A phase I study of intravenous and oral rucaparib in combination with chemotherapy in patients with advanced solid tumours

BACKGROUND

This study evaluated safety, pharmacokinetics, and clinical activity of intravenous and oral rucaparib, a poly(ADP-ribose) polymerase inhibitor, combined with chemotherapy in patients with advanced solid tumours.

METHODS

Initially, patients received escalating doses of intravenous rucaparib combined with carboplatin, carboplatin/paclitaxel, cisplatin/pemetrexed, or epirubicin/cyclophosphamide. Subsequently, the study was amended to focus on oral rucaparib (once daily, days 1-14) combined with carboplatin (day 1) in 21-day cycles. Dose-limiting toxicities (DLTs) were assessed in cycle 1 and safety in all cycles.

RESULTS

Eighty-five patients were enrolled (22 breast, 15 ovarian/peritoneal, and 48 other primary cancers), with a median of three prior therapies (range, 1-7). Neutropenia (27.1%) and thrombocytopenia (18.8%) were the most common grade ⩾3 toxicities across combinations and were DLTs with the oral rucaparib/carboplatin combination. Maximum tolerated dose for the combination was 240 mg per day oral rucaparib and carboplatin area under the curve 5 mg ml-1 min-1. Oral rucaparib demonstrated dose-proportional kinetics, a long half-life (≈17 h), and good bioavailability (36%). Pharmacokinetics were unchanged by carboplatin coadministration. The rucaparib/carboplatin combination had radiologic antitumour activity, primarily in BRCA1- or BRCA2-mutated breast and ovarian/peritoneal cancers.

CONCLUSIONS

Oral rucaparib can be safely combined with a clinically relevant dose of carboplatin in patients with advanced solid tumours (Trial registration ID: NCT01009190).

Abstract P6-11-13: Phase Ib study evaluating the safety and clinical activity of lumretuzumab combined with pertuzumab and paclitaxel in HER2-low metastatic breast cancer

Background: Inhibition of HER2 and HER3 heterodimerisation is a novel treatment concept in HER2-”low” expressing breast cancer (BC). Lumretuzumab, a glycoengineered monoclonal anti-HER3 antibody, in combination with pertuzumab has demonstrated synergistic anti-tumor activity in preclinical HER2–low expressing preclinical BC models.

Methods: This open-label, multicenter phase I study selectively enrolled metastatic BC patients (pts) expressing HER3 protein and low levels of HER2 (defined as IHC 1+ and 2+ and ISH-negative) in a formalin-fixed paraffin-embedded pretreatment tumor biopsy sample. Eligible pts were treated with a combination of paclitaxel (PA) qw plus lumretuzumab (L) and pertuzumab (P) q3w in three dose cohorts. The safety, antitumor activity and tumor biomarkers including protein expression (IHC, MS) and mutational data (NGS) in association with clinical activity were evaluated.

Results: Overall, 35 pts were included in this study. The median age was 60 (range: 33 to 77) years. The median number of prior treatments for metastatic disease ranged from 0 to 5 with 23 pts (65.7%) without prior chemotherapy for metastatic disease. Cohort 1 was treated with PA at 80 mg/m2, L at 1000 mg and P at 840 mg for Cycle 1 followed by 420 mg for the following cycles. This cohort was stopped after two pts both experienced grade 3 diarrhea within the first treatment cycle which was considered a dose-limiting toxicity (DLT). For Cohort 2 the dose of L was reduced to 500 mg based on PK modelling and simulation data. No DLTs were seen for the first 6 pts. A total of 20 pts were recruited with an objective response rate (ORR) and disease control rate (DCR) of 30% and 75%, respectively, and 56% and 78%, respectively, for 1st-line pts (n=9) in this cohort. Diarrhea (≥G3) and hypokalemia (≥G3) occurred in 50% and 55% of pts, respectively, and all pts experienced chronic diarrhea throughout the course of treatment. For Cohort 3 the dose of L was maintained at 500 mg, PA at 80 mg/m2, and P was administered at 420 mg at all cycles. In addition, a prophylactic loperamide regimen was introduced. Altogether, 13 pts - all 1st-line for metastatic disease - were treated. No DLTs were seen for the first 6 pts. Diarrhea (≥G3) and hypokalemia (≥G3) were reduced to 31% and 15%, respectively, but chronic diarrhea was still observed throughout the treatment in all pts. The ORR and DCR were 31% and 77%, respectively. Preliminary mechanistic safety experiments revealed HER2/HER3-dependent chloride channels in the intestine as likely cause of diarrhea. Biomarker data will be presented along with updated clinical and safety data.

Conclusions: The combination of L, P and PA was associated with high rates of persistent diarrhea. Dose modifications and prophylactic anti-diarrheal medication led to significantly reduced diarrhea intensity but did not change the incidence and persistence of diarrhea overall. Despite encouraging clinical activity especially in 1st line pts, the therapeutic window of this combination is too low to warrant further clinical development.

Citation Format: Schneeweiss A, Park-Simon T-W, Albanell J, Lassen U, Cortes J, Dieras V, May M, Schindler C, Marmé F, Cejalvo JM, Martinez-Garcia M, Gonzalez I, Lopez-Martin J, Welt A, Joly F, Michielin F, Jacob W, Adessi C, Moisan A, Meneses-Lorente G, James I, Ceppi M, Hasmann M, Weisser M, Cervantes A. Phase Ib study evaluating the safety and clinical activity of lumretuzumab combined with pertuzumab and paclitaxel in HER2-low metastatic breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-11-13.

Abstract OT1-02-03: Phase I multicenter clinical trial evaluating the combination of trastuzumab emtansine (T-DM1) and non-pegylated liposomal doxorubicin (NPLD) in HER2-positive metastatic breast cancer (MBC) (MEDOPP038 study)

BACKGROUND:

Clinical efficacy and safety of T-DM1 for the treatment of HER2-positive MBC has been assessed in several phase II and III trials and is now considered the standard of care in taxane-and trastuzumab-progressing patients. However, although T-DM1 has shown encouraging antitumor activity in the advanced setting, several strategies to improve T-DM1 efficacy are currently evaluated, including the combination with non-pegylated liposomal doxorubicin (NPLD), considering that: i) doxorubicin is one of the most active chemotherapeutic agents against HER2-positive breast cancer; ii) the combination of doxorubicin and trastuzumab induces synergistic antitumor activity in HER2-overexpressing preclinical models; and iii) liposomal formulations of doxorubicin have a reduced risk of developing cardiac toxicity.

OBJECTIVES:

The primary objective of this trial is to determine the maximum tolerated dose (MTD) of the combination of T-DM1 and NPLD in patients with HER2-positive MBC naïve of anthracyclines and previously treated with trastuzumab and a taxane. The secondary objectives include 1) safety, with special emphasis on cardiac safety evaluated by left ventricular ejection fraction, high-sensitivity troponin I and B-type natriuretic peptide (BNP) levels, 2) pharmacokinetics, 3) antitumor activity, and the 4) role of single nucleotide polymorphisms of HER2 gene for developing cardiotoxicity.

TRIAL DESIGN:

This is a dose-finding, open-label, non-randomized and multicenter phase I clinical trial of T-DM1 at a fixed dose of 3.6 mg/kg IV in combination with three different dose levels (DL) of NPLD (45, 50, and 60 mg/m2) IV administered on Day 1 every three weeks. The trial follows a modified dose escalation scheme with a 3+3 design.A total of three patients will be included in the first cohort and observed for dose-limiting toxicities (DLTs) during the first two cycles of treatment. If none of these patients experiences a DLT, three other patients will be treated at the next DL. However, in case of at least one patient experiences a DLT, three more patients will be treated at the same DL. The MTD will be defined as the highest DL at which ≤1 of six patients experiences a DLT during the first two cycles of treatment. An expansion cohort of six additional patients at the MTD will be included.

ELIGIBILITY:

Anthracycline-naïve patients with HER2-positive MBC and up to two prior chemotherapy regimens in the advanced setting who previously were treated with trastuzumab and a taxane. ECOG performance status of 0-1. Adequate organ and cardiovascular function with LVEF ≥ 55%. RECIST v1.1 evaluable disease.

ACCRUAL:

A total of 12-24 patients will be enrolled at four sites in Spain and France. Recruitment was opened on September 2015. To date, four patients (three at DL1 and one at DL2) have been recruited.

