Impaired Cardiac and Skeletal Muscle Energetics Following Anthracycline Therapy for Breast Cancer

BACKGROUND

Anthracycline-related cardiac toxicity is a recognized consequence of cancer therapies. We assess resting cardiac and skeletal muscle energetics and myocyte, sarcomere, and mitochondrial integrity in patients with breast cancer receiving epirubicin.

METHODS

In a prospective, mechanistic, observational, longitudinal study, we investigated chemotherapy-naive patients with breast cancer receiving epirubicin versus sex- and age-matched healthy controls. Resting energetic status of cardiac and skeletal muscle (phosphocreatine/gamma ATP and inorganic phosphate [Pi]/phosphocreatine, respectively) was assessed with 31P-magnetic resonance spectroscopy. Cardiac function and tissue characterization (magnetic resonance imaging and 2D-echocardiography), cardiac biomarkers (serum NT-pro-BNP and high-sensitivity troponin I), and structural assessments of skeletal muscle biopsies were obtained. All study assessments were performed before and after chemotherapy.

RESULTS

Twenty-five female patients with breast cancer (median age, 53 years) received a mean epirubicin dose of 304 mg/m2, and 25 age/sex-matched controls were recruited. Despite comparable baseline cardiac and skeletal muscle energetics with the healthy controls, after chemotherapy, patients with breast cancer showed a reduction in cardiac phosphocreatine/gamma ATP ratio (2.0±0.7 versus 1.1±0.5; P=0.001) and an increase in skeletal muscle Pi/phosphocreatine ratio (0.1±0.1 versus 0.2±0.1; P=0.022). This occurred in the context of increases in left ventricular end-systolic and end-diastolic volumes (P=0.009 and P=0.008, respectively), T1 and T2 mapping (P=0.001 and P=0.028, respectively) but with preserved left ventricular ejection fraction, mass and global longitudinal strain, and no change in cardiac biomarkers. There was preservation of the mitochondrial copy number in skeletal muscle biopsies but a significant increase in areas of skeletal muscle degradation (P=0.001) in patients with breast cancer following chemotherapy. Patients with breast cancer demonstrated a reduction in skeletal muscle sarcomere number from the prechemotherapy stage compared with healthy controls (P=0.013).

CONCLUSIONS

Contemporary doses of epirubicin for breast cancer treatment result in a significant reduction of cardiac and skeletal muscle high-energy 31P-metabolism alongside structural skeletal muscle changes.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT04467411.

Energetic and myocellular pathways in cardiac and skeletal muscle following anthracycline chemotherapy

Background

Anthracycline-related cardiac dysfunction is a recognised consequence of cancer therapies. Here we assess resting cardiac and skeletal muscle energic status as an early mechanistic pathway of myocyte derangement and explore molecular targets of skeletal myocyte metabolism, protein synthesis/degradation and mitochondrial biogenesis signalling.

Methods

We conducted a prospective, mechanistic, observational, longitudinal study of chemotherapy-naive breast cancer patients undergoing anthracycline-based chemotherapy, compared to a healthy control group. 31P-Magnetic Resonance spectroscopy in cardiac and skeletal muscle (phosphocreatine/gamma adenosine triphosphate (PCr/yATP) and inorganic phosphate/phosphocreatine (Pi/PCr) ratios respectively), cardiac magnetic resonance (CMR) imaging inclusive of T1 and T2 mapping, echocardiography-derived global longitudinal strain function, serum NT-pro-BNP and skeletal muscle biopsies from the right vastus lateralis were assessed before and after 3 cycles of Flurouracil, Epirubicin and Cyclophosphamide followed by 3 cycles of Docetaxel. Statistical significance was set at p<0.05.

Results

Twenty-five female breast cancer patients (median age 53 years, range 32–74 years) receiving a mean epirubicin dose 307 mg/m2) and twenty-eight controls (median age 44 years, range 23–65) were recruited. All study assessments in breast cancer patients at pre-chemotherapy stage were comparable to the matched healthy controls. However, following chemotherapy, breast cancer patients demonstrated a small but significant reduction in cardiac function (global longitudinal strain −22.9±3.9 vs −19.1±3.3%, p=0.01 and CMR-derived ejection fraction 65±5 vs 62±4%, p=0.047), a mild increase in CMR-derived indexed left ventricular volumes (end diastolic 65±10 vs 74±11 ml/m2, p=0.014 and end systolic 23±5 vs 28±5 ml/m2, p=0.01) as well as an increase in left ventricular T1 and T2-mapping (1289±29 vs 1321±31 ms, p=0.004 and 50±4 vs 55±7 ms, p=0.027, respectively) and serum NT-Pro-BNP (49±25 vs 108±84 pg/m, p=0.008). After epirubicin, there was significant reduction in cardiac PCr/yATP ratio (2.0±0.7 vs 1.2±0.6, p=0.007) and a significant increase in skeletal muscle Pi/PCr ratio (0.13±0.04 vs 0.22±0.2, p=0.008) – Figure 1.

Following chemotherapy, there was significant upregulation of skeletal myocyte protein synthesis (mammalian target of rapamycin, 0.44±0.4 vs 0.53±0.2, p<0.001) and degradation (Calcium/calmodulin dependent protein kinase II, 1.4±0.7 vs 2.7±1.1, p<0.001), metabolism (peroxisome proliferator-activated receptor gamma, 0.35±0.2 vs 0.60±0.1, p<0.001) and muscle mass regulator myostatin-2 (0.16±0.1 vs 0.24±0.1, p<0.001).

Conclusion

Contemporary doses of epirubicin for breast cancer result in significant reduction of cardiac and skeletal muscle high energy 31P-metabolism alongside skeletal myocellular alterations of protein synthesis and metabolic regulation pathways.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Tenovus ScotlandNHS Grampian Endowment fund

Consecutive ipsilateral inferior pole patella and superior patella sleeve fractures

We present a rare, previously undescribed case of a superior patella sleeve fracture in a skeletally immature adolescent male, just 1 month following surgery for an ipsilateral traumatic inferior pole patella fracture. This was initially missed resulting in a delay to surgery. We recommend a high index of suspicion is key in these patients who re-present following subsequent trauma and alternative X-ray views such as a flexed lateral can be extremely beneficial.

