Prostate Cancer Drug Trial Failed to Improve Survival
A clinical study of berzosertib in patients with advanced prostate cancer showed no significant benefit.
Updated on Oct. 5, 2026 in Cancer
A clinical trial evaluating the drug berzosertib combined with carboplatin failed to improve outcomes for patients with pretreated metastatic castration-resistant prostate cancer (mCRPC). The study, which concluded in July 2020, found no evidence that the targeted therapy extended survival.
Why it matters
Researchers hoped that combining chemotherapy with ATR inhibition would improve treatment efficacy by forcing cancer cells to rely on specific stress-response pathways. This trial's negative result indicates that this strategy did not overcome resistance in heavily pretreated mCRPC patients.
In an open-label trial of 73 patients with mCRPC, the combination of berzosertib and carboplatin did not meaningfully improve survival compared to docetaxel and carboplatin. Every treated patient experienced at least one adverse event, including significant rates of thrombocytopenia.
The details
The treatment regimen aimed to exploit replication stress in cancer cells, hypothesizing that blocking the ATR kinase protein would make cells hypersensitive to DNA damage caused by carboplatin. Patients were randomly assigned to receive either the experimental ATR inhibitor or docetaxel alongside the chemotherapy agent every 21 days. The approach proved ineffective in these patients, and none of those who crossed over to the experimental regimen showed a clinical response.
Timeline
June 2019: Trial enrollment began.
July 2020: Trial enrollment ended.
Health Landscape
The development of ATR kinase inhibitors for solid tumors continues to be a major area of investigation for targeting DNA damage response pathways in oncology. This trial provides a critical data point on the limitations of this approach in the context of metastatic castration-resistant prostate cancer.
Patients with advanced prostate cancer should discuss all available standard-of-care options and clinical trial opportunities with their oncology team. It is essential to consult a physician to understand how specific genetic profiles or biomarkers might influence the efficacy of various treatment protocols.
The takeaway
This trial highlights the difficulty of addressing treatment resistance in metastatic prostate cancer through current ATR-targeted strategies. Patients and caregivers should prioritize discussions with their specialists regarding the most effective, evidence-backed therapies currently available for their specific disease stage.
Further reading
For broader information on current research and treatment updates, explore our Cancer section.
Source note: This article includes information reported by OncLive.
