Ischemic Optic Neuropathy.

PURPOSE OF REVIEW: Vision is often threatened or lost by acute ischemic damage to the optic nerves. Such pathology most often affects the anterior portion of the nerve and is visible on funduscopic examination. Ischemic optic neuropathy is associated with typical vascular risk factors and with one systemic disease in particular: giant cell arteritis (GCA). This article provides an overview of the three major classes of ischemic optic neuropathy, including information on risk factors, differential diagnosis, evaluation, and management. RECENT FINDINGS: Optical coherence tomography provides precise anatomic imaging in ischemic optic neuropathy, showing neural loss weeks before it is visible on examination. Refinements of optical coherence tomography reveal optic nerve microvasculature and may assist in understanding pathogenesis and verifying diagnosis. New diagnostic algorithms and cranial vascular imaging techniques help define the likelihood of GCA in patients with ischemic optic neuropathy. Finally, intraocular drug and biological agent delivery holds promise for nonarteritic ischemic optic neuropathy, whereas newer immunologic agents may provide effective steroid-sparing treatment for GCA. SUMMARY: It is essential to recognize ischemic optic neuropathy upon presentation, especially to determine the likelihood of GCA and the need for immediate steroid therapy. A broad differential diagnosis should be considered so as not to miss alternative treatable pathology, especially in cases with retrobulbar optic nerve involvement.

Recurrent Chemical Meningitis Due to Parasellar Epidermoid Cyst.

Intracranial epidermoid cysts are exceedingly rare lesions that result from a disorder of gastrulation. They are seen only in the pediatric patient population. We describe a 44-year-old Hispanic woman who presented with acute confusion. The family reported two months of progressive headaches and two weeks of fever, blurred central vision, and restricted visual fields. On examination, the patient appeared ill, with a low-grade fever and stiff neck. Neurological testing was limited but grossly non-focal. Computerized tomography (CT) of the head and magnetic resonance imaging (MRI) of the brain showed a large cystic mass arising in the sella, where it displaced the normal pituitary gland. Cerebrospinal fluid (CSF) showed mildly elevated opening pressure with high protein, low glucose, and neutrophilic pleocytosis. Extensive serum and CSF evaluation were negative for infectious agents. The patient was initially started on empiric treatment for presumed infectious meningoencephalitis. As tests for bacterial and viral pathogens were normal, she was switched to fluconazole. The mental status returned to normal and she was discharged home with close follow up. She returned one month later with a recurrent headache, nausea, and stiff neck. The examination showed meningismus but was otherwise non-focal. MRI of the brain showed no change in the parasellar mass. Repeat CSF showed an even higher white blood cell (WBC) count and protein with continued hypo-glycorrhachia. She underwent trans-nasal trans-sphenoidal hypophysectomy and pathology revealed a squamous epithelium-lined keratin-filled cyst suggestive of an epidermoid cyst. The patient responded well to surgery and was discharged on pituitary hormone supplements alone. To our knowledge, this is a first adult case of recurrent chemical meningitis secondary to a ruptured epidermoid cyst in the sella.

Multiple sclerosis: review of eye movement disorders and update of disease-modifying therapies.

PURPOSE OF REVIEW: To review important eye movement disorders in multiple sclerosis (MS) and update the ophthalmologist on disease-modifying therapies in MS, from the perspective of expert neurologists. RECENT FINDINGS: A large study confirmed that eye movement abnormalities in MS can be commonly identified by bedside examination. Identifying such ocular motility disturbances can assist in the diagnosis and prognosis for patients with MS. Articles published on such agents as oral teriflunomide and the biologics, natalizumab and alemtuzumab, have defined emerging roles of these treatments in the management of MS. SUMMARY: Many patients with MS suffer from isolated or a combination of eye movement disorders. Understanding their ocular motility disturbance patterns can help diagnose MS and correlate with the progression of MS. Exciting advances in MS disease-modifying treatments have been developed. Patients have more options than ever before of injectable, infusion and oral therapies. The therapeutic efficacy in lowering relapse rates is counterbalanced by these drugs' side-effects.

