Quantitative proteomic analysis of HER2 protein expression in PDAC tumors

Metastatic pancreatic adenocarcinoma (PDAC) is the third leading cause of cancer-related death in the United States, with a 5-year survival rate of only 11%, necessitating identification of novel treatment paradigms. Tumor tissue specimens from patients with PDAC, breast cancer, and other solid tumor malignancies were collected and tumor cells were enriched using laser microdissection (LMD). Reverse phase protein array (RPPA) analysis was performed on enriched tumor cell lysates to quantify a 32-protein/phosphoprotein biomarker panel comprising known anticancer drug targets and/or cancer-related total and phosphorylated proteins, including HER2Total, HER2Y1248, and HER3Y1289. RPPA analysis revealed significant levels of HER2Total in PDAC patients at abundances comparable to HER2-positive (IHC 3+) and HER2-low (IHC 1+ /2+ , FISH-) breast cancer tissues, for which HER2 screening is routinely performed. These data support a critical unmet need for routine clinical evaluation of HER2 expression in PDAC patients and examination of the utility of HER2-directed antibody-drug conjugates in these patients.

Effectiveness of an Electronic Medical Record-Based Recognition Tool for the Identification of Incidental Pulmonary Nodules

BACKGROUND

Incidental pulmonary nodules (IPNs) are lung nodules detected on imaging studies performed for an unrelated reason. Approximately 1.6 million IPNs are detected in the United States every year. Unfortunately, close to 1.1 million (69%) of these IPNs are not managed with appropriate follow-up care. The goal of this study was to assess the utility of a noncommercial electronic medical record (EMR)-based IPN keyword recognition program in identifying IPNs and the ability of lung navigators to communicate these findings to patients.

METHODS

This is a observational, implementation study aimed identify IPNs using an EMR-based protocol and to relay results of findings to patients. The patient population included patients 16 and older undergoing computed tomography (CT) chest, CT chest/abdomen, CT angiogram chest, CT chest/abdomen/pelvis, and chest radiography through the radiology department within a large community tertiary medical campus between June 2019 and August 2020. EPIC EMR were queried using criteria designed to find IPNs. A lung navigator reviewed these cases and sorted them into categories based on their size and risk status. After identification of risk factors, actions were taken to directly communicate results to patients.

RESULTS

Seven hundred and fifty-three patients were found to have true IPNs without a history of active malignancy involving the lung. On the basis of radiographic measurements, 60% of the nodules identified were <6 mm, 17% were between 6 and 8 mm, 22% were >8 mm, and 12% were deemed nodular opacities. Lung navigators were able to contact a total of 637 (87%) individuals with IPNs and results were directly communicated. Of the 637 patients identified to have an IPN, a total of 12 (2%) cancers were diagnosed.

CONCLUSION

We have here demonstrated that the development of an EMR-based keyword recognition platform for the identification of IPNs is a useful and successful tool for communication of IPN findings to patients using lung navigators.

Safety of Nivolumab Added to Chemoradiation Therapy Platforms for Intermediate and High-Risk Locoregionally Advanced Head and Neck Squamous Cell Carcinoma: RTOG Foundation 3504

PURPOSE

Programmed death-1 immune checkpoint blockade improves survival of patients with recurrent/metastatic head and neck squamous cell carcinoma (HNSCC), but the benefits of addition to (chemo)radiation for newly diagnosed patients with HNSCC remain unknown.

METHODS AND MATERIALS

We evaluated the safety of nivolumab concomitant with 70 Gy intensity modulated radiation therapy and weekly cisplatin (arm 1), every 3-week cisplatin (arm 2), cetuximab (arm 3), or alone for platinum-ineligible patients (arm 4) in newly diagnosed intermediate- or high-risk locoregionally advanced HNSCC. Patients received nivolumab from 2 weeks prior to radiation therapy until 3 months post-radiation therapy. The primary endpoint was dose-limiting toxicity (DLT). If ≤2 of the first 8 evaluable patients experienced a DLT, an arm was considered safe. Secondary endpoints included toxicity and feasibility of adjuvant nivolumab to 1 year, defined as all 7 additional doses received by ≥4 of the first 8 evaluable patients across arms.

RESULTS

Of 39 patients (10 in arms 1, 3, 4 and 9 in arm 2), 72% had T3-4 tumors, 85% had N2-3 nodal disease, and 67% had >10 pack-years of smoking. There were no DLTs in arms 1 and 2, 1 in arm 3 (mucositis), and 2 in arm 4 (lipase elevation and mucositis in 1 and fatigue in another). The most common grade ≥3 nivolumab-related adverse events were lipase increase, mucositis, diarrhea, lymphopenia, hyponatremia, leukopenia, fatigue, and serum amylase increase. Adjuvant nivolumab was feasible as defined in the protocol.

CONCLUSIONS

Concomitant nivolumab with the 4 tested regimens was safe for patients with intermediate- and high-risk HNSCC, and subsequent adjuvant nivolumab was feasible as defined (NCT02764593).

Interplay of Immunosuppression and Immunotherapy Among Patients With Cancer and COVID-19

Importance

Cytokine storm due to COVID-19 can cause high morbidity and mortality and may be more common in patients with cancer treated with immunotherapy (IO) due to immune system activation.

Objective

To determine the association of baseline immunosuppression and/or IO-based therapies with COVID-19 severity and cytokine storm in patients with cancer.

Design, Setting, and Participants

This registry-based retrospective cohort study included 12 046 patients reported to the COVID-19 and Cancer Consortium (CCC19) registry from March 2020 to May 2022. The CCC19 registry is a centralized international multi-institutional registry of patients with COVID-19 with a current or past diagnosis of cancer. Records analyzed included patients with active or previous cancer who had a laboratory-confirmed infection with SARS-CoV-2 by polymerase chain reaction and/or serologic findings.

Exposures

Immunosuppression due to therapy; systemic anticancer therapy (IO or non-IO).

Main Outcomes and Measures

The primary outcome was a 5-level ordinal scale of COVID-19 severity: no complications; hospitalized without requiring oxygen; hospitalized and required oxygen; intensive care unit admission and/or mechanical ventilation; death. The secondary outcome was the occurrence of cytokine storm.

Results

The median age of the entire cohort was 65 years (interquartile range [IQR], 54-74) years and 6359 patients were female (52.8%) and 6598 (54.8%) were non-Hispanic White. A total of 599 (5.0%) patients received IO, whereas 4327 (35.9%) received non-IO systemic anticancer therapies, and 7120 (59.1%) did not receive any antineoplastic regimen within 3 months prior to COVID-19 diagnosis. Although no difference in COVID-19 severity and cytokine storm was found in the IO group compared with the untreated group in the total cohort (adjusted odds ratio [aOR], 0.80; 95% CI, 0.56-1.13, and aOR, 0.89; 95% CI, 0.41-1.93, respectively), patients with baseline immunosuppression treated with IO (vs untreated) had worse COVID-19 severity and cytokine storm (aOR, 3.33; 95% CI, 1.38-8.01, and aOR, 4.41; 95% CI, 1.71-11.38, respectively). Patients with immunosuppression receiving non-IO therapies (vs untreated) also had worse COVID-19 severity (aOR, 1.79; 95% CI, 1.36-2.35) and cytokine storm (aOR, 2.32; 95% CI, 1.42-3.79).

Conclusions and Relevance

This cohort study found that in patients with cancer and COVID-19, administration of systemic anticancer therapies, especially IO, in the context of baseline immunosuppression was associated with severe clinical outcomes and the development of cytokine storm.

Trial Registration

ClinicalTrials.gov Identifier: NCT04354701.

Remote Home Monitoring of Patients With Cancer During the COVID Pandemic: A Pilot Study

PURPOSE

The COVID-19 pandemic has posed significant challenges in the care of patients with cancer, including how to manage outpatients who are COVID-positive but do not require hospitalization. We explored the use of a remote patient monitoring (RPM) program to care for such outpatients.

METHODS

Consecutive patients who were tested for COVID-19 because of symptom onset but were clinically stable were offered enrollment into a pilot RPM program. Patients were provided equipment for vital sign measurements and a computer tablet to enter results three times per day. The results were monitored centrally by clinical staff. The goal was to closely monitor patients and escalate care as warranted.

RESULTS

Between March and June of 2020, 29 patients were approached and 26 were enrolled. The mean age was 57 years old (range, 30-88), 14 were women, and patients remained in the program for an average of 16 days (range, 2-63). Twenty-four patients (83%) were on active anticancer therapy. During that time period, only one patient was admitted to the hospital for worsening respiratory symptoms. The percentage of days during which at least one set of data and all three sets of data were entered was 97.2% and 65.7%, respectively. There was no association between the demographic factors of age, sex, or the reason for being monitored with the level of engagement (P > .05).