The effect of the SARS-CoV-2 pandemic on suspected cancer referrals at a regional head and neck unit

The novel coronavirus SARS-CoV-2, initially identified in late 2019 as a small case cluster, has rapidly become a global pandemic. Government restrictions, closure of primary care services, interruption of cancer screening programmes, and fear of contracting the virus have demonstrably led to a reduction in referrals for suspected cancer and delays to treatment across the United Kingdom. A retrospective analysis was carried out on suspected cancer referrals to the maxillofacial service at Aberdeen Royal Infirmary during the 12 months from March 2020, and compared with the 12 months prior. Suspected cancer referrals reduced by 38.6% (p < 0.001) during this period, with a reduction in the percentage referred by General Dental Practitioners. Further analysis shows a proportionate reduction in squamous cell carcinoma diagnoses, with other diagnoses remaining stable. Time from referral to first appointment, biopsy, and treatment showed no change. Stage at diagnosis and treatment modality was also unaffected. Assuming no change to the incidence of head and neck malignancies, over a third of new malignancies may have been undiagnosed during the 12 months from March 2020. Evidence for the impact of the pandemic is likely to become apparent as services return to pre-pandemic levels and these patients begin to present.

The Effect of Uncomplicated Knee Arthroscopy on C-reactive Protein and Erythrocyte Sedimentation Rate

BACKGROUND: Anticipated changes in erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) following uncomplicated knee arthroscopy have not previously been described. AIM: We aim to identify these values to aid the management of patients who re-present with a suspicion of infection. MATERIALS AND METHODS: Patients between 18 and 50 years undergoing day-case arthroscopic knee surgery under the care of the senior authors were recruited. Patients undergoing any bony intervention and those with a known inflammatory arthropathy were excluded from the study. Ethical approval was granted and patients consented to the study. ESR and CRP measurements were performed immediately prior to surgery, then at 1, 7, and 14 days postoperatively. RESULTS: A total of 29 patients consented to the study. A full set of results were achieved for 17 patients. There was a significant increase in CRP on day 1 and day 7 following knee arthroscopy with a mean increase of 4.55 mg/L (P = 0.003) on day 1 and 1.78 mg/L (P = 0.026) on day 7. ESR did not change significantly at any of the measured points. The maximum value for CRP was 16 mg/L on day 1 and 11.5 mg/L on day 7. All CRP measurements had returned to baseline (<5 mg/L) by 14 days. DISCUSSION AND CONCLUSION: Our study suggests that CRP measurement is a useful tool in the investigation of possible joint infection following simple knee arthroscopy. Continued elevation of CRP beyond 14 days or any significant elevation is not usual and suggests an abnormal post-operative recovery, which should prompt further investigation.

Hand Dominance and Walking Aid Use – Pre-determinants for Hip Fracture in the Elderly?

AIM: Left handedness has previously been associated with an increased risk of fracture for a number of sites but to the best of our knowledge no association between handedness and hip fracture has previously been reported. MATERIALS AND METHODS: Two separate 6-month prospective reviews of hip fracture patients aged over 65 years of age were conducted at two different hospitals, with the second review focusing on walking aid use. The patients with a neurological condition or contralateral hip prosthesis were excluded due to increased balance problems and falls risk. RESULTS: Hand dominance was recorded for 339 patients; 304 right and 35 left. A total of 91 patients were excluded from the study. Of the remaining 248 patients, 2.06 times as many fractured their hip on the side of their non-dominant hand. For the left-handed individuals this increased to 4.6 times. Walking aid use was recorded for 102 patients. Equal numbers of the right and left hip fractures were sustained for patients using no walking aids, a Zimmer frame or two walking sticks; while 97.7% of patients using one walking stick did so in their dominant hand, sustaining 84% contralateral hip fractures. CONCLUSION: The direction in which people fall and the causes of hip fractures is clearly multifactorial. However, we did find an association between hand dominance and hip fracture, especially when using a single walking aid. By being aware of this association, it may be possible to target both patient education and physiotherapy potentially reducing the number of patient falls and associated hip fractures.

Characterization of the Myocardial Inflammatory Response in Acute Stress-Induced (Takotsubo) Cardiomyopathy

•

Takotsubo cardiomyopathy is an acute heart failure syndrome often triggered by emotional or physical stress, where no treatment currently exists, and exact pathogenic mechanisms are unclear.

•

Rats in which takotsubo-like cardiomyopathy was induced showed localized myocardial inflammatory changes, including progressive inflammatory infiltrates and myofiber atrophy, that persisted over the 14-day time course examined.

•

Early neutrophil infiltrates were followed by clusters of myocardial macrophages, typically of an M1 proinflammatory phenotype, with no switch to M2 resolving macrophages; individual M2 macrophage levels, however, correlated with recovery in cardiac function. Human post-mortem myocardial tissue shared features of the experimental model demonstrating M1 macrophage clusters.

•

The persistent clinical symptoms and long-term morbidity/mortality observed in takotsubo patients may, in part, relate to chronic nonresolving myocardial inflammation.

Takotsubo cardiomyopathy is an acute stress-induced heart failure syndrome for which the exact pathogenic mechanisms are unclear, and consequently, no specific treatment exists. In an experimental model of stress-induced takotsubo-like cardiomyopathy, the authors describe the temporal course of a chronic inflammatory response post-induction, with an initial early influx of neutrophils into myocardial tissue followed by macrophages that are typical of a proinflammatory M1 phenotype, and a nonsignificant increase in systemic inflammatory cytokines. Post-mortem myocardium from the more complex clinical takotsubo patients share features of the study’s experimental model. These findings suggest modulators of inflammation could be a potential therapeutic option.

Abstract OT2-07-10: ATTAIN: Phase 3 study of etirinotecan pegol (EP) vs treatment of physician's choice (TPC) in patients (pts) with metastatic breast cancer (MBC) who have stable brain metastases (BM) previously treated with an anthracycline, a taxane, and capecitabine (ATC)

Background: EP is a next generation topoisomerase I inhibitor-polymer conjugate that provides continuous exposure to SN-38, the active metabolite. A BM mouse model showed high penetration and retention of SN-38 in CNS lesions, resulting in decreased size of CNS lesions and improved survival (OS) at concentrations achieved at the recommended dose in pts (Adkins BMC Cancer 2015). A Phase 3 trial (BEACON) of EP vs TPC in 852 pts with advanced BC did not meet its primary endpoint of OS (HR 0.087 p=0.08); a subset of 67 pts with stable BM showed improved OS (HR 0.51 [95% CI 0.30-0.86] p&lt;0.01) (Perez Lancet Oncol 2015). The current Phase 3 trial (ATTAIN) was designed for this subpopulation of pts having high unmet medical need.

