Highly variable timing renders immunotherapy efficacy and toxicity impractical biomarkers of one another in clinical practice

Background

A useful clinical biomarker requires not only association but also a consistent temporal relationship. For instance, chemotherapy-induced neutropenia and epidermal growth-factor inhibitor-related acneiform rash both occur within weeks of treatment initiation, thereby providing information prior to efficacy assessment. Although immune checkpoint inhibitor (ICI)-associated immune-related adverse events (irAE) have been associated with therapeutic benefit, irAE may have delayed and highly variable onset. To determine whether ICI efficacy and irAE could serve as clinically useful biomarkers for predicting each other, we determined the temporal relationship between initial efficacy assessment and irAE onset in a diverse population treated with ICI.

Methods

Using two-sided Fisher exact and Cochran-Armitage tests, we determined the relative timing of initial efficacy assessment and irAE occurrence in a cohort of 155 ICI-treated patients (median age 68 years, 40% women).

Results

Initial efficacy assessment was performed a median of 50 days [interquartile range (IQR) 39-59 days] after ICI initiation; median time to any irAE was 77 days (IQR 28-145 days) after ICI initiation. Median time to first irAE was 42 days (IQR 20-88 days). Overall, 58% of any irAE and 47% of first irAE occurred after initial efficacy assessment. For clinically significant (grade ≥2) irAE, 60% of any and 53% of first occurred after initial efficacy assessment. The likelihood of any future irAE did not differ according to response (45% for complete or partial response vs. 47% for other cases; P=1). In landmark analyses controlling for clinical and toxicity follow-up, patients demonstrating greater tumor shrinkage at initial efficacy assessment were more likely to develop future grade ≥2 (P=0.05) and multi-organ (P=0.02) irAE.

Conclusions

In contrast to that seen with chemotherapy and molecularly targeted therapies, the temporal relationship between ICI efficacy and toxicity is complex and bidirectional. In practice, neither parameter can be routinely relied on as a clinical biomarker to predict the other.

pan-MHC and cross-Species Prediction of T Cell Receptor-Antigen Binding

Profiling the binding of T cell receptors (TCRs) of T cells to antigenic peptides presented by MHC proteins is one of the most important unsolved problems in modern immunology. Experimental methods to probe TCR-antigen interactions are slow, labor-intensive, costly, and yield moderate throughput. To address this problem, we developed pMTnet-omni, an Artificial Intelligence (AI) system based on hybrid protein sequence and structure information, to predict the pairing of TCRs of αβ T cells with peptide-MHC complexes (pMHCs). pMTnet-omni is capable of handling peptides presented by both class I and II pMHCs, and capable of handling both human and mouse TCR-pMHC pairs, through information sharing enabled this hybrid design. pMTnet-omni achieves a high overall Area Under the Curve of Receiver Operator Characteristics (AUROC) of 0.888, which surpasses competing tools by a large margin. We showed that pMTnet-omni can distinguish binding affinity of TCRs with similar sequences. Across a range of datasets from various biological contexts, pMTnet-omni characterized the longitudinal evolution and spatial heterogeneity of TCR-pMHC interactions and their functional impact. We successfully developed a biomarker based on pMTnet-omni for predicting immune-related adverse events of immune checkpoint inhibitor (ICI) treatment in a cohort of 57 ICI-treated patients. pMTnet-omni represents a major advance towards developing a clinically usable AI system for TCR-pMHC pairing prediction that can aid the design and implementation of TCR-based immunotherapeutics.

A phase II clinical trial evaluating the safety and efficacy of durvalumab as first line therapy in advanced and metastatic non-small cell lung cancer patients with Eastern Cooperative Oncology Group performance status of 2

Background

Approximately 30-40% of patients with advanced and metastatic non-small cell lung cancer (NSCLC) present with an impaired performance status (PS). There are limited prospective data on the safety and efficacy of durvalumab in these patients.

Methods

In this single-arm phase II clinical trial (NCT02879617), patients with previously untreated Stage IIIB/IV NSCLC and ECOG PS of 2 received durvalumab 1500 mg every 28 days until progression or unacceptable toxicity. The primary endpoints were overall survival (OS) and safety determined by grade ≥3 treatment-related adverse events (TRAEs).

Findings

Between April 2017 and March 2021, 50 patients were enrolled, of whom 47 received durvalumab. With a median follow-up of 28 months, median OS was 6 months (95% CI 4-10). TRAEs grade 3 occurred in nine of 47 patients (19%, 95% CI 9%-33%). OS in patients with a PD-L1 TPS of 0, 1-49%, and ≥50% was six months (95% CI 3-15), 11 months (95% CI 4-16), and 11 months (95% CI 0-not reached (NR)), respectively. Health related quality of life (HQRL) assessed at baseline and during therapy demonstrated no statistically significant change over the course of treatment.

Interpretation

This study demonstrates that single agent durvalumab is safe and well tolerated in the 1st line treatment of patients with advanced NSCLC and ECOG PS of 2, with an encouraging OS benefit in patients with PD-L1 positive tumors. This trial is amongst the largest prospective studies evaluating durvalumab in the 1st line treatment of advanced stage NSCLC and a PS of 2.

Funding

AstraZeneca, NCI P30CA047904.

Phase II Randomized Trial of Carboplatin, Pemetrexed, and Bevacizumab With and Without Atezolizumab in Stage IV Nonsquamous Non-Small-Cell Lung Cancer Patients Who Harbor a Sensitizing EGFR Mutation or Have Never Smoked

INTRODUCTION

Patients with non-small-cell lung cancer (NSCLC) who have never smoked or have tumors with mutations in EGFR generally derive minimal benefit from single-agent PD-1/PD-L1 checkpoint inhibitors. Prior data indicate that adding PD-L1 inhibition to anti-VEGF and cytotoxic chemotherapy may be a promising approach to overcoming immunotherapy resistance in these patients, however prospective validation is needed. This trial in progress (NCT03786692) is evaluating patients with stage IV NSCLC who have never smoked or who have tumors with sensitizing EGFR alterations to determine if a 4-drug combination of atezolizumab, carboplatin, pemetrexed, and bevacizumab can improve outcomes compared to carboplatin, pemetrexed and bevacizumab without atezolizumab.

