LEAD BY EXAMPLE: Evaluation of an NCCN and ASCO guideline-based virtual weight loss and healthy lifestyle intervention on providers and staff members at a comprehensive cancer center

e24045

Background: Obesity is a leading cause of preventable death in the United States. The incidence of most obesity associated malignancies are increasing. Novel interventions to combat the obesity epidemic are greatly needed. Here we investigate the effect of a virtual clinical intervention on medical providers & other medical staff at a comprehensive cancer center. Methods: Physicians (MD), nurses (RN), & other medical staff (MS) were enrolled in an IRB approved, prospective single arm clinical trial. We assessed the effect of NCCN & ASCO guideline recommendations for weight loss & healthy lifestyle on overweight (OW) & obese (OB) providers & medical staff. Primary outcome: to assess change in body mass index (BMI) over a 3-month (mo.) intervention. Secondary outcomes: To assess changes in nutrition and exercise habits over time b) evaluate other lifestyle factors over time: stress, self-image, barriers to weight loss. Participants (Pts) filled out two 16 question (Q) pre & post survey (at 1, 90 days) relating to study outcomes. The virtual intervention consisted of giving information & advice over 3 months: A comprehensive handout e-mailed on day 1 + Motivational/info e-mails q 2 weeks/3 mo. Statistical analysis: students' paired T test used to compare changes in weight & survey responses day 0-90. P- value α = 0.05. Inclusions: age > 18 yo males & females, MD, RN, ARNP, & MS who are OW (BMI > 25Kg/m2) or OB (BMI > 30Kg/m2). Exclusions: non-OW/OB, Pts with uncontrolled cardiovascular, pulmonary, orthopedic, or cerebrovascular disease, pregnancy. Results: 106 participants enrolled; 26 subjects completed study. Demographics: 6/26 = 23% (MD/ARNP), 12/26 = 46% (RN), 8/26 = 31% (MS). 4/26 = 15% male, 22/26 = 85% female, µ age 45 (25-67). 3/26 = 12% Asian, 5/26 = 19% Black, 18/26 = 69% White. 100% not Hispanic. µ BMI = 33.9 kg/m2 (25.1-44.5). Intervention: 26/26 (100%) Pts lost weight/3 mo., µ Δ kg = -5.2kg (p < 0.0001), µ Δ BMI = - 1.67 kg/m2 (p = 0.002). Survey results: Significant improvements were seen in: self-image (p = 0.0012), physical activity (p < 0.0001), healthy diet (p < 0.0001), days/week exercise (p = 0.0008), µ Δ minutes exercise/week = +65 min/week (p = 0.0046), decreased stress levels (p < 0.0001). Limitations: significant participant drop out seen. Conclusions: All participants who completed the study lost weight & improved healthy lifestyle parameters. To our knowledge this is the first all virtual clinical weight loss & lifestyle intervention executed. Also, this is the first weight loss & lifestyle intervention executed in providers. Our intervention was cost effective, easy to execute, & warrants further study in both medical staff & patient populations. Last, this novel virtual intervention is highly relevant during the covid 19 pandemic due to social distancing requirements.

Randomized, double-blind, placebo-controlled phase II study of istiratumab (MM-141) plus nab-paclitaxel and gemcitabine versus nab-paclitaxel and gemcitabine in front-line metastatic pancreatic cancer (CARRIE)

BACKGROUND

Preclinical data suggest that dual blockade of the insulin-like growth factor-1 receptor (IGF-1R) and HER3 pathways has superior activity to IGF-1R blockade alone in pancreatic ductal adenocarcinoma (PDAC). We tested whether istiratumab, an IGF-1R- and ErbB3-bispecific antibody, can enhance the efficacy of standard of care (SOC) chemotherapy in patients with metastatic PDAC selected for high IGF-1 serum levels.

PATIENTS AND METHODS

CARRIE was an international, randomized, double-blind, placebo-controlled phase II study for patients with previously untreated metastatic PDAC. In part 1, 10 patients were evaluated for pharmacokinetics and safety. In part 2, patients with high free serum IGF-1 levels were randomized 1 : 1 to receive either istiratumab [2.8 g intravenously (i.v.) every 2 weeks] or placebo combined with gemcitabine/nab-paclitaxel at approved dose schedule. The co-primary endpoints were progression-free survival (PFS) in patients with high IGF-1 levels and PFS in patients with both high serum IGF-1 levels and heregulin (HRG)+ tumors. Key secondary endpoints were overall survival (OS), objective response rate (ORR) by RECIST v.1.1, and adverse events (AEs) rate.

