Michelle T. Weckmann

Efficacy and safety of voretigene neparvovec (AAV2-hRPE65v2) in patients with RPE65-mediated inherited retinal dystrophy: a randomised, controlled, open-label, phase 3 trial

BACKGROUND Phase 1 studies have shown potential benefit of gene replacement in RPE65-mediated inherited retinal dystrophy. This phase 3 study assessed the efficacy and safety of voretigene neparvovec in participants whose inherited retinal dystrophy would otherwise progress to complete blindness. METHODS In this open-label, randomised, controlled phase 3 trial done at two sites in the USA, individuals aged 3 years or older with, in each eye, best corrected visual acuity of 20/60 or worse, or visual field less than 20 degrees in any meridian, or both, with confirmed genetic diagnosis of biallelic RPE65 mutations, sufficient viable retina, and ability to perform standardised multi-luminance mobility testing (MLMT) within the luminance range evaluated, were eligible. Participants were randomly assigned (2:1) to intervention or control using a permuted block design, stratified by age (<10 years and ≥10 years) and baseline mobility testing passing level (pass at ≥125 lux vs <125 lux). Graders assessing primary outcome were masked to treatment group. Intervention was bilateral, subretinal injection of 1·5 × 1011 vector genomes of voretigene neparvovec in 0·3 mL total volume. The primary efficacy endpoint was 1-year change in MLMT performance, measuring functional vision at specified light levels. The intention-to-treat (ITT) and modified ITT populations were included in primary and safety analyses. This trial is registered with ClinicalTrials.gov, number NCT00999609, and enrolment is complete. FINDINGS Between Nov 15, 2012, and Nov 21, 2013, 31 individuals were enrolled and randomly assigned to intervention (n=21) or control (n=10). One participant from each group withdrew after consent, before intervention, leaving an mITT population of 20 intervention and nine control participants. At 1 year, mean bilateral MLMT change score was 1·8 (SD 1·1) light levels in the intervention group versus 0·2 (1·0) in the control group (difference of 1·6, 95% CI 0·72-2·41, p=0·0013). 13 (65%) of 20 intervention participants, but no control participants, passed MLMT at the lowest luminance level tested (1 lux), demonstrating maximum possible improvement. No product-related serious adverse events or deleterious immune responses occurred. Two intervention participants, one with a pre-existing complex seizure disorder and another who experienced oral surgery complications, had serious adverse events unrelated to study participation. Most ocular events were mild in severity. INTERPRETATION Voretigene neparvovec gene replacement improved functional vision in RPE65-mediated inherited retinal dystrophy previously medically untreatable. FUNDING Spark Therapeutics.

Studies on chicken polyclonal anti-peptide antibodies specific for parathyroid hormonerelated protein (1–36)

Chicken polyclonal antibodies were prepared against a synthetic peptide corresponding to the first 36 N-terminal amino acids of parathyroid hormone-related protein (PTHrP) by immunizing laying hens. Significant increases of antibodies to PTHrP were first detected after the second immunization. Production of anti-PTHrP egg yolk antibodies peaked 1-2 weeks after the second through sixth immunizations and declined over a period of 2-4 weeks. Polyclonal IgG (IgY) to PTHrP was purified from the egg yolks with high levels of PTHrP specific binding. The anti-PTHrP IgG was used to develop a radioimmunoassay for PTHrP that was able to detect 100 pg PTHrP ml-1 (23 pM) in conditioned cell culture medium. The anti-PTHrP IgG was bound to a solid phase and utilized to immunopurify iodinated [Tyr36]-PTHrP (1-36). Anti-PTHrP IgG inhibited the in vitro biologic activity of PTHrP as demonstrated by the inhibition of adenylate cyclase stimulation in a rat osteoblast-like cell line (ROS 17/2.8). The anti PTHrP IgG was immunopurified and utilized for immunohistochemical localization of PTHrP in canine skin. Chickens were advantageous in producing large amounts of high affinity, neutralizing antibodies to a highly conserved mammalian protein such as PTHrP. The antibodies will be useful to investigate the function and metabolism of PTHrP in vivo and in vitro.