METHODS

This is a randomized, phase II, multicenter study evaluating carboplatin, pemetrexed, bevacizumab with and without atezolizumab in 117 patients with stage IV nonsquamous NSCLC. Randomization is 2 to 1 favoring the atezolizumab containing arm. Eligible patients include: 1) those with tumors with sensitizing EGFR alterations in exons 19 or 21 or 2) patients who have never smoked and have wild-type tumors (ie, no EGFR, ALK or ROS1 alterations). Patients are defined as having never smoked if they have smoked less than 100 cigarettes in a lifetime. Patients with EGFR-mutated tumors must have disease progression or intolerance to prior tyrosine kinase inhibitor (TKI) therapy. The primary endpoint is progression-free survival (PFS). Secondary endpoints include overall survival (OS), response rate, duration of response, and time to response.

CONCLUSION

This phase II trial is accruing patients at U.S. sites through the National Comprehensive Cancer Network (NCCN). The trial opened in August 2019 and accrual is expected to be completed in the Fall of 2024.

Phase 1 trial of bemcentinib (BGB324), a first-in-class, selective AXL inhibitor, with docetaxel in patients with previously treated advanced non-small cell lung cancer

OBJECTIVES

AXL, a transmembrane receptor tyrosine kinase, is highly expressed and associated with poor prognosis in non-small cell lung cancer (NSCLC). Bemcentinib (BGB324), a selective orally bioavailable small molecule AXL inhibitor, synergizes with docetaxel in preclinical models. We performed a phase I trial of bemcentinib plus docetaxel in previously treated advanced NSCLC.

MATERIALS AND METHODS

Escalation of two dose levels of bemcentinib (200 mg load × 3 days then 100 mg daily, or 400 mg load × 3 days then 200 mg daily) in combination with docetaxel (60 or 75 mg/m² every 3 weeks) followed a 3+3 study design. Due to hematologic toxicity, prophylactic G-CSF was added. Bemcentinib monotherapy was administered for one week prior to docetaxel initiation to assess pharmacodynamic and pharmacokinetic effects alone and in combination. Plasma protein biomarker levels were measured.

RESULTS

21 patients were enrolled (median age 62 years, 67% male). Median treatment duration was 2.8 months (range 0.7-10.9 months). The main treatment-related adverse events were neutropenia (86%, 76% ≥G3), diarrhea (57%, 0% ≥G3), fatigue (57%, 5% ≥G3), and nausea (52%, 0% ≥G3). Neutropenic fever occurred in 8 (38%) patients. The maximum tolerated dose was docetaxel 60 mg/m² with prophylactic G-CSF support plus bemcentinib 400 mg load × 3 days followed by 200 mg daily thereafter. Bemcentinib and docetaxel pharmacokinetics resembled prior monotherapy data. Among 17 patients evaluable for radiographic response, 6 (35%) patients had partial response and 8 (47%) patients had stable disease as best response. Bemcentinib administration was associated with modulation of proteins involved in protein kinase B signaling, reactive oxygen species metabolism, and other processes.

CONCLUSION

Bemcentinib plus docetaxel with G-CSF support demonstrates anti-tumor activity in previously treated, advanced NSCLC. The role of AXL inhibition in the treatment of NSCLC remains under investigation.

Systemic immune parameters after prior radiation therapy in patients receiving immune checkpoint inhibitors

INTRODUCTION

Preclinical studies have demonstrated the ability of radiation therapy (RT) to augment immune response and tumor control by immune checkpoint inhibitors (ICI). However, numerous clinical trials combining RT and ICI have yielded relatively disappointing results. To improve understanding of optimal use of these therapies, we assessed systemic immune effects of prior RT in patients receiving ICI.

METHODS AND MATERIALS

Pre- and post-ICI blood samples were collected from patients enrolled in a prospective immunotherapy biospecimen protocol. Mutiplex panels of 40 cytokines and 120 autoantibodies (Ab) were analyzed. We identified differences in these parameters according to receipt, timing, and type of prior RT. We calculated P values using the Pearson product-moment correlation coefficient and false discovery rate (FDR) using the Benjamini-Hochberg Procedure.

RESULTS

Among 277 total patients, 69 (25%) received RT in the 6 months prior to ICI initiation. Among RT-treated patients, 23 (33%) received stereotactic RT, and 33 (48%) received curative intent RT. There was no significant difference in demographics or type of immunotherapy between patients according to prior RT exposure. Baseline complement C8 Ab and MIP-1d/CCL15 were significantly higher among patients with prior RT. For MIP-1d/CCL15, only prior stereotactic RT was associated with significant differences.

CONCLUSIONS

Prior RT is associated with few changes in systemic immune parameters in patients receiving ICI. The underlying mechanisms and optimal approach to harnessing the potential synergy of RT and ICI require further prospective clinical investigation.

Association between Antibiotic Exposure and Systemic Immune Parameters in Cancer Patients Receiving Checkpoint Inhibitor Therapy

Antibiotic administration is associated with worse clinical outcomes and changes to the gut microbiome in cancer patients receiving immune checkpoint inhibitors (ICI). However, the effects of antibiotics on systemic immune function are unknown. We, therefore, evaluated antibiotic exposure, therapeutic responses, and multiplex panels of 40 serum cytokines and 124 antibodies at baseline and six weeks after ICI initiation, with p < 0.05 and false discovery rate (FDR) < 0.2 considered significant. A total of 251 patients were included, of whom the 135 (54%) who received antibiotics had lower response rates and shorter survival. Patients who received antibiotics prior to ICI initiation had modestly but significantly lower baseline levels of nucleolin, MDA5, c-reactive protein, and liver cytosol antigen type 1 (LC1) antibodies, as well as higher levels of heparin sulfate and Matrigel antibodies. After ICI initiation, antibiotic-treated patients had significantly lower levels of MDA5, CENP.B, and nucleolin antibodies. Although there were no clear differences in cytokines in the overall cohort, in the lung cancer subset (53% of the study population), we observed differences in IFN-γ, IL-8, and macrophage inflammatory proteins. In ICI-treated patients, antibiotic exposure is associated with changes in certain antibodies and cytokines. Understanding the relationship between these factors may improve the clinical management of patients receiving ICI.

