Present and future breast cancer management--bench to bedside and back: a positioning paper of academia, regulatory authorities and pharmaceutical industry

Insights into tumour biology of breast cancer have led the path towards the introduction of targeted treatment approaches; still, breast cancer-related mortality remains relatively high. Efforts in the field of basic research revealed new druggable targets which now await validation within the context of clinical trials. Therefore, questions concerning the optimal design of future studies are becoming even more pertinent. Aspects such as the ideal end point, availability of predictive markers to identify the optimal cohort for drug testing, or potential mechanisms of resistance need to be resolved. An expert panel representing the academic community, the pharmaceutical industry, as well as European Regulatory Authorities met in Vienna, Austria, in November 2012, in order to discuss breast cancer biology, identification of novel biological targets and optimal drug development with the aim of treatment individualization. This article summarizes statements and perspectives provided by the meeting participants.

Abstract P2-16-23: The ENCHANT-1 trial (NCT01677455): An open label multicenter phase 2 proof of concept study evaluating first line ganetespib monotherapy in women with metastatic HER2 positive or triple negative breast cancer (TNBC)

Background: Hsp90 is a molecular chaperone protein required for the stabilization and activation of many proteins, referred to as Hsp90 ‘clients’, such as HER2, HIF1-a, EGFR, ER, PI3K, AKT, P53 and VEGFR. The drug candidate, ganetespib is a novel triazolone inhibitor of Hsp90, with over 700 patients treated to date. Ganetespib has shown activity in preclinical models of HER2+, ER+/PR+ and TNBC. Early clinical trials documented ganetespib single agent activity in heavily pretreated HER2+ and TNBC patients. Ganetespib has been well tolerated in clinical trials with a favorable safety profile. This efficacy-screening study is designed to provide further evidence of ganetespib activity and identify potentially predictive biomarkers in metastatic breast cancer (BC).

Methods: The ENCHANT-1 Trial is an international, first-line 2-cohort Phase 2 study in BC patients: Cohort A, HER2 amplified (n = 35), and Cohort B, TNBC (n = 35). Patients who present with previously untreated metastatic disease are eligible for treatment with ganetespib at 150 mg/m2 twice weekly on 3 out of 4 wks, for a total of up to 12 wks. Primary endpoint: ORR assessed using RECIST1.1 criteria. Key secondary endpoints include metabolic response as assessed by PET/CT at wk 3 utilizing modified EORTC criteria. Disease progression (PD) at wk 3 by PET imaging indicates discontinuation of study therapy, and is performed to quickly offer patients with metabolic PD a standard of care treatment.

The study is designed as Simon 2-stage requiring at least one OR in 15 patients for the respective cohort to expand to 35 patients. A Steering Committee is established to oversee the overall study and review the interim results.

Results: The study was initiated in 23 centers globally. At the time of submission, a total of 17 patients had been enrolled; TNBC (n = 15) and HER2 (n = 2). Here we report the interim analysis in the TNBC cohort. The median age was 54 years (range 30 -77) with ECOG PS 0 (n = 7/15). Most patients (n = 9) presented with de novo metastatic disease. 5 patients were not evaluable for PET assessment (3 had not yet reached wk 3 and 2 withdrawn before wk 3 for clinical progression), and 9 patients were not evaluable for objective response at wk 6 (3 withdrawn before or at wk 3 for clinical progression and 6 had not yet reached wk 6 evaluation). In the 10 patients with evaluable PET imaging, 9 patients achieved metabolic (m) response (2 mPR, 4 mSD with dominant tumor shrinkage and 3 SD) and one patient with mPD. In the 6 patients evaluable for OR at wk 6, one patient achieved PR, 2 SD and 3 PD. Treatment with ganetespib was well tolerated; the most common AEs were mild or moderate diarrhea (8/15, 53%), fatigue (5/15, 33%), decreased appetite (4/15, 27%), insomnia (4/15, 27%), and nausea (4/15, 27%).

Conclusion: Ganetespib single agent was generally well tolerated and showed anti-tumor activity TNBC patients as early as 3 weeks following treatment. PET seems to be a good tool to screen antitumor activity of new agents in early settings rather that in heavily pretreated patients. The TNBC cohort has met the protocol criteria for proceeding to stage 2.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-16-23.

