Adjuvant T-DM1 versus trastuzumab in patients with residual invasive disease after neoadjuvant therapy for HER2-positive breast cancer: subgroup analyses from KATHERINE

BACKGROUND

In the KATHERINE study (NCT01772472), patients with residual invasive early breast cancer (EBC) after neoadjuvant chemotherapy (NACT) plus human epidermal growth factor receptor 2 (HER2)-targeted therapy had a 50% reduction in risk of recurrence or death with adjuvant trastuzumab emtansine (T-DM1) versus trastuzumab. Here, we present additional exploratory safety and efficacy analyses.

PATIENTS AND METHODS

KATHERINE enrolled HER2-positive EBC patients with residual invasive disease in the breast/axilla at surgery after NACT containing a taxane (± anthracycline, ± platinum) and trastuzumab (± pertuzumab). Patients were randomized to adjuvant T-DM1 (n = 743) or trastuzumab (n = 743) for 14 cycles. The primary endpoint was invasive disease-free survival (IDFS).

RESULTS

The incidence of peripheral neuropathy (PN) was similar regardless of neoadjuvant taxane type. Irrespective of treatment arm, baseline PN was associated with longer PN duration (median, 105-109 days longer) and lower resolution rate (∼65% versus ∼82%). Prior platinum therapy was associated with more grade 3-4 thrombocytopenia in the T-DM1 arm (13.5% versus 3.8%), but there was no grade ≥3 hemorrhage in these patients. Risk of recurrence or death was decreased with T-DM1 versus trastuzumab in patients who received anthracycline-based NACT [hazard ratio (HR) = 0.51; 95% confidence interval (CI): 0.38-0.67], non-anthracycline-based NACT (HR = 0.43; 95% CI: 0.22-0.82), presented with cT1, cN0 tumors (0 versus 6 IDFS events), or had particularly high-risk tumors (HRs ranged from 0.43 to 0.72). The central nervous system (CNS) was more often the site of first recurrence in the T-DM1 arm (5.9% versus 4.3%), but T-DM1 was not associated with a difference in overall risk of CNS recurrence.

CONCLUSIONS

T-DM1 provides clinical benefit across patient subgroups, including small tumors and particularly high-risk tumors and does not increase the overall risk of CNS recurrence. NACT type had a minimal impact on safety.

Exposure-response relationship of ramucirumab in patients with advanced second-line colorectal cancer: exploratory analysis of the RAISE trial

PURPOSE

To characterize ramucirumab exposure-response relationships for efficacy and safety in patients with metastatic colorectal cancer (mCRC) using data from the RAISE study.

METHODS

Sparse pharmacokinetic samples were collected; a population pharmacokinetic analysis was conducted. Univariate and multivariate Cox proportional hazards models analyzed the relationship between predicted ramucirumab minimum trough concentration at steady state (C min,ss) and survival. Kaplan-Meier analysis was used to evaluate survival from patients in the ramucirumab plus folinic acid, 5-fluorouracil, and irinotecan (FOLFIRI) treatment arm stratified by C min,ss quartiles (Q). An ordered categorical model analyzed the relationship between C min,ss and safety outcomes.

RESULTS

Pharmacokinetic samples from 906 patients were included in exposure-efficacy analyses; samples from 905 patients were included in exposure-safety analyses. A significant association was identified between C min,ss and overall survival (OS) and progression-free survival (PFS) (p < 0.0001 for both). This association remained significant after adjusting for baseline factors associated with OS or PFS (p < 0.0001 for both). Median OS was 11.5, 12.9, 16.4, and 16.7, and 12.4 months for ramucirumab C min,ss Q1, Q2, Q3, Q4, and placebo group, respectively. Median PFS was 5.4, 4.6, 6.8, 8.5, and 5.2 months for ramucirumab C min,ss Q1, Q2, Q3, Q4, and placebo group, respectively. The risk of Grade ≥3 neutropenia was associated with an increase in ramucirumab exposure.

