Establishment and Comprehensive Characterization of a Novel Preclinical Platform of Metastatic Retinoblastoma for Therapeutic Developments.

Purpose: Although there have been improvements in the management of metastatic retinoblastoma, most patients do not survive, and all patients suffer from multiple short- and long-term treatment toxicities. Reliable and informative models to assist clinicians are needed. Thus we developed and comprehensively characterized a novel preclinical platform of primary cell cultures and xenograft models of metastatic retinoblastoma to provide insights into the molecular biology underlying metastases and to perform drug screening for the identification of hit candidates with the highest potential for clinical translation. Methods: Orbital tumor, bone marrow, cerebrospinal fluid, and lymph node tumor infiltration specimens were obtained from seven patients with metastatic retinoblastoma at diagnosis, disease progression, or relapse. Tumor specimens were engrafted in immunodeficient animals, and primary cell lines were established. Genomic, immunohistochemical/immunocytochemical, and pharmacological analysis were performed. Results: We successfully established five primary cell lines: two derived from leptomeningeal, two from orbital, and one from lymph node tumor dissemination. After the intravitreal or intraventricular inoculation of these cells, we established cell-derived xenograft models. Both primary cell lines and xenografts accurately retained the histological and genomic features of the tumors from which they were derived and faithfully recapitulated the dissemination patterns and pharmacological sensitivity observed in the matched patients. Conclusions: Ours is an innovative and thoroughly characterized preclinical platform of metastatic retinoblastoma developed for the understanding of tumor biology of this highly aggressive tumor and has the potential to identify drug candidates to treat patients who currently lack effective treatment options.

Pharmacokinetics of Orbital Topotecan After Ophthalmic Artery Chemosurgery and Intravenous Infusion in the Swine Model.

Purpose: Surgery, multiagent systemic chemotherapy, and radiation are used for patients with orbital retinoblastoma but are associated with unacceptable short- and long-term toxicity (including death). We studied orbital and systemic exposure of topotecan in the swine model after ophthalmic artery chemosurgery (OAC) and intravenous (IV) delivery. Methods: Landrace pigs (n = 3) underwent 30-minute OAC of topotecan (4 mg), and samples were serially obtained from the femoral artery and from a microdialysis probe inserted into the lateral rectus muscle sheath of the infused eye as a surrogate of the orbital irrigation. Animals were recovered, and, after a wash-out period, plasma and microdialysate samples from the contralateral eye were collected after a 30-minute IV infusion of topotecan (4 mg). Samples were quantified by high-performance liquid chromatography, and population pharmacokinetic analysis was conducted using MonolixSuite. Results: After OAC, median topotecan exposure in the orbit was 5624 ng × h/mL (range 3922-12531) compared to 23 ng × h/mL (range 18-75) after IV infusion. Thus, topotecan exposure in the orbit was 218-fold (range 75-540) higher after OAC than after IV infusion despite comparable systemic exposure (AUCpl) between routes (AUCpl, OAC: 141 ng × h/mL [127-191] versus AUCpl, IV: 139 ng × h/mL [126-186]). OAC was more selective to target the orbit because the median (range) orbital-to-plasma exposure ratio was 44 (28-65) after OAC compared to 0.18 (0.13-0.40) after IV infusion. Conclusions: OAC of topotecan resulted in higher orbital exposure than after IV infusion and was a more selective route for local drug delivery. Patients with orbital retinoblastoma may benefit from a multimodal treatment strategy including OAC therapy.

Intensive Safety Monitoring of Rituximab (Biosimilar Novex® and the Innovator) in Pediatric Patients With Complex Diseases.

