Cosentyx (secukinumab) is a biologic medication used to treat chronic inflammatory conditions such as psoriasis, psoriatic arthritis, and ankylosing spondylitis. Since this drug modifies the immune system, patients frequently ask about its long-term safety, especially the risk of developing cancer. This article assesses the documented malignancy risk associated with Cosentyx, based on clinical trial data and current medical understanding.
How Cosentyx Works
Cosentyx is a monoclonal antibody, a protein-based drug designed to target a specific molecule in the body. Its therapeutic action involves selectively targeting and neutralizing Interleukin-17A (IL-17A). IL-17A is a naturally occurring cytokine that acts as a central messenger in the body’s inflammatory and immune responses.
In conditions like psoriasis, the immune system is overactive, producing excessive IL-17A, which drives inflammation and causes disease symptoms. By binding to IL-17A, Cosentyx prevents this cytokine from interacting with receptors on cells in the skin and joints. Blocking this interaction interrupts the inflammatory cycle, reducing symptoms of these chronic autoimmune disorders.
Clinical Evidence Regarding Malignancy Risk
Malignancy risk associated with immune-modulating drugs is extensively investigated through clinical trials and post-marketing surveillance. A large-scale integrated safety analysis of Cosentyx included data from patients with psoriasis, psoriatic arthritis, and ankylosing spondylitis, with up to five years of follow-up. Researchers use a standardized incidence ratio (SIR) to compare the observed rate of malignancy in the patient population to the expected rate in the general population.
This analysis concluded that the overall rate of malignancy in patients treated with Cosentyx was comparable to the general population (SIR of 0.99 across all indications). The exposure-adjusted incidence rate was reported as 0.85 per 100 patient-treatment years, supporting the conclusion that the risk of cancer is not significantly increased during five years of treatment.
Biologic studies closely monitor specific cancers, including non-melanoma skin cancer (NMSC) and lymphomas. In the Cosentyx safety analysis, over half of the reported malignancies were skin cancers, primarily NMSC. NMSC is common in the general population and prevalent in patients with long-standing psoriasis, regardless of treatment. Importantly, no lymphomas were reported in the study.
Post-marketing surveillance data, tracking outcomes from a larger number of patients, also showed a low cumulative incidence rate for malignancy. Although underlying inflammatory diseases may carry a slightly increased cancer risk (especially NMSC and lymphoma in severe psoriasis), Cosentyx did not compound this risk beyond expected rates. Observational studies have also shown no recurrence or progression of previous cancer in patients with a prior history of malignancy while on secukinumab.
Immune System Surveillance and IL-17A Inhibition
The immune system uses a complex, multi-layered process known as “immune surveillance” to identify and destroy nascent cancerous cells before they develop into detectable disease. Since Cosentyx modulates the immune system, researchers must consider how blocking IL-17A affects this protective surveillance. IL-17A’s role in cancer is complex; it can be both pro-tumorigenic and anti-tumorigenic depending on the context.
Pro-Tumorigenic Role
In some models, IL-17A promotes tumor growth by stimulating inflammation and creating a favorable environment for cancer cells. Blocking IL-17A with Cosentyx could theoretically have an anti-tumor effect in these cases.
Anti-Tumorigenic Role
Conversely, IL-17A is involved in activating immune cells, such as T cells, which are crucial for the anti-cancer response. Neutralizing this cytokine raises a theoretical concern that the body’s defense against a developing tumor might be compromised.
However, the available long-term clinical data from patients taking Cosentyx have not indicated a widespread disruption of overall immune surveillance leading to an increased risk of common malignancies. The drug’s highly selective mechanism likely explains why it does not significantly interfere with the broad anti-tumor functions of the immune system.
Required Medical Monitoring for Patients
Patients considering or currently using Cosentyx require proactive medical monitoring to ensure safety.
Pre-Treatment Screening
Before starting treatment, a physician must screen the patient for latent infections, particularly tuberculosis (TB). If latent TB is detected, it must be treated before Cosentyx is administered, as the drug may reduce the immune system’s ability to keep the infection dormant. Patients must also discuss their complete medical history, including any previous cancer diagnosis, with their prescribing physician.
Ongoing Monitoring
Due to the higher baseline risk of non-melanoma skin cancer in patients with inflammatory skin conditions, regular dermatological screenings are highly recommended. Patients should have an annual skin check and immediately report any new or changing skin lesions to their healthcare provider.
Throughout the course of treatment, patients must remain vigilant for signs of infection, such as fever, persistent cough, or unusual fatigue, and report them promptly. The prescribing physician will determine the need for other ongoing monitoring, which may include periodic blood tests to check for changes like neutropenia, a reduction in a type of white blood cell. Open communication with the healthcare team is essential to manage potential risks and ensure the continued safe use of the medication.