What are Biologics?

In dermatology, biological treatments, or biologics, refer to monoclonal antibodies— laboratory-created proteins that target foreign substances to evoke an immune response, known as antigens. Monoclonal antibodies are exact copies of one antibody, so they can only bind to a specific antigen.^1,2 Since biologics only target one part of the immune system, instead of suppressing the entire immune system,^2,3 they have less risk of causing organ damage than other medications.⁴ Targets of biologics in dermatological diseases include interleukins (ILs), tumor necrosis factor (TNF)-alpha, CD20, and immunoglobulin E (IgE).^3,5 

Biologics are typically prescribed to patients with moderate-to-severe disease; disease severity is determined through a combination of factors, including how much of the body surface area is affected, location of affected skin, and impact on quality of life.^3,6 Biologics are administered via intravenous (IV) infusion in a healthcare setting or self-injection at home.^3,4,6 

Currently, biologics are mainly used in the treatment of psoriasis. Eleven biologics are approved by the United States (US) Food and Drug Administration (FDA) for the treatment of psoriasis,⁴ and these include IL-12/23, IL-17, IL-23, and TNF-alpha inhibitors.³ Two biologics are FDA-approved for atopic dermatitis (AD),⁶ and one each are approved for hidradenitis suppurativa (HS), chronic spontaneous urticaria (CSU), and pemphigus vulgaris (PV).⁵ Additionally, biologics can be used off-label for the treatment of various skin conditions, particularly in the case of rare diseases.⁷ 

Benefits of biologics

Most individuals with psoriasis who receive biologics have clearer skin within three to four months, with some experiencing symptom improvement as early as one week after treatment.³ Various clinical trials have shown that after one year of biologic treatment, about 80 to 90 percent of patients with psoriasis achieved a 90-percent reduction in Psoriasis Area and Severity Index (PASI90) scores, indicating almost clear skin, and about half achieved PASI100,⁸ indicating complete resolution of psoriatic lesions. In addition to improving psoriasis symptoms, biologic therapy has been associated with decreased risk of developing related health risks, such as cardiovascular disease, Crohn’s disease,^3,8 and depressive symptoms.⁸ 

Patients with AD can experience symptom improvement after four weeks of biologic treatment.^6,9 In addition to skin clearance, biologics might also decrease itching and improve sleep and quality of life,¹⁰ and clinical trials showed that treatment benefits were maintained for one year.^9,10 

Weekly treatment with adalimumab has demonstrated clinical efficacy in patients with HS.^11,12 Long-term data showed that efficacy was maintained through 168 weeks.¹¹ Additionally, weekly adalimumab treatment was associated with improved quality of life.¹² 

In individuals with CSU, omalizumab response can occur up to six weeks after the initial treatment for fast responders three months after the first treatment for slow responders. Patients who do not experience treatment response after six months are considered nonresponders. Real-world studies have indicated that about 80 percent of patients with CSU experienced disease improvement with omalizumab treatment.¹³

Rituximab plus corticosteroid treatment is considered first-line treatment for moderate-to-severe PV.¹⁴ Studies have shown that most patients treated with rituximab achieved remission after 3 to 4 months of treatment,^14,15 and more patients sustained complete remission for one year with rituximab than mycophenolate mofetil (40% vs. 10%).¹⁵ However, many patients still experience relapse with rituximab treatment, and further research must be conducted to determine optimal dosing.^14,15

Risks of biologics

Biologic treatment is administered continuously, as risk of disease recurrence and treatment failure are higher when treatment is interrupted.^4,5 Even with continuous treatment, however, biologics might lose efficacy over time,^3,5,6 and the higher the number of biologics an individual has previously taken, the higher the risk of treatment failure with another biologic.⁵

As with any medical treatment, biologic treatment carries a risk of side effects. Although biologics do not fully suppress the immune system, they still target elements of the immune system, thereby increasing the risk of certain infections; as such, patients must be screened for infections before initiating biologic therapy.^2–4 Biologics might induce allergic reactions.^2,3 Injection site reactions are a common side effect of most biologics.^3,4,10,15 Each drug has a risk of specific side effects as well. For example, common side effects of dupliumab include pink eye, dry/itchy eyes, and inflammation of the cornea or eyelids, and common side effects of tralokinumab-Idrm include elevated eosinophil levels, upper respiratory tract infection, and pink eye.¹⁰ Talk to your doctor about drug-specific side effects if you are considering biologic treatment. 

