Main Research Findings

Abrocitinib, a Janus kinase-1 inhibitor, has been approved for the treatment of moderate-to-severe atopic dermatitis in adults in Europe since 2021. 4 Multiple phase three studies have demonstrated its efficacy, good tolerance, and a safe profile with generally mild side effects, even from the initial stages of oral administration. 4 The low frequency of side effects and the advantage of oral administration make abrocitinib a valuable addition to the treatment of moderate-to-severe atopic dermatitis.

Reasons for Side Effects

Abrocitinib's side effects stem from its inhibition of the JAK1 enzyme, which plays a crucial role in various cytokine signaling pathways involved in immune cell activation and inflammation. By blocking JAK1, abrocitinib disrupts these pathways, suppressing the inflammatory response in atopic dermatitis. However, JAK1 is also involved in the function of other cells, not just immune cells. Thus, inhibiting JAK1 can affect other cell functions besides suppressing immune cell activation, potentially leading to side effects. 5

Common Side Effects

Thrombocytopenia

A self-limited, dose-related decrease in platelet counts has been consistently observed in clinical trials, but without clinical repercussion. 3 Thrombocytopenia, a decrease in platelet count, is a potential side effect reported in some studies. 8 Platelets are essential for blood clotting, so a reduction can increase the risk of bleeding. 3 The severity of thrombocytopenia may vary depending on the dose of abrocitinib and usually resolves upon discontinuation of the medication. 3

Infections

Abrocitinib, as an immunosuppressant, can potentially increase the risk of infections. 5 The risk of infection is influenced by factors such as the dose and duration of treatment, as well as the individual's immune status. It's crucial to be vigilant for signs of infection and consult a doctor promptly if any arise.

Liver Dysfunction

Abrocitinib can potentially affect liver function. 5 Regular monitoring of liver function through tests is essential during treatment. If abnormalities are detected, discontinuation of abrocitinib may be necessary.

Side Effect Management

Thrombocytopenia

To mitigate the risk of thrombocytopenia, a blood test to check platelet count before starting abrocitinib is recommended. 3 During treatment, regular blood tests are crucial to monitor platelet levels. 3 If the platelet count falls, abrocitinib may need to be discontinued or the dosage adjusted.

Infections

To minimize the risk of infections, practicing good hygiene, including handwashing and gargling, is essential during abrocitinib treatment. 5 Individuals with a higher susceptibility to infections, or those experiencing an infection, should consult a doctor promptly.

Liver Dysfunction

Regular liver function tests are vital during abrocitinib treatment to reduce the risk of liver dysfunction. 5 If abnormalities are detected in liver function tests, abrocitinib may need to be discontinued or the dosage adjusted.

Study Comparisons

Commonalities in Studies

Consistent findings across multiple studies indicate that abrocitinib effectively improves atopic dermatitis symptoms and reduces itching. 4 , 9 , 5 , 10 , 8 , 7 , 6 , 3 Abrocitinib is generally well-tolerated, with few reports of serious side effects. 4 , 8 , 7 , 3

Differences in Studies

While research consistently demonstrates abrocitinib's effectiveness, some variations exist in terms of efficacy and safety among studies. Factors such as the abrocitinib dosage and treatment duration, patient age and severity of atopic dermatitis, and concomitant medications can influence these outcomes. 4 , 9 , 5 , 10 , 8 , 7 , 6 , 3 Side effect profiles can also differ across studies. For instance, some studies report thrombocytopenia while others do not. 8 , 3 These variations may be attributed to differences in research methodologies and patient characteristics.

Important Considerations for Real-World Application

While abrocitinib shows promise for treating moderate to severe atopic dermatitis, it's crucial to acknowledge the potential for side effects. 4 , 9 , 5 , 10 , 8 , 7 , 6 , 3 Before beginning abrocitinib treatment, a consultation with a doctor is essential to determine the most suitable treatment approach for your individual needs. Regular follow-up appointments with your doctor are also vital to monitor for any potential side effects while on abrocitinib.

Limitations of Current Research

Current research on abrocitinib's efficacy and safety remains limited in terms of both the number of studies and the availability of long-term data. 5 Moreover, the majority of studies evaluating abrocitinib are conducted by pharmaceutical companies, raising the potential for bias in research findings. Furthermore, a limited number of studies directly compare abrocitinib with other atopic dermatitis treatments, making it difficult to fully assess its relative efficacy and safety.

Future Research Directions

Future research should focus on evaluating the long-term efficacy and safety of abrocitinib. 5 Comparative studies against other atopic dermatitis treatments are also needed. Additionally, research into the mechanisms behind abrocitinib's side effects is crucial. These research efforts can contribute to safer and more effective use of abrocitinib in the future.

Conclusion

Abrocitinib has emerged as a promising treatment option for moderate to severe atopic dermatitis, demonstrating efficacy and a favorable safety profile in multiple clinical trials. 4 , 9 , 5 , 10 , 8 , 7 , 6 , 3 While abrocitinib offers significant benefits in managing atopic dermatitis symptoms, it's essential to be aware of potential side effects. A doctor's consultation is paramount to determine the most appropriate treatment plan. Regular monitoring for side effects while on abrocitinib is crucial. Continued research is vital to fully understand abrocitinib's long-term effects and to develop safer and more effective therapeutic approaches.