Citation Format: López-Miranda E, Brain E, Saura C, Gligorov J, Dubot C, Dieras V, Suter TM, Aguirre E, Perez-García JM, Llombart A, Cortés J. Phase I multicenter clinical trial evaluating the combination of trastuzumab emtansine (T-DM1) and non-pegylated liposomal doxorubicin (NPLD) in HER2-positive metastatic breast cancer (MBC) (MEDOPP038 study) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT1-02-03.

Paclitaxel plus bevacizumab or paclitaxel as first-line treatment for HER2-negative metastatic breast cancer in a multicenter national observational study

BACKGROUND

Bevacizumab combined with paclitaxel as first-line chemotherapy for patients with HER2-negative metastatic breast cancer (MBC) has led to mixed results in randomized trials, with an improvement in progression-free survival (PFS) but no statistically significant overall survival (OS) benefit. Real-life data could help in assessing the value of this combination.

PATIENTS AND METHODS

This study aimed to describe the outcome following first-line paclitaxel with or without bevacizumab in the French Epidemiological Strategy and Medical Economics (ESME) database of MBC patients, established in 2014 by Unicancer. The primary and secondary end points were OS and PFS, respectively.

RESULTS

From 2008 to 2013, 14 014 MBC patient files were identified, including 10 605 patients with a HER2-negative status. Of these, 3426 received paclitaxel and bevacizumab (2127) or paclitaxel (1299) as first-line chemotherapy. OS adjusted for major prognostic factors was significantly longer in the paclitaxel and bevacizumab group compared with paclitaxel [hazard ratio (HR) 0.672, 95% confidence interval (CI) 0.601-0.752; median survival time 27.7 versus 19.8 months]. Results were consistent in all supportive analyses (using a propensity score for adjustment and as a matching factor for nested case-control analyses) and sensitivity analyses. Similar results were observed for the adjusted PFS, favoring the combination (HR 0.739, 95% CI 0.672-0.813; 8.1 versus 6.4 months).

CONCLUSIONS

In this large-scale, real-life setting, patients with HER2-negative MBC who received paclitaxel plus bevacizumab as first-line chemotherapy had a significantly better OS and PFS than those receiving paclitaxel. Despite robust methodology, real-life data are exposed to important potential biases, and therefore, results need to be treated with caution. Our data cannot therefore support extension of current use of bevacizumab in MBC.

Abstract LB-353: Mutational profile of metastatic breast cancers using whole-exome sequencing: a retrospective analysis of 216 samples from SAFIR01 / 02 / SHIVA / MOSCATO trials

Background: Major advances have been achieved in the understanding of breast cancer biology using high throughput technologies at the DNA and RNA levels. Most of these advances were made in early breast cancers (eBC) which are cured in about 80% of the cases. Nevertheless, little is known about metastatic breast cancers (mBC) which remain lethal in most of the cases.

Methods: Whole-exome sequencing was performed on 216 tumour-normal pairs from mBC patients who underwent a biopsy in the context of the SAFIR01/SAFIR02/SHIVA or MOSCATO prospective trials. TCGA dataset (n = 772) was used to assess frequency of mutations in eBC.

Findings: Twelve genes (TP53, PIK3CA, GATA3, ESR1, MAP3K1, CDH1, AKT1, MAP2K4, RB1, PTEN, CBFB, CDKN2A) were identified as drivers using MutSig algorithm (FDR<0.1). Eight genes (ESR1, FSIP2, FRAS1, OSBPL3, EDC4, PALB2, IGFN1, AGRN) were more frequently mutated in mBC as compared to eBC (TCGA, FDR<0.01). HR+/Her2- mBC presented a high prevalence (6.3%) of mutations on genes located on mTOR pathway (TSC1, TSC2) as compared to HR+/Her2- eBC (0.7%, p = 0.0004). A subset of HR+/Her2- mBC (n = 17, 12%) presented a high mutational load (>150 non-synonymous mutations). This subset was observed in 2% of early breast cancers (TCGA, p = 7.1e?06). The prevalence of this subset increased with the time from diagnosis of metastasis to biopsy. Highly mutated HR+/Her2- mBC (n = 17) presented higher rate of PIK3CA mutations (n = 12, 70%), high number of neoantigens, an APOBEC mutational signature and a poor outcome (multivariate analysis, HR = 4.68, 95%CI: 1.8-12.1, p = 0.001).

Interpretation: Whole exome sequencing of metastatic breast cancers identifies a subset of HR+/Her2- mBC who present a high mutational load. RB1, PALB2 and TSC1/2 mutations were found enriched in either mBC or HR+ mBC.

Fundings: Breast Cancer Research Foundation, Fondation ARC, Fondation Lombard-Odier “Philanthropia”, Odyssea, Operation Parrains Chercheurs, Dassault Foundation, French NCI: INCa-DGOS-INSERM 6043

Citation Format: Maud Kamal, Celine Lefebvre, Thomas Bachelot, Thomas Filleron, Marion Pedrero, Mario Campone, Jean-Charles Soria, Christophe Massard, Christelle Levy, Monica Arnedos, Julie Garrabey, Yannick Boursin, Marc Deloger, Yu Fu, Frederic Commo, Veronique Scott, Ludovic Lacroix, Emmanuel Martin, Veronique Dieras, Anthony Goncalves, Jean-Marc Ferrero, Gilles Romieu, Laurence Vanlemmens, Marie-Ange Mouret-Reynier, Jean-christophe Thery, Pierre Kerbrat, Severine Guiu, Florence Dalenc, Gilles Clapisson, Hervé Bonnefoi, Martha Jimenez, Christophe Le Tourneau, Fabrice Andre. Mutational profile of metastatic breast cancers using whole-exome sequencing: a retrospective analysis of 216 samples from SAFIR01 / 02 / SHIVA / MOSCATO trials. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-353.

Abstract P2-02-17: T-DM1 in HER2-negative metastatic breast cancer patients with HER2-amplified circulating tumor cells: Current status of the CirCe T-DM1 phase II trial

Background: Liquid biopsy can reassess key therapeutic targets in metastatic breast cancer. Several studies showed that a low albeit significant rate of metastatic breast cancer initially considered as HER2-negative can be reclassified as HER2-positive by systematic biopsy procedures. We report here the current status of the CirCe T-DM1 trial [NCT01975142] which aims to demonstrate the clinical utility of HER2 status reassessment on circulating tumor cells (CTCs).

Methods: The first step of the trial consists in CTC count and HER2/CEP17 FISH on detected CTCs (CellSearch, Janssen Diagnostics) in patients (pts) with measurable disease progressing after the second line of chemotherapy. Pts with amplified CTCs (HER2/CEP17 ratio equal or higher than 2.2) are eligible to the treatment step of the study in two distinct cohorts: low CTC count (1 or 2 HER2-amplified CTCs) and high CTC count (3 and more HER2-amplified CTCs). In the treatment step has a Simon's two stage design, the anti-HER2 antibody-drug conjugate T-DM1 being administered until tumor progression. The primary objective of the trial is the confirmed response rate (RECIST). This trial is supported by Roche.

Results: CirCe T-DM1 has been initiated in 10 centers in France. As of June 2015, 105 metastatic breast cancers pts considered as HER2-negative were screened. 29 pts (27%) had no CTC detected, 68 pts (65%) had at least 1 CTC detected with no HER2 amplification, and 8 pts (8%) exhibited HER2-amplified CTCs. Among the 8 pts, 1 pt had 5 HER2-amplified CTC, 2 pts had 2 HER2-amplified CTC and 5 pts had 1 HER2-amplified CTC. HER2/CEP17 ratios among HER2-amplified CTCs ranged from 2.5 to 7. Five of the 8 pts were treated by T-DM1. One objective confirmed partial tumor response has been observed (20%).

Conclusion: The accrual is ongoing; the first efficacy assessment will occur after having treated 14 pts. This innovative trial highlights the promise and the complexity of liquid biopsy-based programs in the era of precision medicine: scarcity of the target, reliability and reproducibility of the target assessment, major efficacy when the target is matched to the appropriate drug.

Citation Format: Bidard F-C, Romieu G, Jacot W, Cottu P, Dieras V, Lerebours F, Servent V, Luporsi E, Lortholary A, Tubiana-Mathieu N, Espie M, Bollet M, Bourgeois H, Renaud N, Pelissier S, Armanet S, Baeten K, Pierga J-Y. T-DM1 in HER2-negative metastatic breast cancer patients with HER2-amplified circulating tumor cells: Current status of the CirCe T-DM1 phase II trial. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-02-17.

