2018 saw the new launch of digarelix in China, the launch of 2 new drugs in the US – apalutamide and micronized abiraterone acetate – and the expansion of 2 drugs – -abiraterone and enzalutamide. They are listed below:
(Note: GnRH, gonadotropin-releasing hormone, is secreted by the brain and it promotes the production of androgens)
How do these new drugs work? What kind of patients are they for? We invited leading experts in the field of prostate cancer in China – Professor He Zhisong and Deputy Chief Physician Yu Wei of the Department of Urology at Peking University First Hospital – to break it down for you.
What patients can use it?
Endocrine therapy for patients with intermediate to advanced disease: digarelix
About 90% of prostate cancer cases are associated with androgen stimulation, so most patients with intermediate to advanced disease receive androgen-deprivation therapy (ADT), which involves taking medication to suppress androgen (testosterone) production, or removing the testicles. The Degarelix can directly antagonize the effects of GnRH and reduce the level of androgens in the body.
Non-metastatic desmoplastic-resistant prostate cancer: apalutamide and enzalutamide
After a period of endocrine therapy, almost all patients experience treatment “failure,” which is called “Castration Resistant Prostate Cancer (CRPC). This is called “Castration Resistant Prostate Cancer (CRPC)”, which means that the disease progresses despite low testosterone levels. This is called “Castration Resistant Prostate Cancer (CRPC),” which means that the disease progresses despite low testosterone levels. There are two types of CRPC: those that have not metastasized distantly, called “non-metastatic” CRPC, and those that will eventually progress to “metastatic” CRPC if not well controlled.
In the past, the lack of standard treatment options for non-metastatic CRPC, which was mainly second-line endocrine therapy, has been broken by apalutamide, a new drug approved in 2018. It blocks androgen receptors with potency and precision. Studies have shown that patients with non-metastatic CRPC using this drug have been free of distant metastases or death for up to 40.5 months, with a 72% reduction in risk. Enzalutamide offers another option for this group of patients. In the study, it resulted in a median metastasis-free survival (MFS) time of 36.6 months in these patients, with a 71% reduction in risk.
Metastatic desmoresistant prostate cancer: micronized abiraterone acetate and abiraterone
For metastatic CRPC, in 2018 the FDA approved a new drug from an Indian pharmaceutical company for marketing – micronized abiraterone acetate. It was found to combine with prednisolone in first-line treatment of metastatic CRPC, with a median patient survival of more than 30 months; even when used after chemotherapy failure, the median patient survival was more than 15 months.
What is better about the new drug?
The long-term efficacy of degarelix in controlling tumors is similar to that of the drugs commonly used today, and for a similar population. In patients with extensive bone metastases, degarelix reduces the risk of fractures early in treatment. Furthermore, the currently used GnRH agonists, which are associated with a transient increase in androgens at the start of dosing, do not, and therefore do not require coadministration with drugs that block androgen action.
Apalutamide and enzalutamide were effective in reducing cancer recurrence, giving patients a longer time to disease control and also reducing the risk of death.
Particulate abiraterone acetate is actually a super-particulate formulation of the “old” abiraterone, but it is more easily absorbed than the old drug. So the dose is half that of abiraterone without “halving” its effectiveness, and it’s easier for patients to take it without being influenced by diet.
Can Chinese patients use these new drugs?
Can Chinese patients use these new drugs?
Neither apalutamide nor enzalutamide is currently available in China, and domestic patients will have to wait a while. Patients with metastasis-free CRPC in China can continue with second-line endocrine therapy (such as hormones) or they can use abiraterone, which has been shown in some studies to also delay the time to metastasis in patients with metastasis-free CRPC.
For the vast majority of patients with metastatic CRPC in China today, abiraterone would meet the clinical need, but for patients who cannot tolerate fasting, consider using micronized abiraterone acetate.
If you want to learn more about new drugs coming to market in 2018, click to read