Although rituximab is widely used off-label for complex pediatric diseases, safety reports are limited. We aimed to report evidence of its use in clinical practice, to describe the incidence of adverse drug reactions (ADR) to rituximab biosimilar Novex® and innovator, and to identify risk factors for the development of ADR in a real-life follow-up cohort of pediatric patients with complex diseases. We conducted a prospective, longitudinal, observational, single-centre study in patients that received rituximab for any complex disease, and as part of an intensive pharmacovigilance program. Demographic, pharmacological, clinical, and drug-related data were collected for all patients. ADR-free survival, including infusion-related reactions (IRR) and delayed ADR (dADR), was estimated using Kaplan-Meier curves. Risk factors were evaluated by multivariable Cox regression models. In total, 77 patients (<19 y.o.) received 187 infusions of rituximab Novex® (n = 155) or innovator rituximab (n = 32) for neurologic (Neu), immune-hematologic-rheumatic (IHR), oncologic (O) diseases, and hematopoietic stem-cell transplantation (HSCT) or solid-organ transplantation (SOT). We recorded 29 IRR and 58 dADR that occurred in 27 (35.1%) and 29 (37.7%) patients, respectively. The respiratory tract was the most affected during IRR (29.6%) and hypogammaglobulinemia (37.9 %) was the most frequent dADR. First versus subsequent infusions (HR 5.4, CI95% 2.4-12.1, p<0.05), sex (boys vs. girls, HR 0.3, CI95% 0.1-0.8, and p<0.05), and diagnosis (Neu-IHR diseases vs. O-HSCT-SOT, HR 2.3, CI95% 1.02-5.4, and p < 0.05) were significantly associated with the development of IRR. For dADR, risk factors were diagnosis (Neu-IHR diseases vs. O-HSCT-SOT, HR 0.4, CI95% 0.2-0.9, and p < 0.05) and cumulative body surface area-normalized dosage (HR 1.0003, CI95% 1.0001-1.0006, and p < 0.05). The present is the largest real-world safety assessment of rituximab in Latin-American children with complex diseases supporting its use based on the overall acceptable safety. Identification of risk factors may contribute to optimization of off-label rituximab treatment in pediatrics.

Feasibility and results of an intraarterial chemotherapy program for the conservative treatment of retinoblastoma in Argentina.

BACKGROUND: The feasibility and results of intraarterial chemotherapy, also termed ophthalmic artery chemosurgery (OAC), for retinoblastoma in less developed countries have seldom been reported. PROCEDURE: A retrospective evaluation of a program of OAC in Argentina from 2010 to 2015. RESULTS: Ninety-seven eyes from 81 patients (61 bilateral) were analyzed. In 35 eyes, OAC was given as primary therapy and in 62 it was used for the treatment of tumors with partial response or those relapsing after systemic chemoreduction with focal therapy or external-beam radiotherapy. Twenty-two primarily treated eyes had group D and 13 groups B/C. A total of 400 procedures were carried out. Chemotherapy used included combinations of melphalan, carboplatin, and topotecan. There was no mortality associated with OAC. Toxicity included fever and neutropenia in five (1.25%), hypotension and bradycardia during anesthesia in two and femoral thrombosis in one, eyelid edema in nine, and neutropenia or thrombocytopenia in 28 cycles. With a median follow-up of 48.7 months (range 12-79), the 3-year probability of event-free survival (pEFS) (enucleation and/or radiotherapy were considered events) was comparable for patients who received first-line therapy and those treated at relapse (0.65 vs. 0.63, P = 0.5). In the former, the pEFS was 0.91 and 0.43 for groups B/C and D, respectively (P = 0.01). Two patients died of extraocular dissemination after refusal of enucleation. CONCLUSIONS: OAC was feasible with low toxicity. pEFS improved in all groups compared to the previous experience with systemic chemotherapy reducing the use of radiotherapy. The overall mortality associated with OAC is comparable to our previous experience with systemic chemoreduction.

Mixed micelles for encapsulation of doxorubicin with enhanced in vitro cytotoxicity on breast and ovarian cancer cell lines versus Doxil®.