RESULTS

A total of 317 patients were screened, with 88 patients randomized in part 2 (experimental arm n = 43; control n = 45). In the high IGF-1 cohort, median PFS was 3.6 and 7.3 months in the experimental versus control arms, respectively [hazard ratio (HR) = 1.88, P = 0.027]. In the high IGF-1/HRG+ subgroup (n = 44), median PFS was 4.1 and 7.3 months, respectively (HR = 1.39, P = 0.42). Median OS and ORR for the overall population were similar between two arms. No significant difference in serious or grade ≥3 AEs was observed, although low-grade AEs leading to early discontinuation were higher in the experimental (39.5%) versus control arm (24.4%).

CONCLUSIONS

Istiratumab failed to improve the efficacy of SOC chemotherapy in this patient setting. High serum IGF-1 levels did not appear to be an adverse prognostic factor when compared with non-biomarker-selected historic controls.

CLINICAL TRIAL REGISTRATION NUMBERS

ClinicalTrials.gov: NCT02399137; EUDRA CT: 2014-004572-34.

Pembrolizumab (P) in patients (Pts) with colorectal cancer (CRC) with high tumor mutational burden (HTMB): Results from the Targeted Agent and Profiling Utilization Registry (TAPUR) Study

133

Background: TAPUR is a phase II basket study evaluating anti-tumor activity of commercially available targeted agents in pts with advanced cancers with genomic alterations. Results in a cohort of CRC pts with HTMB treated with P are reported. Methods: Eligible pts had advanced CRC, no standard treatment (tx) options, measurable disease, ECOG PS 0-1, and adequate organ function. Genomic testing was performed in CLIA-certified, CAP-accredited site selected labs. Pts had HTMB, defined as ≥9 mutations/megabase (Muts/Mb) by a FoundationOne test (n=26) or other tests (n=2) approved by the Molecular Tumor Board. Pts with MSI-H tumors were ineligible. Dosing of P was 2 mg/kg (n=8) or 200 mg (n=20) IV over 30 mins, every 3 wks. Simon two-stage design was used to test a null rate of 15% vs. 35% (power = 0.85; α = 0.10). If ≥2 of 10 pts in stage 1 have disease control (DC) (objective response (OR) or stable disease at 16+ wks according to RECIST (SD16+)), 18 more pts enrolled. If ≥7 of 28 pts have DC, the tx is worthy of further study. Secondary endpoints are progression-free survival (PFS), overall survival (OS) and safety. Results: Twenty-eight pts enrolled from June 2017 to November 2018; 1 pt was ineligible and excluded. HTMB ranged from 9 to 54 Muts/Mb. Table (N=27) summarizes demographics and outcomes. Tumor MS status was reported stable for 25 pts, ambiguous for 1 pt, and not available for 1 pt. One PR (MS stable and 10 Muts/Mb) and 7 SD16+ were observed for DC and OR rates of 28% (90% CI, 16% to 45%) and 4% (95% CI, 0% to 19%), respectively. 2 pts each had grade 3 AEs at least possibly related to P including abdominal infection, anorexia, colitis, diarrhea, fatigue, nausea, and vomiting; 1 also had SAE of acute kidney injury. Conclusions: Monotherapy with P showed anti-tumor activity in heavily pre-treated CRC pts with HTMB . Additional study is warranted to confirm the efficacy of P in this population. Clinical trial information: NCT02693535.

[Table: see text]

Clinical activity of avapritinib in ≥ fourth-line (4L+) and PDGFRA Exon 18 gastrointestinal stromal tumors (GIST)