Methods: Pts with MBC with locally treated stable BM will be randomized 1:1 to EP vs TPC in an open-label, randomized Phase 3 study. Eligibility includes ECOG PS 0 or 1; adequate organ function who received prior ATC (in neo/adjuvant or locally advanced/MBC setting) pts must have had ≥1 prior cytotoxic regimen for MBC (triple negative BC) ≥2 prior cytotoxic regimens and either 1 prior hormone therapy (HR+ BC) or 1 prior HER2 targeted therapy (HER2+ BC). Pts must have undergone definitive local therapy of BM (whole brain radiation [RT] stereotactic RT or surgical resection as single-agent or combination) signs/symptoms of BM must be stable with steroids unchanged or decreasing for ≥ 7 days prior to randomization. Primary endpoint is OS. Key secondary endpoints: ORR and PFS by RECIST v1.1 and RANO-BM, clinical benefit rate (ORR+SD ≥ 6 months) and QoL. Pts randomized to TPC will receive 1 of 7 IV cytotoxic agents. Pts are stratified by region, PS and receptor status. 350 pts will be randomized to obtain number of events required at 90% power to detect a statistically significant improvement in OS (hypothesizing HR=0.67) 1 interim analysis at 50% of deaths (130 events) will be performed. PK sampling and UGT1A1 testing will be performed in the EP arm; plasma ctDNA will be assessed for potential predictive markers of efficacy. Enrollment began early 2017. For enrollment information contact Dr. Alison Hannah, Dr. Mary Tagliaferri, or Minnie Kuo at StudyInquiry@nektar.com. NCT02915744

Citation Format: Tripathy D, Sara T, Seidman AD, Anders CK, Ibrahim N, Rugo HS, Twelves CJ, Diéras V, Müller V, Hannah A, Tagliaferri M, Cortés J. ATTAIN: Phase 3 study of etirinotecan pegol (EP) vs treatment of physician's choice (TPC) in patients (pts) with metastatic breast cancer (MBC) who have stable brain metastases (BM) previously treated with an anthracycline, a taxane, and capecitabine (ATC) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT2-07-10.

Dental occlusion and temporomandibular disorders

Data sourcesMedline, Scopus and Google Scholar.Study selectionTwo reviewers selected studies independently. English language clinical studies assessing the association between temporomandibular disorders (TMD) and features of dental occlusion were considered.Data extraction and synthesisStudy quality was assessed based on the Newcastle-Ottawa Scale (NOS) and a narrative synthesis was presented.ResultsIn all 25 studies (17 case-control, eight comparative) were included. Overall there was a high variability between occlusal features and TMD diagnosis. Findings were consistent with a lack of clinically relevant association between TMD and dental occlusion. Only two studies were associated with TMD in the majority (≥50%) of single variable analyses in patient populations. Only mediotrusive interferences are associated with TMD in the majority of multiple variable analyses.ConclusionsThe findings support the absence of a disease-specific association, there is no ground to hypothesise a major role for dental occlusion in the pathophysiology of TMDs. Dental clinicians are thus encouraged to move forward and abandon the old-fashioned gnathological paradig.

Abstract OT2-01-13: A phase 3, open-label, randomized, 2-arm international study of the oral dual PARP inhibitor talazoparib in germline BRCA mutation subjects with locally advanced and/or metastatic breast cancer (EMBRACA)

Background: Cancer cells with deleterious mutations in breast cancer susceptibility genes 1 and 2 (BRCA1/2) are deficient in the DNA double-strand break repair mechanism, rendering them highly dependent on the single-strand break repair pathway, regulated by poly(ADP-ribose) polymerase (PARP). Inhibition of PARP results in synthetic lethality in cells with a BRCA1/2 mutation because of accumulation of irreparable DNA damage; PARP inhibitors have the potential to be selectively toxic for BRCA-mutated cells. In addition to catalytic inhibition, it has been shown that some PARP inhibitors induce PARP trapping at sites of DNA damage. The capacity to trap PARP-DNA complexes varies widely across different PARP inhibitors and is not correlated with PARP catalytic inhibition. Preclinical models have shown trapping PARP on DNA is more potent at inducing cancer cell death than enzymatic inhibition of PARP alone. Talazoparib is a dual-mechanism PARP inhibitor that both inhibits the PARP enzyme and effectively traps PARP on DNA, preventing DNA damage repair and resulting in cell death in BRCA1/2-mutated cells. In preclinical studies, talazoparib at nanomolar concentrations showed the highest efficiency at trapping PARP-DNA complexes relative to other PARP inhibitors. In a previous phase 1/2 clinical study, talazoparib as monotherapy (1 mg once daily) resulted in a 50% response rate and an 86% clinical benefit rate at 24 weeks in 14 patients with a germline BRCA1/2 mutation and advanced breast cancer (aBC).

Methods: This open-label, randomized, 2-arm, international phase 3 trial (EMBRACA)

compares the efficacy and safety of talazoparib with protocol-specific physician's choice (capecitabine, eribulin, gemcitabine or vinorelbine) in patients with aBC. The primary objective is progression-free survival by central imaging. Secondary objectives are objective response rate, overall survival, safety and pharmacokinetics of talazoparib. Exploratory objectives include health-related quality of life measurements and biomarker research in blood and tumor samples that may permit characterization of mechanisms involved in tumor sensitivity and resistance to talazoparib. Key patient eligibility criteria include aged ≥18 years with histologically/cytologically confirmed breast cancer; locally advanced and/or metastatic disease appropriate for systemic single-agent cytotoxic chemotherapy; deleterious or pathogenic germline BRCA1/2 mutations by central laboratory; ≤3 prior cytotoxic chemotherapy regimens for advanced disease (prior platinum is allowed provided patients did not relapse within 6 months in the adjuvant setting or did not progress on platinum therapy); prior treatment with a taxane and/or anthracycline unless medically contraindicated; and ECOG performance status ≤2. Patients (N=429) will be randomized 2:1 to receive either talazoparib capsules (1 mg/day, 21-day cycles) or physician's choice treatment. This trial is currently enrolling patients from the USA, Europe, Israel, Ukraine, Russia, Korea, Australia, Taiwan and Brazil (NCT01945775).

This study is funded by Medivation, Inc.

Citation Format: Litton J, Ettl J, Hurvitz SA, Mina LA, Rugo HS, Lee K-H, Yerushalmi R, Woodward N, Goncalves A, Moreno F, Roche H, Im Y-H, Martin M, Bhattacharya S, Peterson A, Hannah A, Eiermann W, Blum J. A phase 3, open-label, randomized, 2-arm international study of the oral dual PARP inhibitor talazoparib in germline BRCA mutation subjects with locally advanced and/or metastatic breast cancer (EMBRACA) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT2-01-13.

Fractional flow reserve (FFR) versus angiography in guiding management to optimise outcomes in non-ST segment elevation myocardial infarction (FAMOUS-NSTEMI) developmental trial: cost-effectiveness using a mixed trial- and model-based methods

Background

In the Fractional flow reserve (FFR) versus angiography in guiding management to optimise outcomes in non-ST elevation myocardial infarction (FAMOUS) clinical trial, FFR was shown to significantly reduce coronary revascularisation, compared to visual interpretation of standard coronary angiography without FFR. We estimated the cost-effectiveness from a UK National Health Service perspective, based on the results of FAMOUS.