Abstract CT322: Efficacy of first-line capecitabine (CAP) ± bevacizumab (BEV) according to risk factors in the RIBBON-1 randomized phase III trial in locally recurrent/metastatic breast cancer (LR/mBC)

BACKGROUND: Analysis of data from 2203 patients (pts) with HER2-negative LR/mBC treated in the single-arm ATHENA study suggested that overall survival (OS) expectancy of a well-defined subset of pts with hormone receptor-positive LR/mBC was similar to that of pts with triple-negative breast cancer (TNBC). We used prognostic factors from ATHENA to analyze efficacy in the CAP cohort of the RIBBON-1 trial.

PATIENTS AND METHODS: In the CAP cohort of RIBBON-1, pts with LR/mBC were randomized 2:1 to receive CAP with either BEV 15 mg/kg q3w (N=409) or placebo (PLA; N=206). The primary endpoint was investigator-assessed progression-free survival (PFS). Objective response rate (ORR) and 1-year OS rate were secondary endpoints. Exploratory efficacy analyses were done in three subgroups: TNBC; high-risk hormone receptor positive (>2 risk factors); and low-risk hormone receptor positive (≤2 risk factors) using the remaining risk factors identified in ATHENA (liver metastases/≥3 involved organs; disease-free interval [DFI] ≤24 months; prior anthracycline/taxane). The data cut-off was July 31, 2008.

RESULTS: In all three subgroups, PFS and ORR numerically favored BEV-CAP, consistent with the significant PFS and ORR benefit in the intent-to-treat population. Median PFS, median OS, and 1-year OS rate with PLA-CAP suggested a similarly poor prognosis in pts with TNBC and pts with high-risk hormone receptor-positive LR/mBC.

CONCLUSIONS: In these exploratory analyses, median OS in pts with high-risk hormone receptor-positive LR/mBC was short and similar to that in pts with TNBC, as seen in the ATHENA exploratory analysis.

OutcomePLA-CAPBEV-CAPTNBCN=50N=87PFS events, n (%)42 (84)74 (85)PFS unstratified HR (95% CI)0.72 (0.49-1.06)Median PFS, months (95% CI)4.2 (3.5-5.9)6.1 (4.3-8.2)ORR, % (95% CI)10.6 (3.5-23.1)30.3 (20.2-41.9)1-year OS rate, % (95% CI)71 (55-81)70 (59-79)Deaths, n (%)26 (52)47 (54)Median OS, months (95% CI)20.5 (15.8-NR)19.7 (14.6-23.2)Hormone receptor-positive disease with additional risk factors*N=56N=92PFS events, n (%)42 (75)72 (78)PFS unstratified HR (95% CI)0.80 (0.54-1.17)Median PFS, months (95% CI)4.4 (3.1-6.2)7.1 (4.3-8.6)ORR, % (95% CI)22.4 (11.8-36.6)27.7 (18.4-38.6)1-year OS rate, % (95% CI)66 (52-77)80 (70-87)Deaths, n (%)32 (57)52 (57)Median OS, months (95% CI)19.6 (12.9-23.4)20.8 (17.5-25.7)Hormone receptor-positive disease with limited additional risk factors**N=90N=220PFS events, n (%)68 (76)139 (63)PFS unstratified HR (95% CI)0.67 (0.50-0.89)Median PFS, months (95% CI)7.7 (6.0-8.4)10.6 (9.1-12.0)ORR, % (95% CI)36.8 (24.4-50.7)41.5 (33.8-49.6)1-year OS rate, %86 (77-92)85 (80-89)Deaths, n (%)34 (38)83 (38)Median OS, months (95% CI)28.4 (23.4-NR)29.0 (25.8-NR)*ER and/or PgR positive with >2 risk factors (liver metastases/≥3 involved organs; DFI ≤24 months; prior anthracycline/taxane); **ER and/or PgR positive with ≤2 risk factors.

Citation Format: Nicholas J. Robert, Veronique Dieras, Christian Jackisch, Stefanie Srock, Ulrich Freudensprung, Leonardo Faoro, Joyce O’Shaughnessy. Efficacy of first-line capecitabine (CAP) ± bevacizumab (BEV) according to risk factors in the RIBBON-1 randomized phase III trial in locally recurrent/metastatic breast cancer (LR/mBC). [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr CT322. doi:10.1158/1538-7445.AM2014-CT322

REBECA: a phase I study of bevacizumab and whole-brain radiation therapy for the treatment of brain metastasis from solid tumours

BACKGROUND

Brain metastases (BMs) are associated with a poor prognosis. Standard treatment comprises whole-brain radiation therapy (WBRT). As neo-angiogenesis is crucial in BM growth, combining angiogenesis inhibitors such as bevacizumab with radiotherapy is of interest. We aimed to identify the optimal regimen of bevacizumab combined with WBRT for BM for phase II evaluation and provide preliminary efficacy data.

PATIENTS AND METHODS

In this multicentre single-arm phase I study with a 3 + 3 dose-escalation design, patients with unresectable BM from solid tumours received three cycles of bevacizumab at escalating doses [5, 10 and 15 mg/kg every 2 weeks at dose levels (DL) 0, 1 and 2, respectively] and WBRT (30 Gy/15 fractions/3 weeks) administered from day 15. DL3 consisted of bevacizumab 15 mg/kg with WBRT from day 15 in 30 Gy/10 fractions/2 weeks. Safety was evaluated using NCI-CTCAE version 3. BM response (RECIST 1.1) was assessed by magnetic resonance imaging at 6 weeks and 3 months after WBRT.

RESULTS

Nineteen patients were treated, of whom 13 had breast cancer. There were no DLTs. Grade 1-2 in-field and out-field toxicities occurred for five and nine patients across all DLs, respectively, including three and six patients (including one patient with both, so eight patients overall) of nine patients in DL3. One patient experienced BM progression during treatment (DL0). At the 3-month post-treatment assessment, 10 patients showed a BM response: one of three treated at DL0, one of three at DL1, two of three at DL2 and six of seven at DL3, including one complete response. BM progression occurred in five patients, resulting in two deaths. The remaining patient died from extracranial disease progression.

CONCLUSION

Bevacizumab combined with WBRT appears to be a tolerable treatment of BM. DL3 warrants further efficacy evaluation based on the favourable safety/efficacy balance. ClinicalTrials.gov Identifier: NCT01332929.

Phase I expansion and pharmacodynamic study of the oral MEK inhibitor RO4987655 (CH4987655) in selected patients with advanced cancer with RAS-RAF mutations

PURPOSE

This phase I expansion study assessed safety, pharmacodynamic effects, and antitumor activity of RO4987655, a pure MEK inhibitor, in selected patients with advanced solid tumor.

EXPERIMENTAL DESIGN

We undertook a multicenter phase I two-part study (dose escalation and cohort expansion). Here, we present the part 2 expansion that included melanoma, non-small cell lung cancer (NSCLC), and colorectal cancer with oral RO4987655 administered continuously at recommended doses of 8.5 mg twice daily until progressive disease (PD). Sequential tumor sampling investigated multiple markers of pathway activation/tumor effects, including ERK phosphorylation and Ki-67 expression. BRAF and KRAS testing were implemented as selection criteria and broader tumor mutational analysis added.

RESULTS

Ninety-five patients received RO4987655, including 18 BRAF-mutant melanoma, 23 BRAF wild-type melanoma, 24 KRAS-mutant NSCLC, and 30 KRAS-mutant colorectal cancer. Most frequent adverse events were rash, acneiform dermatitis, and gastrointestinal disorders, mostly grade 1/2. Four (24%) of 17 BRAF-mutated melanoma had partial response as did four (20%) of 20 BRAF wild-type melanoma and two (11%) of 18 KRAS-mutant NSCLC. All KRAS-mutant colorectal cancer developed PD. Paired tumor biopsies demonstrated reduced ERK phosphorylation among all cohorts but significant differences among cohorts in Ki-67 modulation. Sixty-nine percent showed a decrease in fluorodeoxyglucose uptake between baseline and day 15. Detailed mutational profiling confirmed RAS/RAF screening and identified additional aberrations (NRAS/non-BRAF melanomas; PIK3CA/KRAS colorectal cancer) without therapeutic implications.

CONCLUSIONS

Safety profile of RO4987655 was comparable with other MEK inhibitors. Single-agent activity was observed in all entities except colorectal cancer. Evidence of target modulation and early biologic activity was shown among all indications independent of mutational status. Clin Cancer Res; 20(16); 4251-61. ©2014 AACR.

