HQ Team
June 21, 2023: The USFDA has approved Pfizer Inc’s oral Talzenna drug in combination with Xtandi to treat advanced prostate cancer in adult patients, according to a statement.
The approval was based on the “statistically significant and clinically meaningful” radiographic progression-free trial on patients during the last stage of the experiment.
The results demonstrated a 55% reduction in the risk of disease progression or death in patients with metastatic castration-resistant prostate cancer (mCRPC).
Metastatic prostate cancer spreads beyond the prostate gland and progresses despite medical or surgical treatment to lower testosterone.
Metastatic cancer
About 10-20% of patients with prostate cancer become metastatic within 5-7 years of diagnosis. In the US, in 2020, approximately 60-90 thousand of the three million cases were mCRPC.
The homologous recombination repair (HRR) gene mutations were found in about 25% of tumors in men with the disease and have been associated with aggressive disease and poor prognosis.
The analysis of the HRR genes in individuals with an active diagnosis of prostate cancer may assist in identifying potential therapeutic options and inform risks for other cancers.
“Despite treatment advancement in metastatic castration-resistant prostate cancer, the disease can progress quickly, and many patients may only receive one line of therapy,” said Neeraj Agarwal, global lead investigator for the trials.
Reduce progression, death
“Therefore, new first-line treatment options are needed to reduce the risk of disease progression or death. For patients with mCRPC harboring HRR genetic alterations, outcomes are even worse,” he said.
The FDA’s approval of the talazoparib (Talzenna) and enzalutamide (Xtandi) combination was based on the findings from the experimental study, he said. “It represents a treatment option deserving of excitement and attention.”
The final trial data will be reported once the “predefined number of survival events has been reached” and, if appropriate, may be used to support a potential regulatory filing to benefit broader patient populations.
The final overall survival data are expected in 2024, according to the statement.
Adverse reactions
Serious adverse reactions occurred in 30% of patients treated with the combination drug. More than two percent had reactions such as anemia, nine percent, and fracture, three percent.
The drug was discontinued in 10% of the patients.
The combination drug’s safety “was generally consistent with the known safety profile of each medicine.”
A marketing authorization application for the Talzenna and Xtandi combination has been accepted for review by the European Medicines Agency. Pfizer has also shared data with other regulatory agencies to support regulatory filings.
Talzenna has been approved in more than 70 countries, including the US, as a once-daily monotherapy for the treatment of adult patients with breast cancer.