826

Background: Targeting oncogenic KIT and PDGFRA mutations revolutionized treatment of patients (pts) with advanced GIST; however, nearly all pts succumb to resistant disease. Avapritinib is a potent and selective kinase inhibitor with broad activity against oncogenic KIT/PDGFRA mutants, including PDGFRA D842V and other primary or secondary resistance mutations. Results from the phase 1 NAVIGATOR (NCT02508532) study of avapritinib in pts with advanced GIST are presented. Methods: Adult pts with unresectable PDGFRA D842V or other mutant GIST who progressed on imatinib and ≥1 other tyrosine kinase inhibitor (TKI) were treated with oral, daily, continuous avapritinib. Adverse events (AE) and response by mRECIST 1.1 per central radiology were assessed. Overall population safety (30-600 mg starting doses) and efficacy in the response-evaluable 4L+ and PDGFRA Exon 18 (Ex 18) populations treated at the MTD (400 mg)/RP2D (300 mg) were analyzed. Results: As of 16 Nov 2018, 237 pts [172 KIT, 62 PDGFRA Ex 18 [56 D842V, 6 non-D842V), 2 PDGFRA N659K, 1 missing] were enrolled including 111 in the 4L+ population (primarily KIT, median 4 prior TKI) and 43 in the Ex 18 population (median 1 prior TKI). The 4L+ ORR was 22% [1 CR, 23 PR (1 pending)], and 52 SD with mDOR of 10.2 months (95% CI: 7.2–NE). The Ex 18 ORR was 86% [3 CR, 34 PR (1 pending)] and 5 SD; mDOR was not reached (95% CI: 11.3–NE). Most AEs were grade 1–2, most commonly nausea (63%), fatigue (58%), anemia (49%), periorbital edema (42%), diarrhea (40%), vomiting (40%), decreased appetite (38%), increased lacrimation (33%), peripheral edema (33%) and memory impairment (most common cognitive AE, 29%). 10% of pts discontinued due to a related AE. Grade 3–4 related AE ≥ 2% were anemia, fatigue, hypophosphatemia, hyperbilirubinemia, neutropenia, and diarrhea. Conclusions: Avapritinib has important clinical activity in pts with advanced GIST who have no effective therapies. The ORR and DOR of avapritinib in 4L+ exceeds that of approved 2nd and 3rd line therapies and shows impressive activity in D842V and other Ex 18 mutant PDGFRA GIST. Results suggest avapritinib has the potential to change the treatment paradigm of pts with advanced GIST. Clinical trial information: NCT02508532.

Pertuzumab plus trastuzumab (P+T) in patients (Pts) with colorectal cancer (CRC) with ERBB2 amplification or overexpression: Results from the TAPUR Study

132

Background: TAPUR is a phase II basket trial evaluating anti-tumor activity of commercially available targeted agents in pts with advanced cancers with genomic alterations. Results in a cohort of CRC pts with ERBB2 overexpression or amplification treated with P+T are reported. Methods: Eligible pts had advanced CRC, no standard treatment (tx) options, measurable disease, ECOG PS 0-2, and adequate organ function. Genomic testing was performed in CLIA-certified, CAP-accredited site selected labs. Pts had ERBB2 overexpression or amplification, or certain ERBB2 mutations. Recommended dosing after initial dosing was P, 420 mg IV over 30-60 mins every 3 weeks (wks) and T, 6 mg/kg over 30-60 mins every 3 wks. Simon two-stage design was used to test a null rate of 15% vs. 35% (power = 0.85; α = 0.10). If ≥2 of 10 pts in stage 1 have disease control (DC) (objective response (OR) or stable disease at 16+ wks per RECIST (SD16+)), 18 more pts enrolled. If ≥7 of 28 pts have DC, the tx is worthy of further study. Secondary endpoints are progression-free survival (PFS), overall survival (OS) and safety. Results: Twenty-eight pts enrolled from November 2016 to September 2018 were evaluable for efficacy and safety. Demographics and outcomes are summarized in Table. All pts had ERBB2 amplification; 1 also had an ERBB2 mutation. 79% of pts had at least 3 prior txs. Four PR and 10 SD16+ were observed for DC and OR rates of 50% (90% CI, 36% to 60%) and 14% (95% CI, 4% to 33%), respectively. Two pts had at least one grade 3 AE or SAE at least possibly related to P+T including anemia, infusion reaction, and left ventricular dysfunction. Conclusions: The combination of P+T showed anti-tumor activity in heavily pre-treated CRC pts with ERBB2 amplification . Additional analyses by RAS mutation status are pending. Further study is warranted to confirm efficacy of P+T in this population. Clinical trial information: NCT02693535.