CONCLUSION

In this pilot study, patients with cancer were readily enrolled in a remote home monitoring program. Monitoring was feasible, and there was a high rate of engagement with the program. The role of RPM should be further tested as the COVID pandemic continues.

Concurrent BRAFV600E and BRCA mutations in microsatellite stable (MSS) metastatic colorectal cancer (mCRC): Prevalence and case series of mCRC (pts) with prolonged overall survival (OS)

3561

Background: BRAF V600E+, MSS mCRC patients comprise up to 10% of advanced CRC. They have a poor prognosis with median survivals typically <1 year. Despite use of multi-agent first-line chemotherapy regimens and combination targeted therapies, outcomes are still poor. In our Institutional Molecular Tumor Board database, we identified 3 consecutive mCRC pts with MSS/ BRAF V600E who also had a BRCA1 or BRCA2 co-mutation and had prolonged overall survival. Prior studies suggested that BRCA mutations are uncommon in CRC and we queried the Foundation Medicine (FM) genomic database to evaluate the prevalence of these cases as well as those with co-mutations in other homologous recombination genes. Methods: 36,966 CRC pts were sequenced by FMI using hybrid capture comprehensive genomic profiling (CGP) to evaluate all classes of genomic alterations (GA) for pathogenic BRAF mutations and/or a mutation in BRCA1/2 or a co-mutation in other homologous recombination (HR) genes ( BARD1, CDK12, FANCL, PALB2, ATM, RAD54L, CHEK2, BRAF, BRIP1, RAD51D, RAD51C, RAD51B, CHEK1). Selected cohort analysis were BRAF V600E co-mutated with BRCA1 and BRCA2, separated into MSI-H and MSS cohorts. The clinicopathological features and genomic loss of heterozygosity (gLOH) of those with a BRAF V600E and a BRCA1/BRCA2 mutation are described along with 3 consecutive cases of CRC patients, identified through the Inova Schar Cancer Institute (ISCI) molecular tumor board (MTB) registry, whom had prolonged OS. Results: Of 36,966 colorectal cancer pts, 6.6% were BRAF V600E+ and 1.5% had any co-occurring HR gene mutation(s) with 0.6% having co-mutations of BRAF V600E and BRCA1/2. BRCA co-mutations were higher in MSI-High BRAF V600E, however 24.1% of these occurred in MSS BRAF V600E. BRCA1 co-mutated was more commonly associated with MSS BRAF V600E and was associated with a higher gLOH than MSI-H BRAF V600E (18.7% vs 2.8%; p <0.001 ). In our institutional MTB database, (3/241;1.2%) CRC patients were MSS, BRAF V600E+ with BRCA1 or BRCA2 co-mutations, one confirmed germline and 2 somatic in origin, and had average gLOH of 21.4% with overall survivals of 72+(alive), 17+(alive), and 30 months, respectively. Conclusions: Co-existence of BRAF V600E/ BRCA1/2 may represent a unique subset of advanced MSS CRC that may have a better prognosis and represent an opportunity to test novel targeted therapies. Larger prospective clinical validation trials in this subset is warranted.[Table: see text]

Efficacy and safety of larotrectinib in patients with TRK fusion gastrointestinal cancer

824

Background: Tropomyosin receptor kinase (TRK) fusions arise from rearrangements of the neurotrophic tyrosine receptor kinase ( NTRK) 1, 2, or 3 genes and an unrelated gene, creating constitutively active oncogenic drivers that have been detected in a range of adult and pediatric malignancies, but are generally rare in patients with gastrointestinal (GI) cancer. Larotrectinib is a selective TRK inhibitor approved for the treatment of adult and pediatric patients with TRK fusion cancer. Here, we report efficacy and safety data for patients with TRK fusion GI tumors. Methods: Patients with a TRK fusion GI cancer treated with larotrectinib in a phase II clinical trial, NAVIGATE (NCT02576431), were included in this analysis. Larotrectinib was administered at 100 mg twice daily, until disease progression, unacceptable toxicity, death, or withdrawal. Response was assessed by the investigator using RECIST v1.1. Results: As of February 19, 2019, 14 patients with TRK fusion GI cancer (median age 68 y, range 32–84 y) were enrolled. GI tumor types were colon (8), cholangiocarcinoma (2), pancreas (2), appendix (1), and hepatic (1). Fusions involved NTRK1 (n = 12) and NTRK3 (n = 2). Nine patients had ≥2 prior lines of therapy. The best response on last prior therapy was 1 partial response (PR). Overall best responses on larotrectinib were: colon cancer, 4 patients had a PR and 4 had stable disease (SD); pancreatic cancer, 1 patient had a PR and 1 had SD; cholangiocarcinoma, 1 patient had a PR and 1 had progressive disease; appendix cancer, 1 patient had SD; response in 1 patient with hepatic cancer was not determined. Median time to response was 1.8 months (range 1.7–2.1). With 5 patients ongoing and censored, the median progression free survival was 5.3 months (95% CI 2.2–9.0). Median overall survival was 33.4 months (95% CI 2.8–36.5). Larotrectinib was well tolerated, with most adverse events being grade 1 or 2. Conclusions: Although the sample size is limited, there is evidence of clinical activity with larotrectinib in TRK fusion GI cancer, with a manageable safety profile. TRK fusion GI cancer may represent an under-diagnosed subset of patients with viable treatment options. Clinical trial information: NCT02576431.

Association of Ancestral Genetic Admixture and Excess Weight at Twelve Months of Age

Background/Objective: Understanding the influence of genetically determined ancestry may give insight into the disparities of obesity seen in different ethnic groups beginning at a very early age. Aim: To investigate the relationship between children's ancestral genetic proportions and excess weight at 12 months of age. Methods: Eight hundred twenty-one 12-month-old children were included in this cross-sectional study. Their genetic admixture was estimated using the ancestry and kinship tool kit by projecting the samples into the 1000 Genomes principal component database. Weight-for-length percentile (WFLP) at 12 months of age was categorized as <95th percentile or ≥95th percentile. Multiple logistic regression analysis was performed to calculate odds ratios (ORs) with 95% confidence intervals (CIs) for the association of admixture proportions, including European (EUR), admixed American (AMR), African (AFR), South Asian (SAS), and East Asian (EAS) populations, with WFLP categories, adjusting for maternal education, birth weight, frequency of breastfeeding, and juice consumption. Results: Eight hundred twenty-one children were included; WFLP <95th percentile = 671 (81.7%) and WFLP ≥95th percentile = 150 (18.3%). Crude ORs showed that the EUR admixture was protective [OR 0.45 (95% CI 0.27-0.74)], whereas AMR [OR 3.85 (95% CI 1.92-7.70)] and AFR [OR 5.70 (95% CI 2.19-14.85)] admixtures were positively associated with excess weight. After adjusting for confounding variables, only the AFR admixture was associated with WFLP ≥95th percentile [OR 7.38 (95% CI 2.31-23.59)]. Conclusions: AFRs remain associated with early excess weight after accounting for confounding variables, suggesting that this ancestral genetic background may contribute to the differences seen in early childhood obesity.

Conditional Reprogramming for Patient-Derived Cancer Models and Next-Generation Living Biobanks

Traditional cancer models including cell lines and animal models have limited applications in both basic and clinical cancer research. Genomics-based precision oncology only help 2-20% patients with solid cancer. Functional diagnostics and patient-derived cancer models are needed for precision cancer biology. In this review, we will summarize applications of conditional cell reprogramming (CR) in cancer research and next generation living biobanks (NGLB). Together with organoids, CR has been cited in two NCI (National Cancer Institute, USA) programs (PDMR: patient-derived cancer model repository; HCMI: human cancer model initiatives. HCMI will be distributed through ATCC). Briefly, the CR method is a simple co-culture technology with a Rho kinase inhibitor, Y-27632, in combination with fibroblast feeder cells, which allows us to rapidly expand both normal and malignant epithelial cells from diverse anatomic sites and mammalian species and does not require transfection with exogenous viral or cellular genes. Establishment of CR cells from both normal and tumor tissue is highly efficient. The robust nature of the technique is exemplified by the ability to produce 2 × 106 cells in five days from a core biopsy of tumor tissue. Normal CR cell cultures retain a normal karyotype and differentiation potential and CR cells derived from tumors retain their tumorigenic phenotype. CR also allows us to enrich cancer cells from urine (for bladder cancer), blood (for prostate cancer), and pleural effusion (for non-small cell lung carcinoma). The ability to produce inexhaustible cell populations using CR technology from small biopsies and cryopreserved specimens has the potential to transform biobanking repositories (NGLB: next-generation living biobank) and current pathology practice by enabling genetic, biochemical, metabolomic, proteomic, and biological assays, including chemosensitivity testing as a functional diagnostics tool for precision cancer medicine. We discussed analyses of patient-derived matched normal and tumor models using a case with tongue squamous cell carcinoma as an example. Last, we summarized applications in cancer research, disease modeling, drug discovery, and regenerative medicine of CR-based NGLB.