Methods

A mixed trial- and model-based approach using decision and statistical modelling was used. Within-trial (1-year) costs and QALYs were assembled at the individual level and then modelled on subsequent management strategy [coronary artery bypass graft (CABG), percutaneous coronary intervention (PCI) or medical therapy (MT)] and major adverse coronary events (death, MI, stroke and revascularisation). One-year resource uses included: material, hospitalisation, medical, health professional service use and events. Utilities were derived from individual EQ5D responses. Unit costs were derived from the literature. Outcomes were extended to a lifetime on the basis of MACE during the 1st year. Costs and QALYs were modelled using generalized linear models whilst MACE was modelled using logistic regression. The analysis adopted a payer perspective. Costs and outcomes were discounted at 3.5 %.

Results

Costs were related to the subsequent management strategy and MACE whilst QALYs were not. FFR led to a modest cost increase, albeit an imprecise increase, over both the trial [£112 (−£129 to £357)] and lifetime horizons [£133 (−£199 to £499)]. FFR led to a small, albeit imprecise, increase in QALYs over both the trial [0.02 (−0.03 to 0.06)] and lifetime horizons [0.03 (−0.21 to 0.28)]. The mean ICER was £7516/QALY and £4290/QALY over the trial and lifetime horizons, respectively. Decision remained high; FFR had 64 and 59 % probability of cost-effectiveness over trial and lifetime horizons, respectively.

Conclusions

FFR was cost-effective at the mean, albeit with considerable decision uncertainty. Uncertainty can be reduced with more information on long-term health events.

Electronic supplementary material

The online version of this article (doi:10.1186/s12962-015-0045-9) contains supplementary material, which is available to authorized users.

Right ventricular septal pacing as alternative for failed left ventricular lead implantation in cardiac resynchronization therapy candidates

AIMS

To compare the effects on left ventricular (LV) function of right ventricular (RV) septal pacing vs. cardiac resynchronization therapy (CRT) in patients with an indication for the latter. Cardiac resynchronization therapy is an effective therapy in patients with drug-refractory heart failure. Despite advances in implantation techniques, LV lead placement can be impossible in up to 10% of cases. We, therefore, assessed the effects of RV septal pacing from mid septum (RVmIVS) and outflow tract (RVOT) on cardiac performance, in comparison with CRT.

METHODS AND RESULTS

Twenty-two patients scheduled for CRT underwent dual-chamber temporary pacing. The ventricular lead was placed at the RV apex (RVA), RVmIVS, and RVOT in random order. Comprehensive echocardiography was performed in a baseline AAI mode and then at each RV position in dual chamber pacemaker function (D pacing, D sensing, D dual responses) mode and repeated on the next day following CRT implantation. Right ventricular apex pacing did not change any of the assessed echocardiography parameters. Both RVmIVS and RVOT pacing increased LV ejection fraction (EF): 29 ± 7% at baseline vs. 32 ± 6% (P = 0.02) and 32 ± 5% (P = 0.04) with RVmIVS and RVOT pacing, respectively. Similarly, the dyssynchrony index (Ts-SD) decreased: 50 ± 19 ms at baseline vs. 39 ± 17 ms (P = 0.04) and 37 ± 17 ms (P = 0.006) with RVmIVS and RVOT pacing, respectively. Cardiac resynchronization therapy further improved LVEF and Ts-SD to 36 ± 7% and 34 ± 15 ms, respectively, however, only LVEF was significantly higher compared with RVmIVS and RVOT pacing (P = 0.03 and P = 0.01 respectively). There were no significant differences in either LVEF or Ts-SD between RVmIVS and RVOT.

CONCLUSION

Right ventricular septal pacing from mid septum or RVOT pacing improves LVEF and LV synchrony in CRT candidates. Further improvement in LVEF was achieved by CRT, which remains the 'gold standard' therapy in these patients. However, RV septal pacing is worthy of further study as an alternative strategy when LV lead implantation fails.

Abstract P3-06-31: Etirinotecan pegol in patients with metastatic breast cancer (mBC): Modeling CA27.29 response and its correlation with tumor response

Background: Etirinotecan pegol (NKTR-102) is a unique topoisomerase 1 inhibitor that provides continuous exposure to SN38. In a Phase 2 study in pts with mBC whose disease had failed prior taxane-based treatment (Tx) etirinotecan pegol given q14d or q21d demonstrated a 29% overall response rate (J Clin Oncol 29: 2011 (suppl; abstr 1034)). Here we present the relationship between the dynamics of serum tumor marker CA27.29, etirinotecan pegol pharmacokinetics, and tumor response.

Methods: Data from 45 pts with at least two CA27.29 measurements (pre- & post-first dose), were fitted with a PK/PD model developed to correlate CA27.29 dynamics with SN38 exposure predicted from individual pt dosing history: d[CA27.29]/dt = Kin*exp(beta*t)*(1−[SN38]/(IC50+[SN38]))-Kout*[CA27.29]. Correlation of CA27.29 and RECIST response was investigated; % change of CA27.29 from baseline was also correlated with progression-free survival (PFS).

Results: CA27.29 vs time profiles were well described by the model, with a population mean plasma SN38 IC50 of 1.6 ng/mL. Typical minimum/maximum SN38 concentrations during Tx were 1.5/ 3 ng/mL for q14d and 0.9/ 2.4 ng/mL for q21d, indicating that both schedules resulted in SN38 exposure near the IC50. The half-life of CA27.29 decline was 15 days. 41 pts had pre- and post-Tx tumor measurements for correlation of CA27.29 response with tumor size. Of the 15 pts with RECIST CR or PR, 14 (93%) exhibited at least 10% declines in CA27.29 during Tx; all 5 pts with RECIST SD ≥ 6 months (mths) also manifested ≥10% declines, whereas only 45% (5/11) of pts with SD &lt; 6 mths showed ≥10% decline in CA27.29. Among the 10 pts with RECIST progressive disease (PD), 80% showed ≥10% CA27.29 elevations during Tx. The median maximum % reduction in observed CA27.29 from baseline during the course of Tx ranged from −55% to +30% and correlated with responder status as tabulated below.

Comparison of sample types for N-terminal pro-B-type natriuretic peptide measured on the Siemens Immulite 2500 and Dimension Vista LOCI methods

Background

Measurement of serum natriuretic peptides is recommended in patients with suspected heart failure. Assays for N-terminal pro-B-type natriuretic peptide (NT-proBNP) are available on several platforms and can be measured in serum or heparinized plasma. Siemens Healthcare Diagnostics do not recommend the use of serum for the Immulite NT-proBNP assay. Serum offers some practical advantages over plasma. We investigated the suitability of serum for use with the Immulite and Dimension Vista LOCI methods.

