Biologics in dermatology: an integrated review

A Systematic Review and Meta-Analysis of Injection Site Reactions in Randomized-Controlled Trials of Biologic Injections

BACKGROUND

Biologic agents are emerging as an important treatment option for immune-mediated diseases. Injection site reactions following subcutaneous injection of biologic agents is not well described in the literature.

OBJECTIVE

To summarize injection site reaction data in phase 3 trials of all biologic agents.

METHODS

MEDLINE, Embase, and CENTRAL databases were systematically searched on February 8, 2022. Proportional meta-analysis was conducted to summarize injection site reaction prevalence for each biologic.

RESULTS

There were 158 articles included in the review. The most common types of injection site reactions were erythema (42.8%), unspecified reaction (23.3%), pain (12.4%), and pruritus (5.7%). No patients discontinued their treatment due to injection site reactions in 39 of the 48 studies that reported on discontinuation data. There were 16 biologics included in meta-analysis across 80 eligible studies. The biologics with the highest point prevalence of patients reporting injection site reactions were Canakinumab (15.5%; 294 patients), Dupilumab (11.4%; 1888 patients), Etanercept (11.4%; 4363 patients), and Ixekizumab (11.2%; 2205 patients). The biologics with the lowest point prevalence of injection site reactions were Risankizumab (0.8%; 707 patients), Brodalumab (1.3%; 1365 patients), Guselkumab (1.3%; 1852 patients), Secukinumab (1.9%; 1277 patients).

CONCLUSIONS

The prevalence of injection site reaction in response to biologics ranges from 0.08 to 15.5%. Canakinumab, Dupilumab, Etanercept, and Ixekizumab had the highest prevalence of injection site reactions. Risankizumab, Brodalumab, Guselkumab, and Secukinumab had the lowest prevalence of injection site reactions. Recommendations are made regarding the improvement of adverse event reporting to better understand the epidemiology of injection site reactions.

Impact of gut microbiome on skin health: gut-skin axis observed through the lenses of therapeutics and skin diseases

The human intestine hosts diverse microbial communities that play a significant role in maintaining gut-skin homeostasis. When the relationship between gut microbiome and the immune system is impaired, subsequent effects can be triggered on the skin, potentially promoting the development of skin diseases. The mechanisms through which the gut microbiome affects skin health are still unclear. Enhancing our understanding on the connection between skin and gut microbiome is needed to find novel ways to treat human skin disorders. In this review, we systematically evaluate current data regarding microbial ecology of healthy skin and gut, diet, pre- and probiotics, and antibiotics, on gut microbiome and their effects on skin health. We discuss potential mechanisms of the gut-skin axis and the link between the gut and skin-associated diseases, such as psoriasis, atopic dermatitis, acne vulgaris, rosacea, alopecia areata, and hidradenitis suppurativa. This review will increase our understanding of the impacts of gut microbiome on skin conditions to aid in finding new medications for skin-associated diseases.

Alternative uses of ustekinumab for non-indicated dermatological conditions: a systematic review

Ustekinumab is approved for the treatment of psoriasis and Crohn's disease. Because many dermatological conditions are due to immune-mediated development, ustekinumab may be effective in other conditions. A systematic review of the off-label uses of ustekinumab, as well as on-label adverse effect, was performed, reporting on clinical improvement. MEDLINE, Embase, Web of Science, and Cochrane databases were searched for studies regarding ustekinumab treatment of rativa (HS), lichen planus (LP), pyoderma gangrenosum (PG), pityriasis rubra pilaris (PRP), cutalopecia areata (AA), atopic dermatitis (AD), Bechet's disease, bullous pemphigoid (BP), hidradenitis suppuaneous sarcoidosis, cutaneous systemic lupus erythematosus (SLE), and vitiligo. Descriptive statistics were performed. 74 articles of 4596 screened were included, and reported on 212 patients receiving ustekinumab treatment. Across all studies, ustekinumab showed promise in treating patients: AA (10/12 patients; 83.3% improvement), AD (28/74 patients; 37.8% improvement), HS (42/52 patients; 80.8% improvement), and PRP (25/27 patients; 92.6% improvement), among others. Adverse events were noted with the use of ustekinumab, including development of AA (four patients), AD (three patients), and BP (four patients), among others. Ustekinumab can be a promising option for patients with dermatological conditions refractory to traditional therapies. Adverse events must be monitored in certain patients.