CONCLUSIONS

Exploratory exposure-response analyses suggested a positive relationship between efficacy and ramucirumab exposure with manageable toxicities in patients from the RAISE study with mCRC over the ranges of exposures achieved by a dose of 8 mg/kg every 2 weeks in combination with FOLFIRI.

Long-term survival and biomarker correlates of tasquinimod efficacy in a multicenter randomized study of men with minimally symptomatic metastatic castration-resistant prostate cancer

PURPOSE

Tasquinimod (Active Biotech) is an oral immunomodulatory, anti-angiogenic, and anti-metastatic agent that delayed metastatic disease progression in a randomized placebo-controlled phase II trial in men with metastatic castration-resistant prostate cancer (mCRPC). Here, we report long-term survival with biomarker correlates from this trial.

EXPERIMENTAL DESIGN

Two hundred and one (134 tasquinimod and 67 placebo) men with mCRPC were evaluated. Forty-one men randomized to placebo crossed over to tasquinimod. Survival data were collected with a median follow-up time of 37 months. Exploratory biomarker studies at baseline and over time were collected to evaluate potential mechanism-based correlates with tasquinimod efficacy including progression-free survival (PFS) and overall survival (OS).

RESULTS

With 111 mortality events, median OS was 33.4 months for tasquinimod versus 30.4 months for placebo overall, and 34.2 versus 27.1 months in men with bone metastases (n = 136), respectively. Multivariable analysis demonstrated an adjusted HR of 0.52 [95% confidence interval (CI), 0.35-0.78; P = 0.001] for PFS and 0.64 (95% CI, 0.42-0.97; P = 0.034) for OS, favoring tasquinimod. Time-to-symptomatic progression was improved with tasquinimod (P = 0.039, HR = 0.42). Toxicities tended to be mild in nature and improved over time. Biomarker analyses suggested a favorable impact on bone alkaline phosphatase and lactate dehydrogenase (LDH) over time and a transient induction of inflammatory biomarkers, VEGF-A, and thrombospondin-1 levels with tasquinimod. Baseline levels of thrombospondin-1 less than the median were predictive of treatment benefit.

CONCLUSIONS

The survival observed in this trial of men with minimally symptomatic mCRPC suggests that the prolongation in PFS with tasquinimod may lead to a survival advantage in this setting, particularly among men with skeletal metastases, and has a favorable risk:benefit ratio.

Long-term follow-up of lenalidomide in relapsed/refractory mantle cell lymphoma: subset analysis of the NHL-003 study

BACKGROUND

Mantle cell lymphoma (MCL) is an uncommon type of non-Hodgkin lymphoma with poor overall prognosis, requiring the development of new therapies. Lenalidomide is an immunomodulatory agent demonstrating antitumor and antiproliferative effects in MCL. We report results from a long-term subset analysis of 57 patients with relapsed/refractory MCL from the NHL-003 phase II multicenter study of single-agent lenalidomide in patients with aggressive lymphoma

DESIGN

Lenalidomide was administered orally 25 mg daily on days 1-21 every 28 days until progressive disease (PD) or intolerability. The primary end point was overall response rate (ORR).

RESULTS

Fifty-seven patients with relapsed/refractory, advanced-stage MCL had a median of three prior therapies. The ORR was 35% [complete response (CR)/CR unconfirmed (CRu) 12%], with a median duration of response (DOR) of 16.3 months (not yet reached in patients with CR/CRu) by blinded independent central review. The median time to first response was 1.9 months. Median progression-free survival was 8.8 months, and overall survival had not yet been reached. The most common grade 3/4 adverse events (AEs) were neutropenia (46%), thrombocytopenia (30%), and anemia (13%).

CONCLUSIONS

These results show the activity of lenalidomide in heavily pretreated, relapsed/refractory MCL. Responders had a durable response with manageable side-effects. Clinical trial number posted on www.clinicaltrials.gov NCT00413036.