Methods

Paired serum and heparinized plasma samples were drawn from patients in the Cardiology Department over a 48-h period. Samples spanning the NT-proBNP concentration range 50–60,000 ng/L were analysed using the Siemens Immulite 2500 and Dimension Vista LOCI methods.

Results

There was no significant difference between serum NT-proBNP concentrations on either platform ( P = 0.0665). Plasma NT-proBNP measured using the Immulite were moderately higher than on Vista ( P < 0.0001). There was a small but statistically significant difference between plasma and serum NT-proBNP measured using the Immulite ( P = 0.0002) with plasma values higher than serum. A similar comparison between plasma and serum NT-proBNP measured using the Vista showed no difference ( P = 0.3662).

Conclusions

We have demonstrated the suitability of serum for use on the Immulite 2500. Bland–Altman comparative analysis indicated minimal bias between both serum methods near the clinical cut-off level below which heart failure is considered unlikely (400 ng/L) up to the highest concentration tested (60,000 ng/L).

Food-the way to a man's heart: a mini-case series of Campylobacter perimyocarditis

Campylobacter jejuni enteritis is 1 of the most common causes of food poisoning. Although an infrequent complication, Campylobacter associated perimyocarditis can have fatal consequences. This article illustrates 2 cases. We examine the types of Campylobacter jejuni responsible and report the observed male preponderance of this complication.

A study to evaluate the accuracy of ultrasound in the diagnosis of parotid lumps and to review the sonographic features of parotid lesions - results in 220 patients

AIM

To assess the accuracy of ultrasound in characterizing benign and malignant parotid lesions and to review their sonographic features.

MATERIALS AND METHODS

A retrospective analysis of 220 ultrasound examinations was undertaken in 220 patients who presented with palpable parotid lesions over an 11-year period and correlated with the clinico-histopathological findings. The original sonographic diagnosis was compared to the final histopathology and lesions characterized using previously established sonographic criteria.

RESULTS

Histopathology results were available for all patients. Two hundred and one patients had focal lesions: 29 carcinomas, 21 lymphomata and 151 benign lesions (including 69 pleomorphic adenomas and 54 Warthin's tumours); 19 patients did not have focal lesions. The initial ultrasound report was indeterminate in 25/201 focal lesions. In the remaining 176 lesions, the sensitivity, specificity, and diagnostic accuracy for malignancy of ultrasound was 91, 93, and 93%, respectively. There were four false-negatives and nine false-positives with a crossover of apparently benign and malignant features. Pleomorphic adenomas and Warthin's tumours were poorly differentiated using ultrasound. Additional impalpable parotid lesions or adenopathy were detected in 44 patients using ultrasound.

CONCLUSION

Ultrasound is a valuable adjunct to clinical examination, accurately differentiating benign from malignant lesions and diagnosing non-focal disease. There is an overlap in features of pleomorphic adenomas and Warthin's tumours and of some benign and malignant lesions. Diagnostic ultrasound should be combined with needle biopsy in most patients to maximize diagnostic yield.

Evolution of allometry in antirrhinum

Correlated variation in shape and size (allometry) is a major component of natural diversity. We examined the evolutionary and genetic basis for allometry using leaves and flower petals of snapdragon species (Antirrhinum). A computational method was developed to capture shape and size variation in both types of organ within the Antirrhinum species group. The results show that the major component of variation between species involves positively correlated changes in leaf and petal size. The correlation was maintained in an F2 population derived from crossing two species with organs of different sizes, suggesting that developmental constraints were involved. Identification of the underlying genes as quantitative trait loci revealed that the larger species carried alleles that increased organ size at all loci. Although this was initially taken as evidence that directional selection has driven diversity in both leaf and petal size, simulations revealed that evolution without consistent directional selection, an undirected walk, could also account for the parental distribution of organ size alleles.

Phase I/II study of MKC-1 and pemetrexed (PEM) as second-line therapy in patients (pts) with advanced non-small cell lung cancer (NSCLC)

e19005

Background: MKC-1 is a novel oral cell cycle inhibitor with preclinical activity against NSCLC cell lines including multi-drug resistant lines, and single agent activity in NSCLC pts. Binding targets of MKC-1 include microtubules, members of the importin-β family and AKT-mTOR. This phase 1/2 study evaluated MKC-1 in combination with PEM as second-line therapy in pts with advanced NSCLC. Methods: Eligible pts had NSCLC previously treated with one regimen for metastatic disease or disease progression within one year following adjuvant and neoadjuvant therapy. Phase 1 dose escalation used 3+3 design. Phase 2 pts were treated with MKC-1 at 75 mg/m2 given p.o. BID for 14 days along with PEM at 500 mg/m2 given i.v. on day 1 of each 21 day cycle. Following 4 cycles of combined treatment, single agent MKC-1 was continued as maintenance therapy. An interim analysis after 17 pts in phase 2 would allow accrual to continue provided one response was confirmed. Results: 27 pts were enrolled (8 in phase 1 and 19 in phase 2). Median age/PS for phase 2 is 64/1 and 89% had adenocarcinoma. Total # of treatment cycles to date for phase 2 pts is 95, with a median of 4 cycles. Of the 19 phase 2 pts, 18 were evaluable for tumor response. The best response was confirmed PR, noted in 3 pts. 5 additional pts (4 confirmed) had minor responses (>10% but <30% shrinkage). One additional pt continues on study with stable disease for >18 months. In phase 2 (n=19), all grade toxicities were anorexia (59%), fatigue (63%), nausea (58%), and dyspnea (48%). Grade 3/4 toxicities included fatigue (26%); neutropenia (22%); dyspnea, anorexia, AST and ALT elevation (11% each); nausea and constipation (5% each). 7 pts had at least one dose reduction of both PEM and MKC-1 and 3 additional pts had only MKC-1 reduced. Median PFS was 86 days with two pts continuing on study (treated for 530+ days and 140+ days, respectively). Conclusions: The phase 2 dose of MKC-1 (75 mg/m2 BID) and PEM (500 mg/m2) has been defined. The combination is well tolerated with 17% of patients achieving a confirmed PR thus far. A decision to proceed with additional accrual in this single arm study versus initiating a randomized phase 2 study of this combination is pending.