Itraconazole Exerts Its Antitumor Effect in Esophageal Cancer By Suppressing the HER2/AKT Signaling Pathway

Itraconazole, an FDA-approved antifungal, has antitumor activity against a variety of cancers. We sought to determine the effects of itraconazole on esophageal cancer and elucidate its mechanism of action. Itraconazole inhibited cell proliferation and induced G₁-phase cell-cycle arrest in esophageal squamous cell carcinoma and adenocarcinoma cell lines. Using an unbiased kinase array, we found that itraconazole downregulated protein kinase AKT phosphorylation in OE33 esophageal adenocarcinoma cells. Itraconazole also decreased phosphorylation of downstream ribosomal protein S6, transcriptional expression of the upstream receptor tyrosine kinase HER2, and phosphorylation of upstream PI3K in esophageal cancer cells. Lapatinib, a tyrosine kinase inhibitor that targets HER2, and siRNA-mediated knockdown of HER2 similarly suppressed cancer cell growth in vitro. Itraconazole significantly inhibited growth of OE33-derived flank xenografts in mice with detectable levels of itraconazole and its primary metabolite, hydroxyitraconazole, in esophagi and tumors. HER2 total protein and phosphorylation of AKT and S6 proteins were decreased in xenografts from itraconazole-treated mice compared to xenografts from placebo-treated mice. In an early phase I clinical trial (NCT02749513) in patients with esophageal cancer, itraconazole decreased HER2 total protein expression and phosphorylation of AKT and S6 proteins in tumors. These data demonstrate that itraconazole has potent antitumor properties in esophageal cancer, partially through blockade of HER2/AKT signaling.

Phase 1 study of ARQ 761, a β-lapachone analogue that promotes NQO1-mediated programmed cancer cell necrosis

BACKGROUND

NAD(P)H:quinone oxidoreductase 1 (NQO1) is a two-electron oxidoreductase expressed in multiple tumour types. ARQ 761 is a β-lapachone (β-lap) analogue that exploits the unique elevation of NQO1 found in solid tumours to cause tumour-specific cell death.

METHODS

We performed a 3+3 dose escalation study of 3 schedules (weekly, every other week, 2/3 weeks) of ARQ 761 in patients with refractory advanced solid tumours. Tumour tissue was analysed for NQO1 expression. After 20 patients were analysed, enrolment was restricted to patients with NQO1-high tumours (H-score ≥ 200).

RESULTS

A total of 42 patients were treated. Median number of prior lines of therapy was 4. Maximum tolerated dose was 390 mg/m² as a 2-h infusion every other week. Dose-limiting toxicity was anaemia. The most common treatment-related adverse events were anaemia (79%), fatigue (45%), hypoxia (33%), nausea (17%), and vomiting (17%). Transient grade 3 hypoxia, reflecting possible methemoglobinaemia, occurred in 26% of patients. Among 32 evaluable patients, best response was stable disease (n = 12); 6 patients had tumour shrinkage. There was a trend towards improved efficacy in NQO1-high tumours (P = 0.06).

CONCLUSIONS

ARQ 761 has modest single-agent activity, which appears associated with tumour NQO1 expression. Principal toxicities include anaemia and possible methemoglobinaemia.

Consolidative Radiotherapy for Limited Metastatic Non-Small-Cell Lung Cancer: A Phase 2 Randomized Clinical Trial

Importance

Patterns-of-failure studies suggest that in metastatic non-small-cell lung cancer (NSCLC) sites of gross disease at presentation are the first to progress when treated with chemotherapy. This knowledge has led to increased adoption of local ablative radiation therapy in patients with stage IV NSCLC, though prospective randomized evidence is limited.

Objective

To determine if intervening with noninvasive stereotactic ablative radiotherapy (SAbR) prior to maintenance chemotherapy in patients with non-progressive limited metastatic NSCLC after induction therapy led to significant improvements in progression-free survival (PFS).

Design, Setting, and Participants

This is a single-institution randomized phase 2 study of maintenance chemotherapy alone vs SAbR followed by maintenance chemotherapy for patients with limited metastatic NSCLC (primary plus up to 5 metastatic sites) whose tumors did not possess EGFR-targetable or ALK-targetable mutations but did achieve a partial response or stable disease after induction chemotherapy.

Interventions

Maintenance chemotherapy or SAbR to all sites of gross disease (including SAbR or hypofractionated radiation to the primary) followed by maintenance chemotherapy.

Main Outcomes and Measures

The primary end point was PFS; secondary end points included toxic effects, local and distant tumor control, patterns of failure, and overall survival.

Results

A total of 29 patients (9 women and 20 men) were enrolled; 14 patients (median [range] age, 63.5 [51.0-78.0] years) were allocated to the SAbR-plus-maintenance chemotherapy arm, and 15 patients (median [range] age, 70.0 [51.0-79.0] years) were allocated to the maintenance chemotherapy-alone arm. The trial was stopped to accrual early after an interim analysis found a significant improvement in PFS in the SAbR-plus-maintenance chemotherapy arm of 9.7 months vs 3.5 months in the maintenance chemotherapy-alone arm (P = .01). Toxic effects were similar in both arms. There were no in-field failures with fewer overall recurrences in the SAbR arm while those patients receiving maintenance therapy alone had progression at existing sites of disease and distantly.

Conclusions and Relevance

Consolidative SAbR prior to maintenance chemotherapy appeared beneficial, nearly tripling PFS in patients with limited metastatic NSCLC compared with maintenance chemotherapy alone, with no difference in toxic effects. The irradiation prevented local failures in original disease, the most likely sites of first recurrence. Furthermore, PFS for patients with limited metastatic disease appeared similar to those patients with a greater metastatic burden, further arguing for the potential benefits of local therapy in limited metastatic settings.

