSc is clinically and aetiopathogenically heterogeneous. Consensus standards for more uniform trial design and selection of outcome measures are needed. The objective of this study was to develop evidence-based points to consider (PTCs) for future clinical trials in SSc.

METHODS

Thirteen international SSc experts experienced in SSc clinical trial design were invited to participate. One researcher with experience in systematic literature review and three trainees were also included. A systematic review using PubMed and the Cochrane Central Register of Controlled Trials was conducted and PTCs when designing clinical trials in SSc were developed. As part of that development we conducted an Internet-based Delphi exercise regarding the main points to be made in the consensus statement. Consensus was defined as achieving a median score of ≥7 of 9.

RESULTS

By consensus, the experts decided to develop PTCs for each individual organ system. The current document provides a unifying outline on PTCs regarding general trial design, inclusion/exclusion criteria and analysis. Consensus was achieved regarding all the main points of the PTCs.

CONCLUSION

Using European League Against Rheumatism suggestions for PTCs, a general outline for PTCs for controlled clinical trials in SSc was developed. Specific outlines for individual organ systems are to be published separately. This general outline should lead to more uniform and higher-quality trials and clearly delineate areas where further research is needed.

Minimally invasive treatment of Raynaud phenomenon: the role of botulinum type A

Although the mechanism is unknown, Btx-A injection may be an effective, localized, nonsurgical treatment option without addictive properties or systemic side effects for the treatment of ischemic digits. Clinical research supports the safety and efficacy of injection of Btx-A for the treatment of Raynaud phenomenon.

The primary care physician in the early diagnosis of systemic sclerosis: the cornerstone of recognition and hope

Systemic sclerosis (SSc) is a disease of unknown causative factor that manifests as a heterogenous group of multiorgan system manifestations and is characterized by vasculopathy and fibrosis of the skin and internal organs, with mortality related to pulmonary, cardiac, renal or gastrointestinal involvement. The prevalence of SSc may be underestimated in the general population. Cases are often undiagnosed or misdiagnosed, particularly cases with mild or no skin manifestations. Because of late referrals to rheumatologic care, many moderate-to-severe cases progress to irreversible end-organ damage that might have been prevented by early diagnosis. Early diagnosis of SSc with initiation of appropriate treatment is essential, with great impact on morbidity and mortality. This review examines presenting features, ensuing complications and treatment providing a focus on SSc as a treatable disease. Primary care providers play a pivotal role in recognizing initial symptoms associated with SSc and securing early diagnosis through early referral to specialists.

Latest advances in connective tissue disorders

The connective tissue disorders comprise a number of related conditions that include systemic lupus erythematosus (SLE) and the antiphospholipid (Hughes) syndrome, scleroderma, myositis and Sjögren's syndrome. They are characterized by autoantibody production and other immune-mediated dysfunction. There are common clinical and serological features with some patients having multiple overlapping connective tissue disorders. The latest advances include new approaches to therapy, including more focused utilization of existing therapies and the introduction of biological therapies in SLE, more precise protocols for assessment of severe disease manifestations such as in interstitial lung disease and pulmonary artery hypertension in scleroderma, new antibodies for disease characterization in myositis and new approaches to patient assessment in Sjögren's syndrome. B cells have a critical role in most, if not all of these disorders such that B-cell depletion or suppression of B-cell activating cytokines improves disease in many patients. In particular, the introduction of rituximab, a monoclonal antibody targeting the CD20 molecule on B cells, into clinical practice for rheumatoid arthritis and B-cell lymphoma has been a key driver of experimental approaches to therapy in connective tissue disorders. Genetic studies also suggest a role for the innate immune system in disease pathogenesis, suggesting further future targets for biological therapies over the next few years.

Evaluation of test characteristics for outcome measures used in Raynaud's phenomenon clinical trials

OBJECTIVE

Randomized controlled trials (RCTs) in Raynaud's phenomenon (RP) have shown conflicting efficacy data. Also, there is no consensus on the outcome measures that should be used. Our objectives were to assess the reliability of individual core set measures used in 3 RCTs, evaluate the placebo response for individual core set measures, and determine if a composite of individual core set measures will decrease the placebo response, which may improve our ability to see treatment effects in future trials.

METHODS

We analyzed core set measures from 249 patients in the placebo-treated groups from 3 RCTs. Core set measures analyzed included the Raynaud's Condition Score (RCS); patient and physician assessment of RP; pain, numbness, and tingling during an RP attack; average number of attacks/day; and duration of attacks. Intraclass correlation coefficients (ICCs) were calculated during the run-in period to the RCTs.

RESULTS

ICCs of ≥0.70 were observed for the RCS, attack symptoms, and average attacks/day. A high placebo response rate was observed for all individual core measures except the duration of attacks. For the RCS, the placebo response ranged from 56% with ≥10% improvement to 19.5% with ≥60% improvement. In contrast, placebo response rates of 10-20% were observed when several core set measures were combined to develop a composite score.

CONCLUSION

Outcome measures used in RCTs of RP are associated with marked variability. A combination of outcome measures is associated with low placebo responses. Future studies are needed to assess if a composite score will be able to differentiate placebo from an effective agent.