A phase I pharmacokinetic study of the vascular disrupting agent ombrabulin (AVE8062) and docetaxel in advanced solid tumours

BACKGROUND

The vascular disrupting agent ombrabulin shows synergy with docetaxel in vivo. Recommended phase II doses were determined in a dose escalation study in advanced solid tumours.

METHODS

Ombrabulin (30-min infusion, day 1) followed by docetaxel (1-h infusion, day 2) every 3 weeks was explored. Ombrabulin was escalated from 11.5 to 42 mg m(-2) with 75 mg m(-2) docetaxel, then from 30 to 35 mg m(-2) with 100 mg m(-2) docetaxel. Recommended phase II dose cohorts were expanded.

RESULTS

Fifty-eight patients were treated. Recommended phase II doses were 35 mg m(-2) ombrabulin with 75 mg m(-2) docetaxel (35/75 mg m(-2); 13 patients) and 30 mg m(-2) ombrabulin with 100 mg m(-2) docetaxel (30/100 mg m(-2); 16 patients). Dose-limiting toxicities were grade 3 fatigue (two patients; 42/75, 35/100), grade 3 neutropaenic infection (25/75), grade 3 headache (42/75), grade 4 febrile neutropaenia (30/100), and grade 3 thrombosis (35/100). Toxicities were consistent with each agent; mild nausea/vomiting, asthaenia/fatigue, alopecia, and anaemia were common, as were neutropaenia and leukopaenia. Diarrhoea, nail disorders and neurological symptoms were frequent at 100 mg m(-2) docetaxel. Pharmacokinetic analyses did not show any relevant drug interactions. Ten patients had partial responses (seven at 30 mg m(-2) ombrabulin), eight lasting >3 months.

CONCLUSIONS

Sequential administration of ombrabulin with 75 or 100 mg m(-2) docetaxel every 3 weeks is feasible.

Abstract P3-15-04: A French prospective pilot study to identify dihydropyrimidine dehydrogenase (DPD) deficiency in breast cancer patients receiving capecitabine

Background: Health Authorities point out that DPD deficiency confers a significant risk of major toxicity for patients receiving capecitabine. Identification of at-risk patients is thus of major concern. This multicentric prospective study of the French GPCO group (Groupe de Pharmacologie Clinique Oncologique, Unicancer) evaluated the sensitivity, specificity and predictive values of DPD phenotyping and genotyping to predict severe cap-related toxixity in metastatic breast cancer patients.

Methods: 303 patients were included between February 2009 and February 2011 (15 institutions). Eighty-eight% received capecitabine as monotherapy, 28% were treated as first line (mean dose at 1st cycle 1957 mg/m2/d). Pre-treatment uracil (U, physiological DPD substrate) plasma concentration was measured in 286 patients (HPLC assay). DPD genotyping (IVS14+1G>A, 2846A>T, 1679T>G, 464T>A) was performed on 281 patients. Severe toxicity (G3-4 CTCAE v3 criteria) was measured over cycles 1-2.

Results: Grade 3-4 toxicity (diarrhea, vomiting, hematoxicity, hand-foot syndrome) has been observed in 19.6% of patients (one toxic death). A marked trend for higher U concentrations has been noted in patients developing severe toxicity vs those who didn't (median 12.7 ng/ml (Q1-Q3 9-17) vs median 10.2 ng/ml (range 8-13), respectively, p = 0.014). However, ROC curve has showed that this difference was too small for use as a reliable toxicity predictor. The patient with toxic death had an elevated U concentration at 17 ng/ml. Among the 7 patients with a DPD mutation (3 pts IVS14+1, 3 pts 2846A>T, one 1679T>G, all heterozygous), 5 developed severe toxicity (including the toxic death, 2846A>T), one did not, and the last one was not documented. Relative risk for developing severe toxicity was 4.60 in mutated patients vs wild-type patients (95%CI 2.95-7.16, p = 0.001); positive and negative predictive values were 83.3% and 81.9%, respectively; specificity was 99.5% and sensitivity was 9.8%.

Conclusions: Breast cancer patients harbouring a DPD variant allele are at risk to develop severe, up to lethal, capecitabine-related toxicity. Pre-treatment U measurement remains to be more firmly established as a reliable predictor of capecitabine toxicity. These observations are of major interest for breast cancer patients candidate for capecitabine therapy.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-15-04.

Abstract OT1-1-10: CirCe T-DM1 phase II trial: Assessing the relevance of HER2-amplified circulating tumor cells as a tool to select HER2-negative metastatic breast cancer for treatment with T-DM1

Background: T-DM1 has demonstrated its efficacy in the second line of HER2-positive metastatic breast cancer patients. Several studies reported that some breast cancers considered as HER2-negative do have HER2-positive circulating tumor cells (CTC). Our previous report (Lightart & Bidard, Ann Oncol 2013) showed that the reliability of such discrepancy between primary tumor and CTC is directly related to the number of CTC analyzed. This study aims at studying the efficacy of T-DM1 in this setting.

Trial design: CirCe T-DM1 is a single arm two-step phase II multicenter study with adaptive design. Patients with HER2-negative measurable metastatic breast cancer will be screened by the FDA-approved CellSearch system, before the start of a second line treatment. HER2/CEP17 ratio will be quantified by FISH on CTC (Veridex). Patients with non HER2-amplified CTC or no CTC will be excluded from the study. Patients with HER2-amplified CTC will be treated by T-DM1 (Roche) single agent q3w, in either cohort “L” (low count: 1 to 4 HER2-amplified CTC) or in cohort “H” (high count: 5 or more HER2-amplified CTC). 14 patients (7L+7H) will be included in the first step. If needed, the second step will include 14 additional patients (7L+7H). Tumor response (per RECIST criteria) is the main objective of the trial.

Eligibility criteria: main criteria are HER2-negative metastatic breast cancer; measurable disease progressing after a first line treatment; PS 0-1; criteria related to T-DM1 treatment and ethics. Only patients with HER2-positive CTC will be treated by t-DM1.

Specific aim: this study will assess the response rate to T-DM1 in patients with HER2-amplified CTC and HER2-negative metastatic breast cancer, taking into account the number of HER2-amplified CTC detected (1-4 or 5+).

Statistical methods: To design this adaptive study, response rates were estimated to be H0 = 5% (no efficacy of T-DM1) and H1 = 25% (efficacy of T-DM1). After the first step (N = 7L and 7H patients): if no response is seen, the trial will be stopped, and considered as negative; if 3 or more responses are seen, we will conclude that the CTC FISH test is relevant to select patient for T-DM1 treatment, in either the L or/and H population, according to the observed pattern of responses; if 1 or 2 responses are observed, 14 more patients will be enrolled (7L+7H) in the second step of the trial. At the end of the second step, if 3 or less responses are observed, the trial will be considered as negative; if 4 or more responses are seen, we will conclude that the CTC FISH test is relevant to select patient for T-DM1 treatment, in either the L or/and H population, according to the observed pattern of responses. Based on the above-mentioned hypotheses and number of patients, the alpha risk was simulated to be of 6%, with a power of 94%.

Present accrual and target accrual: trial will start in summer 2013 in France. Up to 28 patients will be treated in this study.

Contact information: Francois-Clement Bidard, Institut Curie, Paris, France.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr OT1-1-10.

Abstract P2-11-16: Prospective comparison of prognostic factors in patients starting a third line of chemotherapy for metastatic breast cancer: An ancillary study to the CirCe01 trial

Background: Several prognostic factors and composite scores based on either patients general condition and/or usual blood analyses have been described in the setting of advanced metastatic cancers to estimate patients overall survival (OS). Over the past decade, circulating tumor cells (CTC) have been repeatedly reported as being a strong prognostic tool in metastatic breast cancer patients. We took the opportunity of the observational part of a prospective clinical trial (CirCe01, NCT01349842) that included 3rd line metastatic breast cancer patients to assess and compare several prognostic factors/scores and circulating tumor cell count.

Patients and Methods: Metastatic breast cancer patients were included before the start of a 3rd line chemotherapy at the Institut Curie, Paris, France. The following adverse prognostic factors were assessed prospectively and compared to overall survival: altered performance status (PS≥2), lymphopenia (<1,000 lymphocyte/microl), elevated CTC count (CellSearch, ≥5CTC/7.5ml), low albumin (<35g/l), elevated CA 15.3 (>30UI/ml), elevated CEA (>5ng/ml), elevated LDH (>50UI/l). Two composite scores were also evaluated: the Barbot score (combining Karnofsky index, number of metastases, albumin and LDH; Barbot JCO 2008) and the Prognostic Inflammatory and Nutritional Index (PINI; combining albumin, prealbumin, orosomucoid and C-reactive protein). Metastatic sites (liver, lung, bone) were also analyzed. Survival was analyzed by Kaplan-Meier curves; multivariate analysis was done using a Cox model.