EPG5 Variants with Modest Functional Impact Result in an Ameliorated and Primarily Neurological Phenotype in a 3.5-Year-Old Patient with Vici Syndrome

Congenital disorders of autophagy are multisystem disorders with significant neurological involvement. Ectopic p-granules protein 5 (EPG5)-associated Vici syndrome is a prototypical congenital disorder of autophagy and presents with the cardinal features of agenesis of the corpus callosum, cataracts, cardiomyopathy, immunodeficiency, and oculocutaneous hypopigmentation. The majority of EPG5 variants leading to Vici syndrome are null alleles with only a few missense variants published to date. Here we report a 3.5-year-old male with compound heterozygous EPG5 variants [NM_020964.2: c.772G > T/c.5943-9_5943-5del]. His clinical presentation deviates notably from classic Vici syndrome with a lack of hypopigmentation, cataracts, immunodeficiency, cardiomyopathy, or failure to thrive. Neurological manifestations within the known disease spectrum include early-onset global developmental delay, hypotonia, and postnatal microcephaly. Seizures, hearing loss, or optic nerve atrophy are absent, however. Magnetic resonance imaging demonstrates a thin but fully formed corpus callosum. Based on the ameliorated and primarily neurological phenotype, we hypothesized that the functional impact of the EPG5 variants present would be milder with a higher amount of residual EPG5 expression. Analyses of EPG5 messenger ribonucleic acid (mRNA) in the patient and his parents were performed to examine expression level and splicing; mRNA from a healthy control and a patient with classic Vici syndrome was also included. Aberrant splicing due to the intronic mutation was detected, but no loss of expression. In contrast, we observed a 50% reduction in mRNA expression in classic Vici syndrome patient fibroblasts. These results support a model of disease severity, which correlates to the dosage of EPG5 expression.

Safety and disease control achieved with the addition of nivolumab (Nivo) to chemoradiotherapy (CRT) for intermediate (IR) and high-risk (HR) local-regionally advanced head and neck squamous cell carcinoma (HNSCC): RTOG Foundation 3504

6073

Background: Nivo, which inhibits the programmed death-1 (PD-1) receptor, improved survival for pts with platinum-refractory recurrent/metastatic HNSCC. A clinical trial evaluated the safety of adding nivo to 4 standard intensity modulated (chemo) radiotherapy (RT) regimens (see table) for pts with newly diagnosed IR/HR HNSCC. Primary endpoint was safety and feasibility. Methods: Eligibility included IR (p16+ oropharynx [op], T1-2N2b-N3/T3-4N0-3, >10 pack-years [pys], or T4N0-N3/T1-3N3, ≤10 pys) & HR HNSCC (oral cavity, larynx, hypopharynx, p16- op, T1-2N2a-N3/T3-4N0-3). 10 pts/arm (8 evaluable; 0-2/8 DLTs acceptable). Nivo (dose & schedule varied per arm) started 2 wks pre-RT & continued 3 months post-RT. Feasibility of adjuvant nivo months 3-12 post-RT defined as ≥4 of 8 pts/arm received 7 doses. Arm 4 limited to age ≥70, Zubrod performance status (PS) 2, CrCl <50 ml/min, grade ≥2 hearing loss or ≥ grade 3 neuropathy. Results: Characteristics of 39/40 treated pts: median age 62, 79% male, 49% PS0, 38% HR, 67% >10 pys, 62% p16+ op, 72% T3-4, 85% N2-3. Grade ≥3 nivo-related AEs: adrenal insufficiency, diarrhea-3, anemia, fatigue-2, mucositis-3, nausea, vomiting, lipase increase-6, amylase increase-2, lymphocyte/neutrophil/WBC decrease-4, hyponatremia-3, anorexia, maculo-papular rash. SAE in 4/10, 4/9, 5/10 & 4/10. DLTs, adjuvant chemo feasibility, median follow-up (mo), progression or death events per arm shown in table. Conclusions: Nivo concomitant with all (chemo)RT regimens was safe for patients with newly diagnosed IR/HR HNSCC but adjuvant nivo was infeasible after high-dose cisplatin or in cisplatin-ineligible patients ( NCT02764593 ). Preliminary data on progression/death is provided. Acknowledgements: Support for this study was provided by Bristol-Myers Squibb Company. Clinical trial information: NCT02764593. [Table: see text]

Clinical pharmacogenomic testing impacts therapy decisions and supportive medication choices in breast cancer

569

Background: Pharmacogenomics, the study of the interaction between the patient’s genome and therapeutic drug response, evaluates the associations between efficacy and toxicity through analysis of drug metabolizing enzymes. As personalized medicine advances to the forefront of cancer care, pharmacogenomics can evaluate the individual’s ability to metabolize key medications in breast cancer treatment including anti-emetics, opioids, and tamoxifen. Women who do not achieve optimal levels of the active metabolites of tamoxifen are at higher risk of recurrence. Patients on chemotherapy who do not respond to anti-emetics can suffer from nausea and vomiting resulting in dehydration and hospitalization. This project evaluates the feasibility and therapeutic impact of real time pharmacogenomics in a selection of patients at the Inova Schar Cancer Institute (ISCI). Methods: An interdisciplinary team was created through the ISCI and the Inova Translational Medicine Institute to implement cheek swab based pharmacogenomic testing in 50 new patients undergoing mastectomy or neoadjuvant chemotherapy for breast cancer. Study patients were assessed for genotypic variability of key CYP enzymes and resulting impact on anti-emetic choices, perioperative pain control, and tamoxifen use. Results: Data was collected in a RedCap database. The 50 women enrolled were ages 28-83. Cheek swabs were performed in clinic and median turn around time was 7 days. 24 distinct genotypes were found in the 50 patients. 20% had abnormal CYP2D6 phenotypes indicating abnormalities in tamoxifen metabolism. 28% of patients had results leading to changes in dose or medication choice of perioperative pain control. 6% of patients had a CYP2D6 ultra-rapid metabolizer phenotype and were given granisetron in lieu of ondansetron. These patients had no documented nausea or vomiting requiring dose adjustments to the treatment plan or medical intervention. 40% of patients had results recommending avoidance of tamoxifen, 75% of which have ER+ breast cancer. 25% of patients had recommended changes to the dose of tamoxifen. Conclusions: Pharmacogenomic testing is feasible and available real-time for immediate use in the clinic. CYP mutations impact treatment decisions in a significant proportion of patients. Individualized treatment plans tailored to pharmacogenomic recommendations can be created in the multi-disciplinary setting and may decrease side effects of treatment and improve efficacy of curative therapy.

Clinical and social factors associated with excess weight in Hispanic and non-Hispanic White children

BACKGROUND

Hispanic children are disproportionately affected by obesity, with this disparity starting at a young age, and there is a paucity of data comparing factors associated with excess weight in the first year of life in Hispanic vs. non-Hispanic populations.

METHODS

Excess weight was defined as weight-for-length ≥95th percentile. The associations of potential risk factors were compared by ethnicity stratification.

RESULTS

Of the 1009 children, 302 (30.0%) were Hispanic and 707 (70.0%) were non-Hispanic White. The rate of excess weight was 30.1% and 13.6% among Hispanic and non-Hispanic White children, respectively. Factors associated with excess weight for non-Hispanic White children were higher than recommended weight gain during pregnancy (odds ratio (OR) 1.8 (1.2-3.1)), higher paternal body mass index (BMI) (OR 1.1 (1.02-1.15)), higher birth weight (OR 1.001 (1.001-1.002)), and lower breast milk feedings at 6 months (OR 0.98 (0.96-0.98)). Factors associated with excess weight for Hispanic children were lower maternal education (OR 2.37 (1.1-4.5)) and lower breast milk feedings at 6 months (OR 0.98 (0.96-0.99)).

CONCLUSION

There are differential risk factors associated with excess weight at 12 months between Hispanic and non-Hispanic White children. Identification of differential factors in different ethnicities may allow for more targeted anticipatory guidance reduce obesity in at-risk populations.

A phase I study of intravenous artesunate in patients with advanced solid tumor malignancies

PURPOSE

The artemisinin class of anti-malarial drugs has shown significant anti-cancer activity in pre-clinical models. Proposed anti-cancer mechanisms include DNA damage, inhibition of angiogenesis, TRAIL-mediated apoptosis, and inhibition of signaling pathways. We performed a phase I study to determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs) of intravenous artesunate (IV AS).

METHODS

Patients were enrolled in an accelerated titration dose escalation study with planned dose levels of 8, 12, 18, 25, 34 and 45 mg/kg given on days 1 and 8 of a 21-day cycle. Toxicities were assessed using the NCI CTCAE (ver. 4.0), and response was assessed using RECIST criteria (version 1.1). Pharmacokinetic (PK) studies were performed during cycle 1.