[Table: see text]

Clinical activity of avapritinib in ≥ fourth-line (4L+) and PDGFRA Exon 18 gastrointestinal stromal tumors (GIST)

11022

Background: Targeting oncogenic KIT and PDGFRA mutations revolutionized treatment of patients (pts) with advanced GIST; however, nearly all pts succumb to resistant disease. Avapritinib is a potent and selective kinase inhibitor with broad activity against oncogenic KIT/PDGFRA mutants, including PDGFRA D842V and other primary or secondary resistance mutations. Updated results from the phase 1 NAVIGATOR (NCT02508532) study of avapritinib in pts with advanced GIST are presented. Methods: Adult pts with unresectable PDGFRA D842V or other mutant GIST who progressed on imatinib and ≥ 1 other tyrosine kinase inhibitor (TKI) were treated with oral, daily, continuous avapritinib. Adverse events (AE) and response by mRECIST 1.1 per central radiology were assessed. Safety from the overall population (30-600 mg doses) and efficacy in the response evaluable 4L+ and PDGFRA Exon 18 (Ex 18) populations treated at the MTD (400 mg)/RP2D (300 mg) were analyzed. Results: As of 16 Nov 2018, 237 pts [172 KIT, 62 PDGFRA Ex 18 (56 D842V, 6 non-D842V), 2 PDGFRA N659K, 1 missing] were enrolled including 111 in the 4L+ population (primarily KIT, median 4 prior TKI) and 43 in the Ex 18 population (median 1 prior TKI). The 4L+ ORR was 22% [1 CR, 23 PR (1 pending)], and 52 SD with median duration of response (mDOR) of 10.2 months (95% CI: 7.2-NE). The Ex 18 ORR was 86% [3 CR, 34 PR (1 pending)] and 5 SD; mDOR was not reached (95% CI: 11.3-NE). Most AE were grade 1-2, most commonly nausea (63%), fatigue (58%), anemia (49%), periorbital edema (42%), diarrhea (40%), vomiting (40%), decreased appetite (38%), increased lacrimation (33%), peripheral edema (33%) and memory impairment (most common cognitive AE, 29%). 10% of pts discontinued due to a related AE. Grade 3-4 related AE ≥ 2% were anemia, fatigue, hypophosphatemia, hyperbilirubinemia, neutropenia, and diarrhea. Conclusions: Avapritinib has important clinical activity in pts with advanced GIST who have no effective therapies. The ORR and DOR of avapritinib in 4L+ exceeds that of approved 2nd and 3rd line therapies and shows unprecedented activity in D842V and other Ex 18 mutant PDGFRA GIST. Results suggest avapritinib has the potential to change the treatment paradigm of pts with advanced GIST. Clinical trial information: NCT02508532.

Correlation between tumor mutation burden and response to immunotherapy

e14579

Background: The use of immunotherapy is exponentially increasing in treatment of patients with advanced solid tumors. However, the response rates vary significantly between different tumor types and even within same tumor type (e.g. in lung cancer approx. 1 in 4 patients respond to immunotherapy). In order to better identify patients that will respond to immunotherapy, several markers have been proposed. Tumor mutation burden (TMB) has emerged more recently as a quantitative marker that can help predict responses to immunotherapies across different cancers, including melanoma, lung cancer and bladder cancer. TMB is a measure of the overall number of somatic protein coding mutations occurring in the tumor specimen. Methods: We analyzed 54 consecutive patients treated with immunotherapy at our institution for which we had genomic sequencing (FoundationOne). There were 39 lung cases and 15 non-lung (GI, GU, sarcoma). For 30 cases we had TMB data. Favorable response was defined as stable disease or response to therapy at 3 months. The relationship between TMB and tumor response was explored using ROC analysis. Results: The probability of a favorable response to immunotherapy in our patient dataset was 57% (31/54 patients). Among the patients with known TMB 60% (18/30) had a favorable response (stable disease or response to therapy). The favorable response rate for tumors originating in the lung was 64% (25/39) and for non-lung primary tumors was 40% (6/15). The difference was not statistically significant, with p = 0.12. Higher TMB values were correlated with increased probability of a favorable response. ROC analysis demonstrated an Az of 74% for TMB values in differentiating between patients with and without a favorable response. A TMB cutoff value of 8 mutations/megabase yielded a sensitivity of 95% and a specificity of 58% for predicting favorable response. Conclusions: In our data base 57%of patients with different solid cancers had favorable response to immunotherapy, in second line and beyond .Higher TMB correlated with higher likelihood of response to immunotherapy, independent of the primary site of cancer.