Results: 56 patients have included prospectively and 36 of them (64%) died. CA 15.3 and CEA levels, lymphopenia and metastatic sites had no significant impact on OS in univariate analysis. The incidence of the significant prognostic markers (%), their correlations (p value) and impact (p value) on overall survival are shown.

Correlation and impact on overall survival of prognostic markersFactorIncidenceCorrel. with PS (p value)Correl. with Alb (p value)Correl. with LDH (p value)Correl. with Barbot (p value)Correl. with PINI (p value)Univ. OS (p value)CTC > = 545%NSNS<0.001NSNS0.004PS > = 214%-0.0020.04<0.0010.003<0.001Alb <3516%--NS<0.001<0.001<0.001LDH>50065%---0.05NS0.032Barbot score >316%----0.005<0.001PINI >1013%-----<0.001

In multivariable analysis, the three independent prognostic markers on OS were: elevated CTC count (p = 0.003, HR = 3.4 95% CI [1.5-7.7]), poor PS (p = 0.005, HR = 4.1 95% IC[1.5-11.3]) and low albumin (p<0.0001, HR = 11.3 95% IC[3.9-32.5]).

Discussion: CTC are an independent prognostic marker, even in advanced metastatic breast cancer. The disease aggressiveness being captured by the CTC count, usual clinical and biochemical tests appear to be sufficient to evaluate the patient prognosis, whereas more complex score (PINI, Barbot) appear to be of low interest.

Financed by: Ligue contre le cancer and PHRC 2009.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-11-16.

Abstract S6-07: Genomic characterisation of metastatic samples from breast cancer patients using next generation sequencing

Background: Although several studies have reported genomic characterisation of primary breast tumors, little is known about the genomic alterations of the metastatic tissues. Breast cancer patients who were prospectively enrolled in a trial (SAFIR01) underwent a biopsy of metastasis. The primary aim of this biopsy was to drive the treatment according to the results of whole genome CGH arrays and sanger sequencing on two genes (PIK3CA and AKT1). The results of the clinical trial were previously reported (André et al ASCO 2013). The secondary goal of the biopsies was to perform genomic characterisation of metastases in breast cancer patients. Here we report the analyses of such metastatic samples using next generation sequencing (NGS) approaches.

Patients and methods: Two approaches were applied. In order to describe the incidence of targetable genomic alterations, we performed in depth targeted sequencing on 100 genes (200x coverage) using Illumina HiSeq 2000 (DNA vision). This analysis was performed on 240 metastatic samples. The second approach was more exploratory and aimed at discovering new genes involved in the metastatic process and/or resistance to therapies. In order to achieve this goal, we performed whole exome sequencing in 100 pairs of metastatic tissue (100x) and normal DNA (Integragen Inc, Hiseq platform). Finally, phosphor-S6K staining was performed in 300 samples in order to explore the activation status of mTOR pathway in metastatic disease, and to correlate with genomic data.

Results: Targeted sequencing was performed on 240 metastatic samples in order to report the prevalence of targetable genomic alterations in metastatic breast cancer. Results are available for the first 159 samples. In addition to the already reported PIK3CA (26%) and AKT1 mutations (4%), NGS identified mutations of PTEN (4%), ERBB2 (2%), K-Ras (1%), ATM (2%), CDH1 (2%), GATA3 (2%), PTPN11 (1%), PTPRD (1%), ROS1 (1%). Results on the 81 samples, together with whole exome sequencing (n = 100) and phosphoproteins are being analysed and results will be available mid-november 2013.

Conclusion: This is the first large study that aims at defining the genomic landscape of metastatic samples. Results will provide insights into the prevalence of targetable genomic alterations in metastatic tissue, together with candidate genes involved in the metastatic process and resistance to therapies.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr S6-07.

Abstract A218: Pharmacokinetics of orally administered rucaparib in patients with advanced solid tumors

Background: Oral cancer therapies are often complicated by variable absorption leading to highly variable plasma pharmacokinetics (PK) and thus unpredictable toxicity and efficacy. Rucaparib, a poly (ADP-ribose) polymerase inhibitor (PARPi), is being developed for treatment of tumors associated with homologous recombination repair deficiency with a pre-specified target plasma trough level. While efficacy has been shown for PARPis, dose interruptions/reductions due to adverse events (AEs) are common for PARPis. Here, we report the PK results for oral rucaparib in patients and assess exposure predictability.

Methods: Rucaparib PK was studied in two Phase I studies. CO-338-010 (N=39) is an ongoing Phase I/II monotherapy study examining safety, PK, and preliminary efficacy of oral rucaparib administered continuously 40-500 mg once (qd) or 240-600 mg twice daily (bid) (NCT01482715). The effect of a high-fat meal on rucaparib PK was examined at 40 mg (N=3) and 300 mg (N=6). A4991014 (N=53) is an ongoing Phase I study currently assessing rucaparib in combination with carboplatin (CBDCA) (NCT01009190). Patients received lead-in oral rucaparib on Day -5 followed by CBDCA on Day 1 and oral rucaparib qd on Days 1-14 of every 21-day treatment cycle. Patients in earlier cohorts also had a single lead-in dose of intravenous rucaparib for calculating oral bioavailability. Plasma rucaparib levels were determined using a validated LC-MS/MS method.

Results: Rucaparib exhibited good oral absorption with a dose-independent oral bioavailability of 36% and median Tmax ranging from 1 to 6 hours. Exposure generally exhibited dose proportional kinetics up to 1200 mg daily dose (600 mg bid). The target trough level of 2 μM was achieved in 100% of patients (n=14) at ≥240 mg bid with low inter-patient variability (<4-fold) within each dose group. Steady state trough levels also exhibited low intra-patient variability (24% CV). No sporadically high exposures were observed. In the combination study, rucaparib PK at doses of 80 to 360 mg qd was not meaningfully altered by concomitant AUC3 to AUC5 CBDCA. Rucaparib half-life of ∼17 hours was independent of dose. There was no food effect; patients may take rucaparib on an empty stomach or with food. Overall variability of exposure was low, both intra- and inter- patient.

Conclusions: Rucaparib showed desirable dose- and time- independent PK with low inter- and intra- patient variability in exposure compared to published olaparib data. Predictable PK following oral dosing may lead to low rates of over- and under- dosing, potentially minimizing AEs associated with high unpredictable exposures, an important attribute for maintenance therapy. Rucaparib's low inter-patient variability is beneficial for uniform flat dosing strategies. This will be explored in the two upcoming studies, ARIEL2 and ARIEL3.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A218.

Citation Format: Geoffrey Shapiro, Rebecca Kristeleit, Mark Middleton, Howard Burris, L. Rhoda Molife, Jeff Evans, Richard Wilson, Patricia LoRusso, James Spicer, Veronique Dieras, Manish Patel, Erin Dominy, Dayna Simpson, Heidi Giordano, Andrew R. Allen, Sarah S. Jaw-Tsai, Ruth Plummer. Pharmacokinetics of orally administered rucaparib in patients with advanced solid tumors. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A218.