Trial Registration

clinicaltrials.gov Identifier: NCT02045446.

Spotlight on bevacizumab and its potential in the treatment of malignant pleural mesothelioma: the evidence to date

Malignant pleural mesothelioma (MPM) is a rare, but aggressive cancer. Surgery and radiation offer limited benefit, and systemic chemotherapy remains the primary treatment modality for the majority of patients. Vascular endothelial growth factor (VEGF) and its receptor have been recognized as important players in the biology of this disease. Bevacizumab is a monoclonal antibody that binds VEGF and blocks its interaction with the VEGF receptor. Recent studies have shown benefit with the addition of bevacizumab to the combination of cisplatin and pemetrexed in MPM. This combination is now included in the National Comprehensive Cancer Network guidelines (with a category 2A recommendation) as a possible first-line treatment for unresectable MPM in appropriately selected patients. This review discusses the rationale behind the use of bevacizumab in MPM, as well as summarizes the pharmacology, efficacy, safety, and toxicity of bevacizumab across multiple trials. The use of small-molecule inhibitors of angiogenesis in the treatment of MPM is also discussed.

Modern management of malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a deadly disease that produces a significant worldwide health care burden. The majority of cases are associated with prior asbestos exposure, but recent studies have identified a possible genetic predisposition in a minority of patients. Historically, obtaining a pathologic diagnosis of MPM was challenging, but with current pathological techniques, a secure diagnosis is possible in the majority of patients. Curative therapy for MPM remains elusive, and the primary treatment option for fit patients is platinum-based chemotherapy. Encouraging recent reports suggest that there may be a benefit to the addition of bevacizumab to standard chemotherapy as well as with the use of immune checkpoint inhibitors in MPM. Selected patients may be considered for aggressive surgical approaches, but there is considerable controversy regarding the true benefit of surgery and multimodality therapy in this disease.

Randomized phase 2 trial of erlotinib in combination with high-dose celecoxib or placebo in patients with advanced non-small cell lung cancer

BACKGROUND

Cyclooxygenase 2 (COX-2)-dependent signaling represents a potential mechanism of resistance to therapy with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors. This is mediated in part through an EGFR-independent activation of mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (Erk) by prostaglandin E2 (PGE2). PGE2 promotes downregulation of E cadherin and epithelial to mesenchymal transition. The current study investigated EGFR and COX-2 inhibition in patients with non-small cell lung cancer (NSCLC) and elevated baseline urinary metabolite of PGE2 (PGEM).

METHODS

Patients with stage IIIB/IV (AJCC 6th edition) NSCLC who progressed after at least 1 line of therapy or refused standard chemotherapy were randomized to receive erlotinib and celecoxib versus erlotinib and placebo. The primary endpoint was progression-free survival (PFS) with 80% power to detect a 50% improvement with a 1-sided significance level of .2 in the intent-to-treat and elevated baseline PGEM populations. Secondary endpoints included response rate, overall survival, and evaluation of molecular markers to assess targeting COX-2-related pathways and evaluate EGFR tyrosine kinase inhibitor resistance.

RESULTS

A total of 107 patients were enrolled with comparable baseline characteristics. Among the patients treated with celecoxib, those with wild-type EGFR were found to have an increased PFS (3.2 months vs 1.8 months; P = .03). PFS was numerically improved among patients in the intent-to-treat group who received erlotinib and celecoxib compared with those treated with erlotinib and placebo (5.4 months vs 3.5 months; P = .33) and was increased in patients in the erlotinib and celecoxib arm with elevated baseline PGEM (5.4 months vs 2.2 months; P = .15). Adverse events were similar in both treatment arms.

CONCLUSIONS

The combination of erlotinib and celecoxib did not appear to improve outcomes in an unselected population, but selection by elevated baseline PGEM led to an increase in PFS with this combination. Patients with EGFR wild-type status may benefit from the combination of erlotinib and celecoxib.

Phase I dose escalation trial of nitroglycerin in addition to 5-fluorouracil and radiation therapy for neoadjuvant treatment of operable rectal cancer

BACKGROUND

Nitric oxide donors decreased cell survival in vitro and tumor load in vivo in models of rectal cancer subjected to ionizing radiation. Nitroglycerin (NTG) transdermal patches, added to chemotherapy, have been shown to improve outcomes in lung cancer patients.

METHODS

This open-label, nonrandomized, multicohort, dose escalation, phase I trial had a primary endpoint to evaluate the safety, tolerability, feasibility, dose-limiting toxicity and maximum tolerated dose of topical NTG in addition to 5-fluorouracil and radiation therapy for neoadjuvant treatment of locoregionally advanced operable rectal cancer. The secondary endpoint was rate of pathologic complete response (pCR). Patients were assigned to 3 sequential cohorts of escalating dose levels of commercially available NTG patches (0.2, 0.4, and 0.6 mg/h), each cohort was intended to consist of 3 patients.

RESULTS

Thirteen patients were enrolled in the trial as specified in the dose escalation protocol. They were all male with a median age of 59.4 ± 2.5 (SEM) years. The observed toxicities were mild to moderate and manageable. Four patients developed asymptomatic grade 3 lymphopenia during the chemoradiation that resolved promptly upon completion. One patient had a non-ST segment elevation MI and 1 patient developed diarrhea. None of these toxicities were attributed to NTG except for 1 patient who developed a grade 3 headache. This required an additional group of patients at the same dose and no other patient experienced headaches. pCR was 17%.

CONCLUSION

NTG patches are well-tolerated and it is feasible to proceed with a phase II trial at the maximum dose examined (0.6 mg/h).

Upper extremity venous thrombosis in patients with cancer with peripherally inserted central venous catheters: a retrospective analysis of risk factors

PURPOSE

Peripherally inserted central catheters (PICCs) are often used in place of mediport catheters because of cost and lack of operating room time and to prevent delays in therapy. One common complication associated with their use is upper extremity venous thrombosis (UEVT). The purpose of this study was to ascertain risk factors associated with an increased risk of PICC-associated UEVT in patients with cancer.