OT1-02-05: A Phase III Clinical Trial Comparing Trastuzumab Given Concurrently with Radiation Therapy to Radiation Therapy (RT) Alone for Women with HER2−Positive DCIS Resected by Lumpectomy: NSABP B-43

Background

Because a substantial portion of DCIS is ER negative and overexpresses HER2, therapy targeting this protein is a promising strategy for HER2−overexpressing DCIS.

Preclinical studies have shown that trastuzumab (T) boosts the effectiveness of RT in xenograft models and in cell lines with no detrimental effect on irradiated HER2−normal cells. Studies correlating clinical response with molecular markers in T-treated patients show that apoptosis occurs within 1 wk of starting singleagent T, with little effect on proliferation. Shorter duration treatments with this agent require investigation. Adjuvant trials using T during breast irradiation have already provided ample safety evidence. Will T administered during WBI improve lumpectomy + WBI results in women with HER2−positive DCIS? This trial will allow us to better understand the biology of breast cancer and its prevention and will extend the benefits of breast-conserving surgery for women with DCIS.

Trial Design: Post lumpectomy for DCIS without evidence of an invasive component, a central review of each patient's pure DCIS lesion is carried out for HER2 by IHC analysis. If the HER2 is 2+, FISH analysis is done, and patients whose tumors are HER2 3+ or FISH positive can be randomly assigned to receive 2 doses of T 3 wk apart during WBI or to receive WBI alone.

Eligibility criteria: Women 18 years or older with an ECOG status of 0 or 1 who have undergone a margin-clear lumpectomy for DCIS and whose tumors are clinically or pathologically node negative are eligible. DCIS must be HER2 positive by central testing. ER and/or PR status must be known before random assignment.

Specific aims: The primary aim is to determine if T given concurrently with WBI is more beneficial in preventing IBC recurrence, ipsilateral skin cancer recurrence, or ipsilateral DCIS compared with WBI alone for HER2−positive DCIS resected by lumpectomy. Secondary aims are to compare the possible benefit of T given during WBI to that of WBI alone in preventing regional or distant recurrence and contralateral invasive or DCIS breast cancer. B-43 will determine if invasive or DCIS DFS, recurrence-free interval, and OS can be improved with the addition of T to WBI. The effects of T on ovarian function in premenopausal women will also be assessed.

Statistical methods and accrual: Our design calls for accrual of 2000 patients during a 7.9-year period. As of May 31, 2011, 578 patients have been entered. A definitive analysis of primary endpoints will be performed when 163 ipsilateral breast cancer events occur (7.5 and 8 years after protocol initiation). This number of events affords 80% power to detect a hazard reduction of 36%, from 1.73 ipsilateral breast cancer events per 100 patient-years to 1.11 events per 100 patient-years. The 36% observed reduction in the hazard of IIBCR-SCR-DCIS on the T arm is based on a projection of 40% hazard reduction if the compliance were perfect, with a 10% noncompliance rate.

Supported by PHS grants NCI-U10-CA-69651, NCI-U10-CA-12027, and NCI P30-CA-14599 from the US NCI and Genentech, Inc.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr OT1-02-05.

Efficacy and safety of lenalidomide oral monotherapy in patients with relapsed or refractory diffuse large B-cell lymphoma: Results from an international study (NHL-003)