Gene Co-expression Networks Identifies Common Hub Genes Between Cutaneous Sarcoidosis and Discoid Lupus Erythematosus

In this study we analyzed gene co-expression networks of three immune-related skin diseases: cutaneous sarcoidosis (CS), discoid lupus erythematosus (DLE), and psoriasis. We propose that investigation of gene co-expression networks may provide insights into underlying disease mechanisms. Microarray expression data from two cohorts of patients with CS, DLE, or psoriasis skin lesions were analyzed. We applied weighted gene correlation network analysis (WGCNA) to construct gene-gene similarity networks and cluster genes into modules based on similar expression profiles. A module of interest that was preserved between datasets and corresponded with case/control status was identified. This module was related to immune activation, specifically leukocyte activation, and was significantly increased in both CS lesions and DLE lesions compared to their respective controls. Protein-protein interaction (PPI) networks constructed for this module revealed seven common hub genes between CS lesions and DLE lesions: TLR1, ITGAL, TNFRSF1B, CD86, SPI1, BTK, and IL10RA. Common hub genes were highly upregulated in CS lesions and DLE lesions compared to their respective controls in a differential expression analysis. Our results indicate common gene expression patterns in the immune processes of CS and DLE, which may have indications for future therapeutic targets and serve as Th1-mediated disease biomarkers. Additionally, we identified hub genes unique to CS and DLE, which can help differentiate these diseases from one another and may serve as unique therapeutic targets and biomarkers. Notably, we find common gene expression patterns in the immune processes of CS and DLE through utilization of WGCNA.

Dermatological aspects of SARS-CoV-2 infection: mechanisms and manifestations

The human infection caused by the novel SARS-CoV-2 is a public health emergency of international concern. Although the disease associated to this virus, named COVID-19, mainly affects the lungs, the infection can spread to extrapulmonary tissues, causing multiorgan involvement in severely ill patients. The broad infective capacity of SARS-CoV-2 is related to the pattern of expression of the viral entry factors ACE2 and TMPRSS2 in human tissues. As such, the respiratory and gastrointestinal tracts are at high risk for SARS-CoV-2 infection due to their high expression of ACE2 and TMPRSS2, which explains the clinical phenotype described in the vast majority of infected patients that includes pneumonia and diarrhea. Recently, preoccupation about the potential of the virus to infect the skin has been raised by dermatologists due to the increasing observations of cutaneous manifestations in patients with SARS-CoV-2 infection. Although there is little evidence of the expression of ACE2 and TMPRSS2 in the normal skin, the dermatological findings observed among COVID-19 patients warrants further investigation to delineate the mechanisms of skin affection after SARS-CoV-2 infection. Here, we provide a summary of the dermatological findings observed among patients with laboratory-confirmed SARS-CoV-2 infection based on recent reports. In addition, we analyze possible mechanisms of skin injury in COVID-19 patients and discuss about the risk of individuals with chronic skin conditions for SARS-CoV-2 infection. The present review constitutes a useful informative tool to improve our understanding of the pathophysiological mechanisms of COVID-19 and the possible implications of the current pandemic in dermatology.

Hypersensitivity reactions to biologics (part I): allergy as an important differential diagnosis in complex immune-derived adverse events

Purpose

Biotechnological substances (BSs) are strongly relied upon to prevent rejection of transplanted organs, and to treat oncological, allergological, and other inflammatory diseases. Allergic reactions to partly foreign biologics can occur due to their potential immunogenicity. The severity of an immune response to a biological drug may range from no clinical significance to a severe, life-threatening anaphylactic reaction.

