Elizabeth Crowley

A phase I study of the safety and pharmacokinetics of the histone deacetylase inhibitor belinostat administered in combination with carboplatin and/or paclitaxel in patients with solid tumours

Background:This phase I study assessed the maximum tolerated dose, dose-limiting toxicity (DLT) and pharmacokinetics of belinostat with carboplatin and paclitaxel and the anti-tumour activity of the combination in solid tumours.Methods:Cohorts of three to six patients were treated with escalating doses of belinostat administered intravenously once daily, days 1–5 q21 days; on day 3, carboplatin (area under the curve (AUC) 5) and/or paclitaxel (175 mg m−2) were administered 2–3 h after the end of the belinostat infusion.Results:In all 23 patients received 600–1000 mg m−2 per day of belinostat with carboplatin and/or paclitaxel. No DLT was observed. The maximal administered dose of belinostat was 1000 mg m−2 per day for days 1–5, with paclitaxel (175 mg m−2) and carboplatin AUC 5 administered on day 3. Grade III/IV adverse events were (n; %): leucopenia (5; 22%), neutropenia (7; 30%), thrombocytopenia (3; 13%) anaemia (1; 4%), peripheral sensory neuropathy (2; 9%), fatigue (1; 4%), vomiting (1; 4%) and myalgia (1; 4%). The pharmacokinetics of belinostat, paclitaxel and carboplatin were unaltered by the concurrent administration. There were two partial responses (one rectal cancer and one pancreatic cancer). A third patient (mixed mullerian tumour of ovarian origin) showed a complete CA-125 response. In addition, six patients showed a stable disease lasting ⩾6 months.Conclusion:The combination was well tolerated, with no evidence of pharmacokinetic interaction. Further evaluation of anti-tumour activity is warranted.

EMERGE: A Randomized Phase II Study of the Antibody-Drug Conjugate Glembatumumab Vedotin in Advanced Glycoprotein NMB–Expressing Breast Cancer

PURPOSE Glycoprotein NMB (gpNMB), a negative prognostic marker, is overexpressed in multiple tumor types. Glembatumumab vedotin is a gpNMB-specific monoclonal antibody conjugated to the potent cytotoxin monomethyl auristatin E. This phase II study investigated the activity of glembatumumab vedotin in advanced breast cancer by gpNMB expression. PATIENTS AND METHODS Patients (n = 124) with refractory breast cancer that expressed gpNMB in ≥ 5% of epithelial or stromal cells by central immunohistochemistry were stratified by gpNMB expression (tumor, low stromal intensity, high stromal intensity) and were randomly assigned 2:1 to glembatumumab vedotin (n = 83) or investigators choice (IC) chemotherapy (n = 41). The study was powered to detect overall objective response rate (ORR) in the glembatumumab vedotin arm between 10% (null) and 22.5% (alternative hypothesis) with preplanned investigation of activity by gpNMB distribution and/or intensity (Stratum 1 to Stratum 3). RESULTS Glembatumumab vedotin was well tolerated as compared with IC chemotherapy (less hematologic toxicity; more rash, pruritus, neuropathy, and alopecia). ORR was 6% (five of 83) for glembatumumab vedotin versus 7% (three of 41) for IC, without significant intertreatment differences for predefined strata. Secondary end point revealed ORR of 12% (10 of 83) versus 12% (five of 41) overall, and 30% (seven of 23) versus 9% (one of 11) for gpNMB overexpression (≥ 25% of tumor cells). Unplanned analysis showed ORR of 18% (five of 28) versus 0% (0 of 11) in patients with triple-negative breast cancer (TNBC), and 40% (four of 10) versus 0% (zero of six) in gpNMB-overexpressing TNBC. CONCLUSION Glembatumumab vedotin is well tolerated in heavily pretreated patients with breast cancer. Although the primary end point in advanced gpNMB-expressing breast cancer was not met for all enrolled patients (median tumor gpNMB expression, 5%), activity may be enhanced in patients with gpNMB-overexpressing tumors and/or TNBC. A pivotal phase II trial (METRIC [Metastatic Triple-Negative Breast Cancer]) is underway.