e19504

Background: Patients with diffuse large-B-cell lymphoma (DLBCL) who are not cured with R-CHOP or high-dose chemotherapy with autologous stem cell rescue have a dismal prognosis. A recent phase II trial (NHL-002) of lenalidomide in patients with relapsed or refractory aggressive non-Hodgkin's lymphoma (NHL) demonstrated a 19% overall response rate (ORR) with a 7-month median duration of response (DR) in the subset of patients with DLBCL. A supporting international phase II trial (NHL-003) of single-agent lenalidomide was initiated for patients with relapsed or refractory aggressive NHL that had received at least one prior treatment and had measurable disease. Herein, we report the data from the DLBCL patients enrolled in this trial. Methods: Patients received 25 mg oral lenalidomide once daily on days 1–21 of every 28-day cycle and continued therapy until disease progression or toxicity. The 1999 IWLRC methodology was used to assess response and progression. Results: One hundred-three DLBCL patients were enrolled and were evaluable for response assessment. The median age was 66 years (21–87) and 70 patients (68%) were male. Median time from diagnosis was 2 years (0.4–18.6), patients had received a median of 3 prior treatment regimens (1–10) and 46 of the patients (45%) had received a prior stem cell transplant (DLBCL-stem cell). Response rates are shown in the Table . Grade 3 or 4 adverse events occurring in more than 5% of patients were neutropenia (34%), thrombocytopenia (18%), asthenia (9%), anemia (8%), leucopenia (7%), back pain (6%) and dyspnea (6%). Conclusions: This international study demonstrates that lenalidomide is active in heavily pre-treated patients with relapsed or refractory DLBCL and has manageable side effects.

[Table: see text]

[Table: see text]

Phase II trial of bevacizumab in combination with temozolomide and regional radiation therapy for up-front treatment of patients with newly diagnosed glioblastoma multiforme

2000

Background: Bevacizumab (BV) is a humanized monoclonal antibody directed against the vascular endothelial growth factor (VEGF). Based on the promising activity of BV in the treatment of recurrent glioblastoma, we are conducting a phase II trial to determine whether up-front treatment of newly diagnosed GBM with BV may be more advantageous than withholding BV until recurrence. In this trial, we evaluate the safety and efficacy of BV combined with standard of care radiation (RT) and temozolomide (TMZ) and radiation (RT) for newly-diagnosed GBM. Methods: This is a phase II trial with a 10-patient pilot and 60-patient expansion phases. Newly-diagnosed GBM patients with no prior treatments are eligible. Primary outcome measure is overall survival; the secondary outcome measure is TTP and 12-month survival. Therapy began between 3–5 weeks of surgery with BV (10 mg/kg every 2 weeks), TMZ (75 mg/m2 daily), and external beam RT (30 x 200 Gy) on the same day. After completion of radiation, patients are then placed on a maintenance phase of BV (10mg/kg every 2 weeks) and TMZ (150–200 mg/m2 5 out of every 28 days) until progression or 24 months in which patients are then maintained on BV only. Results: 70 of 70 projected GBM patients have been enrolled between August 2006 and November 2008 at UCLA and Kaiser Permanente (KP) (Northern and Southern California). All patients had resections to ensure that frozen tissue (>200mg) was collected. The median age was 57.4 years (range 31–75). MGMT methylation analysis has been performed on 52/70 patients with ∼40% showing methylation. Severe adverse events to date have included ischemic stroke, pulmonary embolus, wound breakdown, GI bleeding/perforation, and renal dysfunction. Isolated cases of retinal detachment and optic neuropathy have also been observed. As of now, 35/70 patients are off study (26 due to progression and 9 due to SAE). Preliminary TTP by Kaplan-Meier analysis is promising compared to that of a UCLA/KP control group of patients that received the conventional RT/TMZ regimen. Conclusions: Addition of BV to the standard regimen of TMZ and RT for newly-diagnosed GBM is well-tolerated and shows promising efficacy. More detailed analysis of safety and efficacy will presented.

[Table: see text]

Efficacy and safety of lenalidomide oral monotherapy in patients with relapsed or refractory mantle-cell lymphoma: Results from an international study (NHL-003)