Methods

Detailed searches were performed on Pubmed, Web of Science, and Google Scholar to include all available publications. In addition, the Food and Drug Administration, the European Medicines Agency, and British Columbia Cancer Agency Drug Manual databases were screened for hypersensitivity reaction (HSR), infusion reaction, injection site reaction, urticaria, and anaphylaxis for individual BSs.

Results

Treatment with BSs can cause various types of HSR. These are mentioned in the literature with definitions such as allergic reactions, anaphylactoid reactions, anaphylaxis, HSR, infusion reactions, injection site reactions, cytokine release syndrome, and urticaria. Due to the overlap in signs and symptoms in the reported descriptions, it is not always possible to differentiate these reactions properly according to their pathomechanism. Similarly, many data reported as anaphylaxis actually describe severe anaphylactic reactions (grades III or IV).

Conclusion

There is an urgent need for a simpler symptom- or system-based classification and scoring system to create an awareness for HSRs to BSs. A better understanding of the pathophysiology of HSRs and increased clinical experience in the treatment of side effects will provide timely control of unexpected reactions. As a result, immunotherapy with BSs will become safer in the future.

Surgical Upper Extremity Infections in Immunosuppressed Patients: A Comparative Analysis With Diagnosis and Treatment Recommendations for Hand Surgeons

Background: Immunosuppression is encountered in patients with oncologic, transplant, and autoimmune disorders. The purpose of this study is to provide guidance for physicians treating surgical hand and upper extremity (UE) infections in immunosuppressed (IS) patients. Methods: We retrospectively reviewed our database of patients presenting with UE infections over 3 years. IS patients were matched randomly to non-IS patients. Patient background, infection presentation, surgical evaluation, and microbiology variables were recorded. Infection variables included mechanism, location, and type. Outcomes included inpatient length of stay (LOS) and need for repeat drainage. Results: We identified 35 IS and 35 non-IS out of 409 UE infection patients. Patients most commonly had a hematologic malignancy (34%) as their IS class, and the most frequent immunosuppressive medication was glucocorticoids (57%). IS patients were more likely to be older and less likely to have a history of drug abuse or hepatitis C virus infections. IS infections were more likely to have idiopathic mechanisms, more likely to involve deeper anatomy such as joints, bone, tendon sheath, or muscle/fascia, and less likely to present with leukocytosis. IS cultures more commonly exhibited atypical Mycoplasma or fungus. There was no difference between IS and non-IS patients regarding LOS or recurrent drainage. Conclusions: Mechanism and white blood cell count are less reliable markers of infection severity in IS patients. Physicians treating infections in IS patients should maintain a higher suspicion for deeper involved anatomy and atypical microbiology. Nonetheless, with careful inpatient management and closer surveillance, outcomes in IS patients can approach that of non-IS patients.

Aspects concerning patient adherence to anti-TNFα therapy in psoriasis: A decade of clinical experience

Non-adherence to psoriasis treatment has an important impact in controlling chronic disease evolution and the occurrence of systemic comorbidities. Biologic therapy represents a revolutionary treatment, many of the undesirable psychological and socio-economical consequences of conventional topical or systemic therapies being avoided. Nevertheless, the discontinuation of biological therapy may occur due to facts related to the patient, to the lack of good communication between the patient and the physician or to the adverse or paradoxical reactions. We studied the non-adherence reasons to anti-TNFα agents (Infliximab, Adalimumab, Etanercept) used for treating 84 cases with moderate-severe psoriasis. The results of our study over the past 10 years showed a 76.2% adherence rate, lowest in patients treated with Etanercept (70.9%). Relative to the anti-TNF agent used, the highest adherence rate was recorded in Adalimumab (80.8%), followed by Infliximab (76.5%) and Etanercept (70.9%). We have noticed differences between the rates of adhesion to therapy with different anti-TNFα agents, but with no statistical significance. The main adverse effects that occurred during anti-TNFα therapy were: local reaction to the drug, mild infectious events, allergic reactions, cardiotoxicity, alopecia areata, pancreatitis, eosinophilia, thrombocytopenia. Anti-TNF therapy was discontinued in one case of endocarditis, one case with tuberculous laryngitis and another one with polydiscitis (Adalimumab), a case of colon cancer and one of pregnancy (Etanercept) and one paradoxical reaction (Infliximab).