[Table: see text]

Tanespimycin (T) + bortezomib (BZ) in multiple myeloma (MM): Pharmacology, safety and activity in relapsed/refractory (rel/ref) patients (Pts)

3532

Background: Tanespimycin (17-AAG/KOS 953) disrupts Hsp90, a molecular chaperone of MM client proteins including IL-6 and IGF-1R that are key to MM growth, survival and drug resistance. Single agent T was well tolerated with modest anti- MM activity. Preclinical studies suggest potential synergy with BZ. Methods: Pts received BZ as IVB followed by 1-hr infusion of T on D1,4,8,11 q 21d. Results: 49 pts were enrolled in 7 cohorts (T 100- 340 mg/m2; BZ 0.7 - 1.3 mg/m2). PK of T was similar with or without BZ. Inhibition of 20S proteasome with T+BZ was not different vs. historical BZ single agent data. PBLs showed induction of Hsp70 4h post-infusion with maintenance of induction prior to T infusion across the dosing interval; pAKT plus total AKT were also reduced 4 and 72h following infusion. CD138 but not CD4 or CD8 cells from serial BM aspirates showed induction of apoptosis by flow cytometry. In addition, ↓expression of IGR-1R and IL-6R client proteins was seen after treatment. Safety: In Cohort 7, 19 pts received T 340 / BZ 1.3 mg/m2. Common all-grade (G) drug-related toxicity (n=19) included diarrhea (42%), nausea (32%), vomiting (26%), ↑ AST/ALT/Alk Phos (26%/21%/21%), myalgias (16%), and dizziness (16%). G3 thrombocytopenia was noted in 16% with no other G3 toxicity observed in more than 1 pt. DLT was seen in 2 pts: G3 myalgias/cramps and dehydration (reversible in both). G1–2 only treatment-emergent peripheral neuropathy was recorded in 15%. Activity: Responses have been seen across dose levels in BZ-naïve, pre-treated and ref pts (“ref” defined as no response to or disease progression within 60d of last dose of BZ-containing regimen). Specifically, 1 BZ-ref pt with 3 prior regimens had confirmed PR after 2 cycles and continues in Cycle 9 (M-spike ↓92%); a 2nd pt with 2 prior regimens achieved PR after 2 cycles and continues in Cycle 7; a 3rd pt with 7 prior regimens with confirmed PR after 3 cycles continues in Cycle 6. Conclusions: Treatment with T 340/ BZ 1.3 combination had generally manageable toxicity. Durable Hsp90 inhibition and similar proteasome inhibition (vs single-agent BZ) was seen. Importantly, anti-MM activity in BZ-ref pts was observed and further investigation of this combination in rel/ref MM is therefore warranted.

No significant financial relationships to disclose.

Phase I trial of KOS-1584 (a novel epothilone) using two weekly dosing schedules

2571

Background: KOS-1584 is an epothilone with increased potency and improved pharmacologic profile (enhanced water solubility, tumor penetration and reduced CNS exposure). Methods: Define the MTD, toxicity, PK, pharmacodynamics (PD), and early activity of KOS-1584 when administered to pts with advanced malignancies via 1-hr infusion on one of 2 schedules: Days 1, 8 & 15 every 4 weeks and Days 1 & 8 every 3 weeks. PD: assessed by serial sampling of PBMCs for soluble and polymerized microtubules by immunoblot. Methods: 37 pts enrolled in 10 cohorts (0.8 - 25 mg/m2) on the 4-week schedule (22 F; median age/ECOG/prior regimens of 56, 1 and 4, respectively). One pt has been enrolled at 16 mg/m2 on the 3-week schedule. For the 4-week schedule: DLTs were observed at 20 and 25 mg/m2; the 16 mg/m2 cohort is being expanded (using antidiarrheal prophylaxis). All episodes of DLT except 1 involved diarrhea with increasing severity after successive infusions despite maximal supportive care; 1 pt had typhlitis upon biopsy. An ovarian cancer pt experienced DLT consisting of Grade 3 weakness, neutropenia and peripheral sensory neuropathy (this pt had high plasma drug concentrations, possibly related to pre-existing severe hypoalbuminemia and ascites). Common all-grade drug- related toxicities (n=37): nausea (51%), diarrhea, fatigue (both 49%), vomiting (32%), anorexia (24%), constipation (24%), peripheral sensory neuropathy (19%) and anemia (16%). Neutropenia/leucopenia (Grade 1–2) observed at 16–25 mg/m2 dose levels. Except for the DLT involving peripheral neurotoxicity, all neurotoxicity was mild-to-moderate. PK (n=37): t½ 28.1 ± 8.7, Vz 627 ± 291 L, CL 18.0 ± 8.3 L/h. Cmax/AUC (25 mg/m2): 1,069 ± 2,456 ng/mL, 3,764 ± 2,579 ng/mL*h. Dose proportional increase in AUC and Cmax observed. ↑polymerized microtubules observed with maximal effect at end of infusion. Antitumor activity: NSCLC (1pt: confirmed PR; 10 cycles), ovarian cancer (1pt: 40% ↓CA125; 6 cycles), and H&N (1 pt: SD), these pts had all received doses ≥ 7.5 mg/m2. Conclusions: Accrual continues to define the optimal dose on both schedules; use of aggressive anti-diarrheal prophylaxis has been implemented.

No significant financial relationships to disclose.

Phase I trial of alvespimycin (KOS-1022; 17-DMAG) and trastuzumab (T)

1115

Background: Alvespimycin (A) inhibits the activity of Hsp90, resulting in degradation of client proteins, such as the HER2 receptor. In vivo, Hsp90 inhibition induces rapid degradation of HER2 with loss of pAKT, cyclin D2 and tumor growth inhibition. Methods: Pts receive standard weekly doses of T followed by A in escalating doses via IV doses over 1 hr. Define the recommended dose (RP2D), toxicity and signs of activity of T+A in pts with solid tumors. PK: assessed after the 1st and 4th infusion. PBLs: purified to investigate changes in intracellular signaling proteins by immunoblot. The RP2D will produce DLT in no more than 1/6 evaluable pts. Results: 21 pts enrolled in 3 cohorts (60, 80 and 100 mg/m2). Median age 53 yrs, range 31–75; median KPS 90; prior regimens not including hormonal therapy: median 6, range 1–13; prior T-regimens for MBC pts: median 3, range 0–9. Diagnoses: HER2+ MBC (n=18), ovarian (n=3). DLT was observed at the highest dose, consisting of 1 pt with hypoxia and ↓LVEF; an additional pt at this dose had Grade 3 ↑AST, however ↑hepatic metastases and ascites were observed. Drug-related toxicity: diarrhea (60%), fatigue, headache (both 45%), nausea, arthralgias (both 40%), dry eye and pain in extremity (both 25%); all Grade 1–2 severity except 1 episode of Gr3 fatigue and Gr3 diarrhea. PK (n=18): t½ 17.7 hr (32%CV); Clearance 18.1 L/hr (46%CV); Vz 438L (42%CV); no change upon weekly dosing. AUCinf/Cmax (100 mg/m2): 14268 ng*hr/mL (60%CV) and 2233 ng/mL (23.5%CV). HER2+ MBC activity: 1 pt (13 prior regimens; 3x T and 1x lapatanib) with evaluable disease showed near complete resolution of lung metastases by CT/PET with significant improvement in dyspnea; 3 pts with HER2+ MBC with SD (4, 5 and 7+ months). Ovarian CA activity: 1 pt (HER2 unknown; 13 prior regimens; 11+ months on-study) with evaluable disease showed near complete resolution of ascites and pleural effusion at end of Cycle 2 with ↓83% CA125. Dose-dependent increase in Hsp70 in PBLs; at 80 and 100 mg/m2, Hsp70 induction was maintained prior to successive weekly doses. Conclusions: Combination of T+A has signs of activity in H-refractory HER2+ MBC and refractory ovarian cancer. Definition of RP2D dose is pending. Toxicity has been manageable.

