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The American Society of Clinical Oncology (ASCO) hosts one of the largest medical conferences in the world, with more than 42,000 attendees in 2019. This is where researchers present early work that eventually translates into breakthroughs in new drugs and standard of care improvements for patients.

Undaunted by the COVID-19 pandemic, researchers and clinicians from around the world in academia and industry tuned in online to view talks and abstracts at the Virtual Scientific Program at the end of May. The collaboration will continue over the next weeks and months.

Here are some highlights from the prostate cancer presentations. Key themes included PSMA imaging and therapeutics as well as final data from 3 clinical trials in non-metastatic castration-resistant prostate cancer (nmCRPC).

PSMA Imaging and Therapeutics

First, a quick primer on PSMA, short for Prostate-Specific Membrane Antigen, a protein that is found in relatively larger amounts on the surface of prostate cancer cells. The strategy is to first target prostate cancer cells by creating a small molecule that will bind to the PSMA on their surface. Another compound is attached to this “target” molecule that either 1) enables imaging of the cancer cells or 2) delivers radiation directly to the cells, killing them.

• Treatment using PSMA: PCF-funded researcher Prof. Michael Hofman presented initial results of a clinical trial in which a PSMA therapeutic agent (Lu-PSMA) showed greater PSA response rate vs the control (the FDA-approved drug cabazitaxel) in patients with metastatic castration-resistant prostate cancer (mCRPC). Read more about this trial
• Imaging using PSMA in men with occult recurrence: Conventional imaging methods can be inadequate to characterize biochemically-recurrent prostate cancer. PCF-funded researcher Dr. Michael Morris and team used a new imaging agent that binds to PSMA called ¹⁸F-DCFPyL, leading to changed management plans in many of the subjects.
• Imaging using PSMA in men to identify lymph node metastases: A PCF-funded study led by Dr. Thomas Hope found that 68Ga-PSMA-11 PET scanning detected lymph node metastases with high specificity – if the scan was positive, it was very likely that cancer was present. This may help doctors better understand the extent of disease before surgery.

What this could mean for patients: a more accurate way to find where prostate cancer may have spread in the body, allowing for better treatment planning, and targeting therapies directly at the cancer cells.

Final data on 3 trials in men with nmCRPC

Overall survival data on three large randomized, placebo-controlled phase 3 clinical trials of 2nd-generation anti-androgens were presented. What this means for patients: enzalutamide, apalutamide, and darolutamide remain excellent treatment options for men with nmCRPC.

More findings

• A PCF-funded study showed promise of a “liquid biopsy” to predict response and monitor treatment. Researchers analyzed the fragments of cancer DNA (ctDNA) in the bloodstream of patients with advanced or metastatic prostate cancer enrolled in a clinical trial. They found that the amount of ctDNA correlated with response to treatment, potentially allowing a minimally-invasive way of getting information about a patient’s cancer burden. What this could mean for patients: a less invasive way to track response to cancer treatment.
• The CARD trial had previously shown that cabazitaxel is a new standard of care for third-line treatment in patients mCRPC who have progressive disease after docetaxel and progressed within one year or less of abiraterone or enzalutamide and who are fit enough to tolerate chemotherapy. Overall survival results were presented that confirmed these findings. What this means for patients: guidance for the next choice of therapy in men with very aggressive disease.
• Bipolar androgentherapy is an experimental treatment approach in which men are rapidly cycled between extremely high and extremely low (castrate) levels of testosterone. PCF-funded researcher Dr. Emmanuel Antonarakis was part of a team that demonstrated that this approach is safe and has efficacy in men with mCRPC, and actually restores some response to anti-androgens. What this could mean for patients: a new treatment option for men with mCRPC.
• in 2015, the PCF-SU2C International Prostate Cancer Dream Team published a landmark study that paved the way for the recent approval of PARP inhibitors in mCRPC. Now, the PCF-funded West Coast Prostate Cancer Dream Team has characterized the “epigenetic landscape” of this disease – chemicals that bind to DNA and play a role in regulating which genes are activated. The study identified 2 subtypes of prostate cancer; this may lead to additional precision medicine targets. What this could mean for patients: more approaches to treating men based on their particular kind of prostate cancer.
• High-risk localized prostate cancer can recur despite treatment. A PCF-funded study led by Dr. Rana McKay, along with Dr. Mary Ellen Taplin, found that “intense” ADT (such as apalutamide + abiraterone + leuprolide + prednisone) before prostatectomy led to favorable pathology results. The team will continue to follow patients to understand the effect of this therapy on recurrence rates. What this could mean for patients: a certain ADT regimen before surgery may improve outcomes (though more data are needed to confirm).
• HEROS among us: the large phase 3 HERO trial that demonstrated that a new oral form of ADT, relugolix, is superior to the commonly used agent leuprolide on some metrics. What this could mean for patients: an additional option for men on ADT.