Re-evaluating the treatment of acute optic neuritis.

Clinical case reports and prospective trials have demonstrated a reproducible benefit of hypothalamic-pituitary-adrenal (HPA) axis modulation on the rate of recovery from acute inflammatory central nervous system (CNS) demyelination. As a result, corticosteroid preparations and adrenocorticotrophic hormones are the current mainstays of therapy for the treatment of acute optic neuritis (AON) and acute demyelination in multiple sclerosis.Despite facilitating the pace of recovery, HPA axis modulation and corticosteroids have failed to demonstrate long-term benefit on functional recovery. After AON, patients frequently report visual problems, motion perception difficulties and abnormal depth perception despite 'normal' (20/20) vision. In light of this disparity, the efficacy of these and other therapies for acute demyelination require re-evaluation using modern, high-precision paraclinical tools capable of monitoring tissue injury.In no arena is this more amenable than AON, where a new array of tools in retinal imaging and electrophysiology has advanced our ability to measure the anatomic and functional consequences of optic nerve injury. As a result, AON provides a unique clinical model for evaluating the treatment response of the derivative elements of acute inflammatory CNS injury: demyelination, axonal injury and neuronal degeneration.In this article, we examine current thinking on the mechanisms of immune injury in AON, discuss novel technologies for the assessment of optic nerve structure and function, and assess current and future treatment modalities. The primary aim is to develop a framework for rigorously evaluating interventions in AON and to assess their ability to preserve tissue architecture, re-establish normal physiology and restore optimal neurological function.

Neuromyelitis optica.

Neuromyelitis optica (NMO) is a disabling inflammatory condition that targets astrocytes in the optic nerves and spinal cord. Neuro-ophthalmologists must be particularly aware of this disorder because about half of patients present as isolated unilateral optic neuritis months or years before a disease-defining and often crippling bout of myelitis. NMO is easily confused with multiple sclerosis because it is characterized by relapses that lead to stepwise accrual of deficits. The best predictor of conversion from optic neuritis to clinical definite NMO is the presence of a serum antibody to aquaporin-4 called NMO-IgG. However, this test is currently only about 75% sensitive. Suspicion of NMO should be high in patients who present with vision of light perception or worse or who are left with acuity of 20/50 or worse after optic neuritis and in those with simultaneous bilateral optic neuritis or recurrent attacks. Acute NMO relapses are generally treated with high-dose intravenous steroids, with plasma exchange often used as a rescue therapy for those who do not respond. Preventative strategies against relapses currently use broad-spectrum or selective B-lymphocyte immune suppression, but their use is based on small, generally uncontrolled studies. Hopefully, the future will bring more sensitive tools for defining risk and predicting outcome, as well as more targeted and effective forms of therapy.

Phase I safety, pharmacokinetic, and pharmacodynamic study of ENMD-2076, a novel angiogenic and Aurora kinase inhibitor, in patients with advanced solid tumors.

PURPOSE: ENMD-2076 is a unique orally bioavailable Aurora kinase and VEGFR inhibitor. The purpose of this phase 1 study of ENMD-2076 was to determine the MTD, pharmacokinetic, and pharmacodynamic profiles and preliminary antitumor activity. EXPERIMENTAL DESIGN: Patients with refractory advanced solid malignancies were treated with ENMD-2076 orally with continuous once daily dosing. Doses from 60 to 200 mg/m(2) were evaluated using a standard 3 (to 4) + 3 design. Pharmacokinetic parameters were studied on days 1, 28, and 30 to 35 of cycle 1. Expanded MTD cohorts included patients with ovarian cancer, colorectal cancer, and refractory solid tumors. RESULTS: A total of 67 patients (46 F, 21M; ages 30-76) entered the study. Dose levels of 60, 80, 120, 200, and 160 mg/m(2) were evaluated. Two patients experienced grade 3 hypertension at 200 mg/m(2), and additional grade 3 neutropenia events limited tolerability at this dose. An intermediate dose of 160 mg/m(2) was determined to be the MTD. The most common drug-related adverse events included hypertension, nausea/vomiting, and fatigue. The pharmacokinetics of ENMD-2076 were characterized by a rapid absorption phase (T(max) 3-7.8 hours), a t(1/2) of 27.3 to 38.3 hours after a single dose, and dose proportional exposure. Decreased plasma sVEGFR2 was observed posttreatment. Two patients with platinum refractory/resistant ovarian cancer had RECIST partial responses. CONCLUSIONS: ENMD-2076 was well tolerated, had a linear pharmacokinetic profile, and showed promising antitumor activity, particularly in ovarian cancer. The recommended phase 2 dose of ENMD-2076 is 160 mg/m(2) administered orally once daily with continuous dosing.