METHODS

Retrospective analysis identified 237 patients with cancer who received PICCs at the Dallas Veterans Affairs Medical Center from 2006 to 2009. We analyzed many risk factors, including PICC infection (PI), use of erythropoiesis-stimulating agents (ESAs), antiplatelet agents (APAs), treatment dose anticoagulation (TDA), and bevacizumab.

RESULTS

Of 237 patients, 36 (15%) were found to have UEVT. Stepwise logistic regression analysis showed risk factors positively associated with UEVT were use of ESAs (odds ratio [OR], 10.66; 95% CI, 2.25 to 50.49), hospitalization (OR, 2.38; 95% CI, 1.05 to 5.39), PI (OR, 2.46; 95% CI, 1.03 to 5.86), and TDA (OR, 8.34; 95% CI, 2.98 to 23.33), whereas patients receiving APAs had a lower risk of UEVT (OR, 0.25; 95% CI, 0.07 to 0.92).

CONCLUSION

Specific factors significantly increase the risk of UEVT in patients with cancer with PICCs, whereas use of APAs seems to have a protective effect against UEVT. These results may aid in the development of a predictive model for identifying patients at high risk of UEVT who may benefit from APAs, as well as in determining preventive strategies for reducing the risk of PICC-associated UEVT.

Shorter bevacizumab infusions do not increase the incidence of proteinuria and hypertension

BACKGROUND

A previous study has shown that shorter bevacizumab infusions (0.5 mg/kg/min) can be safely administered without increasing the risk of infusion-related hypersensitivity reactions (HSRs). However, the risk of proteinuria and hypertension in patients receiving shorter infusions of bevacizumab is undetermined.

PATIENTS AND METHODS

This was a multicenter, prospective, observational study in patients receiving <10 mg/kg of bevacizumab infused over 0.5 mg/kg/min. Patients were observed until discontinuation of bevacizumab for progression of cancer or toxicity. The incidence of hypertension and proteinuria was compared with a prior cohort of patients who had received standard duration infusions of bevacizumab.

RESULTS

Sixty-three patients received a total of 392 doses of shorter bevacizumab infusions. Nineteen (30.2%) patients experienced proteinuria while receiving bevacizumab. Out of 19 patients, 13 had grade 1 and 6 had grade 2 proteinuria. None of the patients experienced grade 3 or 4 proteinuria. Hypertension was reported in 32 (50.8%) patients receiving bevacizumab. Twelve (19%) patients developed grade 3 or greater hypertension on bevacizumab. The incidence of proteinuria and hypertension was 38.3% and 56.6%, respectively, in patients (N = 120, 1347 infusions) receiving standard duration infusions of bevacizumab.

CONCLUSIONS

Shorter bevacizumab infusions (0.5 mg/kg/min) do not increase the risk of proteinuria and hypertension.

Consent timing and experience: modifiable factors that may influence interest in clinical research

PURPOSE

Low rates of participation in cancer clinical trials have been attributed to patient, institutional, and study characteristics. However, few studies have examined factors related to the consent process. We therefore evaluated the impact of consent timing and experience on markers of patient interest in research.

METHODS

We performed a retrospective analysis of patients enrolled in a cancer center tissue repository. During enrollment, patients were asked if they were willing to be contacted in the future to provide medical follow-up information and/or to participate in other clinical research. We analyzed the association between patient responses to these questions and consent process factors using univariate analysis and multivariate logistic regression.

RESULTS

Of 922 patients evaluated, 85% agreed to be contacted to provide follow-up information, and 83% agreed to be contacted to participate in future research studies. In univariate analysis, willingness to be contacted for future research was associated with consenter experience (P = .01) and had a trend toward association with the timing of enrollment in relation to diagnosis (P = .08), but it was not associated with patient sex, race, or diagnosis. In multivariate analysis, responses remained associated with consenter experience (P = .02).

CONCLUSION

Factors related to the consent process, including consenter experience and timing of study enrollment, are significantly associated with or have a trend toward association with markers of patient interest in clinical research. These understudied and potentially modifiable variables warrant further evaluation.

ERCC1 expression and outcomes in head and neck cancer treated with concurrent cisplatin and radiation

BACKGROUND

Overexpression of excision repair cross complementing group 1 (ERCC1), a DNA repair enzyme, is associated with resistance to cisplatin.

MATERIALS AND METHODS

Tissues from 73 patients with squamous cell carcinoma of the head and neck (HNSCC) who received concurrent cisplatin and radiation was analyzed immunohistochemically to determine if ERCC1 expression predicted for survival and response. Expression was scored as follows: 0=0% tumor nuclei positive, 1+=<50%, 2+=50-75% and 3+=>75%.

RESULTS

ERCC1 expression was 0 in 0%, 1+ (14%), 2+ (42%) and 3+ (44%). In uni- and multivariate analyses, 3+ ERCC1 expression was not a significant predictor of survival or response. Median survival for the ERCC1 3+ patients was 2.9 years versus 2.1 years for the ERCC1 <3+ group (p=0.44).

CONCLUSION

In this retrospective review of HNSCC patients receiving concurrent cisplatin and radiation, ERCC1 expression was not a significant predictor of survival or response.

Incidence of Isolated Heparin-Induced Thrombocytopenia and Risk of Thrombosis by IgG-Specific Anti-PF4/Heparin ELISA

Heparin-induced thrombocytopenia (HIT) antibodies are screened by an enzyme-linked immunosorbent assay (ELISA). Polyspecific ELISA detects anti-PF4/heparin IgG, IgA, and IgM. Recently, anti-PF4/heparin IgG ELISA has been shown to be more specific. However, the impact of using the IgG-ELISA on the incidence of isolated HIT (thrombocytopenia alone without clinically evident thrombosis) and the risk of developing subsequent thrombosis are still unknown. Methods: A total of 492 consecutive patients with clinically suspected HIT at The University of Texas Southwestern Medical Center and affiliated hospitals were retrospectively reviewed from December 2008 to May 2010. RESULTS: 29 patients (6%) were diagnosed with HIT based on clinical findings and positive ELISA. 19 of the 29 patients (65%) had thrombosis at the time of diagnosis; whereas 10 of the 29 (35%) had only isolated HIT. The ten patients with isolated HIT had serial follow up for at least 3 months. 3 of 10 were treated with direct thrombin inhibitors and 5 of 10 were treated with Warfarin for at least 1 month upon discharge. None of them developed symptoms or signs of thrombosis during 3 months of follow up. Conclusion: The incidence of isolated HIT in this study was 35%, which is significantly lower than previously reported in the literature. It is possible that some patients previously thought to have HIT by the poly-specific ELISA assay had false positive results. The improved specificity of the IgG- ELISA appears to reduce the incidence of isolated HIT which may have lower risk of subsequent thrombosis.

