Biological Treatments: 7 Skin Conditions Treated Effectively

Biological Treatments in Dermatology

Biological treatments, commonly referred to as biologics, represent a significant advancement in dermatological medicine. These innovative therapeutic agents are used to treat severe and refractory cases of inflammatory diseases, autoimmune diseases, and certain cancers affecting the skin. Unlike traditional systemic therapies that suppress the entire immune system broadly, biologics offer a more targeted and precise approach to interrupting underlying disease processes, often with fewer toxic side-effects.

What Are Biological Treatments?

In the strictest dictionary definition, a biological treatment or biologic drug would be any drug that is a biological product, extracted from plants, animals, fungi, or developed through bioengineering. However, in actual clinical use, the terms ‘biological treatment’ and ‘biologic’ predominantly refer to bioengineered monoclonal antibodies. These antibodies are laboratory-engineered against specific target antigens and are described as ‘monoclonal’, meaning they target a single, specific component of the immune system.

Biologics are protein-based drugs derived from living cells cultured in a laboratory. They work by modifying the host response to disease and include monoclonal antibodies and a variety of protein drugs which alter the activity of cytokines (such as interferons and interleukins), enzymes, and growth factors.

How Biological Treatments Work

Biological agents or treatments, also known as biologic therapies or biological response modifiers, are drugs derived from living material including human, plant, animal, or microorganism sources. They interfere with specific parts of the body’s immune system to treat and prevent immune-mediated inflammatory disorders and cancers.

A biological treatment binds a single target on an immune cell, such as an overactive interleukin (IL) or a surface protein that has contributed to the disease being treated. This targeted binding deactivates the specific immune component causing disease (for example, targeting IL-17, a major cause of psoriasis), thereby improving the skin condition while preserving overall immune function for other protective purposes.

Unlike general immunosuppressants that suppress the entire immune system indiscriminately, biological agents can fight more selectively and target only those specific chemicals involved in causing the particular skin disease. This selective targeting is one of the key advantages of biologic therapy over conventional systemic treatments.

Uses of Biological Treatments

Biological treatments are particularly effective for specific dermatological conditions:

• Psoriasis: Biologics can rapidly improve refractory psoriasis that has not responded to conventional therapies. Psoriasis involves a complex immune cascade where abnormally large numbers of T cells trigger the release of cytokines that cause inflammation, redness, itching, and flaky skin patches.
• Atopic eczema: Severe cases that fail conventional treatments often respond well to targeted biologic therapy.
• Urticaria: Refractory chronic urticaria can be effectively managed with biological agents.
• Autoimmune blistering diseases: Conditions such as pemphigus vulgaris respond to specific biologic treatments targeting involved immune pathways.
• Granulomatous skin diseases: Conditions like sarcoidosis benefit from off-label biologic use.
• Neutrophilic skin diseases: Pyoderma gangrenosum and related conditions show improvement with targeted biologic therapy.
• Hidradenitis suppurativa: TNF-α antagonists have demonstrated efficacy in treating this chronic inflammatory skin condition.

Nomenclature and Classification of Biologics

Biological treatments are classified based on their target antigen type. The nomenclature system includes designations for different classes of biologics:

Benefits of Biological Treatments

Biological treatments offer several significant advantages for dermatological management:

• Targeted approach: Biologics tweak only one part of the immune system rather than suppressing the entire immune system, allowing preservation of protective immune responses.
• Rapid efficacy: Biological treatments can often rapidly improve refractory skin conditions that have failed conventional therapies.
• Fewer toxic side-effects: Compared with conventional systemic therapies, biologics typically cause fewer systemic toxicities due to their targeted nature.
• Improved quality of life: Patients in biologic treatment groups demonstrate clinically meaningful improvements in health-related quality of life, as measured by validated assessment tools.
• Precision medicine: Recent advances have further elucidated the immunopathogenesis of skin diseases, enabling the development of biologics that target specific disease-causing mechanisms.

Disadvantages of Biological Treatments

Despite their benefits, biological treatments have several important limitations:

• High cost: Biological treatments are expensive, making them typically reserved for patients who have failed at least three other conventional treatments.
• Limited availability: Not all patients have access to these treatments due to healthcare system limitations and insurance coverage restrictions.
• Immune suppression risks: While more targeted than conventional immunosuppressants, biologics still suppress components of the immune system, increasing infection risk.
• Allergic reactions: Some patients may develop hypersensitivity or allergic reactions to the biologic agent.
• Restricted use in pregnancy: Biologics and small molecule medications are not routinely recommended during pregnancy because they have not been studied sufficiently in this population.

Side Effects and Risks

The side effects and risks of biological treatments relate primarily to suppression of components of the immune system and the induction of allergic reactions. A biological treatment binds a single target on an immune cell, deactivating that specific immune component, but this suppression can also diminish normal immune function against certain infections such as tuberculosis or candidiasis.

Patients receiving biological treatments require careful monitoring for:

• Opportunistic infections
• Reactivation of latent infections
• Hypersensitivity reactions
• Injection site reactions
• Systemic adverse effects related to immune modulation

Contraindications and Pregnancy Considerations

Biological treatments have important contraindications and special considerations for patients in reproductive years. Biologics and small molecule medications are not routinely recommended in pregnancy because they have not been studied sufficiently.

Pregnancy categories for common biologics include:

Category C designates drugs which, owing to their pharmacological effects, have caused or may be suspected of causing harmful effects on the human fetus or neonates without causing malformations.

