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Woodburn K.W.,Affymax Inc. | Schatz R.J.,Affymax Inc. | Fong K.-L.,Pennsylvania Biolab Inc. | Beaumier P.,SNBL United States Ltd.
International Journal of Immunopathology and Pharmacology | Year: 2010

Hematide™ is a synthetic PEGylated peptidic erythropoiesis stimulating agent (ESA) that is presently being developed for the correction of anemia in patients with chronic renal failure. Unlike currently marketed ESAs, Hematide does not possess any sequence homology to erythropoietin (EPO) and has not elicited moribund immune responses in animal safety studies thereby allowing the generation of a robust safety package. Animals administered marketed ESAs develop anti-EPO antibodies that null the effect of the administered ESA and neutralize endogenous EPO, resulting in severe anemia that precludes the interpretation of chronic safety studies. The primary objective of this study is to determine whether Hematide-specific antibodies are generated when male monkeys are exposed to high Hematide doses (10 mg/kg, intravenous [IV] and subcutaneous [SC]) administered at frequent dosing intervals (every two weeks) for a total of 9 doses; secondary objectives are to evaluate whether developed antibodies impact pharmacokinetics (PK) and pharmacology. In this study, no Hematide-specific antibodies were detected. Hematide exhibits a prolonged plasma half-life and slow clearance by either IV or SC administration. Hematide induced significant erythropoiesis with reticulocytosis and subsequent increases in red blood cells, hematocrit and hemoglobin (Hgb) levels. No erythropoietic differences were noted between the IV and the SC dosed groups with mean ± SD Hgb levels of 20.9 ± 2.5 and 20.3 ± 2.1 g/dL, respectively, occurring on Day 48, corresponding to Hgb increases of 6.5 and 6.7 g/dL, respectively, over pre-dose levels. In conclusion, Hematide is a potent erythropoiesis stimulating agent that exhibits plasma persistence in monkeys. Similar erythropoietic responses were produced following IV and SC administration. The absence of antibody development suggests that Hematide, at the doses and regimen described, has a low immunogenic potential in cynomolgus monkeys. © by Biolife, s.a.s. Source

Bowman C.J.,Pfizer | Evans M.,Pfizer | Cummings T.,Pfizer | Oneda S.,SNBL United States Ltd. | And 6 more authors.
Reproductive Toxicology | Year: 2015

Two intravenous studies with tanezumab, an anti-nerve growth factor monoclonal antibody, were conducted in pregnant cynomolgus monkeys to assess potential effects on pregnancy and pre- and postnatal development. Study 1 evaluated infants up to 12 months of age following weekly maternal dosing (0, 0.5, 4 or 30. mg/kg; 18 per group) from gestation day (GD) 20 through parturition. Study 2 evaluated infants 2 months postnatally following weekly maternal dosing (0, 0.5 or 30. mg/kg; 20-21 per group) from GD 20 through 48. In the absence of maternal toxicity, tanezumab increased stillbirth and post-birth infant mortality/morbidity, decreased infant growth and resulted in microscopic changes in the peripheral sympathetic and sensory nervous system of the infants at all doses. Decreased primary antibody responses and increased incidences in skin changes in infants were also observed. The no-observed-adverse-effect-level for maternal toxicity was 30. mg/kg and <0.5. mg/kg for developmental toxicity. © 2015 Elsevier Inc. Source

Miller C.L.,Massachusetts Institute of Technology | Miller C.L.,SNBL United States Ltd. | Muthupalani S.,Massachusetts Institute of Technology | Shen Z.,Massachusetts Institute of Technology | And 9 more authors.
PLoS ONE | Year: 2016

During a survey of clinical rectal prolapse (RP) cases in the mouse population at MIT animal research facilities, a high incidence of RP in the lamellipodin knock-out strain, C57BL/6-Raph1tm1Fbg (Lpd-/-) was documented. Upon further investigation, the Lpd-/- colony was found to be infected with multiple endemic enterohepatic Helicobacter species (EHS). Lpd-/- mice, a transgenic mouse strain produced at MIT, have not previously shown a distinct immune phenotype and are not highly susceptible to other opportunistic infections. Predominantly male Lpd-/- mice with RP exhibited lesions consistent with invasive rectal carcinoma concomitant to clinically evident RP. Multiple inflammatory cytokines, CD11b+Gr1+ myeloidderived suppressor cell (MDSC) populations, and epithelial cells positive for a DNA damage biomarker, H2AX, were elevated in affected tissue, supporting their role in the neoplastic process. An evaluation of Lpd-/- mice with RP compared to EHS-infected, but clinically normal (CN) Lpd-/- animals indicated that all of these mice exhibit some degree of lower bowel inflammation; however, mice with prolapses had significantly higher degree of focal lesions at the colo-rectal junction. When Helicobacter spp. infections were eliminated in Lpd-/- mice by embryo transfer rederivation, the disease phenotype was abrogated, implicating EHS as a contributing factor in the development of rectal carcinoma. Here we describe lesions in Lpd-/- male mice consistent with a focal inflammation-induced neoplastic transformation and propose this strain as a mouse model of rectal carcinoma. © 2016 Miller et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Source