RESULTS

A total of 19 pts were enrolled, 18 of whom were evaluable for toxicity and 15 were evaluable for efficacy. DLTs were seen at dosages of 12 (1 of 6 patients), 18 (1 of 6) and 25 mg/kg (2 of 2), and were neutropenic fever (Gr 4), hypersensitivity reaction (Gr 3), liver function test abnormalities (Gr 3/4) along with neutropenic fever, and nausea/vomiting (Gr 3) despite supportive care. The MTD was determined to be 18 mg/kg. No responses were observed, while four patients had stable disease, including three with prolonged stable disease for 8, 10, and 11 cycles, for a disease control rate of 27%. PK parameters of AS and its active metabolite, dihydroartemisinin (DHA), correlated with dose.

CONCLUSION

The MTD of intravenous artesunate is 18 mg/kg on this schedule. Treatment was well tolerated. Modest clinical activity was seen in this pre-treated population. CLINICALTRIALS.

GOV IDENTIFIER

NCT02353026.

Tolerability of paclitaxel/carboplatin (PCb) in solid tumor patients (pts) infected with HIV

e14077

Background: Although cancer has long been a recognized hallmark of the HIV epidemic, the preservation of immunologic health with modern antiretroviral therapy (ART) and aging has resulted in a population increasingly susceptible to cancers not traditionally associated with advancing immunosuppression. Several of these cancers (including lung, anal and head & neck) are seen in excess compared to the background population. Defining tolerability of standard treatments and analyzing potential interactions between ART and chemotherapy provides evidence necessary to mitigate treatment disparities. Methods: We conducted a study to evaluate the tolerability of PCb in HIV+ cancer pts. AMC-078 (NCT01249443), originally designed as a phase I of vorinostat in combination with fixed doses of P (at 175mg/m2) and Cb (AUC 6) every 3 weeks, was amended to study pts treated with PCb alone after phase III testing in the background population was negative for the combination in lung cancer. Eligibility criteria: PS ≤ 2, advanced solid tumor and normal organ function, including CD4 count > 100 cells/mcL on stable ART. Up to 6 cycles of PCb were permitted. Clinically significant adverse events (AE) in prior cycles were managed by dose reductions. Results: 17 pts (10M/7F; median CD4, 389/mcL) were accrued, including lung (9) and anal (3) cancers; 8 pts had ritonavir (potent CYP inhibitor)-containing ART. 65 PCb cycles were administered to 16 evaluable pts, for a mean of 4+ cycles/pt; only 2 pts were treated with vorinostat. AE of special interest included ≥G3 (febrile) neutropenia and ≥ G2 neuropathy, below. 4 pts had partial responses (3 confirmed). Pharmacokinetic analyses (7 pts) are pending. Conclusions: PCb has similar toxicity profile in fit pts with HIV infection. No signal for worse myelosuppression or neuropathy was observed by ART regimen. Routine use of GCSF or empiric dose reduction for presumed risk is unjustified. Results support standard cancer treatment for this underserved population. Clinical trial information: NCT01249443. [Table: see text]

Early discussion of advance directives for patients with newly diagnosed cancer

91

Background: Although advance care planning and the completion of advance directives (ADs) are important methods to prevent unwanted aggressive care once patients have lost their decision-making capacity, only a minority of patients have ADs at the time of cancer diagnosis. Methods: We established a new multidisciplinary outpatient clinic to provide comprehensive care to patients with newly diagnosed cancer at the Inova Dwight and Martha Schar Cancer Institute in Northern Virginia. Improvement in advance care planning was chosen as one of the first quality improvement initiatives for 2015. We started the first PDSA cycle after creating the team, establishing the problem and goal statement, and reviewing the process map. We had three measures including: 1. Inquiring whether the patient has advance directives or not at the time of scheduling their first appointment, 2. Provide written information about advance directives at the patient’s first visit, 3. Obtain advance directives by the third office visit. The goal for each measure was 90%, 90%, and 50% by the end of 2015. Results: Between May-June 2015, 65 patients were evaluable. Baseline rates were 26%, 2%, and 12%, respectively for measures 1, 2, and 3. In July 2015, we convened a staff meeting to review each staff’s role in the process of advance care planning. The new patient schedulers had training and created a telephone script to effectively communicate advance directives information with patients. The front desk staff included written information about advance care planning in the new patient information folders. Clinical staff were asked to address any questions or concerns that patients have and to encourage patients to complete the ADs by next visit. After this intervention, the rates increased to 100%, 44%, and 33%, respectively for measures 1, 2, and 3 in August and September, 2015 (n = 45). Conclusions: Early discussion about the ADs for newly diagnosed cancer patients at our outpatient clinic showed improvement in the rate of completed ADs by a third office visit.

Reduction of paclitaxel neuropathy with cryotherapy

124

Background: Chemotherapy induced peripheral neuropathy (CIPN) is a common and potentially debilitating side effect of taxanes. Prior studies indicate weekly paclitaxel results in grade 2 or higher neuropathy in 25% of patients. Patients may experience persistent pain that impacts quality of life. Currently, there is little data that exists on effective therapies for prevention of paclitaxel neuropathy. This study investigates the efficacy and safety of cryotherapy for the prevention of paclitaxel-induced peripheral neuropathy. Methods: This is a single arm, phase II study of the effects of cryotherapy for breast cancer patients undergoing 12 cycles of weekly paclitaxel. Cryotherapy was administered by hypothermia mitts and slippers to patients’ hands and feet during, and 15 minutes before and after paclitaxel treatments. Neurologic assessments and neuropathy questionnaires were evaluated at baseline, every 4 cycles during treatment, and every 6 months follow up for two years. The primary objective is to assess if cryotherapy can decrease the rate of peripheral neuropathy. The primary efficacy endpoint is the rate of neuropathy in patients undergoing weekly paclitaxel treatments. Results: Between November 2014 and June 2015, 41 patients were enrolled in the study. Of 39 evaluable patients, 19 (48.7%) were without neurologic toxicity. 19 (48.7%) had grade 1 toxicity, paresthesia but without pain. Only one patient (2.6%) had grade 2 toxicity. Cryotherapy treatment was well tolerated; one patient could not participate due to cold intolerance. Conclusions: Cryotherapy reduced the incidence of pain and grade 2 or higher sensory neuropathy in patients receiving weekly paclitaxel. Clinical trial information: NCT02230319. [Table: see text]

Preclinical assessment of the interactions between the antiretroviral drugs, ritonavir and efavirenz, and the tyrosine kinase inhibitor erlotinib

PURPOSE

Prevalence of non-AIDS-defining cancers (NADCs) has increased in the era of potent antiretroviral treatments. Incidence rates of NADCs now exceed AIDS-defining cancers in HIV-positive patients. Treatment of NADCs may be complicated by interactions between antiretrovirals and chemotherapy mostly via inhibition or induction of CYP3A4. Erlotinib is used to treat non-small cell lung and pancreatic cancer and is primarily metabolized by CYP3A4 into multiple products including the active metabolite (OSI-420). Preclinical in vivo assessment was performed to gain a better understanding of CYP3A4-mediated interactions between antiretrovirals and erlotinib.

METHODS

Erlotinib (50 mg/kg p.o.) was administered to male FVB mice in the presence and absence of dexamethasone (10 mg/kg p.o. QDx4), efavirenz (25 mg/kg p.o. QDx4), ketoconazole (50 mg/kg p.o.), or ritonavir (12.5 mg/kg p.o.). Blood samples were collected to characterize exposure (AUC).

RESULTS

Administration of erlotinib with CYP3A4 inducers (dexamethasone) and inhibitors (ketoconazole and ritonavir) resulted in significant alterations in erlotinib exposure. Ketoconazole and ritonavir resulted in a 1.7- and 3.0-fold increase in erlotinib AUC, respectively, while dexamethasone results in a 0.6-fold decrease in erlotinib AUC. The CYP3A4 inducer efavirenz did not have a significant effect on erlotinib exposure.

CONCLUSION

CYP3A4 inducers and inhibitors altered the exposure of erlotinib. Until a definitive clinical trial is performed, erlotinib should be used with caution in patients on a ritonavir-containing antiretroviral regimen, while standard doses may be appropriate for patients on an efavirenz-containing antiretroviral regimen.

A phase 1 study of cetuximab and lapatinib in patients with advanced solid tumor malignancies

BACKGROUND

Acquired resistance to antiepidermal growth factor receptor (anti-EGFR) therapy may be caused by EGFR-v-erb-b2 avian erythroblastic leukemia viral oncogene homolog 2 (ErbB2) heterodimerization and pathway reactivation. In preclinical studies, inhibiting ErbB2 blocked this resistance mechanism and resensitized cells to anti-EGFR therapy. Cetuximab targets EGFR, whereas lapatinib inhibits both EGFR and ErbB2. The objective of this phase 1 trial was to assess the safety, dose-limiting toxicities (DLTs), and maximum tolerated doses (MTDs) of cetuximab and lapatinib in patients with solid tumors.