Looking beyond surveillance, epidemiology, and end results: patterns of chemotherapy administration for advanced non-small cell lung cancer in a contemporary, diverse population

INTRODUCTION

Chemotherapy prolongs survival without substantially impairing quality of life for medically fit patients with advanced non-small cell lung cancer (NSCLC), but population-based studies have shown that only 20 to 30% of these patients receive chemotherapy. These earlier studies have relied on Medicare-linked Surveillance, Epidemiology, and End Results (SEER) data, thus excluding the 30 to 35% of lung cancer patients younger than 65 years. Therefore, we determined the use of chemotherapy in a contemporary, diverse NSCLC population encompassing all patient ages.

METHODS

We performed a retrospective analysis of patients diagnosed with stage IV NSCLC from 2000 to 2007 at the University of Texas Southwestern Medical Center. Demographic, treatment, and outcome data were obtained from hospital tumor registries. The association between these variables was assessed using univariate analysis and multivariate logistic regression.

RESULTS

In all, 718 patients met criteria for analysis. Mean age was 60 years, 58% were men, and 45% were white. Three hundred fifty-three patients (49%) received chemotherapy. In univariate analysis, receipt of chemotherapy was associated with age (53% of patients younger than 65 years versus 41% of patients aged 65 years and older; p = 0.003) and insurance type (p < 0.001). In a multivariate model, age and insurance type remained associated with receipt of chemotherapy. For individuals receiving chemotherapy, median survival was 9.2 months, compared with 2.3 months for untreated patients (p < 0.001).

CONCLUSIONS

In a contemporary population representing the full age range of patients with advanced NSCLC, chemotherapy was administered to approximately half of all patients-more than twice the rate reported in some earlier studies. Patient age and insurance type are associated with receipt of chemotherapy.

Retrospective analysis of the consequences of acid suppressive therapy on ketoconazole efficacy in advanced castration-resistant prostate cancer

BACKGROUND

The area under the curve of a single ketoconazole dose has been shown to decrease significantly when administered with acid suppressive therapy. No published studies have examined the clinical impact of concurrent ketoconazole and acid suppressive therapy in patients with castration-resistant prostate cancer (CRPC).

OBJECTIVE

To evaluate the effect of acid suppressive therapy on prostate-specific antigen (PSA) response rate in CRPC patients receiving ketoconazole.

METHODS

This retrospective study evaluated CRPC patients treated with ketoconazole 3 times daily between January 1, 1999, and September 30, 2009. Patients included in the analysis had failed androgen deprivation therapy, and were subsequently initiated on ketoconazole. Response (PSA decline ≥50% maintained ≥4 weeks) was evaluated in patients receiving ketoconazole with (group 1 [G1]) or without (group 2 [G2]) concurrent acid suppressive therapy.

RESULTS

Thirty patients (G1: 11 patients; G2: 19 patients) were included in the analysis. Mean age in G1 and G2 was 71.8 and 69.6 years, respectively. Most patients had received prior therapy with an antiandrogen (90.9% G1; 100% G2) and fewer patients received antiandrogen withdrawal therapy (27.3% G1; 21.1% G2). Median baseline PSA was 109.4 (G1) and 86.9 ng/mL (G2) (p = 0.55). Median duration of ketoconazole was 7.2 months in G1 and 5.8 months in G2 (p = 0.09). Ketoconazole adherence was 82% (G1) and 100% (G2). Median duration of concurrent acid suppressive therapy was 3.8 months (range 2.0-20.4) in G1. PSA response (72.7% and 47.4%; p = 0.26) and time to PSA response (1.2 vs 0.9 mo; p = 0.53) were statistically similar between G1 and G2, respectively. Median progression free survival was higher in G1 (11.5 vs 6.9 months in G2; p = 0.047).

CONCLUSIONS

Use of concurrent acid suppressive therapy and ketoconazole in CRPC patients did not decrease PSA response rate, and progression free survival was unexpectedly higher compared with the non-acid suppressive therapy group. Larger studies are needed to verify the clinical impact of acid suppressive therapy in combination with ketoconazole.

The impact of consenter characteristics and experience on patient interest in clinical research

BACKGROUND

To explain the historically low rates of participation in cancer clinical trials, several factors have been studied. These include subject characteristics and attitudes, clinical trial availability and eligibility criteria, and physician attitudes and communication skills. However, the impact of nonphysician research personnel, who often consent patients for studies, is unclear. We therefore evaluated the association between consenter characteristics and subject interest in clinical research.

METHODS

We performed a retrospective review of subjects enrolled in a university-based cancer center tissue repository. During enrollment, subjects were asked if they were willing to be contacted in the future to (a) provide medical follow-up information and (b) participate in other clinical research. We analyzed the association between responses to these questions and consenter characteristics using univariate analysis and multivariate logistic regression.

RESULTS

In total, 181 consenters enrolled 922 subjects. The majority of subjects agreed to be contacted for follow-up (84.9%) and future research (83.1%). Subject willingness to be contacted for future research was associated with greater consenter experience in univariate and multivariate analyses. In multivariate analysis, subject willingness to be contacted for future research was associated with discordance between subject and consenter gender, but not with subject gender, race, or income, or consenter gender or race.

