A Phase IB/II Study of Niraparib plus Immunotherapy to Treat Metastatic Castration-Resistant Prostate Cancer


Full Title

A Phase 1b-2 Study of Niraparib Combination Therapies for the Treatment of Metastatic Castration-Resistant Prostate Cancer


Prostate cancers initially need the male hormone testosterone for growth. Hormone therapies that lower the level of testosterone are among the most effective treatments for prostate cancers that have spread to other organs (metastasized). The benefits of hormone treatments do not last, however. Over time, many prostate cancers continue to grow despite hormonal therapies; these are called “castration-resistant prostate cancers” (CRPC).

In this study, researchers are assessing the safety and effectiveness of combining the drug niraparib with the investigational immunotherapy JNJ-63723283. Niraparib works by inhibiting PARP, a protein that helps cancer cells repair DNA that has been damaged by cancer treatments. When cancer cells repair damaged DNA, they can continue growing and multiplying, so depriving them of this power with a PARP inhibitor may be an effective approach to treatment.

JNJ-63723283 boosts the power of the immune system to find and kill cancer cells by blocking a protein called PD1. Researchers think that giving niraparib in combination with JNJ-63723283 will make prostate cancer cells a more obvious target for the immune system, and JNJ-63723283 will trigger the immune system to go after these cells and destroy them more effectively. Niraparib is taken orally (by mouth) while JNJ-63723283 is given intravenously (by vein).


To be eligible for this study, patients must meet several criteria, including but not limited to the following:

  • Patients must have CRPC that persists despite at least one, but no more than two regimens of androgen receptor (AR)-targeted therapy (such as abiraterone acetate with prednisone, enzalutamide, and apalutamide) for prostate cancer. Patients must have had at least 4 weeks of AR-targeted therapy.
  • Patients may not have previously received a PARP inhibitor.
  • At least 4 weeks must pass between the completion of previous treatment and entry into the study.
  • Patients must be physically well enough that they are fully ambulatory, capable of all self care, and are capable of all but physically strenuous activities. As an example, patients must be well enough that they would be able to carry out office work or light housework.
  • This study is for men age 18 and older.

For more information about this study and to inquire about eligibility, please contact Dr. Dana Rathkopf at 646-422-4379.





Disease Status

Relapsed or Refractory