Array CGH and DNA sequencing to personalize targeted treatment of metastatic breast cancer (MBC) patients (pts): A prospective multicentric trial (SAFIR01)

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Background: The aim of the present study was to profile the metastatic lesion of pts using high throughput technologies, and to treat them accordingly. Methods: SAFIR01 trial aimed to include 400 pts with MBC, selected for not presenting a progressive disease at the time of biopsy. A biopsy was done in a metastatic site. DNA was extracted if the tumor contained >50% cancer cells, and sent to one of the 5 genomic centers who performed array CGH (copy number changes) and sanger sequencing on PIK3CA (exon 10/21) and AKT1 (exon 3). A targeted therapy matched to the genomic alteration was expected to be proposed at the time of progressive disease. The primary endpoint was the % of pts who received a targeted therapy according to the genomic alteration. Results: A biopsy of metastatic site was done successfully in 408 out of the 423 included pts. Biopsy was complicated by a serious adverse event in 9 pts. A discrepancy between primary and metastatic lesion was observed in 8% and 19% of pts for Her2 and HR. Array CGH and sequencing were successfully obtained in 277 (68%) and 295 (72%) pts. The main reason for failure of genomic test was the low cellularity (n=93). A targetable genomic alteration was identified in 204 pts. The most frequent genomic alterations were PIK3CA mutations, CCND1, FGF4 and FGFR1 amplifications. 76 pts presented a rare targetable genomic alteration (<5%), including AKT1 mutations, EGFR, FGFR2, PIK3CA, MDM2 amplifications. Early Feb 2013, 4 6 out of 277 pts with genomic analyses (17%) had received a targeted therapy matched to the genomic alteration, covering twelve different targets. Updated results on number of pts treated, together with efficacy data will be presented. Next generation sequencing on metastatic lesions is ongoing and results will be presented. Conclusions: This trial evaluated the concept of personalized medicine for MBC and provided a large scale genomic analysis of metastatic tissue. This study suggests that assessing the biology of metastatic tissue could allow driving pts to targeted therapy. A randomized trial (SAFIR02) testing this approach is expected to start during summer 2013. Clinical trial information: NCT01414933.

A randomized, multicenter, double-blind phase III study of palbociclib (PD-0332991), an oral CDK 4/6 inhibitor, plus letrozole versus placebo plus letrozole for the treatment of postmenopausal women with ER(+), HER2(–) breast cancer who have not received any prior systemic anticancer treatment for advanced disease

TPS652

Background: Palbociclib (PD-0332991) is an orally bioavailable selective inhibitor of CDK4/6 that prevents DNA synthesis by prohibiting progression of the cell cycle from G1 to S phase. In a randomized phase II trial comparing palbociclib (PD-0332991) plus letrozole (P + L) to letrozole (L) in postmenopausal women with ER(+), HER2(–) advanced breast cancer (ABC) who had not received any prior systemic anticancer therapy for their advanced disease, P + L demonstrated significantly longer progression-free survival (PFS) vs L (26.1 vs 7.5 mo; HR = 0.37, P < .001) and was generally well tolerated, with uncomplicated neutropenia as the most frequent adverse event (Finn et al SABCS 2012). Methods: Based on phase II data, a global, randomized, double-blind, phase III clinical trial was designed to demonstrate that P + L provides superior clinical benefit compared with L + placebo in postmenopausal women with ER(+), HER2(–) ABC who have not received any prior systemic therapy for their advanced disease. The study aims to assess whether P + L improves median PFS over L at HR of at least 0.7. Approximately 450 eligible patients with locoregionally recurrent or metastatic, pathologically confirmed ABC who are candidates to receive L as first-line treatment for their advanced disease will be randomized 2:1 to receive either P (125 mg QD 3 wk on, 1 wk off) + L (2.5 mg QD) or L (2.5 mg QD) + placebo. Patients who received anastrozole or letrozole as part of their (neo)adjuvant regimen are eligible if their disease progressed more than 12 months from completion of adjuvant therapy. Tumor tissue is required for participation. Secondary endpoints include overall survival, objective response, duration of response, clinical benefit, safety and tolerability, and patient-reported outcomes of health-related quality of life and disease- or treatment-related symptoms. Clinical trial information: NCT01740427.

PIKHER2: A phase Ib/II study evaluating safety and efficacy of oral BKM120 in combination with lapatinib in HER2-positive, PI3K-activated, trastuzumab-resistant advanced breast cancer

TPS663

Background: Phosphatidylinositol-3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR)-pathway is frequently activated in HER2-positive breast cancer and may play a major role in resistance to trastuzumab. BKM120 is an oral pan-class I PI3K inhibitor with potent and selective activity against wild-type and mutant PI3K p110α. PIKHER2 study will evaluate safety and efficacy of oral, daily lapatinib-BKM120 combination in HER2-positive, trastuzumab-resistant advanced breast cancer (ABC) with activated PI3K/AKT/mTOR pathway. Methods: This open label, single arm, multi-center study includes a phase Ib dose-escalation part and a phase II expansion part at the recommended dose (RP2D). Primary objectives include determination of the maximum-tolerated dose (MTD) of BKM120 in combination with lapatinib in trastumuzab-resistant HER2-positive ABC (phase Ib part) and evaluation of the activity of BKM120-lapatinib combination at RP2D as measured by objective response rate (ORR) in patients with activated PI3K/AKT/mTOR pathway, as defined by PTEN-negative by IHC and/or somatic mutations (exons 9 and 20) of PIK3CA and/or overexpression of phospho-AKT by IHC (phase II part). Secondary objectives include safety and tolerability of the combination, clinical benefit and progression-free survival, pharmacokinetic profiles, biological and pharmacodynamic correlates. Main eligibility criteria are PS ≤ 1, HER2-positive ABC resistant to trastuzumab, documented activated PI3K/AKT/mTOR pathway (phase II part only). A modified CRM using an adaptive Bayesian model guides the dose escalation of both agents with a maximum of 24 patients planned to be enrolled in phase Ib part. Efficacy will be tested according to a standard 2-stage Simon design under the following unacceptable and desirable hypotheses: H0, ORR <= 10% (unacceptable rate) vs. H1, ORR >=30% (desirable rate). A maximum of 35 patients with activated PI3K/AKT/mTOR pathway is planned to be enrolled in phase II part with an interim look after 18 evaluable patients will have been recruited. Clinical trial information: NCT01589861.

A French prospective pilot study for identifying dihydropyrimidine dehydrogenase (DPD) deficiency in breast cancer patients (pts) receiving capecitabine (cap)

e13519

Background: For fluoropyrimidines, and especially cap, Health Authorities point out that DPD deficiency confers a significant risk of major toxicity (tox). Identification of at-risk pts is thus relevant. This multicentric prospective study of the French GPCO group (Groupe de Pharmacologie Clinique Oncologique, Unicancer) evaluated the sensitivity, specificity and predictive values of DPD phenotyping and genotyping for predicting severe cap-related tox in metastatic breast cancer pts. Methods: 303 pts were included (15 institutions), 88% received cap as monotherapy, 28% were treated as first line (mean dose at 1st cycle 1957 mg/m2/d). Pre-treatment dihydrouracil (UH2) and uracil (U) plasma concentrations were measured in 286 pts (HPLC assay). DPD genotyping (IVS14+1G>A, 2846A>T, 1679T>G, 464T>A) was done on 281 pts. Severe tox (G3-4 CTCAE v3 criteria) was measured over cycles 1-2. Results: Grade 3-4 tox (diarrhea, vomiting, hematoxicity, hand-foot syndrome) was observed in 19.6% of pts (one toxic death). A marked trend for higher U (median 12.7 vs 10.2 ng/ml, p=0.014) and UH2 (median 110 vs 93 ng/ml, p=0.011) concentrations was observed in pts developing severe tox vs those who didn’t. However, ROC curves showed that these differences were too small for use as reliable tox predictors. The distribution of UH2/U ratio was similar between pts with or without tox (median 9.1 vs 9.6, respectively, p=0.80). The patient with toxic death had a UH2/U ratio of 6.5 and U concentration of 17 ng/ml. Among the 7 pts with a DPD mutation (3 pts IVS14+1, 3 pts 2846A>T, one 1679T>G, all heterozygous), 5 developed severe tox (including toxic death, 2846A>T), one did not, and the last one was not documented. Relative risk for developing severe tox was 4.60 in mut pts vs wt pts (95%CI 2.95-7.16, p=0.001); positive and negative predictive values were 83.3% and 81.9%, respectively; specificity was 99.5% and sensitivity was 9.8%. Conclusions: These data point out that breast cancer pts harbouring a DPD variant allele are candidate to develop severe, up to lethal, cap-related tox. In contrast, pre-treatment UH2/U ratio and U measurements are not reliable predictors of cap tox. Clinical trial information: Eudract 2008-004136-20.