8569

Introduction: Relapsed or refractory MCL patients demonstrated a promising overall response rate (ORR) of 53% with a median duration of response (DR) of 13.7 months to single-agent lenalidomide when analyzed as a subset in a recent a phase II study (NHL-002). A supporting international phase II trial (NHL-003) of single-agent lenalidomide was initiated for patients with relapsed or refractory aggressive NHL. In this report, we analyze the current results from the MCL patients enrolled in this trial. Methods: Patients with relapsed or refractory MCL and measurable disease 2 cm after at least 1 prior treatment regimen were eligible. Patients received 25 mg of lenalidomide orally once daily on days 1–21 of every 28-day cycle. Patients continued therapy until disease progression or toxicity. The 1999 IWLRC methodology was used to assess response and progression. Results: Fifty-four MCL patients were enrolled and were evaluable for response assessment. Median age was 69 years (33–82) and 40 patients (74%) were male. Median time from diagnosis was 3.2 years (0.4–10.4), patients had received a median of 3 prior treatments (1–8), 17 of the patients (32%) had received prior bortezomib therapy (MCL-bortezomib), and 14 (26%) had received a prior stem cell transplant (MCL-stem cell). Response rates are shown in the Table. The most common grade 3 or 4 adverse events were neutropenia (43%), thrombocytopenia (22%) and anemia (11%). Conclusions: This is the second study to demonstrate that lenalidomide oral monotherapy is effective in the treatment of patients with relapsed or refractory MCL, with manageable side effects.

[Table: see text]

[Table: see text]

Biological effects in vitro of monoclonal antibodies to human epidermal growth factor receptors

Four mouse hybridomas secreting monoclonal immunoglobulin G (IgG) antibodies to epidermal growth factor (EGF) receptors of A431 cells were obtained independently from four fusion experiments. Three of the antibodies, 528 IgG, 225 IgG, and 579 IgG, inhibited the binding of [125I]EGF to A431 cells by at least 95%, and they competed with each other for binding to A431 cells. These antibodies bound to A431 cells, HeLa-S cells and human foreskin fibroblasts with dissociation constants in the range of Kd = 0.6 X 10(-9) to 2.5 X 10(-9) M. The fourth monoclonal antibody, 455 IgG, bound to A431 cells with lower affinity (Kd = 2.0 X 10(-8) M), and it had no effect on the binding of either EGF or the other antibodies to A431 cells. All four antibodies immunoprecipitated EGF receptors from Triton X-100 extracts of A431 membranes, but they were unable to bind to three rodent cell lines. In biological assays, none of the antibodies was able to mimic EGF. The antibodies which inhibited the binding of EGF blocked EGF-enhanced phosphorylation of A431 membrane proteins and inhibited EGF induced human fibroblast proliferation. These three antagonistic antibodies also partially reversed the inhibition of A431 growth by EGF. In contrast, 455 IgG had no effect on the early or delayed cellular responses to EGF.

Growth stimulation of A431 cells by epidermal growth factor: identification of high-affinity receptors for epidermal growth factor by an anti-receptor monoclonal antibody

Epidermal growth factor (EGF) at 3 nM maximally inhibits the proliferation of A431 epidermoid carcinoma cells. We show that at lower concentrations, in the range of 3-100 pM, EGF has a mitogenic effect on A431 cells. In the presence of 100 nM anti-EGF-receptor monoclonal IgG (designated 528), which inhibits A431 cell proliferation and blocks greater than 95% of EGF binding, EGF becomes mitogenic for A431 cells at concentrations up to 3 nM. These results suggest that a minor population of high-affinity EGF receptors may be involved in stimulation of A431 cell proliferation. Saturation binding assays with 125I-labeled EGF indicate that approximately equal to 0.1-0.2% of receptors for EGF are high-affinity receptors that bind EGF with an estimated Kd of 7 X 10(-11) M. This affinity is nearly 2 orders of magnitude higher than that of the remaining EGF receptors. Although A431 cell proliferation is maximally inhibited by nonsaturating amounts of EGF (3 nM), maximal inhibition by 528 IgG (approximately equal to 70% of maximal inhibition by EGF) requires saturating concentrations of antibody (approximately equal to 15 nM). Unlike EGF, rapid down-regulation is not observed with 528 IgG. These results indicate different mechanisms of growth inhibition of A431 cells by EGF and 528 IgG.