When a patient is diagnosed with prostate cancer a doctor might predict the success of the treatment based on clinical trials. While the information clinical trials provide is extremely valuable, “it is not precision medicine,” says Harshraj Leuva, M.B.B.S.
Dr. Harshraj Leuva received a Conquer Cancer Young Investigator Award (YIA) in 2021 to optimize drug development for United States Veterans with prostate cancer. Prostate cancer is the most frequently diagnosed form of cancer among U.S. Veterans. In the U.S., it is the second leading cause of cancer death in men.
“We are developing a surrogate marker to assess treatment effectiveness in prostate cancer. This is a mathematical model which provides tumor growth rates using Prostate Specific Antigen (PSA) values while the patient is on any medication,” explains Dr. Leuva.
PSA is the most common blood test done routinely in a physician's office to monitor prostate cancer. Dr. Leuva's model will provide more individualized, real-time decision making for patients and could potentially change how doctors manage prostate cancer on an individual basis.
“This marker is unique, as tumor growth rate obtained using it highly correlates with a patient’s overall survival – our ultimate goal of treatment,” says Dr. Leuva. “What I wish to do is be able to tell the patient that looking at your own data while you are on this medication, it is better to continue more or it is time to switch now.”
Dr. Leuva is tracking tumor growth rates of more than 20,000 Veterans who have received various prostate cancer therapies and studying what happens when a patient changes therapies. He is also trying to identify optimal sequencing of metastatic prostate cancer medications.
“We have observed that certain patients may benefit more by continuing the current treatment, despite slow rising PSA, as once they switch, their tumor growth rate accelerates. This phenomenon has not been described before, and we are looking to identify the patients who may benefit from continuing the medication,” said Dr. Leuva.
Dr. Leuva says the greatest need in research for Veterans is prospective / retrospective studies.
“It is very important, as the Veteran population is an older cohort of patients with higher comorbidities and lower performance status than what we see in usual patient populations of clinical trials. Veterans also have a higher African American population, which is underrepresented in many trials,” explained Dr. Leuva. “Thus, extrapolation of those trial results for Veterans may not yield similar results.”
To validate his model and guide care for all patients, Dr. Leuva hopes to follow similar groups of patients over time, and also plans to create a “virtual” comparator arm using the data from this Veterans study, which can be used as the control arm to test new therapies.
“This would mean trials will need less patients to answer various questions. This will make trials more cost- and time-efficient,” said Dr. Leuva, who also hopes to explore use of artificial intelligence to develop even more comprehensive prediction models and identify what biological cancer parameters can help identify effectiveness of one type of therapy versus another.
As Veterans continue in service through science, Conquer Cancer donors make it possible for researchers like Dr. Leuva to improve care for all patients.
"Cancer research requires time, patience, and persistence,” said Dr. Leuva. “Donors provide us protected time and the ability to focus on important research questions that lead to unbiased discovery and breakthroughs in our understanding and treatment of cancer.”