Trastuzumab (T) and everolimus (E) pharmacokinetics (PK) in HER2 positive (+) primary breast cancer (BC) patients (pts): Unicancer RADHER trial results

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Background: T has greatly modified the prognosis of HER2+ BC, but few studies have analyzed its PK. The RADHER study evaluated the interest of adding E to T as preoperative therapy for primary HER2+ BC. It also aimed at describing the PK of T and studying the impact of E with T in primary BC. Methods: Eligible pts with HER2+ operable primary BC were randomized to receive T alone (loading dose 4 mg/kg, then 2 mg/kg/week (W)) or T + E (10 mg/day (D)) for a 6-W pre-operative treatment. Blood samples were collected to measure T and E concentrations. For T, plasma samples were collected in all pts before each infusion, and at Hour (H) 1, D1, D3, W1, W2, W4, W8 and W12 after the last infusion. E concentrations were determined on whole blood collected at H0, H0.5, H1, H2, H4, H6, H12 and H24 after the first T infusion, and again after the last E intake. T and E PK were described using population compartment analyses. Results: From 82 pts randomized, 79 were evaluable for T and 22 for E PK. Mean estimated PK parameters of T were (interindividual coefficient of variation %): central (Vc) and peripheral (Vp) volumes of distribution = 2 L (24%) and 1.3 L (39%), systemic (CL) and intercompartment (Q) clearances = 0.22 L/day (19%) and 0.36 L/day, respectively. Vc increased with body weight and decreased with age, while CL increased with body weight and with tumor volume. Elimination half-life was 11 days, a value lower than that previously reported in metastatic BC (28 days). E PK was best described by a two-compartment model. Mean estimated PK parameters (RSE%) of E were: CL = 3.96 L/h (22%), Q = 29.1 L/h (7%), Vc = 119 L (11%), Vp = 1530 L (24%). E did not influence T PK. E PK was similar to that previously reported in other indications. Conclusions: This is the first study describing the PK of T and E in primary BC. Notably, T CL increases with tumor volume and the elimination half-life is only 11 days, lower than expected from previous results in metastatic BC. The differences in PK between primary and metastatic BC might lead to take a second look at trastuzumab dose regimen in primary BC. Clinical trial information: NCT00674414.

Long-term prognostic performance of Ki67 rate in early stage, pT1-pT2, pN0, invasive breast carcinoma

BACKGROUND

Molecular signatures may become of use in clinical practice to assess the prognosis of breast cancers. However, although international consensus conferences sustain the use of these new markers in the near future, concerns remain about their degree of discordance and cost-effectiveness in different international settings. The present study aims to validate Ki67 as prognostic factor in a large cohort of early-stage (pT1-pT2, pN0) breast cancer patients.

METHODS

456 patients treated in 1995-1996 were identified in the Institut Curie database. Ki67 (MIB1) was retrospectively assessed by immunohistochemistry for all cases. The prognostic value of this index was compared to that of histological grade (HG), Estrogen receptor (ER) and HER2 status. Distant disease free interval, loco-regional recurrence, time-lapse from first metastatic diagnosis to death were analyzed.

RESULTS

All 456 patients were treated by lumpectomy plus axillary dissection and radiotherapy. 27 patients (5.9%) received systemic treatment. Tumors were classified as HG1 in 35%, HG2 in 42% and HG3 in 23% of cases. ER was expressed in 86% of the tumors, HER2 in 5% and 14% were triple negative. The median follow-up was 151 [5-191] months. Distant and loco-regional disease recurrences were observed in 16% and 18%, respectively. High (>20%) Ki67 rate [HR = 3 (1.8-4.8), p<10e-06] and HG3 [HR = 4.4 (2.2-8.6), p = 0.00002] were associated with an increased rate of distant relapse. In multivariate analysis, the Ki67 remained the only significant prognostic factor in the subgroups of ER positive HER2 negative [HR = 2.6 (1.5-4.6), p = 0.0006] and ER positive HER2 negative HG2 tumors [HR = 2.2 (1.01-4.8), p = 0.04].

CONCLUSIONS

We validate the prognosis value of the Ki67 rate in small size node negative breast cancer. We conclude that Ki67 is a potential cost-effective decision marker for adjuvant therapy in early-stage HG2, pT1-pT2, pN0, breast cancers.

Phase I study of humanized monoclonal antibody AVE1642 directed against the type 1 insulin-like growth factor receptor (IGF-1R), administered in combination with anticancer therapies to patients with advanced solid tumors

BACKGROUND

Type 1 insulin-like growth factor receptor (IGF-1R) mediates resistance to chemotherapy and targeted agents. This study assessed the safety, pharmacokinetics (PK), and tolerability of humanized IGF-1R antibody AVE1642 with other cancer treatments.

PATIENTS

Patients with advanced solid tumors received three weekly AVE1642 dosed at 6 mg/kg, chosen following previous study, with 75 (cohort A) or 100 mg/m(2) (B) docetaxel, 1250 mg/m(2) gemcitabine/100 mg erlotinib (C1), or 60 mg/m(2) doxorubicin (D1). Blood samples were assayed for PK, IGFs, and IGF-BP3.

RESULTS

Fifty-eight patients received 317 AVE1642 infusions. The commonest adverse events were diarrhea (37/58 patients), asthenia (34/58), nausea (30/58), and stomatitis (21/58). Dose-limiting toxic effects in cohorts C1 (diarrhea) and D1 (neutropenia) prompted addition of cohorts C2 (1000 mg/m(2) gemcitabine/75 mg erlotinib) and D2 (50 mg/m(2) doxorubicin). Grade 3-4 hyperglycemia (three cases) accompanied steroid premedication for docetaxel administration. No PK interactions were detected. There were three partial responses in cohorts B (melanoma) and C (leiomyosarcoma, two cases) and 22 stabilizations ≥12 weeks, giving a control rate of 25/57 (44%). On treatment IGF-II rose by 68 ± 25 ng/ml in patients discontinuing treatment <12 weeks, and fell by 55.5 ± 21 ng/ml with disease control (P < 0.001).

CONCLUSION

AVE1642 was tolerable with 75-100 mg/m(2) docetaxel and 1000 mg/m(2) gemcitabine/75 mg erlotinib, achieving durable disease control in 44%, with an association between IGF-II and response.

Abstract P2-01-13: Prognostic value of Circulating Tumor Cells count at progressive disease after first line chemotherapy metastatic breast patients in a large prospective multicenter trial including serum tumor markers (IC 2006–04 study)

Background: The IC 2006–04 study included prospectively 267 metastatic breast cancer patients before the start of first line chemotherapy. We previously reported and confirmed the prognostic and predictive of CTC counts before the start of treatment and after 3–4 & 6–9 weeks of treatment (Pierga, JY SABCS 2010, Ann Oncol 2012). We report here the results of the last CTC count performed at tumor progression (i.e. end of first line chemotherapy).

Methods: Patients were included in the study from 06/07 to 9/09. CTC were counted by the CellSearch® system at tumor progression (clinical and/or radiological progression).

Results: 211 patients experienced a tumor progression at time of final data analysis and the planned CTC count has been performed in 61 patients. High CTC count (≥5 CTC/7.5ml) at progression was observed in 22 patients (36%) and was associated with elevated Cyfra 21–1 and ALP and was not associated with elevated CEA, CA 15–3, LDH, the elapsed progression-free survival, the onset of new metastasis. No CTC was detected at tumor progression in the 5 patients with HER2+ disease, in line with our previous results. The prognostic markers for overall survival at tumor progression were high CTC count (median overall survival 8 vs 19 months, p = .0006) and elevated Cyfra 21–1 (p = .001). Other serum markers (CEA, CA15-3, ALP, LDH) and tumor subtypes had no prognostic value at univariate analysis. At multivariate analysis, the two prognostic factors for overall survival were high CTC count (RR = 2.3 p = 0.03) and elevated Cyfra 21–1 (RR = 3.6 p = 0.02).

Conclusion: In the prospective IC 2006–04 study, among the different markers tested at tumor progression during the first line chemotherapy for metastatic breast cancer, high CTC count and elevated Cyfra 21–1 levels were the only two independent prognostic markers for overall survival.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-01-13.