Phase I/II Study of the Antibody-Drug Conjugate Glembatumumab Vedotin in Patients With Locally Advanced or Metastatic Breast Cancer

PURPOSE Glycoprotein NMB (gpNMB), a novel transmembrane protein overexpressed in 40% to 60% of breast cancers, promotes metastases in animal models and is a prognostic marker of a poor outcome in patients. The antibody-drug conjugate glembatumumab vedotin consists of a fully human anti-gpNMB monoclonal antibody, conjugated via a cleavable linker to monomethyl auristatin E. Glembatumumab vedotin is generally well tolerated, with observed objective responses in advanced melanoma. This is, to our knowledge, the first study of glembatumumab vedotin in breast cancer. PATIENTS AND METHODS Eligible patients had advanced/metastatic breast cancer with at least two prior chemotherapy regimens, including taxane, anthracycline, and capecitabine. A standard 3+3 dose escalation was followed by a phase II expansion. Immunohistochemistry for gpNMB was performed retrospectively for patients with available tumor tissue. RESULTS Forty-two patients were enrolled. Dose-limiting toxicity (DLT) consisted of worsening neuropathy at 1.34 mg/kg. After excluding patients with baseline neuropathy more than grade 1, no DLT occurred through 1.88 mg/kg (the phase II dose). The phase II primary activity end point was met (12-week progression-free survival [PFS12] = 9 of 27 patients; 33%). Sixteen of 19 (84%) patients tested had gpNMB-positive tumors. At the phase II dose, median PFS was 9.1 weeks for all patients, 17.9 weeks for patients with triple-negative breast cancer (TNBC), and 18.0 weeks for patients with gpNMB-positive tumors. Two patients had confirmed partial responses; both had gpNMB-positive tumors and one had TNBC. CONCLUSION Glembatumumab vedotin has an acceptable safety profile. Preliminary evidence of activity in treatment-resistant metastatic breast cancer requires confirmation, such as the phase II randomized trial (EMERGE) that also examines the relationship between activity and gpNMB distribution/intensity.

Phase II activity of belinostat (PXD-101), carboplatin, and paclitaxel in women with previously treated ovarian cancer.

Background Preclinical data show that belinostat (Bel) is synergistic with carboplatin and paclitaxel in ovarian cancer. To further evaluate the clinical activity of belinostat, carboplatin, and paclitaxel (BelCaP), a phase 1b/2 study was performed, with an exploratory phase 2 expansion planned specifically for women with recurrent epithelial ovarian cancer (EOC). Methods Thirty-five women were treated on the phase 2 expansion cohort. BelCap was given as follows: belinostat, 1000 mg/m2 daily for 5 days with carboplatin, AUC 5; and paclitaxel, 175 mg/m2 given on day 3 of a 21-day cycle. The primary end point was overall response rate (ORR), using a Simon 2 stage design. Results The median age was 60 years (range, 39–80 years), and patients had received a median of 3 prior regimens (range, 1–4). Fifty-four percent had received more than two prior platinum-based combinations, sixteen patients (46%) had primary platinum-resistant disease, whereas 19 patients (54%) recurred within 6 months of their most recent platinum treatment. The median number of cycles of BelCaP administered was 6 (range, 1–23). Three patients had a complete response, and 12 had a partial response, for an ORR of 43% (95% confidence interval, 26%–61%). When stratified by primary platinum status, the ORR was 44% among resistant patients and 63% among sensitive patients. The most common drug-related adverse events related to BelCaP were nausea (83%), fatigue (74%), vomiting (63%), alopecia (57%), and diarrhea (37%). With a median follow-up of 4 months (range, 0–23.3 months), 6-month progression-free survival is 48% (95% confidence interval, 31%–66%). Median overall survival was not reached during study follow-up. Conclusions Belinostat, carboplatin, and paclitaxel combined was reasonably well tolerated and demonstrated clinical benefit in heavily-pretreated patients with EOC. The addition of belinostat to this platinum-based regimen represents a novel approach to EOC therapy and warrants further exploration.

Phase I/II Study of the Antibody-Drug Conjugate Glembatumumab Vedotin in Patients With Advanced Melanoma

PURPOSE The antibody-drug conjugate glembatumumab vedotin links a fully human immunoglobulin G2 monoclonal antibody against the melanoma-related glycoprotein NMB (gpNMB) to the potent cytotoxin monomethyl auristatin E. This study evaluated the safety and activity of glembatumumab vedotin in patients with advanced melanoma. PATIENTS AND METHODS Patients received glembatumumab vedotin every 3 weeks (schedule 1) in a dose escalation and phase II expansion at the maximum-tolerated dose (MTD). Dosing during 2 of 3 weeks (schedule 2) and weekly (schedule 3) was also assessed. The primary end points were safety and pharmacokinetics. The secondary end points included antitumor activity, gpNMB expression, and immunogenicity. RESULTS One hundred seventeen patients were treated using schedule 1 (n = 79), schedule 2 (n = 15), or schedule 3 (n = 23). The MTDs were 1.88, 1.5, and 1.0 mg/kg for schedules 1, 2, and 3, respectively. Grade 3/4 treatment-related toxicities that occurred in two or more patients included rash, neutropenia, fatigue, neuropathy, arthralgia, myalgia, and diarrhea. Three treatment-related deaths (resulting from pneumococcal sepsis, toxic epidermal necrolysis, and renal failure) occurred at doses exceeding the MTDs. In the schedule 1 phase II expansion cohort (n = 34), five patients (15%) had a partial response and eight patients (24%) had stable disease for ≥ 6 months. The objective response rate (ORR) was 2 of 6 (33%) for the schedule 2 MTD and 3 of 12 (25%) for the schedule 3 MTD. Rash was correlated with a greater ORR and improved progression-free survival. CONCLUSION Glembatumumab vedotin is active in advanced melanoma. The schedule 1 MTD (1.88 mg/kg once every 3 weeks) was associated with a promising ORR and was generally well tolerated. More frequent dosing was potentially associated with a greater ORR but increased toxicity.

