A phase I trial of paclitaxel, cisplatin, and veliparib in the treatment of persistent or recurrent carcinoma of the cervix: an NRG Oncology Study (NCT#01281852)

Background

Preclinical studies demonstrate poly(ADP-ribose) polymerase (PARP) inhibition augments apoptotic response and sensitizes cervical cancer cells to the effects of cisplatin. Given the use of cisplatin and paclitaxel as first-line treatment for persistent or recurrent cervical cancer, we aimed to estimate the maximum tolerated dose (MTD) of the PARP inhibitor veliparib when added to chemotherapy.

Patients and methods

Women with persistent or recurrent cervical carcinoma not amenable to curative therapy were enrolled. Patients had to have received concurrent chemotherapy and radiation as well as possible consolidation chemotherapy; have adequate organ function. The trial utilized a standard 3 + 3 phase I dose escalation with patients receiving paclitaxel 175 mg/m2 on day 1, cisplatin 50 mg/m2 on day 2, and escalating doses of veliparib ranging from 50 to 400 mg orally two times daily on days 1-7. Cycles occurred every 21 days until progression. Dose-limiting toxicities (DLTs) were assessed at first cycle. Fanconi anemia complementation group D2 (FANCD2) foci was evaluated in tissue specimens as a biomarker of response.

Results

Thirty-four patients received treatment. DLTs (n = 1) were a grade 4 dyspnea, a grade 3 neutropenia lasting ≥3 weeks, and febrile neutropenia. At 400 mg dose level (DL), one of the six patients had a DLT, so the MTD was not reached. Across DLs, the objective response rate (RR) for 29 patients with measurable disease was 34% [95% confidence interval (CI), 20%-53%]; at 400 mg DL, the RR was 60% (n = 3/5; 95% CI, 23%-88%). Median progression-free survival was 6.2 months (95% CI, 2.9-10.1), and overall survival was 14.5 months (95% CI, 8.2-19.4). FANCD2 foci was negative or heterogeneous in 31% of patients and present in 69%. Objective RR were not associated with FANCD2 foci (P = 0.53).

Conclusions

Combining veliparib with paclitaxel and cisplatin as first-line treatment for persistent or recurrent cervical cancer patients is safe and feasible.

Clinical trial information

NCT01281852.

A phase 2, randomized, double-blind, placebo- controlled study of chemo-immunotherapy combination using motolimod with pegylated liposomal doxorubicin in recurrent or persistent ovarian cancer: a Gynecologic Oncology Group partners study

BACKGROUND

A phase 2, randomized, placebo-controlled trial was conducted in women with recurrent epithelial ovarian carcinoma to evaluate the efficacy and safety of motolimod-a Toll-like receptor 8 (TLR8) agonist that stimulates robust innate immune responses-combined with pegylated liposomal doxorubicin (PLD), a chemotherapeutic that induces immunogenic cell death.

PATIENTS AND METHODS

Women with ovarian, fallopian tube, or primary peritoneal carcinoma were randomized 1 : 1 to receive PLD in combination with blinded motolimod or placebo. Randomization was stratified by platinum-free interval (≤6 versus >6-12 months) and Gynecologic Oncology Group (GOG) performance status (0 versus 1). Treatment cycles were repeated every 28 days until disease progression.

RESULTS

The addition of motolimod to PLD did not significantly improve overall survival (OS; log rank one-sided P = 0.923, HR = 1.22) or progression-free survival (PFS; log rank one-sided P = 0.943, HR = 1.21). The combination was well tolerated, with no synergistic or unexpected serious toxicity. Most patients experienced adverse events of fatigue, anemia, nausea, decreased white blood cells, and constipation. In pre-specified subgroup analyses, motolimod-treated patients who experienced injection site reactions (ISR) had a lower risk of death compared with those who did not experience ISR. Additionally, pre-treatment in vitro responses of immune biomarkers to TLR8 stimulation predicted OS outcomes in patients receiving motolimod on study. Immune score (tumor infiltrating lymphocytes; TIL), TLR8 single-nucleotide polymorphisms, mutational status in BRCA and other DNA repair genes, and autoantibody biomarkers did not correlate with OS or PFS.

CONCLUSIONS

The addition of motolimod to PLD did not improve clinical outcomes compared with placebo. However, subset analyses identified statistically significant differences in the OS of motolimod-treated patients on the basis of ISR and in vitro immune responses. Collectively, these data may provide important clues for identifying patients for treatment with immunomodulatory agents in novel combinations and/or delivery approaches.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT 01666444.