Butt M.,Tox Path Specialists LLC | Evans M.,Pfizer | Bowman C.J.,Pfizer | Cummings T.,Pfizer | And 3 more authors.
Toxicological Sciences | Year: 2014

Tanezumab, an antibody to nerve growth factor, was administered to pregnant cynomolgus monkeys at 0, 0.5, 4, and 30 mg/kg weekly, beginning gestation day (GD) 20 through parturition (~GD165). Maternal tanezumab administration appeared to increase stillbirths and infant mortality, but no consistent pattern of gross and/or microscopic change was detected to explain the mortality. Offspring exposed in utero were evaluated at 12 months of age using light microscopy (all tissues), stereology (basal forebrain cholinergic and dorsal root ganglia neurons), and morphometry (sural nerve). Light microscopy revealed decreased number of neurons in sympathetic ganglia (superior mesenteric, cervicothoracic, and ganglia in the thoracic sympathetic trunk). Stereologic assessment indicated an overall decrease in dorsal root ganglion (thoracic) volume and number of neurons in animals exposed to tanezumab 4 mg/kg (n1/49) and 30 mg/kg (n1/41). At all tanezumab doses, the sural nerve was small due to decreases in myelinated and unmyelinated axons. Existing axons/myelin sheaths appeared normal when viewed with light and transmission electron microscopy. There was no indication of tanezumab-related, active neuron/nerve fiber degeneration/necrosis in any tissue, indicating decreased sensory/sympathetic neurons and axonal changes were due to hypoplasia or atrophy. These changes in the sensory and sympathetic portions of the peripheral nervous system suggest some degree of developmental neurotoxicity, although what effect, if any, the changes had on normal function and survival was not apparent. Overall, these changes were consistent with published data from rodent studies. © The Author 2014. Published by Oxford University Press on behalf of the Society of Toxicology. Source

Bowman C.J.,Pfizer | Chmielewski G.,Pfizer | Oneda S.,SNBL United States Ltd. | Finco D.,Pfizer | And 2 more authors.
Birth Defects Research Part B - Developmental and Reproductive Toxicology | Year: 2010

BACKGROUND: Insulin-like growth factor (IGF) signaling has been linked to tumor cell survival and tumorigenesis. The anti-IGF-1 receptor monoclonal antibody, figitumumab, has been developed as an anti-cancer therapeutic. As part of the safety evaluation, an embryo-fetal developmental toxicity study was conducted in the cynomolgus monkey. METHODS: Figitumumab was administered once weekly intravenously at a dose of 5, 15, or 100 mg/kg during the period of major organogenesis (gestation days [GD] 20-48) with scheduled cesarean section around GD100. Maternal endpoints included clinical observations, food consumption, body weights, hematology, placental weights, toxicokinetics, and immunogenicity. Fetal evaluations included viability; body weights; external, visceral, and skeletal examination (and measurements); drug exposure; and immunogenicity. RESULTS: There was a dose-dependent increase in embryo-fetal loss in the presence of decreased maternal food consumption and slight reduction in body weight. Figitumumab-related embryo-fetal developmental toxicity was observed as growth retardation exhibited by reduced fetal body weights at all doses with corresponding developmental delays in morphology. Treatment-related fetal structural malformations were also observed in the mid- and high-dose groups. CONCLUSIONS: Maternal figitumumab dosing only during the period of organogenesis was associated with pregnancy loss and fetal growth deficits; both considered consistent with inhibition of IGF signaling. Fetal malformations were also observed, and were considered secondary to altered placental function and/or reduced fetal growth; however, direct inhibition of IGF signaling in the conceptus cannot be ruled out. This appears to be the first report of treatment-related fetal anomalies with a monoclonal antibody when administered only during the period of major organogenesis. © 2010 Wiley-Liss, Inc. Source

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