A Phase (Ph) I/II Study of CR011-VcMMAE, an Antibody-Drug Conjugate, in Patients (Pts) with Locally Advanced or Metastatic Breast Cancer (MBC).

Background: Glycoprotein NMB (GPNMB), also known as osteoactivin, is expressed in 25-40% of breast cancers and is associated with an increased risk of recurrence. This is the first study of CR011-vcMMAE, a fully-human monoclonal anti-GPNMB antibody conjugated to the tubulin inhibitor monomethylauristatin E (MMAE), in pts with breast cancer.Methods: Eligible pts with MBC had ³ 2 prior chemotherapy regimens, including a taxane, an anthracycline, and capecitabine; and ECOG PS ≤ 2. Doses were escalated to 1.88 mg/kg IV q3w (the maximum tolerated dose [MTD] in a previous study of patients with melanoma) using a standard 3+3 design followed by a Ph II expansion at the MTD. Pts received CR011-vcMMAE until disease progression (PD) or intolerable toxicity. The primary endpoint of the Ph II study was 12-week progression free rate, defined as the proportion of patients who were alive and free of progressive disease 12 weeks from the first dose of CR011-vcMMAE. A Simon two-stage minimax design was used (p0=0.1; p1=0.3, α=β=0.1) with 16 patients in the first stage and a total of 25 pts. Secondary endpoints included objective response rate and duration of response. IHC with a goat polyclonal antibody to GPNMB was performed on pt biopsy specimens.Results: In Ph I, 14 pts were treated with CR011-vcMMAE at 1.0 mg/kg (n=3), 1.34 mg/kg (n=5), and 1.88 mg/kg (n=6). In the first 2 pts at 1.34 mg/kg, dose limiting toxicity of worsening peripheral sensory neuropathy was observed. Pts with baseline neuropathy worse than grade 1 were subsequently excluded. There were 3 partial responses, one confirmed, and 1.88 mg/kg q3w was selected for Ph II. In Ph II, 14 pts with MBC (median age 57 years, range 34 - 76) had a median of 5 prior regimens; median follow up was 6 weeks; 12 pts are ongoing (median duration 6 weeks, range 1 - 14 weeks). Two pts were progression-free at 12 weeks, therefore the study has met the criteria for advancement to the second stage. The most common AEs were rash (61%), fatigue (50%) and alopecia (50%). The most common grade 3/4 AEs were neutropenia (17%) and neuropathy (11%). IHC staining of 5 patient biopsies revealed 2 with positive GPNMB expression, including one of the patients with PR.Conclusions: CR011-vcMMAE is active and well-tolerated in heavily pretreated pts with advanced breast cancer. The Phase II study has met the criteria for advancement into the second stage, and enrollment is ongoing. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6096.

Modeling intracranial second tumor risk and estimates of clinical toxicity with various radiation therapy techniques for patients with pituitary adenoma.

This study was designed to estimate the risk of radiation-associated tumors and clinical toxicity in the brain following fractionated radiation treatment of pituitary adenoma. A standard case of a patient with a pituitary adenoma was planned using 8 different dosimetric techniques. Total dose was 50.4 Gy (GyE) at daily fractionation of 1.8 Gy (GyE). All methods utilized the same CT simulation scan with designated target and normal tissue volumes. The excess risk of radiation-associated second tumors in the brain was calculated using the corresponding dose-volume histograms for the whole brain and based on the data published by the United Nation Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) and a risk model proposed by Schneider. The excess number of second tumor cases per 10,000 patients per year following radiation is 9.8 for 2-field photons, 18.4 with 3-field photons, 20.4 with photon intensity modulated radiation therapy (IMRT), and 25 with photon stereotactic radiotherapy (SRT). Proton radiation resulted in the following excess second tumor risks: 2-field = 5.1, 3-field = 12, 4-field = 15, 5-field = 16. Temporal lobe toxicity was highest for the 2-field photon plan. Proton radiation therapy achieves the best therapeutic ratio when evaluating plans for the treatment of pituitary adenoma. Temporal lobe toxicity can be reduced through the use of multiple fields but is achieved at the expense of exposing a larger volume of normal brain to radiation. Limiting the irradiated volume of normal brain by reducing the number of treatment fields is desirable to minimize excess risk of radiation-associated second tumors.