METHODS

Patients received standard weekly cetuximab with escalating lapatinib doses of 750 mg, 1000 mg, or 1250 mg daily in 3-week cycles. DLTs were monitored through the end of cycle 2. Pretreatment and post-treatment tumor biopsies and germline DNA samples were obtained for correlative studies.

RESULTS

Twenty-two patients were enrolled, and 18 patients each were evaluable for toxicity and response. Fifty-nine percent of patients had received prior anti-EGFR therapy. Common toxicities included rash and diarrhea. No patient experienced a DLT at the highest dose level, and no grade 4 toxicity was observed. Response included no complete responses, 3 partial responses, 9 patients with stable disease, and 6 patients with disease progression, for an overall response rate of 17% and a clinical benefit rate of 67%. The clinical benefit rate in patients who had previously received anti-EGFR therapy was 70%. The mean treatment duration was 4.7 cycles (range, 1-14 cycles). Decreased expression of EGFR/ErbB2 pathway components after treatment was correlated with response, whereas increased expression in the PI3K, Jak/Stat, and MAPK pathways occurred in nonresponders.

CONCLUSIONS

The combination of cetuximab and lapatinib was well tolerated, had the expected toxicities, and exhibited notable clinical activity, including in patients who had received previous anti-EGFR therapy. Further clinical study of this combination is warranted.

Combination antiretroviral therapy (cART) component ritonavir significantly alters docetaxel exposure

PURPOSE

Non-AIDS-defining cancers (NADCs) now exceed rates of AIDS-defining cancers in HIV-positive patients. Treatment of NADCs may be complicated by drug-drug interactions between antiretrovirals and chemotherapy. Docetaxel is a widely used anticancer agent that is primarily metabolized by CYP3A4 enzymes and used to treat NADCs. A preclinical in vivo assessment was performed to gain a better understanding of CYP3-mediated drug-drug interactions between antiretrovirals and docetaxel, as well as to assess any alterations in gene expression with these combinations.

METHODS

Docetaxel (20 mg/kg i.v.) was administered to male FVB mice in the presence and absence of dexamethasone (10 mg/kg p.o. ×4d), efavirenz (25 mg/kg p.o. ×4d), ketoconazole (50 mg/kg p.o.), or ritonavir (12.5 mg/kg p.o.). At various time points, plasma and liver tissue were harvested. Docetaxel concentrations were determined by LC/MS/MS. Pharmacokinetic parameters were calculated. Liver tissue RNA was used to evaluate alterations in Cyp3a11 and Abcb1a gene expression.

RESULTS

Docetaxel exposure was altered by CYP3A4 inhibitors but not by inducers. The CYP3A4 inducers efavirenz and dexamethasone did not have a significant effect on docetaxel exposure (AUC). However, the CYP3A4 inhibitors ritonavir and ketoconazole resulted in a 6.9- and 3.1-fold increase in AUC, respectively. Alterations in gene expression did not account for the altered docetaxel exposure.

CONCLUSIONS

Docetaxel exposure was significantly altered by CYP3A4 inhibitors. Until a definitive clinical trial is performed, docetaxel should be used with caution in patients on a ritonavir-containing antiretroviral regimen or an alternative antineoplastic therapy or antiretroviral regimen should be considered.

A phase 1/pharmacokinetic study of sunitinib in combination with highly active antiretroviral therapy in human immunodeficiency virus-positive patients with cancer: AIDS Malignancy Consortium trial AMC 061

BACKGROUND

The treatment of non-acquired immunodeficiency syndrome-defining cancers may be complicated by drug interactions between highly active antiretroviral therapy (HAART) and chemotherapy. This trial is the first by the AIDS Malignancy Consortium to assess targeted therapies and HAART in human immunodeficiency virus-positive patients (ClinicalTrials.gov identifier: NCT00890747).

METHODS

In a modified phase 1 study of sunitinib, patients were stratified into 2 treatment arms based on whether they were receiving therapy with ritonavir, a potent CYP3A4 inhibitor. Patients in treatment arm 1 (non-ritonavir HAART) received standard sunitinib dosing (50 mg/day). Treatment arm 2 (ritonavir-based HAART) used a phase 1, 3 + 3 dose escalation design (from 25 mg/day to 50 mg/day). Cycles were comprised of 4 weeks on treatment followed by a 2-week break (6 weeks total). The pharmacokinetics of sunitinib and its active metabolite (N-desethyl sunitinib) were assessed.

RESULTS

Nineteen patients were enrolled and were evaluable. Patients on treatment arm 1 tolerated treatment with no dose-limiting toxicity observed. In treatment arm 2, a dose-limiting toxicity was experienced at a dose of 37.5 mg, and an additional 3 of 5 patients experienced grade 3 neutropenia (toxicity graded as per National Cancer Institute Common Terminology Criteria for Adverse Events [version 4.0]), an uncommon toxicity of sunitinib. No patient achieved a response, but 10 patients had stable disease, including 8 with prolonged disease stability. Efavirenz, a potent inducer of CYP3A4, resulted in increased exposure of N-desethyl sunitinib, whereas ritonavir caused decreased exposure of the metabolite. Hand-foot syndrome was associated with higher steady-state trough concentrations of sunitinib.

CONCLUSIONS

Patients receiving non-ritonavir-based HAART regimens tolerated standard dosing of sunitinib. Patients receiving ritonavir-based therapy who were treated with a dose of 37.5 mg/day experienced higher toxicities. Dose reductions of sunitinib to 37.5 mg may be warranted in patients receiving ritonavir.

Final results of a phase I study of lapatinib (LAP) and cetuximab (CET) in patients with CET-sensitive solid tumors

2616

Background: Acquired resistance to anti-EGFR MoAb therapy may be via EGFR-ErbB2 heterodimerization and pathway reactivation. Dual anti-EGFR treatment was recently found to be active in colon cancer. We performed a phase I trial of CET and LAP to determine the DLTs, MTD, and clinical activity of the combination. Methods: Pts received CET at 400mg/m2 then 250 mg/m2 weekly, combined with daily LAP in a 3+3 dose escalation trial. LAP dose levels (DL) were (1) 750mg, (2) 1000mg, and (3) 1250mg. Cycles lasted 3 weeks, toxicity was assessed through C2, and pts were restaged every 2 cycles. Baseline and post-C1 tumor biopsies were analyzed for phosphoprotein activation in 36 EGFR/ErbB2 pathway proteins. Germ-line pharmacogenetic (PGx) variations were correlated with efficacy and toxicity. Results: Between 10/2010 and 10/2012, 22 pts were enrolled - colon (8), lung (8), head and neck (4), and anal cancers (2) - and 59% had prior anti-EGFR therapy. 18 pts were evaluable for toxicity, and 18 for response. Mean treatment was 3.8 cycles (range 1 - 12); 3 patients are still on trial. One DLT occurred at DL1 (gr 3 rash) and DL2 (gr 3 diarrhea). No pt on DL3 experienced a DLT. No pt experienced a gr 4 toxicity; gr 3 toxicities anytime on therapy included rash (17%), diarrhea (6%), fatigue (6%), lymphopenia (6%), and hypomagnesemia (6%). Rash was experienced by 94% of pts (gr 1=50%, gr 2=28%, and gr 3=17%). Partial responses (PR) occurred in 4 pts (22%), stable disease (SD) in 8 (44%), and disease progression in 6 (33%), for a clinical benefit rate of 67%. Seven of 13 (54%) pts on prior EGFR therapy had SD or PR. Down-regulation of phosphorylated EGFR/ErbB2 pathway components correlated with response; distinct pathway components were up-regulated in non-responders, including PI3K, Jak/Stat, MAPK, and IGF. PGx variants in FcRII correlated with response (p=0.045); no variants correlated with toxicity. Conclusions: The RP2D is CET 250 mg/m2 weekly and LAP 1250mg daily. Treatment was well tolerated with few grade 3 toxicities and a significant 67% clinical benefit rate. Non-responders showed up-regulation of EGFR pathway components – components which are druggable, warranting further study. A trial in colorectal cancer is ongoing. Clinical trial information: NCT01184482.