A phase II evaluation of motesanib (AMG 706) in the treatment of persistent or recurrent ovarian, fallopian tube and primary peritoneal carcinomas: a Gynecologic Oncology Group study

OBJECTIVES

Vascular endothelial growth factors (VEGF) and their receptors have a critical role in stimulating the growth of ovarian cancer cells. Motesanib is a small molecule inhibitor of multiple receptor tyrosine kinases including VEGF receptors 1-3, as well as c-KIT and platelet-derived growth factor which are related to the VEGF family.

PATIENTS AND METHODS

Twenty-two eligible patients with recurrent ovarian, fallopian tube or primary peritoneal carcinoma were treated with an oral daily dose of 125 mg of motesanib. Peripheral blood was analyzed for circulating tumor cells (CTC) and circulating endothelial cells/circulating endothelial progenitors (CEC/CEP), VEGF levels and cell-free circulating DNA (cfDNA).

RESULTS

The study was abruptly halted after four patients developed posterior reversible encephalopathy syndrome. One patient had a partial response and seven patients had stable disease at the time they were removed from study treatment. Twelve of the 22 patients (50%) had indeterminate responses at trial closure. Early closure without clinical efficacy data precludes meaningful correlative studies.

CONCLUSIONS

The serious central nervous system toxicity observed in patients with recurrent ovarian cancer precluded full examination of this agent in this population. There were no clear cut explanations for the high incidence of this known class effect in the study population compared with patients with other cancers.

In vivo gene delivery and expression by bacteriophage lambda vectors

Aims

Bacteriophage vectors have potential as gene transfer and vaccine delivery vectors because of their low cost, safety and physical stability. However, little is known concerning phage-mediated gene transfer in mammalian hosts. We therefore performed experiments to examine phage-mediated gene transfer in vivo.

Methods and Results

Mice were inoculated with recombinant lambda phage containing a mammalian expression cassette encoding firefly luciferase (luc). Efficient, dose-dependent in vivo luc expression was detected, which peaked within 24 h of delivery and declined to undetectable levels within a week. Display of an integrin-binding peptide increased cellular internalization of phage in vitro and enhanced phage-mediated gene transfer in vivo. Finally, in vivo depletion of phagocytic cells using clodronate liposomes had only a minor effect on the efficiency of phage-mediated gene transfer.

Conclusions

Unmodified lambda phage particles are capable of transducing mammalian cells in vivo, and may be taken up – at least in part – by nonphagocytic mechanisms. Surface modifications that enhance phage uptake result in more efficient in vivo gene transfer.

Significance and Impact of the Study

These experiments shed light on the mechanisms involved in phage-mediated gene transfer in vivo, and suggest new approaches that may enhance the efficiency of this process.

Serial ductal lavage for biomarker assessment in a phase 2 prevention study with tamoxifen

1509

Background: Effective methods of epithelial sampling to measure breast-specific biomarkers will aid the rapid evaluation of new preventive interventions. We report a proof-of-principle Phase 2 study to assess the utility of ductal lavage (DL) to measure biomarkers using tamoxifen (TAM) as the gold standard prevention agent. Methods: We enrolled women with a 5-year Gail risk >1.6 or the unaffected breast of women with breast cancer =1 cm. After entry DL, participants chose TAM or observation (OBS), and underwent repeat DL 6 months later. Samples were processed for cytology and immunohistochemistry for ER and Ki-67 labeling indices (LIs). If =1 duct showed atypia, the sample was called atypical. LI data were analyzed by duct (comparing the same duct at 2 time points) and by woman (comparing the mean of all ducts at 2 time points). Results: Of 168 women recruited, 135 (80%) underwent entry and repeat DL; 82 (49%) had sufficient cells for analysis at both time points (mean age 50 years, mean Gail 3.0). 44 chose observation and 38 chose TAM. Cytologic findings, by woman and by duct, showed significantly greater net improvement (from atypical to benign) in the TAM than in the OBS group (see table ). The repeat ER and Ki-67 LIs showed a significant reduction from entry within the TAM group (p=0.01 and 0.0001, respectively), but not in the OBS group when analysed by duct. Similarly, in analyses by woman, the ER and Ki-67 LIs decreased from entry to repeat DL within the TAM group (p=0.046 and 0.004 respectively), with minimal changes in the observation group. Between-group data are shown in the table and are similar to the within- group differences. Conclusions: Using DL, we saw the expected changes in TAM-related biomarkers, with stronger reductions in duct-to- duct comparisons than when findings were averaged across ducts in individual women. However, the 51% attrition rate of subjects from recruitment to biomarker analyses, along with the expense of DL, raises questions regarding the efficiency of this procedure in biomarker assessment over time.

[Table: see text]

No significant financial relationships to disclose.