No significant financial relationships to disclose.

Phase 2 study of MKC-1 in patients (pts) with metastatic breast cancer (MBC) who have failed prior therapy with an anthracycline (A) and taxane (T)

11508

Background: MKC-1 (previously Ro 31–7453) is a novel cell cycle inhibitor with significant in vitro and in vivo activity against a wide range of tumor cell lines, including multi-drug resistant cell lines. Proteins identified as binding targets of MKC-1 include microtubules (colchicine binding site) and members of the importin-β family (proteins that play a critical role in nuclear transport and spindle formation). Objective responses (ORs) were observed in heavily pre-treated breast and NSCLC pts (Trigo Perez ASCO’03 A62; Kurup ASCO’03 A2725) treated at a dose of 95 mg/m2 BID given 14 days every 4 weeks with little toxicity. Salazar et al (2004 CCR 10:4374) recommended a higher oral dose (125 mg/m2 BID) on this schedule for further studies. This phase 2 trial is exploring the higher dose to maximize potential anticancer activity. Methods: Pts with MBC who had failed prior A and T and met eligibility criteria received MKC-1 at 125mg/m2 BID x 14d every 4 weeks. Pts with known treated and stable CNS metastases could enroll. Primary objective: OR by RECIST. Should 2 or more of the first 23 evaluable pts have an OR, enrollment will continue to 53 pts. Dose escalation/reductions are required based on toxicity (primarily neutropenia). Results: To date, a total of 20 pts have been enrolled (4 active in Cycles 1–5+). All female; median age/KPS of 60/90. 19% / 13% had received A / T in the neo/adjuvant setting; others had received A / T for metastatic disease. To date, a total of 48 cycles (median 2, range 1–8) were administered; of pts proceeding into Cycle 2, 40% and 20% had the dose increased or reduced, respectively. Severe drug-related toxicity (n=17) was observed in 3 pts (18%): ↑AST/ALT in 2 pts and parathesias in 1 pt. Drug related toxicity: nausea (47%), ↑ALT, diarrhea (both 24%), anemia, ↑AST, cough, fatigue, neutropenia and vomiting (all 18%). Two pts discontinued due to toxicity. One pt had complete resolution of measurable disease (1st observed after Cycle 4, confirmed after Cycle 6 with withdrawal for a new lesion at Cycle 8). An additional 2 pts had stable disease for 5 cycles (1 pt remains active). Conclusions: MKC-1 is well tolerated at the initial recommended dose for this schedule. Activity is observed in pts previously treated with A/T for MBC.

No significant financial relationships to disclose.

A Phase I study of the angiogenesis inhibitor SU5416 (semaxanib) in solid tumours, incorporating dynamic contrast MR pharmacodynamic end points

SU5416 (Z-3-[(2,4-dimethylpyrrol-5-yl)methylidenyl]-2-indolinone; semaxanib) is a small molecule inhibitor of the vascular endothelial growth factor receptor (VEGFR2). A Phase I dose escalation study was performed. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was used as a pharmacodynamic assessment tool. In all, 27 patients were recruited. SU5416 was administered twice weekly by fixed rate intravenous infusion. Patients were treated in sequential cohorts of three patients at 48, 65, 85 110 and 145 mg m-2. A further dose level of 190 mg m-2 after a 2-week lead in period at a lower dose was completed; thereafter, the cohort at 145 mg m-2 was expanded. SU5416 showed linear pharmacokinetics to 145 mg m-2 with a large volume of distribution and rapid clearance. A significant degree of interpatient variability was seen. SU5416 was well tolerated, by definition a maximum-tolerated dose was not defined. No reproducible changes were seen in DCE-MRI end points. Serial assessments of VEGF in a cohort of patients treated at 145 mg m-2 did not show a statistically significant treatment-related change. Parallel assessments of the impact of SU5416 on coagulation profiles in six patients showed a transient effect within the fibrinolytic pathway. Clinical experience showed that patients who had breaks of therapy longer than a week could not have treatment reinitiated at a dose of 190 mg m-2 without unacceptable toxicity. The 145 mg m-2 dose level is thus the recommended dose for future study.

Growth inhibition of foodborne and nosocomial pathogens by aqueous fraction of bearded Argostemma (Argostemma involucratum Hemsl., Rubiaceae)

The crude methanol extract of Bearded Argostemma (Argostemma involucratum Hemsl., Rubiaceae) showed a good and broad spectrum of antibacterial activity against both Gram-negative and Gram-positive bacteria. The activity was increased on fractionation (hexane, dichloromethane and water), particularly in the aqueous fraction which was more active than the methanol extract and streptomycin (no activity was shown against tested moulds). Both the hexane and dichloromethane fractions were inactive. The objective of this experiment was to investigate the antibacterial activity of hexane, dichloromethane, and aqueous fractions of Argostemma involucratum Hemsl. The aqueous fraction of Bearded Argostemma may be a possible new option for the treatment of bacterial infections.

18F-fluorodeoxyglucose positron emission tomography in evaluation of germ cell tumor after chemotherapy

OBJECTIVES

To evaluate the role of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) in the assessment of germ cell tumors after chemotherapy.

METHODS

We reviewed patients' records for the histologic findings and clinical outcome. 18F-FDG PET results were correlated with tissue histologic features where available; and if not available, the correlation was with the clinical outcome.

RESULTS

A total of 45 PET studies were performed on 38 patients (age range 19 to 64 years, median 31). All patients had received chemotherapy. In the nonseminomatous germ cell tumor (NSGCT) group, of the 31 patients with one scan, 18 PET scans were reported as positive, with only 2 not having active disease. Of the 12 negative scans, 6 showed teratoma, 1 tumor, and 5 did not show active disease. The equivocal scan revealed thyroid adenoma. In the seminoma group, the PET scans correlated well with the clinical and histologic outcomes. Four patients underwent salvage chemotherapy, and in this subgroup, the PET findings also correlated with the outcome.