Primary results from EMILIA, a phase III study of trastuzumab emtansine (T-DM1) versus capecitabine (X) and lapatinib (L) in HER2-positive locally advanced or metastatic breast cancer (MBC) previously treated with trastuzumab (T) and a taxane

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Background: T-DM1 is an antibody-drug conjugate comprising T, a stable linker, and the potent cytotoxic agent DM1; it incorporates the antitumor activities of T and the HER2-targeted delivery of DM1. Methods: EMILIA is a randomized study of T-DM1 vs XL, the only approved combination for T-refractory HER2+ MBC. Patients (pts) received T-DM1 (3.6 mg/kg IV q3w) or X (1,000 mg/m2PO bid, days 1–14 q3w) + L (1,250 mg PO daily) until progressive disease (PD) or unmanageable toxicity. Pts had confirmed HER2+ MBC (IHC3+ and/or FISH+), and prior therapy with T and a taxane. Primary end points were PFS by independent review, OS and safety. An interim OS analysis was planned at the time of the final PFS analysis. Results: 991 pts were enrolled; 978 received treatment. Median (med) durations of follow-up were 12.9 (T-DM1) and 12.4 (XL) months (mo). Baseline demographics, prior therapy and disease characteristics were balanced. There was a significant improvement in PFS favoring T-DM1 (med 9.6 vs 6.4 mo; HR=0.650 [95% CI, 0.549–0.771]; p < .0001). The med T-DM1 OS was not reached vs 23.3 mo (HR=0.621 [95% CI, 0.475–0.813]; p =.0005); the interim efficacy boundary was not crossed (HR= 0.617; p =.0003). T-DM1 was well tolerated with no unexpected safety signals. The most common Grade ≥3 adverse events (AEs) per treatment were for T-DM1: thrombocytopenia (12.9% vs 0.2%), increased AST (4.3% vs 0.8%), and increased ALT (2.9% vs 1.4%); for XL: diarrhea (20.7% vs 1.6%), palmar plantar erythrodysesthesia (16.4% vs 0) and vomiting (4.5% vs 0.8%). The table lists other end points. Conclusions: T-DM1 conferred a significant and clinically meaningful improvement in PFS compared with XL. Other end points support T-DM1 as an active and well-tolerated novel therapy for HER2+ advanced BC. [Table: see text]

Phase I dose-escalation study of the safety, pharmacokinetics, and pharmacodynamics of the MEK inhibitor RO4987655 (CH4987655) in patients with advanced solid tumors

PURPOSE

This phase I study of the mitogen-activated protein/extracellular signal-regulated kinase inhibitor RO4987655 (CH4987655) assessed its maximum tolerated dose (MTD), dose-limiting toxicities (DLT), safety, pharmacokinetic/pharmacodynamic profile, and antitumor activity in patients with advanced solid tumors.

PATIENTS AND METHODS

An initial dose escalation was conducted using a once-daily dosing schedule, with oral RO4987655 administered at doses of 1.0 to 2.5 mg once daily over 28 consecutive days in 4-week cycles. Doses were then escalated from 3.0 to 21.0 mg [total daily dose (TDD)] using a twice-daily dosing schedule.

RESULTS

Forty-nine patients were enrolled. DLTs were blurred vision (n = 1) and elevated creatine phosphokinase (n = 3). The MTD was 8.5 mg twice daily (TDD, 17.0 mg). Rash-related toxicity (91.8%) and gastrointestinal disorders (69.4%) were the most frequent adverse events. The pharmacokinetic profile of RO4987655 showed dose linearity and a half-life of approximately 4 hours. At the MTD, target inhibition, assessed by suppression of extracellular signal-regulated kinase phosphorylation in peripheral blood mononuclear cells, was high (mean 75%) and sustained (90% of time >IC(50)). Of the patients evaluable for response, clinical benefit was seen in 21.1%, including two partial responses (one confirmed and one unconfirmed). 79.4% of patients showed a reduction in fluorodeoxyglucose uptake by positron emission tomography between baseline and day 15.

CONCLUSION

In this population of heavily pretreated patients, oral RO4987655 showed manageable toxicity, a favorable pharmacokinetics/pharmacodynamics profile, and promising preliminary antitumor activity, which has been further investigated in specific populations of patients with RAS and/or RAF mutation driven tumors.

Primary results from EMILIA, a phase III study of trastuzumab emtansine (T-DM1) versus capecitabine (X) and lapatinib (L) in HER2-positive locally advanced or metastatic breast cancer (MBC) previously treated with trastuzumab (T) and a taxane

LBA1

Background: T-DM1 is an antibody-drug conjugate comprising T, a stable linker, and the potent cytotoxic agent DM1; it incorporates the antitumor activities of T and the HER2-targeted delivery of DM1. Methods: EMILIA is a randomized study of T-DM1 vs XL, the only approved combination for T-refractory HER2+ MBC. Patients (pts) received T-DM1 (3.6 mg/kg IV q3w) or X (1000 mg/m2 PO bid, days 1–14 q3w) + L (1,250 mg PO daily) until progressive disease (PD) or unmanageable toxicity. Pts had confirmed HER2+ MBC (IHC3+ and/or FISH+), and prior therapy with T and a taxane. Primary end points were PFS by independent review, OS and safety. An interim OS analysis (efficacy boundary: HR= 0.617; p=0.0003) was planned at the time of the final PFS analysis. Results: 991 pts were enrolled; 978 received treatment. Median (med) durations of follow-up were 12.9 (T-DM1) and 12.4 (XL) months (mo). Baseline demographics, prior therapy and disease characteristics were balanced. There was a significant improvement in PFS favoring T-DM1 (med 9.6 vs 6.4 mo; HR=0.650 [95% CI, 0.549–0.771]; p <0.0001). The med T-DM1 OS was not reached vs 23.3 mo (HR=0.621 [95% CI, 0.475–0.813]; p=0.0005); the interim efficacy boundary was not crossed. T-DM1 was well tolerated with no unexpected safety signals. The most common grade ≥3 adverse events (AEs) per treatment were for T-DM1: thrombocytopenia (12.9% vs 0.2%), increased AST (4.3% vs 0.8%), and increased ALT (2.9% vs 1.4%); for XL: diarrhea (20.7% vs 1.6%), palmar plantar erythrodysesthesia (16.4% vs 0) and vomiting (4.5% vs 0.8%). The table lists other end points. Conclusions: T-DM1 conferred a significant and clinically meaningful improvement in PFS compared with XL. Other end points support T-DM1 as an active and well-tolerated novel therapy for HER2+ advanced BC. [Table: see text]

HIT: A multicenter phase I-II study of trastuzumab administered by intrathecal injection for leptomeningeal meningitis of HER2+ metastatic breast cancer

TPS662

Background: Leptomeningeal metastases (LM) are commonly associated with breast cancer (BC), announcing short term prognosis that intrathecal (IT) chemotherapy poorly modifies. Incidence is particularly marked in HER2+ tumours. With the better control of extra-cerebral disease and prolonged survival yielded by intra-venous (IV) trastuzumab (T), the main hypothesis is that intra-cerebral recurrences are not reached by this high molecular weight (148 kD) monoclonal antibody. Analyses performed in cerebrospinal fluid (CSF) following IV T have shown low T levels, suggesting that LM of HER2+ BC would remain potentially sensitive to anti-HER2 agents as long as they could by-pass the meningeal blood brain barrier. Intraventricular (via Ommaya port) or IT administration of T would allow keeping control on LM progression through high T therapeutic concentrations in CSF. This prospective trial is the first phase I-II study sponsored by Institut Curie to investigate the safety and efficacy of the IT administration of T for HER2+ LM BC. Methods: Eligible patients must be 18+, have a diagnosis of LM either on CSF with HER2+ cytology or on clinical/MRI pictures of meningitis, and normal end-organ functions. The phase I cohort investigates the maximum tolerated dose (MTD) and recommended dose of T given weekly IT (or via Ommaya port) + hemisuccinate hydrocortisone 25 mg, while aiming at yielding a T target-concentration in CSF close to the plasma one (30 µg/mL) obtained with standard IV schedule. The MTD is defined as the highest dose level (DL) tested with ≥2 dose-limiting toxicity (DLT, any grade ≥3 NCI CTCAE v4.0 attributed to T) observed in ≤6 patients (3+3 Fibonacci dose escalation design, 4 DL 30-150 mg) with a maximum of 24 patients. The phase II cohort will investigate the efficacy of the recommended dose (DLMTD-1) defined in cohort I on neurological progression-free survival at 2 months, in ≤19 patients. Secondary endpoints include CSF and MRI response, quality of life, FCGR3A influence, and comparative CSF/plasma pharmacokinetics. Since study activation in May 2011, 5 patients have been included at DL1, 3 being evaluable for DLT. DL2 is now open for accrual.

Primary results from EMILIA, a phase III study of trastuzumab emtansine (T-DM1) versus capecitabine (X) and lapatinib (L) in HER2-positive locally advanced or metastatic breast cancer (MBC) previously treated with trastuzumab (T) and a taxane

LBA1

The full, final text of this abstract will be available at abstract.asco.org at 12:01 AM (EDT) on Sunday, June 3, 2012, and in the Annual Meeting Proceedings online supplement to the June 20, 2012, issue of Journal of Clinical Oncology. Onsite at the Meeting, this abstract will be printed in the Sunday edition of ASCO Daily News.