A Phase 1 interventional study of Olaparib and Vorinostat in Breast Cancer Metastatic and Breast Cancer, sponsored by The Methodist Hospital Research Institute. Active, not recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-03-16.
Sponsored by The Methodist Hospital Research Institute · Phase 1, Interventional, and Treatment
The purpose of this study is to test the safety and preliminary efficacy of olaparib and vorinostat when used together in participants with relapsed/refractory and or metastatic breast cancer.
This is a Phase I/Ib study testing the safety and preliminary efficacy of olaparib and vorinostat when used together in participants with relapsed/refractory and or metastatic breast cancer. Cancer cells grow in an uncontrolled manner and this causes damage to their DNA (genetic makeup). Cancer cells that cannot repair this damage will not survive and die. Unfortunately, cancer cells contain certain proteins whose job is to repair DNA damage. Poly (adenosine 5' diphosphoribose) polymerase (PARP) and histone deacetylase (HDAC) are two such proteins. Olaparib stops PARP from working, and vorinostat stops histone deacetylase from working. The use of olaparib and vorinostat together may better block the ability of cancer cells to repair their DNA damage. This may lead to even better killing of cancer cells.
The study will be done in two parts. In part one of the study, different dose levels of olaparib and vorinostat will be tested in several study participants. This part of the study will allow us to see the doses of olaparib and vorinostat that can be used safely together in participants with relapsed/refractory and/or metastatic breast cancer. Up to 4 different dose levels will be studied. In part two of the study, the dose level of olaparib and vorinostat found to be the safest in the first part of the study will be tested. This part of the study will allow us to see how well relapsed/refractory and/or metastatic breast cancer responds to treatment with olaparib and vorinostat. Participants who received the dose level of olaparib and vorinostat found to be the safest in the first part of the study will also take part in part two of the study.
12,544 studies on the registry are indexed under Breast Neoplasms; 2,892 are open to participants now.
This study's planned enrollment of 28 is below the median of 72 across 9,303 interventional studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →The Methodist Hospital Research Institute is the lead sponsor of 157 studies on the registry; 60 are open to participants now.
Of its 25 completed or terminated interventional studies of FDA-regulated products, 15 (60%) have results posted.
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Exclusion Criteria:
Phase I: Olaparib and vorinostat will be orally administered for 4 28-day cycles. Dose levels (DLs) are as follows: DL -1, 100 mg twice daily (b.i.d.) olaparib and 300 mg for 5 consecutive days per week vorinostat; DL 0 (starting dose), 200 mg twice daily (b.i.d.) olaparib and 300 mg once daily (q.d.) vorinostat; DL 1, 300 mg b.i.d. olaparib and 300 mg q.d. vorinostat; and DL 2, 300 mg b.i.d. olaparib and 400 mg q.d. vorinostat. . Patients who derive clinical benefit (CR, PR, or SD) after 4 cycles of treatment can continue to receive the study treatment until they experience unacceptable AEs or disease progression. Phase Ib: Olaparib and vorinostat will be administered at the maximum tolerated dose (MTD) determined in the Phase I portion of the study for 4 28-day cycles. Participants who derive clinical benefit (complete response, partial response, or stable disease) after 4 cycles will continue to receive study treatment until unacceptable toxicity or disease progression.
Drug: Olaparib · Drug: Vorinostat
PARP inhibitor
Also known as: AZD2281, KU-0059436, Lynparza
HDAC inhibitor
Also known as: Suberanilohydroxamic acid, Zolinza
MTD
Determine the MTD of the olaparib and vorinostat combination
Time frame: 16 weeks
Dose-limiting toxicities (DLTs) and other adverse events
Determine the DLTs and other adverse events associated with the olaparib and vorinostat combination, as assessed by the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) v4.03
Time frame: 16 weeks
Recommended Phase 2 dose (RP2D)
Determine the RP2D of the olaparib and vorinostat combination
Time frame: 16 weeks
Antitumor activity
Assess the antitumor activity of the olaparib and vorinostat combination in an expansion cohort of patients with relapsed/refractory and/or metastatic breast cancer, as assessed by the Response Evaluation Criteria in Solid Tumors (RECIST) 1:1
Time frame: 16 weeks
This study is active, not recruiting, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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The Methodist Hospital Research Institute