CONCLUSIONS

Consenter experience and subject-consenter gender discordance were associated with greater subject interest in participating in future research. The role of consenters in clinical research merits future study and should be considered in efforts to increase cancer clinical trial accrual.

A Comparison of the Pharmacokinetics and Pharmacodynamics of Docetaxel between African-American and Caucasian Cancer Patients: CALGB 9871

PURPOSE

Increased clearance of drugs, such as oral cyclosporine, that are CYP3A and/or ABCB1 (P-gp/MDR1) substrates was reported in African-American compared with Caucasian patients. We hypothesized that the pharmacokinetics and pharmacodynamics of docetaxel, an i.v. administered cytotoxic and substrate for CYP3A4, CYP3A5, and ABCB1, would differ between African-American and Caucasian patients.

EXPERIMENTAL DESIGN

We investigated population pharmacokinetics and pharmacodynamics and the pharmacogenetics of CYP3A4, CYP3A5, and ABCB1 in African-American and Caucasian cancer patients who received docetaxel 75 or 100 mg/m(2) as a 1-h i.v. infusion. Plasma docetaxel concentrations were measured by high-performance liquid chromatography. Clinical toxicity and absolute neutrophil count (ANC) were monitored on days 8, 15, and 22 postadministration of docetaxel. Using a limited sampling strategy and nonlinear mixed-effects modeling, each patient's docetaxel clearance was estimated. Genotyping for known polymorphisms in CYP3A4, CYP3A5, and ABCB1 was done.

RESULTS

We enrolled 109 patients: 40 African-Americans (26 males; 14 females), with a median age of 61 years (range, 29-73), and 69 Caucasians (43 males; 26 females), with a median age of 63 years (range, 38-81). There was no difference in the geometric mean docetaxel clearance between African-American patients [40.3 L/h; 95% confidence interval (95% CI), 19.3-84.1] and Caucasian patients (41.8 L/h; 95% CI, 22.0-79.7; P = 0.6). We observed no difference between African-American and Caucasian patients in the percentage decrease in ANC nor were docetaxel pharmacokinetic parameters related to the genotypes studied.

CONCLUSIONS

Docetaxel clearance and its associated myelosuppression were similar in African-American and Caucasian cancer patients.

Epidermal growth factor receptor mutations in non-small cell lung cancer: a basic science discovery with immediate clinical impact

A large body of preclinical work suggested that the epidermal growth factor receptor (EGFR) would be a successful target for therapy against non-small cell lung cancer (NSCLC), and this led to the development of oral, selective EGFR tyrosine kinase inhibitors (TKI) that improve symptoms and survival in patients with advanced NSCLC. However, not all patients benefit from this treatment, and there has been great interest in identifying the molecular correlates that predict for response to these agents. The recent detection of somatic mutations in EGFR that predict for response to the EGFR tyrosine kinase inhibitors has excited the scientific community. This discovery has far-reaching implications, not only for lung cancer patients treated with an EGFR TKI but also for future drug development in all malignancies.

Antiangiogenic therapies for mesothelioma

A large body of preclinical evidence suggests that angiogenesis plays a key role in the pathogenesis of malignant mesothelioma. Several mediators of angiogenesis seem to be autocrine growth factors in mesothelioma, and in preclinical models, agents that target angiogenesis produce tumor regression. Several clinical trials are currently evaluating the efficacy of inhibitors of angiogenesis in mesothelioma. This article details the preliminary results of these trials and future directions.

A randomized trial assessing the utility of a test-dose program with taxanes

OBJECTIVE

Taxanes are commonly used anticancer agents with a potential of producing an allergic or hypersensitivity reaction (HSR). We performed a randomized study to evaluate the value of a test dose given prior to the full dose of either paclitaxel or docetaxel.

RESEARCH DESIGN AND METHODS

Patients were randomly assigned to either the administration of the full dose or to the prior administration of a 1 mg intravenous test dose of either paclitaxel or docetaxel. The primary endpoints were severity of the HSR and the cost of drug wastage due to a HSR.

RESULTS

Two hundred and eighteen patients were randomized from three different treatment sites. The overall incidence of HSR was 6.5% and there was no significant difference in the incidence of HSR in either group. The mean HSR severity grade was 2.8 for patients without a test dose and 2.3 for those receiving a test dose. There was, however, a reduction in the wastage of taxane in the test dose arm. Wastage avoided in the test dose arm was $1573 per patient who had a HSR and $104 per patient treated with a taxane.

CONCLUSION

Although a test dose may not reduce the severity of a HSR with the administration of a taxane, it does reduce the cost associated with drug wastage.

Prophylactic cranial irradiation with combined modality therapy for patients with locally advanced non-small cell lung cancer

Central nervous system (CNS) metastasis is a significant problem for many patients with non-small cell lung cancer (NSCLC). The earlier data reported a high incidence of CNS metastasis in patients with locally advanced NSCLC who were treated with radiotherapy alone. However, poor control of both thoracic and extracranial systemic disease dominated the results of the early trials. The risk for CNS metastasis as the first site of failure remains a significant concern for patients who have completed modern combined modality therapy. With improvements in the treatment of thoracic and systemic disease, there is renewed interest in prophylactic cranial irradiation (PCI). The results from the Radiation Therapy Oncology Group (RTOG) trial of PCI to prevent CNS relapse in patients with locally advanced NSCLC are anticipated.

Survival in small cell lung cancer is independent of tumor expression of VEGF and COX-2

BACKGROUND

Preclinical data suggests that VEGF and COX-2 are potentially important mediators in the pathogenesis of small cell lung cancer (SCLC). Little is known about the frequency of tumor expression of VEGF and COX-2 in SCLC or the prognostic significance of this expression.

MATERIALS AND METHODS

Clinical records from 54 cases of SCLC were reviewed. Immunohistochemical stains for VEGF and COX-2 were performed on all tumor specimens.

RESULTS

Tumor VEGF expression was detected in 43 cases (81%) and COX-2 expression in 11 (20%). No significant association between VEGF or COX-2 expression and survival was observed.