Synthetic routes to pyrrolizine-1,5-dione derivatives by flash vacuum pyrolysis of amidomethylene derivatives of Meldrum's acid.

Methoxymethylene Meldrum's acid 1 reacts with 5- and 6-membered lactams in refluxing acetonitrile to give the N-substituted products 9-15. If the reactions are continued for extended times, the Meldrum's acid derivatives decompose to provide enamidoesters e.g. 22-24. Flash vacuum pyrolysis of the 5-membered ring products 9-13 provides reasonable yields of the fused pyrrolones 31-35. The constitution of the products is supported by X-ray crystal structures of 10, 12, 19, 32 and 34.

Vorinostat and bortezomib exert synergistic antiproliferative and proapoptotic effects in colon cancer cell models.

Despite the availability of several Food and Drug Administration-approved drugs, advanced inoperable colorectal cancer remains incurable. In this study, we focused on the development of combined molecular targeted therapies against colon cancer by testing the efficacy of the combination of the histone deacetylase inhibitor vorinostat with the proteasome inhibitor bortezomib to determine if this resulted in synergistic antitumor effects against colorectal cancer. The effects of the histone deacetylase inhibitor vorinostat in combination with the proteasome inhibitor bortezomib on the growth of two colorectal cancer cell lines were assessed with regard to proliferation, cell cycle arrest, and apoptosis. Treatment with the combination of vorinostat and bortezomib resulted in a synergistic decrease in proliferation of both colorectal cancer cell lines compared with treatment with single agents alone. This inhibition was associated with a synergistic increase in apoptosis as measured by caspase-3/7 activity and cleaved poly(ADP-ribose) polymerase. In addition, we observed an increase in the proapoptotic protein BIM and in the number of cells arrested in the G(2)-M phase of the cell cycle. Although p21 levels were significantly increased, short hairpin RNA knockdown of p21 did not lead to changes in proliferation in response to the combination of drugs, indicating that although p21 is a target of these drugs, it is not required to mediate their antiproliferative effects. These data indicate that combination treatment with vorinostat and bortezomib result in synergistic antiproliferative and proapoptotic effects against colon cancer cell lines, providing a rational basis for the clinical use of this combination for the treatment of colorectal cancer.

A phase I study of bortezomib, etoposide and carboplatin in patients with advanced solid tumors refractory to standard therapy.

PURPOSE: To evaluate the toxicity, pharmacological, and biological properties of the combination of bortezomib, etoposide, and carboplatin in adults with advanced solid malignancies. PATIENTS AND METHODS: Patients received escalating doses of bortezomib, etoposide, and carboplatin every 21 days. Surrogate markers of angiogenesis were evaluated. RESULTS: Twenty-four patients received 64 courses of therapy. The most common treatment-related adverse events were myelosuppression. Dose-limiting grade 3 and 4 neutropenia and thrombocytopenia were observed when bortezomib was given on days 1, 4, 8, 11. With revised dosing, the maximum tolerated dose (MTD) of bortezomib 0.75 mg/m(2) (days 1, 8), etoposide 75 mg/m(2) (days 1-3), and carboplatin AUC 5 (day 1) was well tolerated, and are the recommended doses for further studies with this combination. No objective responses were observed, however stable disease was noted for greater or equal to four cycles in nine highly refractory patients.