Abstract P3-13-04: Effect of age on tolerability and efficacy of eribulin and capecitabine in patients with metastatic breast cancer treated in study 301

Background:

The Phase III trial (NCT00337103) compared eribulin (E) with capecitabine (C) in patients (pts) with metastatic breast cancer (MBC) in the 1st-, 2nd-, and 3rd-line setting. Median overall survival (OS) was 15.9 and 14.5 months (HR 0.88; 95% CI 0.77, 1.00; P = 0.056) and median progression-free survival (PFS) was 4.1 and 4.2 months (HR 1.08; 95% CI 0.93, 1.25; P = 0.30) for E and C, respectively. This analysis compares toxicity and efficacy of E and C in relation to age.

Material and methods:

In this post-hoc exploratory analysis, the effect of age on the incidence of adverse events (AEs), OS, PFS, and objective response rate (ORR) with E and C were analyzed for two age groups: ≤65 years (E, n = 468; C, n = 491) and >65 years (E, n = 86; C, n = 57). For OS and PFS, analyses were stratified by HER2 and geographic region.

Results:

With increasing age, the proportion of pts with worse performance status (PS ≥1: 54.5% vs 69.2% for ≤65 and >65 years, respectively), ER+ (47.4% vs 57.3%), and PgR+ MBC (41.3% vs 45.5%) increased, and the proportion with triple-negative MBC decreased (26.6% vs 20.3%). With both treatments, AEs were reported in a higher proportion of pts in the older age group, this becoming more apparent for grade 3+ AEs (E: 64.6% vs 70.2%, and C: 45.0% vs 54.4% for ≤65 and >65 respectively). With E, there was a trend for increased incidence of grade 3/4 neutropenia (45.0% vs 50.0%) and leukopenia (13.7% vs 22.6%) but, in contrast, decreased peripheral sensory neuropathy (3.9% vs 1.2%) with increasing age. For C, there was a trend for increased palmar-plantar erythrodysethesia syndrome (total: 44.4% vs 50.9%; grade 3/4: 14.1% vs 17.5%), and grade 3/4 fatigue (1.8% vs 7.0%) and diarrhea (4.7% vs 10.5%) with increasing age; emesis and nausea were similar for both age groups. Dose adjustments due to AEs with E were slightly higher in the older age group: withdrawals 7.4% vs 10.7%; dose reductions 31.1% vs 36.9%; and dose delays 30.9% vs 36.9%. With C, there was a trend for an increased incidence of withdrawals (9.2% vs 21.1%) and dose delays (34.2% vs 49.1%) due to AEs with increasing age: the incidence of dose reductions was slightly higher in the older age group (31.3% vs 36.8%). In an unadjusted analysis, a trend for improved OS with E vs C was observed in both subgroups (≤65 years: median 15.8 vs 14.5 months; HR 0.90; 95% CI 0.78, 1.04; P = 0.16, and >65 years: median 18.4 vs 14.1 months; HR 0.74; 95% CI 0.50, 1.12; P = 0.16). PFS and ORR for E and C were: median PFS: E, 4.0 and 5.4 months; C, 4.2 and 5.9 months; ORR: E, 10.9% and 11.6%; C, 11.6% and 10.5%, in the ≤65 and >65 groups respectively.

Conclusions:

This exploratory and unadjusted analysis suggests a trend for improved OS with E in both younger and older pts with MBC. With both treatments there was a suggestion that AEs were reported in a higher proportion of pts in the older age group, this becoming more apparent for grade 3+ events. Specifically, these data suggest an increased incidence of grade 3/4 diarrhea, dose delays, and study withdrawal due to AEs in pts treated with C, and potentially suggest that with E there may be less difference between the AE profile in younger vs older pts than with C.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-13-04.

Abstract P2-16-04: A phase 2 study of ridaforolimus (RIDA) and dalotuzumab (DALO) in estrogen receptor positive (ER+) breast cancer