A phase I study of the BCR-ABL tyrosine kinase inhibitor nilotinib and cetuximab in patients with solid tumors that can be treated with cetuximab

TPS2624

Background: Therapeutic blockade of Epidermal Growth Factor Receptor (EGFR) signaling with the monoclonal antibody cetuximab is clinically effective in the treatment of patients with metastatic squamous cell carcinoma of the head and neck or KRAS wildtype colorectal cancer. However, these patients eventually become resistant to this therapy. An exploration of the EGFR signaling network using an EGFR network-focused small interfering RNA library identified potential regulators of resistance to EGFR-targeted therapies. The ABL1 gene was identified as a central node to target in this complex genomic pathway. In a preclinical EGFR-expressing cancer cell line model, targeting c-abl, the gene product of ABL1, using nilotinib was found to be highly synergistic in decreasing cell survival when combined with anti-EGFR targeted therapy. Methods: We have initiated an open-label Phase I study for patients who progressed after standard therapies for metastatic KRAS wildtype colorectal cancer or metastatic head and neck squamous cell carcinoma. Enrolled patients must have adequate performance status and organ function. Treatment consists of cetuximab 400 mg/m2 on day 1, then 250 mg/m2 once weekly, and nilotinib twice daily, starting on day 1, according to a traditional 3+3 dose escalation, from 200mg to 300mg BID. Patients are restaged every 2 cycles (every 8 weeks). The primary endpoint is the maximum tolerated dose (MTD) of nilotinib when used in conjunction with cetuximab. Secondary endpoints are clinical benefit rate (defined as rates of stable disease, partial response, and complete response) and response rate. Additionally, biopsies of metastases obtained prior to and after initiation of therapy will be used to establish primary tumor cell cultures using conditional cellular reprogramming to permit the dynamic study of signaling and drug sensitivity through an evaluation of evidence of a drug effect on EGFR signaling and on Antibody-Dependent Cell-Mediated Cytotoxicity. An additional 10 colorectal cancer patients will be treated as an expansion cohort at the MTD. This expansion cohort data may be used to plan a Phase II trial in the future.

A phase 1 study of efatutazone, an oral peroxisome proliferator-activated receptor gamma agonist, administered to patients with advanced malignancies

BACKGROUND

Efatutazone (CS-7017), a novel peroxisome proliferator-activated receptor gamma (PPARγ) agonist, exerts anticancer activity in preclinical models. The authors conducted a phase 1 study to determine the recommended phase 2 dose, safety, tolerability, and pharmacokinetics of efatutazone.

METHODS

Patients with advanced solid malignancies and no curative therapeutic options were enrolled to receive a given dose of efatutazone, administered orally (PO) twice daily for 6 weeks, in a 3 + 3 intercohort dose-escalation trial. After the third patient, patients with diabetes mellitus were excluded. Efatutazone dosing continued until disease progression or unacceptable toxicity, with measurement of efatutazone pharmacokinetics and plasma adiponectin levels.

RESULTS

Thirty-one patients received efatutazone at doses ranging from 0.10 to 1.15 mg PO twice daily. Dose escalation stopped when maximal impact on PPARγ-related biomarkers had been reached before any protocol-defined maximum-tolerated dose level. On the basis of a population pharmacokinetic/pharmacodynamic analysis, the recommended phase 2 dose was 0.5 mg PO twice daily. A majority of patients experienced peripheral edema (53.3%), often requiring diuretics. Three episodes of dose-limiting toxicities, related to fluid retention, were noted in the 0.10-, 0.25-, and 1.15-mg cohorts. Of 31 treated patients, 27 were evaluable for response. A sustained partial response (PR; 690 days on therapy) was observed in a patient with myxoid liposarcoma. Ten additional patients had stable disease (SD) for ≥60 days. Exposures were approximately dose proportional, and adiponectin levels increased after 4 weeks of treatment at all dose levels. Immunohistochemistry of archived specimens demonstrated that PPARγ and retinoid X receptor expression levels were significantly greater in patients with SD for ≥60 days or PR (P = .0079), suggesting a predictive biomarker.

CONCLUSIONS

Efatutazone demonstrates acceptable tolerability with evidence of disease control in patients with advanced malignancies.

Effect of distinct EGFR downstream pathways on resistance to dual EGFR/ErbB2 combined targeted therapy of lapatinib (LPT) and cetuximab (CTX)

91

Background: Resistance to EGFR therapy is poorly understood. We performed a phase I study in which pre- and post-treatment biopsies were profiled to assess the impact of CTX and LPT on downstream pathways that drive cancer progression. Methods: Between 10/2010 and 5/2012, 16 patients (pts) were enrolled in a 3+3 dose escalation trial, including: colon (7), lung (4), head and neck (3), and anal cancers (2). Prior EGFR therapy was allowed. CTX was 400mg/m2 on D1, then 250 mg/m2 weekly. LPT dose levels were 750 mg, 1000 mg, and 1250 mg daily. Cycles were 21 days in length; pts were assessed for response every 2 cycles. Pts underwent pre- and post-cycle 1 tumor biopsies. Biopsies were evaluated with a Reverse Phase MicroArray (RPMA) platform. Protein lysates were robotically immobilized in defined spots on nitrocellulose-coated slides; each printed array was then interrogated with a highly specific antibody. A total of 36 different proteins were analyzed, including total and phosphorylated EGFR, ErbB2, ErbB3, MET, IGF, MAPK, PI3K, Jak-Stat, and other subpathways. Relative baseline expression levels were determined, as were percent change in matched samples. Results: Of 12 pts evaluable for response, 2 had a partial response (PR), 5 had stable disease (SD), and 5 had disease progression (DP). Baseline tumor measurements of total ERK, p90RSK, and p38MAPK correlated with response (p<0.05), with a trend towards significance between response and expression of pEGFR, pMEK, pNFKB, and p4EBP1 (p<0.10). Nine patients had paired pre- and post-treatment biopsies. In tumors from pts with PR and SD, consistent down regulation of the EGFR pathway was detected. In the four patients with DP, up-regulation of distinct pathway components was detected, including of IGF (1 pt), Mek1/Erk (2 pts), mTOR (2 pts), and STAT3 (3 pts). Conclusions: A tumor profile was defined that correlated with clinical benefit to LPT+CTX. Resistance to this combination was due to upregulation of EGFR pathway components, components that are druggable. This analysis highlights the potential of personalizing therapy with combined EGFR therapies, and for adding additional targeted therapies to patients with resistant tumors.

The rising challenge of non-AIDS-defining cancers in HIV-infected patients

Since the advent of HAART, patients with HIV infection have seen a significant improvement in their morbidity, mortality, and life expectancy. The incidence of AIDS-defining illnesses, including AIDS-defining malignancies, has been on the decline. However, deaths due to non-AIDS-defining illnesses have been on the rise. These so-called non-AIDS-defining cancers (NADCs) include cancers of the lung, liver, kidney, anus, head and neck, and skin, as well as Hodgkin's lymphoma. It is poorly understood why this higher rate of NADCs is occurring. The key challenge facing oncologists is how to administer chemotherapy effectively and safely to patients on antiretroviral therapy. The challenge to clinicians caring for HIV-infected patients is to develop and implement effective means to screen, treat, and prevent NADCs in the future. This review presents data on the epidemiology and etiology of NADCs, as well as ongoing research into this evolving aspect of the HIV epidemic.

A phase I trial of the mTOR inhibitor temsirolimus (TEM) in combination with capecitabine (CAP) in patients with advanced malignancies

3095

Background: The mammalian target of rapamycin (mTOR) signaling pathway is critical for cell growth and proliferation. mTOR antagonists, such as TEM, have proven anti-cancer efficacy. Pre-clinical models and early phase clinical trials have demonstrated increased efficacy when an mTOR antagonist is combined with cytotoxic chemotherapy. Methods: Patients (pts) with advanced malignancies and adequate hepatic and renal function were eligible for enrollment. An alternating dose escalation of TEM and CAP was employed in separate q2week and q3week arms. Planned dose levels were: TEM 15 and 25mg IV weekly; and CAP 500, 750, 1000, and 1250 mg/m2 orally twice daily (BID). Restaging occurred every 4 cycles for the q2week arm, and every 3 cycles for the q3week arm. PK samples assessed serum levels of sirolimus at Day 0, 8, and 15 of the q2week arm. Archived tumor specimens were assayed by immunohistochemistry (IHC) for expression of phospho-AKT, phospo-4EBP1, phoshpo-p70S6, and PTEN. Results: Thirty-two pts were enrolled, 30 of whom were evaluable for toxicity, of which 18 were male, age range 30-72 years, 25 with colorectal cancer. Pts had received an average of 4 prior lines of therapy. The most common adverse events (AEs) were mucositis and fatigue. The most common grade 3/4 AEs were fatigue (n=4), diarrhea (n=2), and hypophosphatemia (n=2). In 16/30 pts, the dose of CAP was reduced. There were two DLTs, both hypophosphatemia in the q3week arm (TEM=25mg and CAP=1000mg/m2). For the q2week arm, the recommended phase II dose (RP2D) was TEM 25 mg + CAP 1000mg/m2. For the q3week arm, the RP2D was TEM 25mg + CAP 750mg/m2. Twenty-five pts were evaluable for response (18 for OS). There were no PRs or CRs, but 14/25 pts (56%) had SD, with 4/24 (16%) having prolonged SD of >6 months. Median TTP and OS were 3 and 7 months, respectively. Five pts are still on study. PK assessment of serum sirolimus levels, and the results of the IHC on archived tumor samples will be presented. Conclusions: The combination of TEM and CAP is safe on both a q2week and a q3week schedule. The combination demonstrated promising evidence of disease control in this highly refractory population and should be tested in disease-specific phase II trials.