CONCLUSIONS

(18)F-FDG PET is a promising tool as an adjunct to current imaging techniques in detecting residual viable germ cell tumor after chemotherapy. In NSGCT, a positive PET scan was accurate in 16 of 18 patients, although negative PET studies did not exclude the presence of disease, mainly because of the presence of teratoma. In seminoma, a negative 18F-FDG PET study correlated with a favorable clinical outcome. PET was also predictive of the response to salvage chemotherapy and was highly specific for active tumor in both NSGCT and seminoma.

Antimicrobial activity of Acalypha siamensis Oliv. ex Gage

The hexane, dichloromethane, ethyl acetate and methanol fractions of leaves of Acalypha siamensis Oliv. ex Gage were evaluated for antibacterial and antifungal activity. The antibacterial activity was more pronounced in the ethyl acetate and methanol extracts. No activity was shown against tested moulds.

Pharmacokinetics and interspecies scaling of a novel VEGF receptor inhibitor, SU5416

The pharmacokinetics and allometric relationships of SU5416, a novel small anti-angiogenesis agent, were studied. The pharmacokinetics of SU5416 were examined in mice, rats, dogs, and cancer patients. The in-vitro intrinsic clearance (CLint) was estimated from the in-vitro metabolism study in mouse, rat, dog, monkey and human liver microsomes. The parameters of interest were correlated across species as a function of bodyweight using an allometric approach. The steady-state volume of distribution (Vd(ss)), plasma clearance (CLs), and CLint of SU5416 were well correlated across species. The exponent of the allometric relationship (b) of the corresponding parameters was 0.92, 0.80 and 0.66, respectively. The elimination half-life (t1/2) was consistent across species and independent of bodyweight. The prediction of CLs, Vd(ss), CLint, and t1/2 in humans using the data from mouse, rat, and dog, and monkey (for CLint) was reasonably good (within 4-fold of the observed values). However, an improved prediction (within 2-fold of the observed values) of the corresponding parameters in humans was obtained when extrapolation from only the rodent data was performed, suggesting that the rodent data are sufficient for the scale-up of SU5416 pharmacokinetic parameters in humans. Using allometry, it was possible to achieve reasonable predictions of the pharmacokinetic parameters of SU5416 in cancer patients with various solid tumours.

Specific targeting, biodistribution, and lack of immunogenicity of chimeric anti-GD3 monoclonal antibody KM871 in patients with metastatic melanoma: results of a phase I trial

PURPOSE

KM871 is a chimeric monoclonal antibody against the ganglioside antigen GD3, which is highly expressed on melanoma cells. We conducted an open-label, dose escalation phase I trial of KM871 in patients with metastatic melanoma.

PATIENTS AND METHODS

Seventeen patients were entered onto one of five dose levels (1, 5, 10, 20, and 40 mg/m2). Patients received three infusions of KM871 at 2-week intervals, with the first infusion of KM871 trace-labeled with indium-111 (111In) to enable assessment of biodistribution in vivo. Biopsies of metastatic melanoma sites were performed on days 7 to 10.

RESULTS

Fifteen of 17 patients completed a cycle of three infusions of KM871. No dose-limiting toxicity was observed during the trial; the maximum-tolerated dose was therefore not reached. Three patients (at the 1-, 5-, and 40-mg/m2 dose levels) developed pain and/or erythema at tumor sites consistent with an inflammatory response. No normal tissue uptake of 111In-KM871 was observed, and tumor uptake of 111In-KM871 was observed in all lesions greater than 1.5 cm (tumor biopsy 111KM871 uptake results: range, 0.001% to 0.026% injected dose/g). The ratio of maximum tumor to normal tissue was 15:1. Pharmacokinetic analysis revealed a 111In-KM871 terminal half-life of 7.68 +/- 2.94 days. One patient had a clinical partial response that lasted 11 months. There was no serologic evidence of human antichimeric antibody in any patient, including one patient who received 16 infusions over a 12-month period.

CONCLUSION

This study is the first to demonstrate the biodistribution and specific targeting of an anti-GD3 antibody to metastatic melanoma in patients. The long half-life and lack of immunogenicity of KM871 makes this antibody an attractive potential therapy for patients with metastatic melanoma.

Renal artery stenosis: a disease worth pursuing

Consider renovascular hypertension (HT) when: Newly diagnosed hypertension presents with features that are atypical of essential hypertension; Resistant hypertension is associated with risk factors for atheroma; or Angiotensin-converting enzyme (ACE) inhibitor or angiotensin-II-receptor antagonist therapy is associated with increasing plasma creatinine levels. Atheromatous renovascular HT can often be managed medically, which includes intensive correction of cardiovascular risk factors. ACE inhibitors are probably second-line antihypertensives for patients with unilateral renal artery stenosis and two kidneys. First-line antihypertensives are diuretics, beta-blockers and calcium-channel blockers. Bilateral renal artery stenosis, or a unilateral stenosis in a patient with only one kidney, is an absolute contraindication to ACE inhibition.

A multi-institutional phase ii study of SU101, a platelet-derived growth factor receptor inhibitor, for patients with hormone-refractory prostate cancer

In a multi-institutional Phase II trial, we evaluated the efficacy of a platelet-derived growth factor receptor (PDGF-r) inhibitor, SU101, in patients with hormonerefractory prostate cancer. The patients received a 4-day i.v. loading dose of SU101 at 400 mg/m(2) for 4 consecutive days, followed by 10 weekly infusions at 400 mg/m(2). The primary study end points were a decline in prostate-specific antigen (PSA) and a decrease in measurable tumor. Secondary end points were time to progression and an effect on pain as measured by the Brief Pain Survey. Expression of PDGF-r was examined in both metastatic and archival primary prostate tumor samples. Forty-four patients were enrolled at four centers. The median age was 72 years, the median PSA was 223 ng/ml, and 21 patients had at least one prior chemotherapy. Thirty-nine patients are evaluable for PSA, and three patients demonstrated a PSA decline >50% from baseline (55-99.9% decrease). The median time to progression was 90 days. Of 19 patients evaluable for measurable disease, 1 patient had a partial response. Nine of 35 evaluable patients had significant improvement in pain. The most frequent adverse events were asthenia (75%), nausea (55%), anorexia (50%), and anemia (41%). PDGF-r expression was detected in 80% of the metastases and 88% of primary prostate cancers. The results of this trial may warrant further clinical studies with other PDGF-r inhibitors.