Background: Preclinical studies indicate that the dual inhibition of IGFR and mTOR may be additive or synergistic and abrogates the feedback activation of AKT due to rapamycin analog mTOR inhibitors. A phase 1 study of the mTOR inhibitor RIDA and the anti-IGFR antibody DALO demonstrated that the combination was feasible and well-tolerated at doses that were nearly those used for the two single agents. The dose limiting toxicity was stomatitis, similar to RIDA monotherapy. Preliminary signals of anti-tumor activity, including partial responses and prolonged progression free survival (PFS), were observed in ER+ advanced breast cancer (ABC), especially in high proliferation tumors (Ki67 ≥15%). Methods: The trial was a multi-center, international randomized study with PFS as the primary endpoint. Key eligibility included ABC with prior treatment with a non-steroidal aromatase inhibitor. The original phase 2 study design was a two-part, adaptive design intended to first test the combination of RIDA (30 mg by mouth daily for 5 out of every 7 days), -DALO (10 mg/kg IV weekly) against a standard agent, exemestane in Part A. Patients were stratified into high and low proliferation strata based on baseline Ki67. Following a demonstration of PFS benefit of the combination in Part A, Part B was intended to show the PFS benefit of the combination over each single agents by comparing RIDA-DALO to RIDA and DALO. Results: The study was initiated in October 2011. Accrual was suspended after the first 66 patients were randomized due to a higher than expected rate of stomatitis in the RIDA-DALO arm. Preliminary data indicated an overall incidence of any grade stomatitis was 68% (22/33 pts), and of grade 3 stomatitis was 35% (11/33 pts). In an effort to identify a more tolerable regimen, the study was amended to eliminate Part B and to evaluate two sequential reduced dose RIDA-DALO cohorts in a non-randomized design: 20mg and 10mg for 5 out of every 7 days. The dose of DALO was unchanged. Preliminary safety results of overall and grade 3 stomatitis in the 20 mg were 81.5% (22/27 pts) and 37% (10/27 pts), respectively. Although the incidence of overall stomatitis in the 10 mg cohort remained high, 88% (22/25 pts), grade 3 stomatitis was dramatically reduced to 8% (2/25 pts). Conclusion: Preliminary evaluation of safety from this phase 2 study demonstrates that the previously recommended phase 2 dose of RIDA-DALO was not tolerable. However lower doses of RIDA (10 mg) in combination with DALO appeared to be tolerable with markedly reduced rates of grade 3 stomatitis. Final results of efficacy, safety and RNA profiling analysis from the two RIDA-DALO dose cohorts as well as from the randomized portion of the study will be available at the time of the meeting.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-16-04.

Phase I trial combining temozolomide plus lapatinib for the treatment of brain metastases in patients with HER2-positive metastatic breast cancer: the LAPTEM trial

BACKGROUND

Brain metastases (BMs) pose a clinical challenge in breast cancer (BC). Lapatinib or temozolomide showed activity in BM. Our study assessed the combination of both drugs as treatment for patients with HER2-positive BC and BM.

METHODS

Eighteen patients were enrolled, with sixteen of them having recurrent or progressive BM. Any type of previous therapy was allowed, and disease was assessed by gadolinium (Gd)-enhanced magnetic resonance imaging (MRI). The primary end points were the evaluation of the dose-limiting toxicities (DLTs) and the determination of the maximum-tolerated dose (MTD). The secondary end points included objective response rate, clinical benefit and duration of response.

RESULTS

The lapatinib-temozolomide regimen showed a favorable toxicity profile because the MTD could not be reached. The most common adverse events (AEs) were fatigue, diarrhea and constipation. Disease stabilization was achieved in 10 out of 15 assessable patients. The estimated median survival time for the 16 patients with BM reached 10.94 months (95% CI: 1.09-20.79), whereas the median progression-free survival time was 2.60 months [95% confidence interval (CI): 1.82-3.37].

CONCLUSIONS

The lapatinib-temozolomide combination is well tolerated. Preliminary evidence of clinical activity was observed in a heavily pretreated population, as indicated by the volumetric reductions occurring in brain lesions.

Phase I study of oral CP-4126, a gemcitabine derivative, in patients with advanced solid tumors