Dose--volume effects on patient-reported acute gastrointestinal symptoms during chemoradiation therapy for rectal cancer.

PURPOSE Research on patient-reported outcomes (PROs) in rectal cancer is limited. We examined whether dose-volume parameters of the small bowel and large bowel were associated with patient-reported gastrointestinal (GI) symptoms during 5-fluorouracil (5-FU)-based chemoradiation treatment for rectal cancer. METHODS AND MATERIALS 66 patients treated at the Brigham & Womens Hospital or Massachusetts General Hospital between 2006 and 2008 were included. Weekly during treatment, patients completed a questionnaire assessing severity of diarrhea, urgency, pain, cramping, mucus, and tenesmus. The association between dosimetric parameters and changes in overall GI symptoms from baseline through treatment was examined by using Spearmans correlation. Potential associations between these parameters and individual GI symptoms were also explored. RESULTS The amount of small bowel receiving at least 15 Gy (V15) was significantly associated with acute symptoms (p = 0.01), and other dosimetric parameters ranging from V5 to V45 also trended toward association. For the large bowel, correlations between dosimetric parameters and overall GI symptoms at the higher dose levels from V25 to V45 did not reach statistical significance (p = 0.1), and a significant association was seen with rectal pain from V15 to V45 (p < 0.01). Other individual symptoms did not correlate with small bowel or large bowel dosimetric parameters. CONCLUSIONS The results of this study using PROs are consistent with prior studies with physician-assessed acute toxicity, and they identify small bowel V15 as an important predictor of acute GI symptoms during 5-FU-based chemoradiation treatment. A better understanding of the relationship between radiation dosimetric parameters and PROs may allow physicians to improve radiation planning to optimize patient outcomes.

Improved MAGIC gel for higher sensitivity and elemental tissue equivalent 3D dosimetry.

PURPOSE Polymer-based gel dosimeter (MAGIC type) is a preferable phantom material for PET range verification of proton beam therapy. However, improvement in elemental tissue equivalency (specifically O/C ratio) is very desirable to ensure realistic time-activity measurements. METHODS Glucose and urea was added to the original MAGIC formulation to adjust the O/C ratio. The dose responses of the new formulations were tested with MRI transverse relaxation rate (R2) measurements. RESULTS The new ingredients improved not only the elemental composition but also the sensitivity of the MAGIC gel. The O/C ratios of our new gels agree with that of soft tissue within 1%. The slopes of dose response curves were 1.6-2.7 times larger with glucose. The melting point also increased by 5 degrees C. Further addition of urea resulted in a similar slope but with an increased intercept and a decreased melting point. CONCLUSIONS Our improved MAGIC gel formulations have higher sensitivity and better elemental tissue equivalency for 3D dosimetry applications involving nuclear reactions.

Clinical and treatment factors associated with vaginal stenosis after definitive chemoradiation for anal canal cancer

PURPOSE We sought to evaluate the incidence of vaginal stenosis (VS) and identify clinical and treatment factors that predict for VS in female patients with anal cancer treated with definitive chemoradiation. METHODS AND MATERIALS The cohort included 95 consecutive women receiving definitive chemoradiation between 2003 and 2012. All but 1 received intensity modulated radiation therapy; median primary tumor dose 50.4 Gy (range, 41.4-60). A modified National Cancer Institute Common Terminology Criteria for Adverse Events version 4 was used to score VS based on the medical record description of dyspareunia, pain with dilator use, vaginal dryness, or difficult pelvic examination. Ordered logistic regression was performed to assess VS predictors. RESULTS Median age was 60.4 years (range, 19-97). With median follow-up of 2.5 years, 70 women (74%) had adequate information to assess VS. Of these, VS grade distribution was 21.4% grade 0, 14.3% grade 1, 27.1% grade 2, and 37.1% grade 3. By multivariable ordered logistic regression, younger age (P = .02), higher tumor dose (P = .06), and earlier treatment year (P = .04) were associated with higher grade of VS. CONCLUSIONS VS is a common late complication in women treated definitively with chemoradiation for anal canal cancer. Younger age, higher tumor dose, and earlier year of treatment were associated with a higher grade of stenosis. Prospective investigation into patient reported outcomes is warranted, including sexual function and VS prevention strategies to better understand its effect on long-term survivorship.