ABSTRACT
PURPOSE: BRCA-associated cancers have increased sensitivity to poly(ADP-ribose) polymerase inhibitors (PARPis). This single arm, non-randomised, multicentre phase II trial evaluated the response rate of veliparib in patients with previously treated BRCA1/2- or PALB2-mutant pancreatic adenocarcinoma (PDAC). METHODS: Patients with stage III/IV PDAC and known germline BRCA1/2 or PALB2 mutation, 1-2 lines of treatment, Eastern Cooperative Oncology Group 0-2, were enrolled. Veliparib was dosed at a volume of 300 mg twice-daily (N = 3), then 400 mg twice-daily (N = 15) days 1-28. The primary end-point was to determine the response rate of veliparib; secondary end-points included progression-free survival (PFS), duration of response, overall survival (OS) and safety. RESULTS: Sixteen patients were enrolled; male N = 8 (50%). Median age was 52 years (range 43-77). Five (31%) had a BRCA1 and 11 (69%) had a BRCA2 mutation. Fourteen (88%) patients had received prior platinum-based therapy. No confirmed partial responses (PRs) were seen: one (6%) unconfirmed PR was observed at 4 months with disease progression (PD) at 6 months; four (25%) had stable disease (SD), whereas 11 (69%) had PD as best response including one with clinical PD. Median PFS was 1.7 months (95% confidence interval [CI] 1.57-1.83) and median OS was 3.1 months (95% CI 1.9-4.1). Six (38%) patients had grade III toxicity, including fatigue (N = 3), haematology (N = 2) and nausea (N = 1). CONCLUSIONS: Veliparib was well tolerated, but no confirmed response was observed although four (25%) patients remained on study with SD for ≥ 4 months. Additional strategies in this population are needed, and ongoing trials are evaluating PARPis combined with chemotherapy (NCT01585805) and as a maintenance strategy (NCT02184195).
Subject(s)
Adenocarcinoma/drug therapy , Benzimidazoles/therapeutic use , Carcinoma, Pancreatic Ductal/drug therapy , Genes, BRCA1 , Genes, BRCA2 , Mutation , Pancreatic Neoplasms/drug therapy , Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use , Adenocarcinoma/genetics , Adenocarcinoma/mortality , Adult , Aged , Benzimidazoles/adverse effects , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/mortality , Female , Humans , Male , Middle Aged , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/mortality , Prospective StudiesABSTRACT
PURPOSE: Granulocyte-colony stimulating factor (G-CSF) was used in CALGB 9741 to support dose-dense sequential chemotherapy with doxorubicin and cyclophosphamide (AC) followed by paclitaxel (P) (Citron et al. J Clin Oncol 21:1431-1439, 2003). However, myelosuppression is not known to be dose or schedule limiting for paclitaxel. We therefore conducted this trial to determine the need for routine G-CSF, using the pegylated product (pG-CSF), support during the paclitaxel component of dose-dense sequential chemotherapy in women with early stage breast carcinoma (BC). PATIENTS AND METHODS: Eligible patients received dose-dense chemotherapy consisting of four cycles of AC followed by four cycles of P at two week intervals. pG-CSF (Neulasta) was administered after each of four cycles of AC but was held after P. Planned enrollment was 59 pts. RESULTS: Of the first 15 patients, nine completed therapy without delays due to neutropenia but 6 (40%) did not, leading to implementation of the pre-specified early termination rule. Overall, 85% of P doses were successfully delivered on time. The mean treatment delay for the entire group due to neutropenia was 0.75 days. There was no significant correlation between neutropenia and prior WBC, ANC, or concurrent treatment with trastuzumab. Pts with neutropenia tended to be younger (Mean age 43.5) and have a lower BSA (1.65 m(2)). There were no febrile episodes due to omission of pG-CSF. CONCLUSION: When paclitaxel is administered in a dose-dense fashion without growth factor support brief treatment delays are common. Further study is needed to identify the minimal pG-CSF administration that will avoid treatment delays.