CP-4126 is a gemcitabine (2',2'-difluorodeoxycytidine; dFdC) 5' elaidic acid ester. The purpose of this dose-escalating study was to assess safety, pharmacokinetics (PK) and preliminary antitumor activity of the oral formulation and to determine the recommended dose (RD) for phase II studies. The study had a two-step design: a non-randomized dose-escalating step I with oral CP-4126 alone, followed by a randomized, cross-over step II that compared oral CP-4126 with dFdC i.v.. CP-4126 was given on days 1,8,15 in a 4-week schedule with increasing doses until the RD was established. 26 patients with different solid tumours were enrolled in step I at seven dose levels (100-3,000 mg/day). The most frequent drug-related AEs were fatigue and dysgeusia, the majority being grade 1-2. One patient experienced a dose limiting toxicity after one dose of CP-4126 at 1,300 mg/day (ASAT grade 3). PK of CP-4126 could not be determined. The metabolites dFdC and dFdU obeyed dose-dependent pharmacokinetics. Exposures to dFdC were about ten-fold lower compared to exposures after comparable doses of dFdC i.v.. Nine patients reached stable disease as best response, whereby in one patient with vaginal carcinoma a 25 % reduction of tumor volume was reached. This study demonstrates that CP-4126 can be safely administered orally to patients up to 3,000 mg/day in a d1,8,15 q4w schedule with a tolerable safety profile. CP-4126 acts as a prodrug for dFdC when given orally, but because of the poor absorption and the rapid pre-systemic metabolism the study was terminated early and no RD could be determined.

OT3-01-07: The BEACON Study (BrEAst Cancer Outcomes with NKTR-102): A Phase 3 Open-Label, Randomized, Multicenter Study of NKTR-102 Versus Treatment of Physician's Choice (TPC) in Patients (pts) with Locally Recurrent or Metastatic Breast Cancer (MBC) Previously Treated with an Anthracycline, a Taxane, and Capecitabine (ATC)

Background

NKTR-102 is a next-generation topoisomerase I inhibitor-polymer conjugate with a markedly reduced Cmax and a continuous exposure profile compared to irinotecan. A phase 2 trial of single-agent NKTR-102 compared a dose of 145 mg/m2 every 2w or every 3w in 3rd-line MBC (Awada et al, ASCO 2011). Overall the ORR was 29% (including 3% CR) with the prior ATC subset demonstrating an ORR of 31%. Dosing every 3w was better tolerated; in this arm, median PFS equaled 5.3m and median OS equaled 13.1m.

Trial Design: NKTR-102 will be compared to TPC in an open-label, randomized, parallel, two arm multicenter Phase 3 pivotal study in pts with previously treated locally recurrent or metastatic breast cancer.

Key Entry Criteria: Adult females, with ECOG 0 or 1 with adequate liver, kidney and marrow function. All patients must have received prior therapy with an anthracycline (in neo/adjuvant or metastatic setting or both), a taxane (in neo/adjuvant or metastatic setting or both) and capecitabine (in neo/adjuvant or locally advanced/metastatic setting or both) unless not medically appropriate or explicitly contraindicated for the patient. All chemotherapy- and radiation-related toxicities must have resolved to ≤ Grade 1, except for stable sensory neuropathy ≤ Grade 2 and alopecia. Pts with brain metastases may be eligible, if stable for prior 4 weeks without steroids. Pts with Grade ≥ 2 pre-existing diarrhea or receiving chronic anti-diarrheal supportive care are not eligible.

Statistical Methods: The primary efficacy endpoint is OS. Secondary endpoints include ORR by RECIST v1.1 and PFS. Pts will be randomized 1:1 to NKTR-102 given IV at 145 mg/m2 over 90-min every 21 days or TPC. Patients randomized to TPC will receive single agent chemotherapy, limited to choice of one of the following 5 agents: eribulin, ixabepilone, vinorelbine, gemcitabine, or a taxane. The investigator must decide which agent will be given to the patient prior to randomization. Pts will be stratified by geographical region and disease characteristics.

Target Accrual: Approximately 840 patients (420 pts per treatment arm) will be randomized in order to obtain 615 deaths (alpha = 0.05; power 90% with one interim analysis scheduled when 50% of the deaths have occurred). PK sampling will be performed in a subset of pts and blood and/or tumor samples are planned for potential predictive markers of response and toxicity. Enrollment is expected to remain open until the end of 2013.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr OT3-01-07.

P1-17-10: Cabozantinib (XL184) in Patients with Metastatic Breast Cancer: Results from a Phase 2 Randomized Discontinuation Trial

Background: Cabozantinib is an oral, potent inhibitor of MET and VEGFR2. MET overexpression has been observed in metastatic breast cancer (MBC). High levels of VEGF and its receptors are associated with poor prognosis in patients (pts) with breast cancer. Simultaneous targeting of the MET and VEGF signaling pathways with cabozantinib may therefore be a promising treatment strategy. Results of a phase 2 randomized discontinuation trial (RDT) with single-agent cabozantinib have demonstrated clinical activity in a broad range of tumor types. In addition to observed effects on soft tissue lesions, cabozantinib has also been associated with effects on bone metastases as exhibited by partial or complete bone scan resolution, pain relief and/or reduction of narcotic use.