Effect of transforming growth factor-β1 on parathyroid hormone-related protein secretion and mRNA expression by normal human keratinocytes in vitro

Parathyroid hormone-related protein (PTHrP) is produced by a wide range of neoplastic and normal cells, including keratinocytes where it may regulate growth and differentiation. Transforming growth factor-β (TGF-β) is a growth factor produced by many cells, including keratinocytes where it regulates epidermal homeostasis. TGF-β has been reported to be cosecreted with PTHrP in some neoplasms and to stimulate PTHrP production by neoplastic keratinocytes. However, the effects of TGF-β on PTHrP production by normal keratinocytes are not well characterized. In this study, we investigated the effects of endogenous and exogenous TGF-β on PTHrP production by normal human foreskin keratinocytes. PTHrP secretion, mRNA expression, and mRNA transcription in vitro were determined by N-terminal radioimmunoassay, ribonuclease protection assay, and transient transfections. PTHrP production and secretion of latent TGF-β activity were greatest in proliferating keratinocytes prior to and at confluence of monolayer cultures. TGF-β1 increased PTHrP mRNA expression by normal keratinocytes in a dose-dependent manner with maximal stimulation at 6–12 h after treatment. In addition, keratinocytes treated with a monoclonal anti-TGF-β antibody expressed decreased levels of PTHrP mRNA. The increased levels of PTHrP mRNA following TGF-β1 treatment were owing, at least partly, to an increase in PTHrP mRNA stability. TGF-β1 failed to activate transcription of the luciferase reporter gene driven by either the human or mouse PTHrP promoters. In conclusion, TGF-β1 functions as a paracrine or autocrine regulator of PTHrP production in normal human keratinocytes, and this may play a role in the regulation of keratinocyte proliferation or differentiation.

Pharmaceutical Company Internet Sites As Sources of Information About Antidepressant Medications

AbstractAbstract Objective: To determine the informational content of nine pharmaceutical company websites about the antidepressant medication marketed by the company. Method: A structured, explicit review of materials found on pharmaceutical company websites about nine antidepressants for which no generic drug is available was conducted using eight popular search engines. The accessibility of these websites was also determined using these search engines. Results: Of 72 searches (one for each drug using each search engine), 46 yielded the pharmaceutical company website within the top 10 links. When outliers were removed, the company website was found in the top 10 links for 45 of 56 searches. All of the websites contain information of an advertising and emotive nature. Of the nine company websites, three contain anecdotal information; only two mention electroconvulsive therapy and four mention other types of drug therapy; and only one mentions the tradenames of other drugs. None of the websites mention drug costs, only one has efficacy statistics for the company’s drug and, although all of the websites mention at least one adverse effect of the company’s drug, only one lists percentages for adverse effects. Conclusion: The information about drugs for treating depression on pharmaceutical company websites aimed at consumers is limited and makes it difficult for consumers to compare drugs.

Hospice eligibility in patients who died in a tertiary care center

BACKGROUND Hospice is a service that patients, families, and physicians find beneficial, yet a majority of patients die without receiving hospice care. Little is known about how many hospitalized patients are hospice eligible at the time of hospitalization. METHODS Retrospective chart review was used to examine all adult deaths (n = 688) at a tertiary care center during 2009. Charts were selected for full review if the death was nontraumatic and the patient had a hospital admission within 12 months of the terminal admission. The charts were examined for hospice eligibility based on medical criteria, evidence of a hospice discussion, and hospice enrollment. RESULTS Two hundred nine patients had an admission in the year preceding the terminal admission and a nontraumatic death. Sixty percent were hospice eligible during the penultimate admission. Hospice discussions were documented in 14% of the hospice-eligible patients. Patients who were hospice eligible had more subspecialty consults on the penultimate admission compared to those not hospice eligible (P = 0.016), as well as more overall hospitalizations in the 12 months preceding their terminal admission (P = 0.0003), and fewer days between their penultimate admission and death (P = 0.001). CONCLUSION The majority of terminally ill inpatients did not have a documented discussion of hospice with their care provider. Educating physicians to recognize the stepwise decline of most illnesses and hospice admission criteria will facilitate a more informed decision-making process for patients and their families. A consistent commitment to offer hospice earlier than the terminal admission would increase access to community or home-based care, potentially increasing quality of life.