Bottom Line

Biologics are safe, effective treatments for multiple skin conditions. Consult with a physician if you think biologics are right for you.

Sources

1. Cleveland Clinic. Monoclonal antibodies. Reviewed 16 Nov 2021. https://my.clevelandclinic.org/health/treatments/22246-monoclonal-antibodies. Accessed 11 Jul 2023.
2. Luther E. Biological treatments. DermNet. https://dermnetnz.org/topics/biologics. Accessed 11 Jul 2023.
3. Bruce DF, Etier A. The consumer’s guide to biologics for psoriasis. Everyday Health. Reviewed 14 Mar 2023. https://www.everydayhealth.com/psoriasis/the-consumers-guide-to-biologics-for-psoriasis/. Accessed 11 Jul 2023.
4. American Academy of Dermatology. Psoriasis treatment: biologics. Updated 8 Jun 2022. https://www.aad.org/public/diseases/psoriasis/treatment/medications/biologics. Accessed 11 Jul 2023.
5. Kahlenberg JM, Billi AC, Eyerich K, Gudjonsson JE. Biologics in the treatment of skin and rheumatologic diseases. J Allergy Clin Immunol. 2020;145(4):1138–1141. 
6. Masters M. The consumer’s guide to biologics for atopic dermatitis. Everyday Health. Reviewed 2 Mar 2023. https://www.everydayhealth.com/eczema/the-consumers-guide-to-biologics-for-atopic-dermatitis/. Accessed 11 Jul 2023.
7. Mitra D, Chopra A, Saraswat N, et al. Biologics in dermatology: off-label indications. Indian Dermatol Online J. 2020;11(3):319–327.
8. Kamata M, Tada Y. Efficacy and safety of biologics for psoriasis and psoriatic arthritis and their impact on comorbidities: a literature review. Int J Mol Sci. 2020;21(5):1690. 
9. Ratchataswan T, Banzon TM, Thyssen JP, et al. Biologics for treatment of atopic dermatitis: current status and future prospect. J Allergy Clin Immunol Pract. 2021;9(3):1053–1065.
10. Pietrangelo A. Targeted treatments for eczema: everything you need to know. Healthline. 13 Apr 2022. https://www.healthline.com/health/eczema/biologics-for-eczema#1. Accessed 11 Jul 2023.
11. Aarts P, Dudink K, Vossen ARJV, et al. Clinical implementation of biologics and small molecules in the treatment of hidradenitis suppurativa. Drugs. 2021;81(12):1397–1410.
12. Lu JW, Huang YW, Chen TL. Efficacy and safety of adalimumab in hidradenitis suppurativa: a systematic review and meta-analysis of randomized controlled trials. Medicine (Baltimore). 2021;100(22):e26190. 
13. Ensina LF. Omalizumab in chronic spontaneous urticaria. World Allergy Organization. 7 Jun 2018. https://www.worldallergy.org/ask-the-expert/questions/omalizumab-in-chronic-spontaneous-urticaria. Accessed 11 Jul 2023.
14. Heymann WR. Progress in pemphigus: solidifying rituximab’s role. American Academy of Dermatology. 7 Jul 2021. https://www.aad.org/dw/dw-insights-and-inquiries/archive/2021/progress-pemphigus-solidifying-rituximab-role. Accessed 11 Jul 2023.
15. Bishnoi A, De D, Handa S, Mahajan R. Biologics in autoimmune bullous diseases: current scenario. Indian J Dermatol Venereol Leprol. 2021;87:611–620.