Methods: MBC pts (ER [+], triple [-] or inflammatory subtype) with progressive and measurable disease received single-agent cabozantinib at 100 mg qd PO over a 12 week (wk) lead-in period. Up to 4 prior treatment regimens (hormonal excluded) for MBC were allowed. Tumor response was assessed every 6 wks per mRECIST 1.0. Treatment beyond wk 12 was based on response: pts with partial response (PR) continued with open-label cabozantinib, those with stable disease (SD) were randomized to cabozantinib vs. placebo, and those with progressive disease were discontinued. The primary endpoint was objective response rate (ORR) in the lead-in period, and progression free survival in the randomized period. Post-hoc evaluations of bone scans were conducted.

Results: 20 MBC pts were enrolled with a median age of 55 years (range: 31–71).19 pts had invasive ductal carcinoma (1 pt with inflammatory MBC), and 1 pt had invasive lobular carcinoma. 75% of pts were ER/PR [+]; 15% were HER2/neu [+]. 85% of pts had visceral disease including 65% with liver metastases; 70% had bone disease. The median number of prior regimens was 3; 45% received prior anti-VEGF therapy. Most common related adverse events ≥ Grade 3 were fatigue/asthenia, 20%; and hand-foot syndrome, 20%. Dose reductions and permanent discontinuations for AEs occurred in 35% and 15% of pts, respectively.

Soft tissue effects: At wk 12, ORR per RECIST was 10% and overall disease control rate (PR+SD) was 45%. Notably, tumor shrinkage was observed in 15/16 pts (94%) with ≥1 post-baseline tumor assessment.

Bone effects: 2/3 pts evaluable by bone scan at baseline had partial resolution of lesions and one pt had SD on follow-up bone scans as early as Wk 6. Out of 7 pts receiving narcotics for bone pain, 3 pts reported improved pain and 2 pts had decreased narcotic use, per investigator. The majority of pts analyzed had declines in plasma CTx, an osteoclast marker. Additional enrollment and further bone marker analyses are ongoing.

Conclusions: Cabozantinib exhibits clinical activity in pts with MBC regardless of receptor and prior treatment status as reflected by high rate of tumor regression and effects on bone metastases. Cabozantinib is generally well tolerated and the safety profile is comparable to that seen with other tyrosine kinase inhibitors.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-17-10.

P3-16-08: A Phase 2, Randomized Open-Label Study of Iniparib, Administered Either Weekly or Twice-Weekly in Combination with Gemcitabine Plus Carboplatin in Patients with mTNBC

Background

Iniparib (BSI-201) is an investigational anticancer agent whose precise mechanism of action is under active investigation. In breast cancer cell lines and xenograft models of triple-negative breast cancer (TNBC), iniparib exhibits anti-proliferative activity and potentiates the cell cycle effects of some DNA damaging agents. In a randomized, open-label phase 2 study in pts with metastatic TNBC (mTNBC), iniparib combined with gemcitabine (G) and carboplatin (C) (GC) improved efficacy outcomes compared with GC alone. A confirmatory phase 3 study with GCI failed to meet pre-specified criteria for PFS and OS; however, an exploratory subset analysis demonstrated a potential benefit amongst 2nd/3rd line pts (O'Shaughnessy et al. ASCO 2011). Here we report results of a randomized phase 2 study (NCT01045304) in pts with mTNBC, which assesses efficacy and pharmacokinetics (PK) of iniparib administered either biw or qw in combination with GC.

Patients and methods: Eligible pts (N=163; median age 49 yrs) had documented and measurable TNBC, ECOG PS 0–1, normal organ/marrow function, and had received ≤2 prior chemotherapy (CT) regimens for metastatic disease. Pts were randomized (1:1) to receive G (1,000 mg/m2, IV, d 1, 8) plus C (AUC 2, IV, d 1, 8) and iniparib either biw (5.6 mg/kg, IV d 1,4,8,11) or qw (11.2 mg/kg, IV d 1,8) on a 21 d cycle. Pts were stratified according to prior CT for mTNBC (0 vs. 1–2). The primary efficacy endpoint was overall response rate (ORR; CR + PR); secondary endpoints included: clinical benefit rate (CBR; CR + PR + SD for 24 weeks), PFS, OS and PK.