Doxorubicin (DOX) is used as a "first-line" antineoplastic drug in ovarian and metastatic breast cancer. However, serious side effects, such as cardiotoxicity have been reported after DOX intravenous administration. Hence, we investigated different micelle-former biomaterials, as Soluplus®, Pluronic F127, Tetronic T1107 and d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) to develop a potential mixed micellar nanocarrier for DOX delivery. Since DOX hydrochloride is a poor candidate to be encapsulated inside the hydrophobic core of the mixed micelles, we assayed a hydrophobic complex between DOX and sodium deoxycholate (NaDC) as an excellent candidate to be encapsulated within polymeric micelles. The combination of T1107:TPGS (1:3, weight ratio) demonstrated the best physicochemical properties together with a high DL capacity (6.43% w/v). Particularly, DOX in vitro release was higher at acidic tumour microenvironment pH value (5.5) than at physiological counterpart (7.4). The hydrodynamic diameter of the DOX/NaDC-loaded mixed micellar system was 10.7nm (PDI=0.239). The in vitro cytotoxicity of the mixed micellar formulation resulted significantly (p<0.05) higher than Doxil® against ovarian (SKOV-3) and triple-negative breast cancer cells (MDA-MB- 231). Further, the in vitro cellular uptake assays demonstrated a significant increment (p<0.05) of the DOX intracellular content for the mixed micelles versus Doxil® for both, SKOV-3 (at 2, 4 and 6h of incubation) and MDA-MB-231 (at 4h of incubation) cells. These findings suggest that T1107:TPGS (1:3) mixed micelles could be employed as a potential nanotechnological platform for drug delivery of DOX.

Paclitaxel: What has been done and the challenges remain ahead.

In recent years, the nanotechnology has offered researchers the opportunity to solve the problems caused by the vehicle of the standard and first formulation of paclitaxel (Taxol®), while maximizing the proven antineoplastic activity of the drug against many solid tumors. Hence, different types of nanocarriers have been employed to improve the efficacy, safety, physicochemical properties and pharmacokinetic/pharmacodynamic profile of this drug. To date, paclitaxel is the unique drug that is marketed in three different nanoplatforms for its parenteral delivery: polymeric nanoparticles (Abraxane®), liposomes (Lipusu®), and polymeric micelles (Genexol®, Nanoxel® and Paclical®). Indeed, a fourth nanocarrier might be available soon, because phase III studies of Opaxio™, a polymeric-conjugated, are near completion. Furthermore, other several nanoformulations are currently in various stages of clinical trials. Therefore, it is only through the critical analysis of clinical evidence from these studies that we can get a more concrete idea of what has been achieved with pharmaceutical nanotechnology so far. This review attempts to summarize current information available regarding the clinical status and the physicochemical characteristic of different nanocarriers for paclitaxel delivery in cancer therapy. We present an overview of the preclinical and clinical data of these systems including their pharmacokinetics, dose and administration, adverse events and clinical efficacy.

Advances in therapy for the prevention of HIV transmission from mother to child.

INTRODUCTION: Actually, ~17.8 million women and 1.8 million children (<15 years) are currently infected with the Human Immunodeficiency Virus (HIV)/Acquired Immunodeficiency Syndrome (AIDS). Particularly, the majority of pediatric infections (>90%) resulted from 'HIV mother-to-child transmission' (MTCT), both in pregnancy, labour, delivery and later by breastfeeding. Due to its high pediatric incidence, MTCT represents a public health concern. Areas covered: In this review, we focus on available treatments and antiretroviral drugs recommended by the World Health Organization, and the main clinical investigations in antiretroviral pharmacotherapy to prevent the MTCT. Expert opinion: The MTCT has been improved dramatically in the last few years mainly due to prophylactic perinatal antiretroviral therapy for pregnant women living with HIV. However, there is still a milestone to reach since HIV MTCT remains as a public health challenge associated with MTCT though breastfeeding (post-natal transmission). In this context, different strategies could be employed as an attempt to reduce pediatric HIV infections. One of them involves the improvement of patient adherence to the HIV therapy. One possible solution is the development of novel long-acting formulations for prophylaxis of mothers and children, and a second possible solution is increase the inclusion of mothers and infants in care programs to more effectively prevent the vertical transmission.

Symptomatic bone langerhans cell histiocytosis treated at diagnosis or after reactivation with indomethacin alone.