CONCLUSION

This is the first study to assess the frequency and clinical significance of tumor VEGF and COX-2 expression in a large group of patients with SCLC. In this cohort, neither VEGF nor COX-2 expression impacted survival. The frequency of VEGF expression suggests that it merits further investigation as a therapeutic target in SCLC.

Cancer from an unknown primary site

Cancer from an unknown primary site (CUP) is frequently encountered in clinical practice. This review is designed to help physicians identify those patients with CUP that benefit from specific therapeutic approaches. The utility of pathologic and diagnostic tests in patients with CUP will also be discussed, as will the prognosis and appropriate treatment of these patients.

A phase II trial of 6-hydroxymethylacylfulvene (MGI-114, irofulven) in patients with advanced non-small cell cancer previously treated with chemotherapy

PURPOSE

To test the efficacy and safety of the novel antitumor agent MGI-114 (NSC 683863) in patients with advanced non-small cell lung cancer (NSCLC) previously treated with chemotherapy.

METHODS

A two-stage accrual design was used to ensure detection of a true response rate of at least 20% with a type I error of .04. Eligible patients received 11 mg/m2 daily for five consecutive days. Cycles were repeated every 28 days.

RESULTS

Fifteen patients received a total of 34 cycles of MGI-114. All patients had a performance status of 0 or 1. Eleven patients had previously received carboplatin and paclitaxel +/- radiation. Two patients had received cisplatin and CPT-11, one patient had received weekly paclitaxel, and one patient had received carboplatin and docetaxel. None of the first 15 patients enrolled experienced objective tumor response, and the study was closed. Forty percent of patients developed > or = grade 2 thrombocytopenia. Grade 3 nausea and > or = grade 2 vomiting were observed in 40% and 47% of patients respectively. Thirty-three percent of patients experienced > or = grade 2 fatigue.

CONCLUSIONS

MGI-114, at this dose and schedule, does not have significant activity as second line therapy for patients with advanced NSCLC.

A randomized Phase II trial in patients with carcinoma of an unknown primary site

BACKGROUND

Current therapy for patients with carcinoma of an unknown primary site (CUP) is inadequate. To develop less toxic and more effective therapies for patients with CUP, a multicenter, randomized, Phase II study was conducted. Patients with CUP received either carboplatin and etoposide (CE) or a combination of paclitaxel, 5-fluorouracil, and leucovorin (TFL).

METHODS

Patients randomized to Arm A received paclitaxel, 175 mg/m(2), intravenously over 3 hours on Day 1 followed by leucovorin, 300 mg, over 30-60 minutes and 5-fluorouracil, 350 mg/m(2), both intravenously on Days 1-3. Patients randomized to Arm B received etoposide, 100 mg/m(2), intravenously on Days 1-3 and carboplatin at an area under the curve of 6 on Day 1 only. The cycles in both treatment arms were repeated every 28 days. Patients were followed for tumor response, survival, and toxicity.

RESULTS

Thirty-four patients were enrolled, 32 of whom were evaluable for response. An identical overall response rate of 19% (95% confidence interval, 4-45%) was noted in each treatment arm. The median survival for the entire study population was 194 days. The median survivals observed in Arm A and Arm B were 251 days and 194 days, respectively (P = 0.91 [difference not significant]). Hematologic toxicity on Arm B was considerable with 29% of the patients developing neutropenia and fever. Toxicity on Arm A was modest.

CONCLUSIONS

In this randomized Phase II trial, CE and TFL appeared to have modest activity in CUP patients, with response rates similar to those reported with previously described chemotherapy regimens. Toxicity with CE was more severe than expected, although TFL was found to be well tolerated.

Myasthenia gravis after allogeneic bone marrow transplantation for lymphoblastic lymphoma

A 31-year-old female with lymphoblastic lymphoma developed myasthenia gravis (MG) 26 months after receiving an allogeneic bone marrow transplant (BMT) from an HLA-identical sister. She presented with classic symptoms and electromyographic evidence of the disorder approximately 2 weeks after electing to abruptly discontinue her immunosuppressive medications. She initially responded to steroids and acetylcholinesterase inhibitors. Her subsequent course has been characterized by episodes of moderately severe weakness that respond to intravenous immunoglobulin and prednisone. This case of post-transplant MG is only the second reported to have occurred in association with BMT for lymphoblastic lymphoma. Potential risk factors for the development of post-transplant MG are discussed including underlying hematological disorder, HLA phenotype, family history of MG, the presence of chronic GVHD, and recent cessation of immune suppression.

Seven-week continuous-infusion paclitaxel concurrent with radiation therapy for locally advanced non-small cell lung and head and neck cancers

The goal of these National Cancer Institute-sponsored phase I trials is to determine the feasibility, toxicity, and pharmacokinetics of continuous-infusion (24 hr/d, 7 d/wk, 7 weeks total) intravenous paclitaxel combined with standard, curative-intent thoracic radiation therapy (XRT) for previously untreated, locally advanced non-small cell lung cancer and squamous cell cancer of the head and neck (HNSCC). Eligible patients have locally advanced (T4NXM0 or TXN2-3M0) non-small cell lung cancer ineligible for potentially curative surgical resection or locally advanced HNSCC with an expected 5-year survival rate of less than 25%, as well as a good performance status, adequate hematologic, hepatic, and renal function, and no distant metastases. Non-small cell lung cancer patients receive a total tumor dose of 64.8 Gy megavoltage XRT in 7 weeks at 1.8 Gy once daily, 5 d/wk. Patients with HNSCC receive 70 Gy megavoltage XRT in 7 weeks at 2 Gy once daily, 5 d/wk. Paclitaxel is delivered by continuous intravenous infusion starting 48 hours before XRT and continuing for its duration. The dose of paclitaxel is escalated in cohorts of three patients in a standard phase I design. To date, 49 patients have been entered on both studies and 43 are evaluable for toxicity. Paclitaxel dose is currently at the 17 mg/m2/d dose level, with no dose-limiting toxicity thus far. Clinical outcomes suggest significant activity for this combination. This therapy is feasible and has been well-tolerated through current dose levels. Dose escalation is ongoing.