Results: At the time of analysis, 23% of patients were still on treatment. The median number of cycles administered per patient was 6 in both arms; exposure to iniparib was identical. Safety data are not fully validated. All pts experienced at least 1 treatment emergent adverse event (TEAE). Grade (Gr) ≥3 TEAEs occurred in 94% and 85% of pts in the biw and qw arms, respectively. TEAEs Gr ≥3 occurring in ≥5% of pts regardless of relationship to study drug (biw vs qw) are as follows: blood and lymphatic 71% vs 67%; hepatobiliary 7.5% vs 9.8%; asthenia/fatigue 7.5% vs 11%; GI 8.8% vs 8.5%; infections 7.5% vs 3.7%; respiratory, thoracic and mediastinal 5% vs 8.5%, metabolism and nutrition 4% vs 6%. For response data see table.

Serial FDG-PET/CT for early outcome prediction in patients with metastatic colorectal cancer undergoing chemotherapy

BACKGROUND

The study purpose was to assess the predictive value of 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET)/computerized tomography (CT) metabolic response after a single course of chemotherapy in patients with metastatic colorectal cancer (mCRC).

PATIENTS AND METHODS

FDG-PET/CT scans were carried out at baseline and on day 14 in 41 patients with unresectable mCRC treated with a biweekly regimen of chemotherapy. Metabolic nonresponse was defined by <15% decrease in FDG uptake in the dominant proportion of the patient's lesions or if a lesion was found metabolically progressive. The PET-based response was correlated with radiological response (primary end point) and patient's outcome (secondary end points).

RESULTS

RECIST response rate in metabolically responding patients was 43% (10 of 23) compared with 0% (0 of 17) in nonresponding patients (P=0.002). The metabolic assessment's predictive performance for RECIST response was sensitivity 100% [95% confidence interval (CI) 69% to 100%], specificity 57% (95% CI 37% to 75%), positive predictive value 43% (95% CI 23% to 66%), and negative predictive value 100% (95% CI 80% to 100%). Comparing metabolically responding versus nonresponding patients, the hazard ratio (HR) was 0.28 (95% CI 0.10-0.76) for overall survival and 0.57 (95% CI 0.27-1.21) for progression-free survival.

CONCLUSION

The metabolic response measured by FDG-PET/CT after a single course of chemotherapy in mCRC is able to identify patients who will not benefit from the treatment.

Lapatinib ditosylate: expanding therapeutic options for receptor tyrosine-protein kinase erbB-2-positive breast cancer

Receptor tyrosine-protein kinase erbB-2 (HER2)-positive breast cancer is a specific entity with an aggressive behavior. Trastuzumab, a monoclonal antibody targeting erbB-2 (HER2) deeply transformed the outcome in patients. Nevertheless, resistance to trastuzumab is still a major concern. Lapatinib ditosylate is an orally available, small molecule targeting the tyrosine activity of the HER2 receptor. Lapatinib as a single agent and in combination therapy showed interesting activity in trastuzumab-resistant advanced tumors. In addition, lapatinib use seemed suitable in recurrent locally advanced inflammatory breast cancer and brain metastases. More recently, the Neo-ALTTO (NeoAdjuvant Lapatinib and/or Trastuzumab Treatment Optimisation) trial showed that lapatinib in combination with trastuzumab and paclitaxel significantly improved the pathological complete response in a neoadjuvant setting. Several clinical trials are still ongoing and data that may change current clinical practice are awaited with much interest.

TYRP1 mRNA expression in melanoma metastases correlates with clinical outcome

Background:

Clinical outcome of patients with high-risk melanoma cannot be reliably predicted on the basis of classical histopathological examination. Our study aimed to determine in melanoma metastases a gene expression profile associated with patient survival, and to identify and validate marker(s) of poor clinical outcome.

Methods:

Skin and lymph node metastases from melanoma patients (training population) were used to identify candidate prognostic marker(s) based on DNA microarray analysis. Additional skin metastases (validation population) were used to assess the prognostic value of the first ranked gene by real-time PCR.

Results:

We performed microarray analysis in the training population and generated a list of 278 probe sets associated with a shorter survival. We used the first ranked gene, tyrosinase-related protein 1 (TYRP1), further measured its expression in the validation population by real-time PCR and found it to be significantly correlated with distant metastasis-free survival (DMFS), overall survival (OS) and Breslow thickness. We also found that it was fairly well conserved in the course of the disease regardless of the delay to metastasis occurrence. Finally, although Tyrp1 protein (immunohistochemistry (IHC)) was only detected in about half of the samples, we showed that its expression also correlated with Breslow thickness.