LAPACT: An open-label, multicenter phase II trial of nab-paclitaxel (nab-P) plus gemcitabine (Gem) in patients (pts) with locally advanced pancreatic cancer (LAPC)

TPS477

Background: In pts with LAPC, more effective systemic therapies may be associated with improved local control, delay of metastasis, and overall survival (OS). The phase III MPACT trial in pts with metastatic PC demonstrated longer OS (median, 8.7 vs 6.6 mos; HR, 0.72; P < 0.001) and an ≈ 3-fold greater shrinkage of primary tumors with nab-P + Gem vs Gem alone (−22.15% vs −7.02%), raising the possibility of improved local PC control with nab-P + Gem. LAPACT will assess the efficacy and safety of nab-P + Gem in LAPC. Methods: LAPACT will enroll treatment-naive pts (planned n ≈ 110) in the United States, Canada, and Europe with Eastern Cooperative Oncology Group performance status ≤ 1, confirmed unresectable LAPC, no distant metastases, and adequate organ function. Pts with mixed-origin tumors, any other malignancy within 5 years, peripheral neuropathy grade > 1, or clinically significant ascites are ineligible. Pts will receive nab-P 125 mg/m2 + Gem 1000 mg/m2 on days 1, 8, and 15 of each 28-day cycle. Pts without progressive disease (PD) or unacceptable toxicity after 6 cycles will receive investigator’s choice of surgery, chemoradiotherapy, or continued nab-P + Gem. If a major response is observed, surgery may occur prior to completing 6 cycles of nab-P + Gem. The primary endpoint is time to treatment failure (TTF; time from first therapy dose to discontinuation due to PD, start of a new non–protocol-defined anti-cancer therapy, or death). The study design allows for 80% power at a 1-sided α of 0.05 to detect a 30% increase over the 5.1-month median TTF observed for nab-P + Gem in the MPACT study. The secondary endpoints are disease control rate (DCR) after 6 cycles, overall response rate, progression-free survival, OS, safety, and quality of life. The exploratory endpoint is correlation of changes in circulating nucleic acids with PD and treatment response. An interim DCR analysis will occur after all pts have completed 6 cycles of nab-P + Gem, discontinued therapy due to PD, died, or started a new non–protocol-defined therapy before completing 6 cycles of therapy. Enrollment is ongoing (first pt enrolled in April 2015). Clinical trial information: NCT02301143.

MicroRNA-based assay for differential diagnosis of mesothelioma

e22079

Background: Malignant mesothelioma is an aggressive pleural neoplasm, strongly linked to environmental exposures such as asbestos. Mesothelioma can be difficult to differentiate from other tumors in the lung or pleura such as primary lung adenocarcinoma presenting with pleural effusion or metastatic adenocarcinoma from extrathoracic sites. We addressed the increasing need for accurate differential diagnosis of these tumors by developing a diagnostic assay based on expression levels of microRNAs, a family of small, non-coding RNAs whose tissue-specificity has proven applicability for identification of cancer tissue type and histology. Methods: We developed protocols for extraction of high-quality RNA that retain the microRNA fraction from FFPE tissue samples. Microarrays were used for initial profiling. qRT-PCR was used to validate results and to develop a diagnostic assay. Results: We identified microRNAs that are differentially expressed between mesothelioma, lung adenocarcinoma, and other confounding tumor types. A diagnostic assay (miRview™ meso) was developed, that utilizes qRT-PCR measurement of a small set of microRNAs to differentiate between mesothelioma and non-mesothelioma samples. After establishing this profile in more than 30 mesotheliomas and 200 samples of confounding tumors, the microRNA biomarkers were measured using a standardized protocol on a blinded test set. The assay had accuracy greater than 90% in differentiating mesothelioma from other confounding tumor types. More than ¾ of samples were classified with high confidence, and these samples were all correctly identified. Conclusions: MicroRNAs are emerging as effective cancer biomarkers. A robust and simple assay based on the expression level of a few microRNA biomarkers can accurately differentiate mesothelioma from other possible tumors in the lung and pleura. This assay provides an important new tool for diagnosing mesothelioma.