Scleroderma therapy: clinical overview of current trends and future perspective

Systemic sclerosis is a chronic autoimmune condition with a complex pathogenesis and a high rate of mortality and morbidity. Internal organ involvement requires interdisciplinary approach in individual patient management. New discoveries in the pathogenesis of scleroderma herald a drastic change in the traditional outlook to therapy and have led to the development of the target-based approach in management. The challenge at present is to translate these advances in molecular mechanisms into well-designed clinical trials that will recognize potential disease-modifying therapies. This article is an evidence-based review of prevailing treatment options and future therapeutic targets in systemic sclerosis.

Assessing microvascular changes in systemic sclerosis diagnosis and management

Microvascular damage and dysfunction represent the earliest morphological and functional markers of systemic sclerosis (SSc), a progressive connective tissue disease characterized by vascular abnormalities and diffuse fibrosis in the skin and internal organs. These early microvascular changes are clinically mirrored by Raynaud phenomenon, which can be primary (idiopathic) or secondary to several different conditions including SSc. Morphological and functional assessment of the cutaneous microvasculature have crucial implications for diagnosis, prognosis and therapy in SSc and secondary Raynaud phenomenon. Most importantly, imaging with nailfold videocapillaroscopy (NVC) enables the early differentiation between primary and secondary Raynaud phenomenon by identifying morphological patterns specific to various stages of SSc ('early', 'active' and 'late' patterns); the inclusion of these NVC patterns could increase the sensitivity of classification criteria for SSc. Findings on NVC are also markers of SSc severity and progression, as reduced capillary density has been associated with a high risk of developing digital skin ulcers and pulmonary arterial hypertension. Laser Doppler imaging and thermal imaging demonstrate the dysfunctional cutaneous blood flow in response to cold stimuli. Therapies targeting underlying vascular disease in SSc have been successfully designed to improve the symptoms of Raynaud phenomenon and to reduce ischemic injury to involved organs, and NVC patterns have been found to improve following targeted therapy; however, treatment of later fibrosis remains a challenge.

Attenuation of fibrosis in vitro and in vivo with SPARC siRNA

Introduction

SPARC is a matricellular protein, which, along with other extracellular matrix components including collagens, is commonly over-expressed in fibrotic diseases. The purpose of this study was to examine whether inhibition of SPARC can regulate collagen expression in vitro and in vivo, and subsequently attenuate fibrotic stimulation by bleomycin in mouse skin and lungs.

Methods

In in vitro studies, skin fibroblasts obtained from a Tgfbr1 knock-in mouse (TBR1^CA; Cre-ER) were transfected with SPARC siRNA. Gene and protein expressions of the Col1a2 and the Ctgf were examined by real-time RT-PCR and Western blotting, respectively. In in vivo studies, C57BL/6 mice were induced for skin and lung fibrosis by bleomycin and followed by SPARC siRNA treatment through subcutaneous injection and intratracheal instillation, respectively. The pathological changes of skin and lungs were assessed by hematoxylin and eosin and Masson's trichrome stains. The expression changes of collagen in the tissues were assessed by real-time RT-PCR and non-crosslinked fibrillar collagen content assays.

Results

SPARC siRNA significantly reduced gene and protein expression of collagen type 1 in fibroblasts obtained from the TBR1^CA; Cre-ER mouse that was induced for constitutively active TGF-β receptor I. Skin and lung fibrosis induced by bleomycin was markedly reduced by treatment with SPARC siRNA. The anti-fibrotic effect of SPARC siRNA in vivo was accompanied by an inhibition of Ctgf expression in these same tissues.

Conclusions

Specific inhibition of SPARC effectively reduced fibrotic changes in vitro and in vivo. SPARC inhibition may represent a potential therapeutic approach to fibrotic diseases.

Rapamycin versus methotrexate in early diffuse systemic sclerosis: results from a randomized, single-blind pilot study

OBJECTIVE

To assess the safety and efficacy of rapamycin in the treatment of diffuse systemic sclerosis (SSc; scleroderma).

METHODS

Eighteen patients with diffuse SSc of <or=5 years duration were randomized to receive rapamycin or methotrexate (MTX) in a single-blind, 48-week study. Abnormalities in clinical and laboratory parameters were compared between the 2 treatment groups. The potential efficacy of the study drugs was evaluated by comparing results of the baseline and 48-week assessments, including the modified Rodnan skin thickness score (MRSS) and the Health Assessment Questionnaire disability index.

RESULTS

The baseline characteristics of the patients were similar in both groups (n=9 in each). One patient in the rapamycin group who never received the study drug was excluded from the analysis. Three patients in each group withdrew from the study; 2 of the withdrawals were treatment-related (severe hypertriglyceridemia associated with rapamycin, and pancytopenia associated with MTX), and 4 were SSc-related. Hypertriglyceridemia was the most notable side effect associated with rapamycin, but it was generally well tolerated and treatable. The incidence and severity of other adverse drug reactions were comparable between the 2 groups. Within each group, the MRSS improved significantly from baseline. In the rapamycin group, the patient's global assessment showed a significant improvement from baseline, while forced vital capacity values declined from baseline. The disease activity scores at 48 weeks and the changes in these scores from baseline were not significantly different between the 2 groups.