A Review of Switching Biologic Agents in the Treatment of Moderate-to-Severe Plaque Psoriasis

Psoriasis is an immune-mediated polygenic inherited skin disease. Many biologic agents have been approved for the treatment of moderate-to-severe plaque psoriasis. The most commonly utilized biologics include TNF-α antagonists (etanercept, infliximab, and adalimumab), IL-12/23P40 antagonist (ustekinumab), IL-23P19 antagonist (guselkumab), IL-17A antagonist (secukinumab and ixekizumab), and IL-17RA antagonist (brodalumab). However, some patients may fail to respond well to their first biologic agent. Reasons for failure include primary failure (lack of initial efficacy), secondary failure (loss of efficacy over time) or the development of adverse effects. For patients desiring maximum skin clearance and better quality of life, switching to a second biologic agent might be a worthwhile option. This review discusses recent clinical studies on switching therapies in treating psoriasis, and found that switching biologic agents can significantly improve outcomes for patients. Some clinical guidelines are also discussed. This research provides some advice on establishing individualized treatment regimens based on clinical needs and pharmacologic characteristics.

Granuloma Annulare: A Focused Review of Therapeutic Options

Granuloma annulare (GA) is a benign inflammatory disease associated with many conditions such as malignancy, trauma, thyroid disease, diabetes mellitus, and HIV infection. Common clinical subtypes include localized GA, generalized GA, subcutaneous GA, perforating GA, and patch GA. There exists an abundance of literature on GA, yet we know relatively little about its exact etiology and even less about its treatment. The paucity of conclusive data on effective treatment options is largely because the majority of published studies are limited to small case reports, case series, and retrospective studies. As such, there does not yet exist a gold standard of care to guide clinical management. Depending on the clinical subtype, the clinical prognosis for GA can vary. The localized variant generally self-resolves within 2 years without treatment, whereas the generalized form is more chronic and less responsive to treatment. This focused up-to-date review serves to summarize the latest therapeutic options available for GA.

The critical role of macrophages in the pathogenesis of hidradenitis suppurativa

INTRODUCTION

Hidradenitis suppurativa (HS) is a painful chronic inflammatory disease with a prevalence between 1 and 4% of general population. The pathogenesis of HS long eluded scientists, but growing evidence suggests that it is a consequence of inflammatory dysregulation.

FINDINGS

Recent studies suggest that dysregulated immune response to skin flora and overexpression of inflammatory cytokines leads to chronic skin inflammation seen in HS. Macrophages are the most numerous inflammatory cells found in HS infiltrates and release numerous pro-inflammatory cytokines such as IL-23, and IL-1β and TNF-α, exacerbating the inflammation and contributing to the pathogenesis of HS. Furthermore, in HS, there is dysregulated function of other immune players closely associated with macrophage function including: matrix metalloproteases (MMP) 2 and 9 overexpression, toll-like receptor upregulation, impaired Notch signalling, NLRP3 inflammasome upregulation, and dysregulated keratinocyte function. Lifestyle factors including obesity and smoking also contribute to macrophage dysfunction and correlate with HS incidence.

CONCLUSIONS

The overexpression of pro-inflammatory cytokines and subsequent efficacy of anti-cytokine biologic therapies highlights the importance of managing macrophage dysfunction. Future therapies should target key molecular drivers of macrophage dysfunction such as TLR2 and NLRP3 overexpression.