Medical manuscripts impact of hospice enrollment on cost and length of stay of a terminal admission.

Objective: To determine whether hospice enrollment at the time of a terminal admission alters the length of stay (LOS) or costs compared with patients not enrolled in hospice. Methods: Retrospective chart review of all nontraumatic inpatient deaths of patients with a previous admission in the preceding 12 months at an academic hospital. Results: 209 patients had a nontraumatic death and an admission in the year prior to the terminal admission. Patients enrolled in hospice had a shorter LOS (P = .02) and lower cost (P < .0001) than patients not enrolled at the time of their terminal admission. Conclusions: Enrollment in hospice during a terminal admission decreased cost and LOS. Hospice may be a way to provide more cost-effective, appropriate care to dying patients.

Dependence of Humoral Hypercalcemia of Malignancy on Parathyroid Hormone-related Protein Expression in the Canine Anal Sac Apocrine Gland Adenocarcinoma (CAC-8) Nude Mouse Model

Circulating parathyroid hormone-related protein (PTHrP) is the primary humoral factor in dogs with spontaneous humoral hypercalcemia of malignancy (HHM) and adenocarcinomas derived from apocrine glands of the anal sac. A canine apocrine adenocarcinoma model of HHM in nude mice (CAC-8) was developed and characterized. After 32 passages in vivo, a spontaneous variant of the tumor (CAC-8 Lo Ca) that has altered cellular morphology and that fails to induce HHM in tumor-bearing nude mice has been discovered. The hypercalcemic and nonhypercalcemic tumor lines were compared by tumor weight, effect on body weight, serum calcium concentration, plasma PTHrP concentration, histopathology, expression of PTHrP protein by radioimmunoassay and immunohistochemistry, and expression of PTHrP mRNA by in situ hybridization and northern blot analysis. Messenger RNA expression for other factors and cytokines known to alter PTHrP secretion or bone resorption in vivo, including tumor necrosis factor α (TNFα), interleukin (IL)-1, IL-6, and transforming growth factor β (TGFβ), were also measured in the adenocarcinomas. There was no significant difference in weight of individual tumors. Nude mice bearing the CAC-8 (Lo Ca) tumor maintained normal body weight as compared with non-tumor-bearing control mice. In contrast, mice with the CAC-8 (Hi Ca) tumor had markedly decreased body weights. The CAC-8 (Hi Ca) tumor-bearing mice had severe hypercalcemia (x~ = 13.4 mg/dl) and increased plasma concentrations of PTHrP (30.4 pM), whereas the CAC-8 (Lo Ca) tumor-bearing mice had a mean serum calcium concentration of 10.1 mg/dl and mildly increased PTHrP concentrations (5.7 pM) as compared with control mice (9.0 mg/dl and 1.0 pM, respectively). The original tumor (CAC-8 [Hi Ca]) is a well-differentiated adenocarcinoma, whereas the variant tumor (CAC-8 [Lo Ca]) is a solid carcinoma with both polygonal and spindle-shaped cells. The CAC-8 (Lo Ca) tumor had decreased PTHrP mRNA expression and protein synthesis. Messenger RNA expression of TGFβ, TNFα, IL-1, and IL-6 was similar in both tumors and was consistent with the central role of PTHrP in the induction of hypercalcemia in this animal model.