This study evaluated the outcome of patients with symptomatic bone Langerhans cell histiocytosis (LCH) treated with indomethacin alone, either at diagnosis or after reactivation (after recurrence with previous therapies). We evaluated the nonrandomized use of oral indomethacin (2 mg/kg/d) in patients with symptomatic single-system bone LCH. From 1997 to 2012, 38 sequential patients were treated for a median of 4 months. Criteria of nonactive disease (NAD) after initial treatment (8 wk) were: no pain, no soft tissue involvement, no increase of size, or no new bone lesions. Twenty-two patients were treated at diagnosis: 18 showed NAD after initial treatment (2 patients who had bone reactivations were retreated with indomethacin and remain with NAD). Three patients improved and they are with NAD after treatment with indomethacin, steroids, or radiotherapy. One patient developed progressive bone disease and he is with NAD after treatment with steroids and chemotherapy. Sixteen patients were treated after reactivation, and all were with NAD after initial treatment: 5 reactivated and 4 remain with NAD after retreatment with indomethacin. Toxicity was not significant. We conclude that indomethacin is a well tolerated and active drug in patients with symptomatic bone disease. The results support the concept that chemotherapy may not be necessary for limited bone disease.

Psychological and physiological response of students to different types of stress management programs.

PURPOSE: To design, implement, and examine the psychoneuroendocrine responses of three different types of stress management programs. DESIGN: Randomly assigned. A pre/post experimental design comparing variables between three different programs and a control group. The first program included training in deep breathing, relaxation response, meditation, and guided imagery techniques (RRGI). The second program included training in cognitive behavioral techniques (CB). The third program included both RRGI and CB (RRGICB). SETTING: The study was conducted at Buenos Aires University. SUBJECTS: Participants (N  = 52) were undergraduate students. MEASURES: Anxiety, anger, hopelessness, neuroticism, respiration rate, and salivary cortisol levels were assessed. ANALYSIS: Wilcoxon signed rank test was used to investigate differences in pre and post variables. RESULTS: Subjects in the RRGI group showed significantly lower levels of anxiety (p < .011), anger (p < .012), neuroticism (p < .01), respiratory rate (p < .002), hopelessness (p < .01), and salivary cortisol (p < .002) after the treatment. Subjects in the CB group showed significantly lower levels of anxiety (p < .018), anger (p < .037), and neuroticism (p < .03) after the treatment. Subjects in the RRGICB group showed significantly lower levels of anxiety (p < .001), anger (p < .001), neuroticism (p < .008), hopelessness (p < .01), respiratory rate (p < .001), and salivary cortisol (p < .002) after the treatment. Subjects in the control group showed only one variable modification, a significant increase in cortisol levels (p < .004). CONCLUSIONS: The combination of deep breathing, relaxation response, meditation, and guided imagery techniques with CB seems to be effective at helping people to deal with stress.

A phase I study of periocular topotecan in children with intraocular retinoblastoma.

PURPOSE: To identify the maximum tolerated dose and dose-limiting toxicity of periocular topotecan in patients with relapsed or resistant intraocular retinoblastoma who are facing imminent enucleation. METHODS: For this phase I study, a starting dose of 0.5 mg of periocular topotecan administered through a 25-gauge needle was given with intrapatient escalation at a rate of 0.5 mg/cycle according to toxicity, up to a maximum dose of 2 mg. Two courses separated by 2 weeks were scheduled. Plasma levels of topotecan were measured by high-performance liquid chromatography in patients with available intravenous catheters. RESULTS: Seven eyes of five patients were treated with a total of 14 courses of periocular topotecan. Only mild orbital edema occurred, and grade 1 vomiting developed in the first patient that was controlled with ondansetron for the following courses. Dose-limiting toxicity was not reached and the maximum tolerated dose was set at the target dose of 2 mg (n=5 eyes). Lactone topotecan systemic exposure was lower than 55 ng/mL x h and it correlated linearly with dose in this small cohort. Even though the study was not designed to assess response, one eye was preserved after a partial response, but the remaining six were enucleated, either after a short period of disease stabilization followed by further therapy with other agents in five patients or by rapidly progressive disease in one. CONCLUSIONS: The dose limiting toxicity was not reached. Up to 2 mg of periocular topotecan could be given safely, but further studies are necessary to determine its effect on retinoblastoma (ClinicalTrials.gov number, NCT00460876).