A phase I pharmacological and biological study of PI-88 and docetaxel in patients with advanced malignancies.

PURPOSE: This study evaluated the safety, toxicity, pharmacological properties and biological activity of PI-88, a heparanase endoglycosidase enzyme inhibitor, with fixed weekly docetaxel in patients with advanced solid malignancies. EXPERIMENTAL DESIGN: This was a phase I study to determine the maximal-tolerated dose of escalating doses of PI-88 administered subcutaneously for 4 days per week, along with docetaxel 30 mg/m(2) given on days 1, 8, 15 of a 28-day schedule. RESULTS: Sixteen patients received a total of 42 courses of therapy. No dose-limiting toxicities were observed despite escalation to the highest planned dose level of PI-88 (250 mg/day). Frequent minor toxicities included fatigue (38%), dysgeusia (28.5%), thrombocytopenia (12%), diarrhea (14%), nausea (12%), and emesis (10%) in the 42 courses. No significant bleeding complications were observed. One patient developed a positive anti-heparin antibody test/serotonin releasing assay with positive anti-platelet factor 4/PI-88 antibodies and grade 1 thrombocytopenia in cycle 5, and was withdrawn from the study without any sequelae. PI-88 plasma concentrations (mirrored by APTT) and urinary elimination were linear and dose-proportional. Docetaxel did not alter the pharmacokinetic (PK) profile of PI-88, nor did PI-88 affect docetaxel PK. No significant relationship was determined between plasma or urine FGF-2, or plasma VEGF levels and PI-88 dose/response. Although no objective responses were observed; 9 of the 15 evaluable patients had stable disease for greater than two cycles of therapy. CONCLUSION: PI-88 administered at 250 mg/day for 4 days each week for 3 weeks with docetaxel 30 mg/m(2) on days 1, 8 and 15, every 28 days, was determined to be the recommended dose level for phase II evaluation. This combination was well tolerated without severe toxicities or PK interactions.

A phase I safety, pharmacological, and biological study of the farnesyl protein transferase inhibitor, lonafarnib (SCH 663366), in combination with cisplatin and gemcitabine in patients with advanced solid tumors.

PURPOSE: This phase I study was conducted to evaluate the safety, tolerability, pharmacological properties and biological activity of the combination of the lonafarnib, a farnesylproteintransferase (FTPase) inhibitor, with gemcitabine and cisplatin in patients with advanced solid malignancies. EXPERIMENTAL DESIGN: This was a single institution study to determine the maximal tolerated dose (MTD) of escalating lonafarnib (75-125 mg po BID) with gemcitabine (750-1,000 mg/m(2) on days 1, 8, 15) and fixed cisplatin (75 mg/m(2) day 1) every 28 days. Due to dose-limiting toxicities (DLTs) of neutropenia and thrombocytopenia in initial patients, these patients were considered "heavily pre-treated" and the protocol was amended to limit prior therapy and re-escalate lonafarnib in "less heavily pre-treated patients" on 28-day and 21-day schedules. Cycle 1 and 2 pharmacokinetics (PK), and farnesylation of the HDJ2 chaperone protein and FPTase activity were analyzed. RESULTS: Twenty-two patients received 53 courses of therapy. Nausea, vomiting, and fatigue were frequent in all patients. Severe toxicities were observed in 91% of patients: neutropenia (41%), nausea (36%), thrombocytopenia (32%), anemia (23%) and vomiting (23%). Nine patients withdrew from the study due to toxicity. DLTs of neutropenia, febrile neutropenia, thrombocytopenia, and fatigue limited dose-escalation on the 28-day schedule. The MTD was established as lonafarnib 75 mg BID, gemcitabine 750 mg/m(2) days 1, 8, 15, and cisplatin 75 mg/m(2) in heavily pre-treated patients. The MTD in the less heavily pre-treated patients could not be established on the 28-day schedule as DLTs were observed at the lowest dose level, and dose escalation was not completed on the 21-day schedule due to early study termination by the Sponsor. No PK interactions were observed. FTPase inhibition was not observed at the MTD, however HDJ-2 gel shift was observed in one patient at the 100 mg BID lonafarnib dose. Anti-cancer activity was observed: four patients had stable disease lasting >2 cycles, one subject had a complete response, and another had a partial response, both with metastatic breast cancer. CONCLUSION: Lonafarnib 75 mg BID, gemcitabine 750 mg/m(2) days 1, 8, 15, and cisplatin 75 mg/m(2) day 1 on a 28-day schedule was established as the MTD. Lonafarnib did not demonstrate FTPase inhibition at these doses. Despite the observed efficacy, substantial toxicity and questionable contribution of anti-tumor activity of lonafarnib to gemcitabine and cisplatin limits further exploration of this combination.