Mechanisms of Action in Specific Conditions

Psoriasis

The pathogenesis of psoriasis involves a complex interaction between environmental factors and genetic predisposition. Inflammatory dermal dendritic cells produce IL-23, TNF, and nitric oxide radicals, which promote the activation of T cells and contribute to plaque formation. Studies have demonstrated discrete populations of Th1 and Th17 cells in psoriatic skin lesions, confirming the significance of T-cell mediated immune responses in the disease process. Many genes identified as conferring susceptibility to psoriasis belong to the IL-23-Th17 axis, the NF-kB pathway, and the epidermal differentiation complex.

Hidradenitis Suppurativa

Studies have highlighted components of immune dysregulation in hidradenitis suppurativa (HS) that support the use of biologic agents targeting TNF-α, IL-1β, and IL-10. The success of TNF-α antagonists in treating HS is documented in numerous case reports and clinical trials, with adalimumab at 40 mg per week showing efficacy and safety. Recent evidence has identified the potential importance of the IL-23/Th17 pathway in HS, with lesional skin samples demonstrating increased expression of IL-12 and IL-23 by dermal macrophages.

Pemphigus Vulgaris

Clinical improvement in pemphigus vulgaris has been observed with biologic treatment, paralleled by a sudden and prolonged reduction in circulating desmoglein-specific antibodies. Case reports have described the effectiveness of TNF-α antagonists including infliximab and etanercept in treating severe pemphigus, though formal clinical trials remain limited.

Novel Biologic Agents

Research continues to expand the arsenal of available biologics. Apremilast (CC-10004) is a novel biologic agent that specifically targets phosphodiesterase 4 (PD-4), an intracellular enzyme expressed predominantly in immune cells including dendritic cells, neutrophils, and monocytes, but also in keratinocytes.

Certolizumab pegol (CZP) is a PEGylated anti-TNF agent with a molecular structure different from other TNF antagonists. It is composed of a single Fab of human anti-TNF conjugated with polyethylene glycol, lacks an Fc portion, and its mechanism of action does not involve antibody-dependent cellular cytotoxicity, complement activation, or apoptosis in T cells or macrophages. Results demonstrate that 47% of patients in the CZP 400 mg group achieved a PASI 90 response at week 12, which is superior to that of adalimumab and etanercept.

Emerging research has also identified potential treatments targeting the angiogenesis pathway for treating chronic inflammatory conditions. “Valpha” is a chimeric “decoy receptor” which simultaneously binds vascular endothelial growth factor (VEGF-A) and TNF-α, demonstrating potential for future therapeutic applications.

Vaccinations and Biological Agents

Patients receiving biological treatments require special consideration regarding vaccinations. Because biologics suppress specific components of the immune system, live vaccines should generally be avoided during treatment. Consultation with healthcare providers is essential to determine appropriate vaccination schedules before initiating biologic therapy.

Monitoring During Biologic Therapy

Appropriate monitoring is essential for patients receiving biological treatments to detect potential adverse effects and ensure optimal therapeutic outcomes. Regular clinical assessments should evaluate:

• Skin disease response and improvement
• Development of infections
• Laboratory parameters including complete blood counts and liver function tests
• Tuberculosis screening and monitoring
• Adverse skin reactions at injection sites

The Future of Biological Treatments

The future of biological agents in dermatology is promising, with ongoing research continuing to identify new disease modulators as potential therapeutic targets. As the immunologic circuits in the pathogenesis of various skin diseases are further elucidated, new biologics targeting specific disease-causing mechanisms will continue to be developed. This advancement in precision medicine will likely expand treatment options and improve outcomes for patients with previously refractory skin conditions.

Frequently Asked Questions

Q: What is the difference between biologics and conventional systemic therapies?

A: Biologics target specific components of the immune system involved in disease, while conventional systemic therapies broadly suppress the entire immune system. This targeted approach in biologics typically results in fewer systemic toxicities and better preservation of protective immune responses.

Q: Who is eligible to receive biological treatments?

A: Biological treatments are typically reserved for patients with severe and refractory cases of inflammatory diseases, autoimmune diseases, and certain cancers who have failed at least three other conventional treatments. Specific eligibility criteria may vary based on individual patient factors and healthcare system guidelines.

Q: Are biologics safe during pregnancy?

A: Biologics are not routinely recommended during pregnancy because they have not been studied sufficiently in pregnant populations. Patients of reproductive age should discuss pregnancy planning with their healthcare providers before initiating biologic therapy.

Q: What infections are patients at increased risk for during biologic therapy?

A: Because biologics suppress specific components of the immune system, patients may have increased susceptibility to certain infections, particularly tuberculosis and candidiasis. Appropriate screening and monitoring are essential before and during treatment.

Q: How quickly do biologics work in treating skin conditions?

A: Biological treatments can often rapidly improve refractory skin conditions such as psoriasis, atopic eczema, and urticaria. However, the exact timeline varies depending on the specific condition and individual patient response.

Q: What is the cost of biological treatments?

A: Biological treatments are expensive, which is why they are typically reserved for patients who have exhausted other treatment options. Insurance coverage varies by policy and healthcare system, and patients should verify coverage before initiating therapy.

Similar Articles

Alarming Rise in Self-Harm in Young People

Alarming Rise in Self-Harm in Young People

Skin Signs Of Non-Accidental Injury: Expert Guide For Clinicians

Lichen Simplex Of The Scrotum: Diagnosis And Treatment

Labial Adhesion In Prepubertal Girls: What Parents Need To Know

Thrush In Men: 5 Signs, Causes, And Treatment Options

Author

medha deb

 

Medha Deb is an editor with a master's degree in Applied Linguistics from the University of Hyderabad. She believes that her qualification has helped her develop a deep understanding of language and its application in various contexts.

Read full bio of medha deb