[Table: see text]

Use of microRNAs to distinguish small from non-small lung cancer

e22061

Background: Lung tumors are divided to two main classes: non-small cell lung cancer (NSCLC) that accounts for ∼80–85% of all lung primary tumors, and tumors from neuroendocrine origin - mainly small cell lung carcinoma and lung carcinoid. The classification of lung tumors can present a diagnostic challenge. New markers for different subtypes may aid in diagnosing difficult cases, can improve the accuracy of classification and could be important for selecting proper treatment. Here we studied the utility of microRNA as biomarkers for this differential diagnosis. MicroRNAs, a family of short non-coding regulatory RNAs, are highly tissue-specific and are well preserved in routinely prepared formalin-fixed, paraffin-embedded (FFPE) specimens, making them promising candidates as biomarkers for tissue and tumor classification. Methods: We used proprietary protocols for extracting high-quality RNA from FFPE samples. We used microRNA microarrays to profile more than a hundred samples from different histological subtypes of lung cancer including small cell, lung carcinoid and various types of NSCLC. Differential microRNA expression was verified using a microRNA qRT- PCR platform. Results: We found that several microRNAs are significantly differentially expressed between different subtypes of lung cancers. Specifically, using combinations of few microRNAs, we were able to accurately differentiate between neuroendocrine and NSCLC. Small cell and carcinoid tumors can be further distinguished using the signals of additional microRNAs, with very high sensitivity and specificity. Conclusions: Our results underscore the potential of microRNA expression for classification of tumor subtypes. We found that combinations of small numbers of microRNAs can successfully aid in the differential diagnosis of lung tumors, and provide a basis for the development of simple and reliable assays for clinical oncology.

[Table: see text]

Phase 2 study of talabostat/gemcitabine in Stage IV pancreatic cancer

4616

Background: Talabostat is an oral small molecule inhibitor of fibroblast activation protein (FAP), a stromal enzyme with collagenase and dipeptidyl peptidase activity. Talabostat also upregulates cytokine and chemokine production, resulting in immune stimulation. Talabostat is active in pancreatic tumor xenograft models and enhances the activity of gemcitabine in mice. Therefore, a clinical trial in patients with metastatic pancreatic cancer was initiated. Methods: Open-label, single-arm, Phase 2 study in 60 evaluable patients with Stage IV pancreatic cancer. Study treatment is administered in 4 x 4-week cycles; gemcitabine 1g/m2 weekly for 4 weeks in Cycle 1, then once weekly for 3 of 4 weeks. Talabostat 200mcg tablets are given BID for 6 days following each gemcitabine infusion; dose-escalation to 300mcg BID is allowed post-Cycle 1. Either agent alone or in combination can be continued beyond 4 cycles depending on tolerability. Eligible patients have measureable Stage IV pancreatic adenocarcinoma (per RECIST) are chemotherapy-naive, have a KPS ≥50, no CNS metastases, transaminases < 3 X ULN, and total bilirubin < 1.5 X ULN. Primary endpoint is 6-month survival with secondary endpoints of overall survival, PFS, pain, and quality-of-life. Tumor response or PD is assessed per RECIST. Results: As of the cut-off date, 46 patients (30 men, 16 women, median age 66 [range 43–88 years]) have received study treatment. Most patients (76%) were Stage IV at original diagnosis, and 72% have a KPS of 80 or higher. Ten of 21 evaluable patients treated as of June 30, 2006 meet 6-month survival. Median overall survival is currently estimated at 4.8 months (95% CI: 2.9, NE) in all 46 patients, and median PFS at 3.5 months (95% CI: 2.0, 4.9). Tumor responses have been reported in 3 patients: one CR and 2 PRs. Pain and QOL have not yet been analyzed. AEs are consistent with those of gemcitabine, with the exception of edema in 28.3% of patients. Grade 3 anemia, neutropenia, hyponatremia hyperbilirubinemia, and increased alk phos are reported in 2 patients each. No Grade 4 AEs have been reported in more than one patient. Conclusions: Talabostat/gemcitabine shows activity in metastatic pancreatic cancer and can be safety administered. Enrollment completed in early January 2007, and final results will be presented at the annual meeting.

No significant financial relationships to disclose.

Randomized phase II trial of three dosing schedules of nanoparticle albumin-bound paclitaxel with bevacizumab as first-line therapy for HER2-negative metastatic breast cancer: An initial interim safety report