An Update on Medical Treatment Options for Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease characterized by recurrent inflammatory nodules mostly located in the armpits and groin. Over the years multiple treatments for HS have been proposed; however, to date a cure is still lacking. In this update we provide an overview of most drug treatments reported on for HS, where possible with their mode of action and side effects. In mild cases, clindamycin lotion or resorcinol cream have proven effective. Tetracyclines are a first-line systemic option in more widespread or severe cases, followed by the combination of clindamycin and rifampicin. However, the recurrence rate is high after discontinuation of clindamycin plus rifampicin combination therapy. Long-term treatment with retinoids, especially acitretin is feasible, although teratogenicity has to be taken into account in females of reproductive age. Multiple anti-inflammatory drugs have been suggested for HS, such as dapsone, fumarates or cyclosporine. However, their effectiveness in HS is based on small case series with varying results. If most common treatments have failed, biologics (e.g., infliximab or adalimumab) are the next step. Although not addressed in this review, surgical interventions are often needed to achieve remission.

Pharmacokinetic characteristics of therapeutic antibodies

Because of their high molecular weight and their highly hydrophilic character, therapeutic antibodies behave differently in terms of absorption, distribution and elimination compared to conventional drugs. Also, their pharmacokinetic profile varies significantly among individuals. After subcutaneous administration, antibodies are absorbed via the lymphatic system and become systemically bioavailable with some delay. The physicochemical properties of the molecules hinder their distribution from the bloodstream into the tissue. Elimination occurs by proteolysis in various organs (skin, muscle, liver), but mainly within the reticuloendothelial system. Also relevant is the elimination through target antigens (especially in the case of cell-bound target antigens) as well as a recycling process through binding to the neonatal Fc receptor that provides protection from lysosomal degradation. Depending on the immunogenicity of the therapeutic antibody and the individual immune response, neutralizing antibodies can develop. Pharmacokinetic conditions can be optimized by coadministration of, for example, methotrexate. Moreover, risk factors for the loss of immunological tolerance, such as on-demand therapy or elective switching of therapeutic antibodies, should be avoided.

The Role of Biologic Therapies in Dermatology

Biologic therapy has dramatically changed the way medicine, and specifically dermatology, is practiced today. The use of biologic agents in dermatology is evolving, with psoriasis being the most common indication for which biologics are used currently. However, several other dermatologic diseases seem to be responsive to biologic therapy, and continuing research and development efforts are elucidating the benefit-risk profiles of various biologic medications in these dermatologic conditions. Although biologic agents have revolutionized the management of dermatologic conditions, cost must also be considered when evaluating management options, especially compared with traditional agents. For example, the cost of 1 year of induction and maintenance treatment of psoriasis in 2014 was estimated to be $53,909 for ustekinumab, $46,395 for etanercept, and $39,041 for adalimumab. Nonetheless, because of their efficacy, the cost of a biologic may be offset by significant reductions in the number of hospital stays, reduction in use of other systemic therapies, and increased satisfaction by patients.32 Thus, understanding their mechanisms of action, labeled and off-label uses in dermatology, and common adverse effects helps to inform clinical decision making and improve patient outcomes.

Biologics in dermatology: adverse effects

Biologics are a group of drugs that precisely affect certain specific steps in the immune response and are an extremely useful group when used in an appropriate setting. However, their use can often be a double-edged sword. Careful patient selection and thorough knowledge of adverse effects is a key to their successful use in various disorders. The initial enthusiasm has gradually given way to a more cautious approach wherein a balance is sought between clinical usefulness and expected side effects. The adverse effects of the biologics most commonly used in dermatology have been carefully listed for ready reference. The plausible causes of the adverse reactions are succinctly outlined along with their incriminating factor(s). Besides, in brief, the attention has been focused on their management. The content should provide an essential didactic content for educating the practitioner.