CONCLUSION

Rapamycin has a reasonable safety profile in a select group of patients with scleroderma. Larger trials are needed to assess the efficacy of rapamycin in patients with early diffuse SSc.

Three-dimensional electrocardiographically gated variable flip angle FSE imaging for MR angiography of the hands at 3.0 T: initial experience

After institutional review board approval and informed consent were obtained for this HIPAA-compliant investigation, a three-dimensional electrocardiographically gated variable flip angle (VFA) fast spin-echo magnetic resonance (MR) angiography technique was evaluated as an unenhanced method for imaging hand arteries in 13 subjects (including four patients) at 3.0 T; this included evaluation of vessel visualization with warming and cooling in seven subjects. Examinations were evaluated for image quality and vessel conspicuity. Clear separation of arteries from veins was achieved in all subjects, with excellent vessel conspicuity and depiction of stenoses. Warming improved vessel visualization in healthy volunteers. VFA MR angiography is a high-spatial-resolution technique that enables the assessment of vascular reactivity in response to temperature challenge.

Cognitive and cerebral hemodynamic impairment in scleroderma patients

BACKGROUND AND PURPOSES

Neurological involvement in systemic sclerosis is unusual despite the possible cerebral localization of vascular lesions. The aim of this study was to evaluate cognitive performances and cerebral vasoreactivity in young scleroderma patients without any signs or symptoms of nervous system involvement.

METHODS

Sixteen scleroderma patients and 16 sex- and age-matched healthy subjects without vascular risk factors were included. A neuropsychological assessment for the evaluation of different areas of cognition was performed. For an assessment of cerebrovascular reactivity (CVR), each subject was submitted to hypercapnia with transcranial Doppler ultrasonography using the Breath-Holding Index (BHI).

RESULTS

Patients had significantly lower adjusted mean levels of performance with respect to controls in the Modified Card Sorting Test (P < 0.001) and in the Trail Making Test Parts A and B (P < 0.001 and P < 0.05 respectively). Regarding CVR, BHI values were significantly lower in patients with respect to controls: 0.82 +/- 0.44 vs. 1.34 +/- 0.18, P < 0.0001.

CONCLUSIONS

These findings show the presence of reduced performances of executive functions in scleroderma patients. The associated alteration of CVR in the absence of other apparent causes of cerebrovascular impairment suggests that cognitive problems may be related to an alteration in cerebral perfusion regulation specifically linked to the disease. Further studies are needed to evaluate whether cognitive changes may be positively influenced by treatments aimed to improve vessels functionality in scleroderma patients.

Pentoxyphylline in association with vitamin E reduces cutaneous fibrosis in systemic sclerosis

Systemic sclerosis (SSc) is a disorder characterized by skin thickness and vasculopathy. The objective of the study was to evaluate the therapeutic effect and safety of the association of pentoxyphylline and vitamin E in SSc patients. Twelve SSc patients (American College of Rheumatology criteria) enrolled this 24-week open-label study. Patients received daily 800 mg of pentoxyphylline and 800 UI of vitamin E and were evaluated at 4-week interval. The primary efficacy endpoint was the change in Modified Rodnan Skin Score (MRSS) at week 24. Nine diffuse SSc patients treated 6 months with cyclophosphamide were used as a historical control group. The mean age of the treated group was 43.6 years, and ten of 12 (84%) patients were women. Their mean MRSS reduced from 25.7 to 18.7 (p = 0.03) at 16th week and remained significantly reduced throughout the study. In contrast, only a trend of MRSS reduction was observed in the historical control group (p = 0.06). Two patients started the study with active ischemic ulcers and ended with a complete healing of them. No serious side effects were reported. Pentoxyphylline and vitamin E might be an alternative therapeutic approach in SSc patients.

Endothelin: 20 years from discovery to therapy

Since its identification as an endothelial cell-derived vasoconstrictor peptide in 1988, endothelin-1, the predominant member of the endothelin peptide family, has received considerable interest in basic medical science and in clinical medicine, which is reflected by more than 20 000 scientific publications on endothelin research in the past 20 years. The story of endothelin is unique as the gene sequences of endothelin receptors and the first receptor antagonists became available within only 4 years of the identification of the peptide sequence. The first clinical study in patients with congestive heart failure was published only 3 years thereafter. Yet, despite convincing experimental evidence of a pathogenetic role for endothelin in development, cell function, and disease, many initial clinical studies on endothelin antagonism were negative. In many of these studies, study designs or patient selection were inadequate. Today, for diseases such as pulmonary hypertension, endothelin antagonist treatment has become reality in clinical medicine, and ongoing clinical studies are evaluating additional indications, such as renal disease and cancer. Twenty years after the discovery of endothelin, its inhibitors have finally arrived in the clinical arena and are now providing us with new options to treat disease and prolong the lives of patients. Possible future indications include resistant arterial hypertension, proteinuric renal disease, cancer, and connective tissue diseases.