1104

Background: Nanoparticle paclitaxel (NP) at 260mg/m2 every 3 weeks (q3wk) is more effective than standard paclitaxel (P) (Gradishar et al, JCO 2005). Weekly, uninterrupted administration of P is superior to q3wk P in MBC (Seidman et al, Proc ASCO 2004). When added to weekly P as 1st-line therapy for MBC, bevacizumab (B) improves response rate and progression-free survival (Miller et al, Proc ASCO 2005). We initiated a randomized phase II trial of NP given at 260mg/m2 q3wk (arm A) vs. 260mg/m2 q2wk with filgrastim (arm B) vs. 130mg/m2 weekly, all with B, as 1st-line therapy for patients (pts) with HER2- MBC. Methods: 66 of planned 225 pts have enrolled. After 31 pts had been randomized and treated, investigators concerned about possible differential neurotoxicity requested this early interim safety analysis. Median age is 54 (range 40–78). 83% are post-menopausal and 100% have visceral dominant disease. 68% had prior adjuvant or neo-adjuvant chemotherapy; 35% with taxanes. Results: With 170 cycles delivered (median: 4, range 1–15) 10 dose reductions have been necessary for NP (1 in A, 5 in B, 4 in C). No hypersensitivity reactions or dose interruptions have occurred for NP; 3 doses of B have been held due to hypertension. Significant preliminary antitumor activity has been noted in all arms. One grade 4 toxicity occurred in arm C, hyperglycemia. 15 grade 3 toxicities have been reported across all arms. Pts on arm A have experienced 3 grade 3 toxicities (30%): fatigue, neutropenia, and arthralgia with no grade 3 neurotoxicity. Pts on arm B have had 7 grade 3 toxicities (58%) with 3 pts experiencing grade 3 sensory neuropathy (25%) and others experiencing fatigue, neutropenia, anemia, esophagitis, dyspnea, and ataxia. 5 arm C pts experienced grade 3 toxicities (56%) including diarrhea, dehydration, mucositis, neutropenia, hypokalemia; 2 pts have had grade 3 sensory neuropathy (22%). Conclusions: This early safety analysis does not detect any statistically or clinically significant differences in grade 3 toxicity and all arms continue to accrue. The next protocol-specified safety analysis is expected in early 2007, with mature safety data for 60 pts. Updated results will be presented.

[Table: see text]

Efficacy of dronabinol alone and in combination with ondansetron versus ondansetron alone for delayed chemotherapy-induced nausea and vomiting

OBJECTIVE

To compare the efficacy and tolerability of dronabinol, ondansetron, or the combination for delayed chemotherapy-induced nausea and vomiting (CINV) in a 5-day, double-blind, placebo-controlled study.

RESEARCH DESIGN AND METHODS

Patients receiving moderately to highly emetogenic chemotherapy received dexamethasone (20 mg PO), ondansetron (16 mg IV) and either placebo or dronabinol (2.5 mg) prechemotherapy on day 1. Patients randomized to active treatment (dronabinol and/or ondansetron) also received dronabinol (2.5 mg) after chemotherapy on day 1. On day 2, fixed doses of placebo, dronabinol (10 mg), ondansetron (16 mg), or combination therapy were administered. On days 3-5, patients received placebo, flexible doses of dronabinol (10-20 mg), ondansetron (8-16 mg), or dronabinol and ondansetron (10-20 mg dronabinol, 8-16 mg ondansetron).

MAIN OUTCOME MEASURES

Total response (TR = nausea intensity <5 mm on visual analog scale, no vomiting/retching, no rescue antiemetic), nausea (occurrence and intensity) and vomiting/retching episodes.

RESULTS

Sixty-four patients were randomized; 61 analyzed for efficacy. TR was similar with dronabinol (54%), ondansetron (58%), and combination therapy (47%) versus placebo (20%). Nausea absence was significantly greater in active treatment groups (dronabinol, 71%; ondansetron, 64%; combination therapy, 53%) versus placebo (15%; p < 0.05 vs. placebo for all). Nausea intensity and vomiting/retching were lowest in patients treated with dronabinol. Active treatments were well tolerated. The low number of patients due to slow enrollment limits the interpretation of these data.

CONCLUSIONS

Dronabinol or ondansetron was similarly effective for the treatment of CINV. Combination therapy with dronabinol and ondansetron was not more effective than either agent alone. Active treatments were well tolerated.