In vitro model of parathyroid hormone-related protein secretion from mammary cells isolated from lactating cows

Parathyroid hormone-related protein (PTHrP) is produced by the lactating mammary gland and is present in milk in a biologically active form. The goal of this investigation was to determine if cells cultured from the lactating mammary glands of cows would secrete PTHrP in vitro. Mammary acini were isolated from lactating cows at 1-6 wk after calving, and fresh or cryopreserved mammary acini were cultured for 14 d on Type I collagen. Cultures on thick layers of collagen (2.5 mm) were detached and allowed to contract on Day 6. PTHrP production was measured by N-terminal radioimmunoassay and bioassay (increased cAMP levels in ROS 17/2.8 osteoblast-like cells). The mammary cells reached confluence at Day 6. PTHrP production was low at Day 2 (< 0.5 ng/ml) but increased to peak production (2-4 ng/ml) at approximately Day 6 and remained constant until Day 14. Immunoreactive and bioactive PTHrP levels in the culture medium correlated well. The cultures produced lactoferrin (2,000-2,300 ng/ml and alpha s1-casein (14-19 ng/ml). Prolactin stimulated PTHrP production approximately 50% on Days 6-14. PTHrP production was increased approximately 100% by treatment with epidermal growth factor (10 ng/ml) for 2 d. Morphologic evaluation of cultures on thick, contracted collagen at Day 14 revealed an inner layer of mammary epithelial cells overlying myoepithelial cells and an outer layer of collagen containing stromal cells. Immunohistochemistry demonstrated positive staining for PTHrP and cytokeratin in both mammary epithelial and myoepithelial cells and alpha-smooth muscle actin in myoepithelial cells. These data demonstrated that cryopreserved mammary tissue from lactating cows could be cultured in vitro and secreted PTHrP in a regulated manner. This in vitro model will be useful to investigate the function and regulation of PTHrP in the lactating mammary gland.

Proton Magnetic Resonance Spectroscopy in adult cancer patients with delirium

Delirium is associated with a host of negative outcomes, including increased risk of mortality, longer hospital stay, and poor long-term cognitive function. The pathophysiology of delirium is not well understood. Cancer patients undergoing a bone marrow transplant (BMT) are at high risk for developing delirium and Proton Magnetic Resonance Spectroscopy ((1)H MRS) could lead to better understanding of the delirium process. Fourteen BMT patients and 10 controls completed (1)H MRS, positioned above the corpus callosum, shortly after delirium onset or at study end if no delirium occurred. In the BMT-delirium group, statistically significantly elevated tCho/tCr was found in contrast to the BMT-no delirium group. The BMT-delirium group also showed statistically significantly lesser NAA/tCho compared with both controls and the BMT-no delirium group. Elevated choline and reduced NAA indicate inflammatory processes and white matter damage as well as neuronal metabolic impairment. Further research is needed to separate the choline peaks, as well as more detailed collection of medication regimens to determine whether a higher choline concentration is a function of the delirium process or cancer treatment effects.

Regulation of parathyroid hormone-related protein expression in a canine squamous carcinoma cell line by colchicine.

The regulation of parathyroid hormone-related protein expression by colchicine, vinblastine, nocodazole, taxol, transforming growth factor-beta1 (TGFbeta1), and epidermal growth factor (EGF) was investigated in a canine squamous carcinoma cell line (SCC 2/88 cells). SCC 2/88 cells were stably transfected with a human P2/P3 PTHrP promoter-luciferase reporter gene construct and gene expression was measured after chemical treatments. The greatest increase in reporter gene expression was observed after colchicine treatment and small increases occurred after treatment with vinblastine, taxol, TGFbeta1, or EGF. Nocodazole had no significant effect on reporter gene expression. Colchicine also increased PTHrP steady state mRNA expression and PTHrP secretion by SCC 2/88 cells. These results demonstrated that PTHrP production was increased in SCC 2/88 cells by colchicine and suggested that factors or events during mitosis are capable of stimulating PTHrP production. An increase in PTHrP production during mitosis of malignant epithelial cells may be important in the pathogenesis of humoral hypercalcemia of malignancy.