A phase I study of lapatinib (LPT) and cetuximab (CTX) in patients with CTX-sensitive solid tumors

2590

Background: Preclinical research has shown that one mechanism of acquired resistance to CTX is via EGFR-ErbB2 heterodimerization, which can reactivate oncogenic pathways. LPT is a dual EGFR and ErbB2 intracellular tyrosine kinase inhibitor. A phase I translational clinical study was performed to determine the maximum tolerated dose (MTD), dose limiting toxicities (DLTs), and clinical activity of CTX and LPT in patients with EGFR-driven solid tumor malignancies that can be treated with CTX. Methods: Patients (Pts) were enrolled in a 3+3 dose escalation trial. Prior CTX therapy was allowed. CTX was given at 400mg/m2 on Cycle 1, Day 1 (C1D1), then 250 mg/m2 weekly. LPT dose levels (DL) were (1) 750mg, (2) 1000mg, and (3) 1250mg orally daily. Rash management included daily sunblock, steroid cream, and doxycycline. Cycle length was 21 days, and patients were assessed for toxicity through the end of C2, and for efficacy after every 2 cycles. Fresh tumor biopsies were obtained at baseline and at the end of C1 to compare EGFR and ErbB2 expression levels and EGFR related pathway activation. DNA from blood samples was analyzed for pharmacogenetic (PGx) variations and correlations with toxicity and pharmacokinetics (PK). Results: Between October, 2010 to January 2012, 13 pts were enrolled, with colon (4), lung (3), head and neck (3), and anal cancers (3); 10 were evaluable for toxicity. Treatment-related toxicities of any grade included: rash (67%), diarrhea (42%), fatigue (33%), nausea/vomiting (17%), and dehydration (8%). DLTs included G3 rash in 1 of 6 pts on DL1, and G3 diarrhea despite optimal therapy in 1 of 4 pts on DL2. Enrollment to DL2 continues. Of 7 pts evaluable for response, 1 had an uPR, 3 had SD, including 1 with SD of ≥4 cycles, and 3 had DP. Both patients with uPR and prolonged SD were treated on DL1. Tumor EGFR-ErbB2 and EGFR pathway phosphorylation analyses and PGx results will be presented. Conclusions: The combination of CTX and LPT is well tolerated with expected toxicities. Efficacy was seen even on DL 1. Phase II clinical studies in CTX-sensitive diseases such as colon and head and neck cancer are planned.

Quantitation of unbound sunitinib and its metabolite N-desethyl sunitinib (SU12662) in human plasma by equilibrium dialysis and liquid chromatography-tandem mass spectrometry: application to a pharmacokinetic study

A rapid, selective, and sensitive liquid chromatography-tandem mass spectrometry method was developed and validated for the simultaneous determination of unbound sunitinib and its active metabolite N-desethyl sunitinib in plasma. Plasma and post-dialysis buffer samples were extracted using a liquid-liquid extraction procedure with acetonitrile-n-butylchloride (1:4, v/v). Chromatographic separation was achieved on a Waters X-Terra® MS RP(18) column with a mobile phase consisting of acetonitrile and water (60:40, v/v) containing formic acid (0.1%, v/v) using an isocratic run, at a flow-rate of 0.2 mL/min. Analytes were detected by electrospray tandem mass spectrometry in the selective reaction monitoring mode. Linear calibration curves were generated over the ranges 0.1-100 and 0.02-5 ng/mL for sunitinib and 0.2-200 and 0.04-10 ng/mL for N-desethyl sunitinib in plasma and in phosphate-buffered solution, respectively. The values for both within-day and between-day precision and accuracy were well within the generally accepted criteria for analytical methods. The analytical range was sufficient to determine the unbound and total concentrations of both analytes. The method was applied for measurement unbound concentrations in addition to total concentrations of sunitinib and its metabolite in plasma of a cancer patient receiving 50 mg daily dose.

Phase I dose finding studies of obatoclax (GX15-070), a small molecule pan-BCL-2 family antagonist, in patients with advanced solid tumors or lymphoma

PURPOSE

Two phase I, single-agent studies were conducted to determine the dose and regimen of obatoclax, an antagonist of all BCL-2 antiapoptotic proteins, for evaluation in phase II trials. The two studies, GX001 and GX005, evaluated the safety and tolerability of weekly 1-hour and 3-hour infusions of obatoclax, respectively.

EXPERIMENTAL DESIGN

Eligible patients in both studies were adults with solid tumor or lymphoma and performance status 0-1 for whom standard therapies were not appropriate. In the GX001 study an accelerated dose titration design was initially used with subsequent cohorts of three to six patients with 40% dose increments between levels. In the GX005 study three to six patients entered at each dose level with 40% dose increments between levels.

RESULTS

Thirty-five patients were enrolled in studies GX001 (n = 8) and GX005 (n = 27). Clinically significant central nervous system (CNS) toxicity was observed using the 1-hour infusion schedule. The obatoclax maximum tolerated dose (MTD) in GX001 was 1.25 mg/m(2) due to these infusional CNS events. The 3-hour infusion schedule studied in GX005 had improved tolerability, and the obatoclax MTD was 20 mg/m(2). One patient in GX005 with relapsed non-Hodgkin's lymphoma achieved partial response of 2 months' duration, and one patient with relapsed non-Hodgkin's lymphoma had stable disease for 18 months.

CONCLUSIONS

The 1-hour infusion schedule of obatoclax was associated with neuropsychiatric dose-limiting toxicities at relatively low doses (MTD, 1.25 mg/m(2)). The 3-hour i.v. infusion of obatoclax administered once weekly to patients with solid tumors was better tolerated (MTD, 20 mg/m(2)), and evidence of clinical activity was observed.

A pharmacogenetic study of docetaxel and thalidomide in patients with castration-resistant prostate cancer using the DMET genotyping platform

The anticancer agent docetaxel shows significant inter-individual variation in its pharmacokinetic and toxicity profile. Thalidomide is an active anticancer agent and also shows wide pharmacological variation. Past pharmacogenetic research has not explained this variation. Patients with prostate cancer enrolled in a randomized phase II trial using docetaxel and thalidomide versus docetaxel alone were genotyped using the Affymetrix DMET 1.0 platform, which tests for 1256 genetic variations in 170 drug disposition genes. Genetic polymorphisms were analyzed for associations with clinical response and toxicity. In all, 10 single-nucleotide polymorphisms (SNPs) in three genes were potentially associated with response to therapy: peroxisome proliferator-activated receptor-delta (PPAR-delta), sulfotransferase family, cytosolic, 1C, member 2 (SULT1C2) and carbohydrate (chondroitin 6) sulfotransferase 3 (CHST3). In addition, 11 SNPs in eight genes were associated with toxicities to treatment: spastic paraplegia 7 (pure and complicated autosomal recessive) (SPG7), CHST3, cytochrome P450, family 2, subfamily D, polypeptide 6 (CYP2D6), N-acetyltransferase 2 (arylamine N-acetyltransferase) (NAT2), ATP-binding cassette, sub-family C (CFTR/MRP), member 6 (ABCC6), ATPase, Cu++ transporting, alpha polypeptide (ATP7A), cytochrome P450, family 4, subfamily B, polypeptide 1 (CYP4B1) and solute carrier family 10 (sodium/bile acid cotransporter family), member 2 (SLC10A2). Genotyping results between drug metabolizing enzymes and transporters (DMET) and direct sequencing showed >96% of concordance. These findings highlight the role that non-CYP450 metabolizing enzymes and transporters may have in the pharmacology of docetaxel and thalidomide.

