New Hope for Patients With Metastatic Prostate Cancer

Highlights:

• Precision therapy can now treat advanced metastatic prostate cancer
• In 2019, there were about 174,650 new cases of prostate cancer in the U.S and 31,620 disease-related deaths
• Olaparib is a precision drug that inhibits PARP protein, which helps cancer cells repair themselves
• Treating with Olaparib delays disease progression and time to pain progression, and prolongs survival of patients with advanced, metastatic prostate cancer

Prostate cancer can now be treated with precision therapy and for the first time, it has been treated based on the genetic makeup of the cancer. This prostate cancer therapy prolongs the life of an individual and delays disease progression, reveals a recent large Phase 3 clinical trial at Northwestern Medicine. The PROfound trial treated metastatic prostate cancer that failed to respond to other treatments including hormone therapy.

Dr. Maha Hussain, Northwestern principal co-investigator, said: “This marks a significant advance for prostate cancer treatment, which has lagged behind other common cancers with regard to precision therapy, now the standard of care in breast, ovarian and lung cancers. Treatments for metastatic, hormone-resistant prostate cancer have continued to use 'one-size-fits-all' approaches, overlooking the genetic make-up of the tumor."

The results of the trial were presented during the 2019 European Society of Medical Oncology in Barcelona at the Presidential Symposium.

Testing Efficacy of Olaparib in Metastatic Prostate Cancer

• The study team chose patients with known genetic alterations that help cells to repair DNA damage. The most common mutations are the BRACA 1, BRACA 2 and ATM genes as well as many others
• Patients with these genetic alterations were randomly assigned to receive either olaparib, which has been used in other solid tumors (ovarian, breast and pancreatic) or standard hormone therapy with either enzalutamide or abiraterone and prednisone
• Olaparib inhibits PARP protein that helps damaged cells repair themselves. Certain cancer cells depend on PARP protein to repair DNA damage. If PARP is prevented from repairing DNA damage, the tumor cells are destroyed
• Patients who were given olaparib had a marked extension of progression-free phase before the disease grew and spread
• The average duration before disease progression occurred was more than double i.e., 7.4 months for the olaparib-treated patients in comparison to 3.6 months in the group of patients given standard hormone therapy of enzalutamide or abiraterone and prednisone
• At six months following therapy, 60% of the men receiving olaparib showed no disease progression in comparison to 23% in the control groups
• After 12 months, nearly thrice the number of patients on olaparib remained free of disease progression (28% in comparison to 9% in the control groups)
• Patients in the control group received standard hormone therapy for prostate cancer. When the men in the control groups showed the progression of disease, they were started on olaparib
• The benefit of olaparib treatment was across the board, irrespective of patient’s cancer location, prior treatment, or site of metastatic disease (bone, liver or lymph nodes), age of the patient and the patient's PSA (prostate-specific antigen)levels
• Patients on olaparib had a longer pain-free period before the disease progressed to bone
• The percentage of patients still alive at six, 12 and 18 months is higher in patients who received olaparib
• One-year survival was 73% for the olaparib group compared to 56.94% for the control group; at 18 months, survival of the olaparib group was 56.3% compared to 42.13% in the control group
• Similar trends were found in another group of patients (cohort B), having a different set of genetic alternations, not as powerful as those in cohort A

Thus, the findings of the study suggest that olaparib prolongs survival as well as extends time period before progression of disease occurs in prostate cancer patients.

Prostate Cancer in Brief

• Prostate cancer is the most common type of cancer in men
• Men with prostate cancer present with an enlarged prostate, difficulty in passing urine, urinary retention and other symptoms.
• Prostatic antigen levels will be a markedly elevated and physical examination and imaging investigations reveal enlarged prostate with abnormal morphology
• Imaging investigations also help to stage the disease clinically. Treatment options include surgery, radiation, chemotherapy and hormone therapy

According to the National Cancer Institute, there are about 174,650 new cases of prostate cancer in the U.S., and 31,620 disease-related deaths in 2019. Figures from 2016 estimate that 3,100,000 men are living with prostate cancer in the U.S.

In summary, olaparib may offer new hope to patients with prostate cancer and their families by extending survival as well as delaying further progression of disease.

Reference:

1. First Prostate Cancer Therapy to Target Genes Delays Cancer Progression - (https://news.feinberg.northwestern.edu/2019/09/first-prostate-cancer-therapy-to-target-genes-delays-cancer-progression/)

Source-Medindia