Conclusion:

Our data indicate that TYRP1 mRNA expression level, at least in skin metastases, is a prognostic marker for melanoma, and is particularly useful when prognostic pathology parameters at the primary lesion are lacking. Its conserved expression further supports its use as a target for therapy.

Final results of NKTR-102, a topoisomerase I inhibitor-polymer conjugate, in patients (Pts) with pretreated metastatic breast cancer (MBC) demonstrating significant antitumor activity

269

Background: NKTR-102 is a topoisomerase I inhibitor-polymer conjugate with reduced peak concentration and a continuous concentration profile.

Methods: This was an open-label phase II study in MBC pts following PD on a taxane (T). Pts were randomized to NKTR-102 given IV at 145 mg/m2 over 90-min every 14 or 21 days. Efficacy endpoints included ORR by RECIST v1.0; PFS and OS.

Results: 70 pts (35 per schedule) randomized from Feb 2009 to May 2010 (median follow-up: 10 mo). Median age: 55 (range 33–83). ECOG PS 0/1: 40%/60%. Neoadjuvant and/or adjuvant: 74%. Median number of prior cytotoxic regimens for metastatic disease: 2. All pts had received prior T: 7% (adjuvant); 93% (metastatic). 89% had received prior anthracyclines (A): 63% (adjuvant); 26% (metastatic). 63% had received prior AT only (23% in MBC); an additional 26% had received prior AT/capecitabine (ATC). 61% were ER/PR+; 30% had TNBC; 86% had visceral metastases. Median PFS for q14d, q21d and overall were 3.5 mo, 5.3 mo and 4.6 mo. Median OS for q14d, q21d and overall were 8.8 mo, 13.1 mo and 10.3 mo. Toxicity was manageable, with diarrhea as the most common grade 3+ toxicity, with median time to onset ∼3 mo. Discontinuation from study drug due to AEs: 20%/14% for q14d/q21d. Neuropathy was absent; alopecia was minimal (20%/11% grade 1–2 for q14d/q21d).

Conclusions: NKTR-102 demonstrates significant anti-tumor activity in pts with advanced MBC, including poor prognosis pts with TNBC and having received prior ATC. A phase III study is being planned in patients with MBC previously treated with taxanes.

[Table: see text]

Maximising the duration of disease control in metastatic renal cell carcinoma with targeted agents: an expert agreement

With six targeted agents approved (sorafenib, sunitinib, temsirolimus, bevacizumab [+interferon], everolimus and pazopanib), many patients with metastatic renal cell carcinoma (mRCC) will receive multiple therapies. However, the optimum sequencing approach has not been defined. A group of European experts reviewed available data and shared their clinical experience to compile an expert agreement on the sequential use of targeted agents in mRCC. To date, there are few prospective studies of sequential therapy. The mammalian target of rapamycin (mTOR) inhibitor everolimus was approved for use in patients who failed treatment with inhibitors of vascular endothelial growth factor (VEGF) and VEGF receptors (VEGFR) based on the results from a Phase III placebo-controlled study; however, until then, the only licensed agents across the spectrum of mRCC were VEGF(R) inhibitors (sorafenib, sunitinib and bevacizumab + interferon), and as such, a large body of evidence has accumulated regarding their use in sequence. Data show that sequential use of VEGF(R) inhibitors may be an effective treatment strategy to achieve prolonged clinical benefit. The optimal place of each targeted agent in the treatment sequence is still unclear, and data from large prospective studies are needed. The Phase III AXIS study of second-line sorafenib vs. axitinib (including post-VEGF(R) inhibitors) has completed, but the data are not yet published; other ongoing studies include the Phase III SWITCH study of sorafenib-sunitinib vs. sunitinib-sorafenib (NCT00732914); the Phase III 404 study of temsirolimus vs. sorafenib post-sunitinib (NCT00474786) and the Phase II RECORD 3 study of sunitinib-everolimus vs. everolimus-sunitinib (NCT00903175). Until additional data are available, consideration of patient response and tolerability to treatment may facilitate current decision-making regarding when to switch and which treatment to switch to in real-life clinical practice.