Which treatment is more effective, enzalutamide/enzalutamide (encotan) or abiraterone?

In the treatment of prostate cancer, especially castration-resistant prostate cancer (CRPC), Enzalutamide and Abiraterone are two commonly used drugs. They each inhibit the androgen signaling pathway through different mechanisms, thereby inhibiting tumor growth. Although both drugs are FDA-approved for the treatment of castration-resistant prostate cancer, their therapeutic efficacy, mode of use, and side effects differ, so which drug is better remains a topic of discussion in clinical practice.

1. Differences in treatment mechanisms

Enzalutamide is an androgen receptor (AR) inhibitor that inhibits the transcriptional activity of the androgen receptor by directly binding to the androgen receptor and preventing its binding to androgens. It not only inhibits the transcriptional effect of the receptor, but also prevents the receptor from entering the cell nucleus to function, thereby reducing the dependence of cancer cells on androgens.

Abiraterone is a selectiveCYP17A1 inhibitor that acts on the androgen synthesis pathway in adrenal and prostate tumors, especially by inhibiting the CYP17A1 enzyme, thereby reducing the level of androgens in the body. Androgens are a key factor in the proliferation and growth of prostate cancer cells. Therefore, by reducing the synthesis of androgens in the body, abiraterone can effectively inhibit the growth of cancer cells.

2. Comparison of clinical efficacy

Enzalutamide and abiraterone have both been shown to be effective against castration-resistant prostate cancer in multiple clinical trials. In these patients, prostate cancer growth is no longer dependent on low levels of endogenous testosterone but rather on abnormal activation of androgen receptors or the persistence of exogenous androgens. Therefore, these two drugs inhibit this abnormal androgen signaling through different mechanisms, thereby inhibiting tumor progression.

Based on key clinical research data, enzalutamide is considered slightly more effective than abiraterone in some studies. For example, in the pivotal AFFIRM study, enzalutamide significantly prolonged overall survival (OS) and progression-free survival (PFS) compared with placebo in patients with castration-resistant prostate cancer. In addition, enzalutamide can significantly improve patients' quality of life, especially in improving pain and life functions.

Abiraterone also has significant efficacy, especially in In the COU-AA-301 study, abiraterone significantly prolonged overall survival (OS) and reduced progression of prostate-specific antigen (PSA) levels in patients with castration-resistant prostate cancer. Although its efficacy is widely recognized, in certain patient groups, abiraterone may be more likely to cause side effects, especially adrenocortical suppression (such as hyponatremia, hyperkalemia, etc.).

3. Differences in side effects

There are certain differences in the side effects spectrum between enzalutamide and abiraterone. Common side effects of enzalutamide include fatigue, dizziness, hot flashes, joint pain, and effects on the central nervous system (such as seizures). Of particular note is that enzalutamide may cause epileptic seizures, especially at high doses, and therefore special vigilance is required during clinical use.

The side effects of abiraterone are mainly systemic effects related to its inhibition of androgen synthesis, such as hyperglycemia, hypertension, elevated liver enzymes, and hyponatremia. Because abiraterone inhibits multiple pathways of androgen synthesis, it may cause adrenocortical dysfunction and even require corticosteroid supplementation in some cases.

Overall, while both are useful in the treatment of castration-resistant prostate cancer, abiraterone may be associated with side effects that may lead to treatment discontinuation in some patients. Especially in patients with cardiovascular risk or liver function problems, the use of abiraterone may require additional caution and monitoring.

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