Investigation of two dosing schedules of vandetanib (ZD6474), an inhibitor of vascular endothelial growth factor receptor and epidermal growth factor receptor signaling, in combination with irinotecan in a human colon cancer xenograft model.

PURPOSE: This in vivo study was designed to determine the optimal doses and schedules of vandetanib, a dual epidermal growth factor receptor (EGFR)-vascular endothelial growth factor receptor tyrosine kinase inhibitor, in combination with irinotecan in a murine xenograft model of human colon cancer. EXPERIMENTAL DESIGN: HT-29 tumor-bearing nude mice were treated with two doses of vandetanib (12.5 and 25 mg/kg/d) with or without irinotecan (100 mg/kg) using either sequential or concurrent schedules for 30 days. Tumor size was measured using standard variables, whereas the antiangiogenic response was evaluated using dynamic contrast-enhanced magnetic resonance imaging. Additionally, effects on EGFR-dependent signal transduction pathways and proliferation were assessed using immunohistochemistry. These pharmacodynamic end points were then evaluated for associations with antitumor efficacy and/or to plasma/tumor concentrations of vandetanib. RESULTS: The greatest antitumor efficacy was observed in the groups receiving the highest dose of vandetanib given continuously (concurrent schedule), alone or in combination with irinotecan. These dosing schedules resulted in significant effects on tumor vasculature, with decreased volume transfer constants, area under the curve, and permeability surface factor as well as increased gadolinium clearance after 30 days of treatment. In addition, these groups showed the greatest inhibition of EGFR signaling. Interestingly, tumor concentrations of vandetanib were increased by irinotecan in the concurrent schedule, possibly due to decreased tumor perfusion in this group. CONCLUSIONS: These data suggest that higher, sustained concentrations of vandetanib (versus intermittent), alone and in combination with irinotecan, result in optimal antitumor efficacy in this model and may have implications for the design of future clinical studies with this drug.

A phase I biological and pharmacologic study of the heparanase inhibitor PI-88 in patients with advanced solid tumors.

PURPOSE: PI-88 is a mixture of highly sulfated oligosaccharides that inhibits heparanase, an extracellular matrix endoglycosidase, and the binding of angiogenic growth factors to heparan sulfate. This agent showed potent inhibition of placental blood vessel angiogenesis as well as growth inhibition in multiple xenograft models, thus forming the basis for this study. EXPERIMENTAL DESIGN: This study evaluated the toxicity and pharmacokinetics of PI-88 (80-315 mg) when administered s.c. daily for 4 consecutive days bimonthly (part 1) or weekly (part 2). RESULTS: Forty-two patients [median age, 53 years (range, 19-78 years); median performance status, 1] with a range of advanced solid tumors received a total of 232 courses. The maximum tolerated dose was 250 mg/d. Dose-limiting toxicity consisted of thrombocytopenia and pulmonary embolism. Other toxicity was generally mild and included prolongation of the activated partial thromboplastin time and injection site echymosis. The pharmacokinetics were linear with dose. Intrapatient variability was low and interpatient variability was moderate. Both AUC and C(max) correlated with the percent increase in activated partial thromboplastin time, showing that this pharmacodynamic end point can be used as a surrogate for drug exposure. No association between PI-88 administration and vascular endothelial growth factor or basic fibroblast growth factor levels was observed. One patient with melanoma had a partial response, which was maintained for >50 months, and 9 patients had stable disease for >or=6 months. CONCLUSION: The recommended dose of PI-88 administered for 4 consecutive days bimonthly or weekly is 250 mg/d. PI-88 was generally well tolerated. Evidence of efficacy in melanoma supports further evaluation of PI-88 in phase II trials.