Comparison of ATP-binding cassette transporter interactions with the tyrosine kinase inhibitors imatinib, nilotinib, and dasatinib

Although the development of tyrosine kinase inhibitors (TKIs) to control the unregulated activity of BCR-ABL revolutionized the therapy of chronic myeloid leukemia, resistance to TKIs is a clinical reality. Among the postulated mechanisms of resistance is the overexpression of ATP-binding cassette (ABC) transporters, such as P-glycoprotein (ABCB1) and breast cancer resistance protein (ABCG2), which mediate reduced intracellular drug accumulation. We compared the interactions of the TKIs imatinib, nilotinib, and dasatinib with ABCB1 and ABCG2 in ex vivo and in vitro systems. The TKIs inhibited rhodamine 123 and Hoechst 33342 efflux mediated by endogenous expression of the transporters in murine and human hematopoietic stem cells with potency order nilotinib >> imatinib >> dasatinib. Studies with ABCB1-, ABCG2-, and ABCC1-transfected human embryonic kidney 293 cells verified that nilotinib was the most potent inhibitor of ABCB1 and ABCG2. Cytotoxicity assays in stably transduced K562-ABCG2 and K562-ABCB1 cells confirmed that the TKIs were also substrates for the two transporters. Like imatinib, both nilotinib and dasatinib decreased ABCG2 surface expression in K562-ABCG2 cells. Finally, we found that all TKIs were able to compete labeling of ABCB1 and ABCG2 by the photo-cross-linkable prazosin analog [(125)I]iodoarylazidoprazosin, suggesting interaction at the prazosin-binding site of both proteins. Our experiments support the hypothesis that all three TKIs are substrates of ABC transporters and that, at higher concentrations, TKIs overcome transporter function. Taken together, the results suggest that therapeutic doses of imatinib and nilotinib may diminish the potential of ABCB1 and ABCG2 to limit oral absorption or confer resistance. Clinical data are required to definitively answer the latter question.

Clinical pharmacology and pharmacogenetics in a genomics era: the DMET platform

While no genome-wide pharmacogenetics study has yet been published, the field of pharmacogenetics is moving towards exploratory, large-scale analyses of the interaction between genetic variation and drug treatment. The Drug Metabolizing Enzymes and Transporters (DMET) platform offers a standardized set of 1936 variants in 225 genes related to drug absorption, distribution, metabolism and elimination that is useful to scan the genome for previously unknown associations between variation in absorption, distribution, metabolism and elimination genes and pharmacokinetic and pharmacodynamic outcomes of drug treatment. The purpose of this review is to put the DMET platform into context within the current study designs that have been used in pharmacogenetics, and to explore the role that DMET has played - and will play - in future pharmacogenetics studies.

Abstract A128: A phase I study of liposomal-encapsulated docetaxel (LE-DT) in patients with advanced solid tumor malignancies

Background: Docetaxel is a semi-synthetic microtubule disrupting antineoplastic drug indicated for the treatment of a wide variety of solid tumor malignancies. Past clinical trials have shown a dose-response correlation when used in the treatment of prostate and breast cancer. Common dose limiting toxicities are myelosuppression and neuropathy. Liposomes are versatile drug carriers that may increase drug solubility, serve as sustained release systems, provide protection from drug degradation and drug related toxicities, and help overcome multidrug resistance mediated by P-glycoprotein or similar resistant efflux mechanisms. The aims of this phase I study were to determine the maximum tolerated dose (MTD), dose limiting toxicities (DLTs), pharmacokinetics (pK), and clinical response of LE-DT in patients with advanced solid tumor malignancies.

Methods: LE-DT was administered using a standard 3+3 dose escalation schema with dose levels of 50, 65, 85, 110, and 132 mg/m2. Drug was infused over 1 hour. Premedication with dexamethasone was not required as it is with standard docetaxel therapy. In patients who experienced infusionrelated reactions pre-medication with steroids, antihistamines, and antipyretics were provided in subsequent cycles. Toxicities were recorded using NCI-CTCAE 3.0, and response was assessed using RECIST criteria. PK samples were drawn during C1 and analyzed using Win NonLin.

Results: Twenty-four patients were treated in total. The total number of cycles each patient received ranged from 1 to 21 (median = 4). Dose escalation proceeded until DLTs were experienced by 2 out of 2 patients at the 132mg/m2 dose level (both Grade 4 neutropenia). When additional patients were treated at the 110 mg/m2 dose, 2 patients experienced Grade 4 neutropenia. The dose level was reduced to 85mg/m2, with one patient experiencing Grade 4 neutropenia at this level. The protocol was amended to allow G-CSF growth factor support and dose re-escalation. An additional 4 patients were treated at 110mg/m2 and none of these patients experienced Grade 4 neutropenia. At this dose level, two patients experiencing Grade 3 fatigue. No patient experienced Grade 3/4 neuropathy, even in two patients treated for 10 and 21 cycles. Two patients experienced Grade 2 neuropathy. Additional toxicities included Grade 3 anemia in three patients. Drug pharmacokinetics followed a two-compartment elimination pattern. Cmax and AUCinf were proportional to dose through the 110mg/m2 dose level with a mean clearance of 28.5L/hr/m2. At the 132mg/m2 dose Cl was 45.4 L/hr/m2. Serum half-lives at the differing dose levels ranged from 15.1 to 22.4 hr. There was no correlation between pK measures and toxicity. One patient had a confirmed partial response (PR) and another had an unconfirmed PR (8%). Eight patients (33%) had prolonged stable disease lasting more than 3 months. One patient continues to have stable disease after 21 cycles.

Conclusion: LE-DT was tolerable with expected toxicities of neutropenia, anemia, and fatigue, but without water retention (edema). Importantly, in this heavily pretreated population no patient experienced clinically significant neuropathy. Clinical benefit (SD+PR) was observed in 41% of the patients. The recommended phase II dose of LE-DT is 110mg/m2 with growth factor support. Phase II studies of LE-DT in prostate and pancreatic cancers are planned.

Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A128.

Identification of compounds that correlate with ABCG2 transporter function in the National Cancer Institute Anticancer Drug Screen

ABCG2 is an ATP-binding cassette transporter that counts multiple anticancer compounds among its substrates and is believed to regulate oral bioavailability as well as serve a protective role in the blood-brain barrier, the maternal-fetal barrier, and hematopoietic stem cells. We sought to determine whether novel compounds that interact with the transporter could be identified through analysis of cytotoxicity profiles recorded in the NCI Anticancer Drug Screen database. A flow cytometric assay was used to measure ABCG2 function in the 60 cell lines and generate a molecular profile for COMPARE analysis. This strategy identified >70 compounds with Pearson correlation coefficients (PCCs) >0.4, where reduced drug sensitivity correlated with ABCG2 expression, as well as >120 compounds with PCCs < -0.4, indicating compounds to which ABCG2 expression conferred greater sensitivity. Despite identification of known single nucleotide polymorphisms in the ABCG2 gene in a number of the cell lines, omission of these lines from the COMPARE analysis did not affect PCCs. Available compounds were subjected to validation studies to confirm interaction with the transporter, including flow cytometry, [(125)I]IAAP binding, and cytotoxicity assays, and interaction was documented in 20 of the 27 compounds studied. Although known substrates of ABCG2 such as mitoxantrone or topotecan were not identified, we characterized three novel substrates-5-hydroxypicolinaldehyde thiosemicarbazone (NSC107392), (E)-N-(1-decylsulfanyl-3-hydroxypropan-2-yl)-3-(6-methyl-2,4-dioxo-1H-pyrimidin-5-yl)prop-2-enamide (NSC265473), and 1,2,3,4,7-pentahydroxy-1,3,4,4a,5,11b-hexahydro[1,3]dioxolo[4,5-j]phenanthridin-6(2H)-one [NSC349156 (pancratistatin)]-and four compounds that inhibited transporter function-2-[methyl(2-pyridin-2-ylethyl)-amino]fluoren-9-one hydroiodide (NSC24048), 5-amino-6-(7-amino-5,8-dihydro-6-methoxy-5,8-dioxo-2-quinolinyl)-4-(2-hydroxy-3,4-dimethoxyphenyl)-3-methyl-2-pyridinecarboxylic acid, methyl ester (NSC45384), (17beta)-2,4-dibromo-estra-1,3,5(10)-triene-3,17-diol (NSC103054), and methyl N-(pyridine-4-carbonylamino)carbamodithioate (NSC636795). In summary, COMPARE analysis of the NCI drug screen database using the ABCG2 functional profile was able to identify novel substrates and transporter-interacting compounds.

The 315-316 deletion determines the BXP-21 antibody epitope but has no effect on the function of wild type ABCG2 or the Q141K variant

ABCG2 is a half-transporter initially described in multidrug-resistant cancer cells and lately identified as an important factor in the pharmacokinetics of its substrates. Q141K is by far the most intensively studied single nucleotide polymorphism of ABCG2 with potential clinical relevance. Here we used stably transfected HEK cells to study the Q141K polymorphism together with the deletion of amino acids 315-316, which were recently reported to coexist in two cancer cell lines (A549 and SK-OV-3). Functional studies confirmed our previous report that when normalized to surface expression, Q141K has impaired transport of mitoxantrone. This result was extended to include the ABCG2-specific substrate pheophorbide a. While we found no functional consequence of deleting amino acids 315 and 316, we did find that the deletion mutant is no longer recognized by the BXP-21 antibody. We conclude that amino acids 315 and 316 form part of the epitope for the BXP-21 antibody.