A phase I study of veliparib in combination with metronomic cyclophosphamide in adults with refractory solid tumors and lymphomas

Shivaani Kummar, Jiuping Ji, Robert Morgan, Heinz Josef Lenz, Shannon L. Puhalla, Chandra P. Belani, David R. Gandara, Deborah Allen, Brian Kiesel, Jan H. Beumer, Edward M. Newman, Larry Rubinstein, Alice Chen, Yiping Zhang, Lihua Wang, Robert J. Kinders, Ralph E. Parchment, Joseph E. Tomaszewski, James H. Doroshow

Research output: Contribution to journalArticlepeer-review

173 Scopus citations


Purpose: Oral administration of the alkylating agent cyclophosphamide at low doses, metronomic dosing, is well tolerated, with efficacy in multiple tumor types. PARP inhibition potentiates effects of cyclophosphamide in preclinical models. We conducted a phase I trial of the PARP inhibitor veliparib and metronomic cyclophosphamide in patients with refractory solid tumors and lymphoid malignancies. Experimental Design: Objectives were to establish the safety and maximum tolerated dose (MTD) of the combination; characterize veliparib pharmacokinetics (PK); measure poly(ADP-ribose) (PAR), a product of PARP, in tumor biopsies and peripheral blood mononuclear cells (PBMC); and measure the DNA-damage marker γH2AX in PBMCs and circulating tumor cells (CTC). Cyclophosphamide was administered once daily in 21-day cycles in combination with veliparib administered once daily for 7, 14, or 21 days. Results: Thirty-five patients were enrolled. The study treatment was well tolerated, and the MTD was established as veliparib 60 mg with cyclophosphamide 50 mg given once daily. Seven patients had partial responses; an additional six patients had disease stabilization for at least six cycles. PAR was significantly decreased in PBMCs (by at least 50%) and tumor biopsies (by at least 80%) across dose levels (DL); γH2AX levels were increased in CTCs from seven of nine patients evaluated after drug administration. Conclusions: The combination of veliparib with metronomic cyclophosphamide is well tolerated and shows promising activity in a subset of patients with BRCA mutations. A phase II trial of the combination compared with single-agent cyclophosphamide is ongoing in BRCA-positive ovarian cancer, triple-negative breast cancer, and low-grade lymphoma.

Original languageEnglish (US)
Pages (from-to)1726-1734
Number of pages9
JournalClinical Cancer Research
Issue number6
StatePublished - Mar 15 2012
Externally publishedYes

ASJC Scopus subject areas

  • Oncology
  • Cancer Research


Dive into the research topics of 'A phase I study of veliparib in combination with metronomic cyclophosphamide in adults with refractory solid tumors and lymphomas'. Together they form a unique fingerprint.

Cite this