Characterization of three PDI-like genes in Physcomitrella patens and construction of knock-out mutants

Plant genomes typically contain several sequences homologous to protein disulfide isomerase (PDI). PDI was first identified as an abundant enzyme in the endoplasmic reticulum, where it catalyzes the formation, reduction, and isomerization of disulfide bonds during protein folding. PDI-like proteins have also been implicated in a variety of other functions, such as the regulation of cell adhesion, and may act as elicitors of the autoimmune response in mammals. A PDI-like protein (RB60) was recently shown to be imported into chloroplasts in the unicellular green alga Chlamydomonas reinhardtii and a higher plant, Pisum sativum, where it associates with thylakoid membranes. This suggests that the different PDI-like proteins in plant and animals may have diverse biological roles. To begin to elucidate the roles of PDI-like proteins, we have cloned, characterized, and generated knock-out mutants for three PDI-like genes that have high, medium, and low levels of expression, respectively, in the moss Physcomitrella patens. Phylogenetic analysis indicates that the three PDI-like proteins cluster with RB60 and four proteins from Arabidopsis thaliana. They are typified by an N-terminal domain rich in negatively charged residues. The knock-out mutants, which are the first knock-outs available for PDI-like proteins in a multicellular organism, were found to be viable, indicating that the function of each single gene is dispensable, and suggesting that they may be functionally complementary.

The protein disulfide isomerase-like RB60 is partitioned between stroma and thylakoids in Chlamydomonas reinhardtii chloroplasts

Translation of psbA mRNA in Chlamydomonas reinhardtii chloroplasts is regulated by a redox signal(s). RB60 is a member of a protein complex that binds with high affinity to the 5'-untranslated region of psbA mRNA. RB60 has been suggested to act as a redox-sensor subunit of the protein complex regulating translation of chloroplast psbA mRNA. Surprisingly, cloning of RB60 identified high homology to the endoplasmic reticulum-localized protein disulfide isomerase, including an endoplasmic reticulum-retention signal at its carboxyl terminus. Here we show, by in vitro import studies, that the recombinant RB60 is imported into isolated chloroplasts of C. reinhardtii and pea in a transit peptide-dependent manner. Subfractionation of C. reinhardtii chloroplasts revealed that the native RB60 is partitioned between the stroma and the thylakoids. The nature of association of native RB60, and imported recombinant RB60, with thylakoids is similar and suggests that RB60 is tightly bound to thylakoids. The targeting characteristics of RB60 and the potential implications of the association of RB60 with thylakoids are discussed.

Recombination of engineered defective RNA species produces infective potyvirus in planta

Recombination occurred between viral genomes when squash plants were cobombarded with mixtures of engineered disabled constructs of a zucchini yellow mosaic potyvirus. Single and double recombinants were detected in the progeny. Genes involved in the recombination process and the mechanisms of recombination were studied in potyviruses for the first time.

Simple hand-held devices for the efficient infection of plants with viral-encoding constructs by particle bombardment

An efficient method for infection of plants with a cloned potyvirus by particle bombardment has been described (Gal-On et al., 1995). A simplified method is described now whereby a vaccuum chamber and helium propulsive gas are not required to achieve a high efficiency of infection. The new device-the 'HandGun'--is hand-held, and easily constructed from readily available materials. With this technique it is possible to bombard soft plants and seedings that do not survive particle bombardment by other devices. bombardment of C. pepo plants with a full length clone of zucchini yellow mosaic potyvirus results in approximately 100% infection at 100 pg cDNA per plant using air or helium to propel the microprojectiles. The HandGun is 10(5)-fold more efficient than mechanical inoculation. Tungsten and gold were found to be the most efficient materials tested for use as microprojectiles. Crude extracts of plasmids from E. coli were found to be effective, as well as column-purified cDNA. A functional, simple version of the HandGun--'the Blowpipe'--was also constructed, which does not require an electrically controlled valve. Plants can be inoculated with plant viruses from sap with the HandGun.

Particle bombardment drastically increases the infectivity of cloned DNA of zucchini yellow mosaic potyvirus

An infectious full-length cDNA clone of the RNA genome of the potyvirus zucchini yellow mosaic virus (ZYMV) was constructed under the control of the cauliflower mosaic virus 35S promoter. All squash, cucumber, melon and watermelon plants inoculated with the cloned cDNA of ZYMV by particle bombardment become infected. Bombardment technology is 10(6)-fold more effective than mechanical inoculation. Due to the great increase in efficiency, ineffective constructs now became infective (i.e. cDNA under the control of the 35S promoter without the NOS terminator; with an addition of 127 nucleotides at the 5' end of the viral cDNA; uncapped transcripts), and the infectivity of capped-transcripts was maximized. Inoculation by particle bombardment produced visual symptoms rapidly (3-4 days), allowing the detection of viral coat protein and virions after 2 and 3 days in systemically infected leaves and inoculated cotyledons respectively.