Sequence-dependent inhibition of human colon cancer cell growth and of prosurvival pathways by oxaliplatin in combination with ZD6474 (Zactima), an inhibitor of VEGFR and EGFR tyrosine kinases.

To date, clinical studies combining the new generation of targeted therapies and chemotherapy have had mixed results. Preclinical studies can be used to identify potential antagonism/synergy between certain agents, with the potential to predict the most efficacious combinations for further investigation in the clinical setting. In this study, we investigated the sequence-dependent interactions of ZD6474 with oxaliplatin in two human colon cell lines in vitro. We evaluated the in vitro antitumor activity of ZD6474, an inhibitor of vascular endothelial growth factor receptor (VEGFR), epidermal growth factor receptor (EGFR) and RET tyrosine kinase activity, and oxaliplatin using three combination schedules: ZD6474 before oxaliplatin, oxaliplatin before ZD6474, and concurrent exposure. Cell proliferation studies showed that treatment with oxaliplatin followed by ZD6474 was highly synergistic, whereas the reverse sequence was clearly antagonistic as was concurrent exposure. Oxaliplatin induced a G(2)-M arrest, which was antagonized if the cells were previously or concurrently treated with ZD6474. ZD6474 enhanced oxaliplatin-induced apoptosis but only when added after oxaliplatin. The sequence-dependent antitumor effects appeared, in part, to be based on modulation of compensatory prosurvival pathways. Thus, expression of total and active phosphorylated EGFR, as well as AKT and extracellular signal-regulated kinase, was markedly increased by oxaliplatin. This increase was blocked by subsequent treatment with ZD6474. Furthermore, the synergistic sequence resulted in reduced expression of insulin-like growth factor-I receptor and a marked reduction in secretion of vascular endothelial growth factor protein. ZD6474 in combination with oxaliplatin has synergistic antiproliferative properties in human colorectal cancer cell lines in vitro when oxaliplatin is administered before ZD6474.

Phase II trial of bevacizumab in combination with weekly docetaxel in metastatic breast cancer patients.

PURPOSE: To evaluate the safety and efficacy of bevacizumab and weekly docetaxel as first- or second-line therapy in patients with metastatic breast cancer (MBC). PATIENTS AND METHODS: Twenty-seven MBC patients received i.v. bevacizumab at 10 mg/kg on days 1 and 15 in combination with i.v. docetaxel 35 mg/m2 on days 1, 8, and 15 of a 28-day cycle. Primary end points were to assess toxicity, overall response rate, and progression-free survival. A secondary end point was to assess the relationship between plasma endothelial and cell adhesion markers and clinical outcomes. RESULTS: One-hundred fifty-eight treatment cycles were administered with a median of six cycles (range 1-15 cycles) per patient. The most common grade 4 toxicities per patient were as follows: 2 (7%)-pulmonary embolus, 1 (4%)-febrile neutropenia, and 1 (4%)-infection; grade 3 toxicities were 4 (15%)-neutropenia, 4 (15%)-fatigue, 2 (7%)-neuropathy, 2 (7%)-athralgias, 2 (7%)-stomatitis, 1 (7%)-pleural effusion, and 1 (4%)-hypertension. The overall response rate was 52% [95% confidence interval (95% CI), 32-71%], median response duration was 6.0 months (95% CI, 4.6-6.5 months), and the median progression-free survival was 7.5 months (95% CI, 6.2-8.3 months). In hypothesis-generating univariate and limited multivariate analyses, E-selectin was statistically significantly associated with response to the combination. CONCLUSION: Bevazicumab in combination with weekly docetaxel is active with acceptable toxicities in MBC. Additional studies evaluating E-selectin as a marker of response to bevacizumab-containing chemotherapy are warranted.