Glucocorticoids

Adeno-Associated Mediated Gene Transfer for Hemophilia B:8 Year Follow up and Impact of Removing “Empty Viral Particles” on Safety and Efficacy of Gene Transfer

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Abstract

Background: We have previously shown that a single intravenous administration of a self-complementary adeno-associated virus (scAAV) vector containing a codon-optimised factor IX gene, under control of a synthetic liver specific promoter and pseudotyped with serotype 8 capsid, (scAAV2/8-LP1-hFIXco) resulted in a dose-dependent increase in plasma FIX levels in all 10 enrolled severe hemophilia B (HB) patients (ClinicalTrials.gov:NCT00979238; Nathwani et al 2011). FIX activity was stably maintained for at least 3 years (Nathwani et al 2014) but concerns over FIX expression declining over time remain. This is because AAV-mediated transgene expression is mediated mainly by episomally retained viral genomes, which may be lost with natural hepatocyte turn-over. The only vector-associated adverse event was an asymptomatic rise in liver enzymes associated with a decline in FIX levels, occurring within 3 months of gene transfer in two-thirds of the patients treated at a dose of 2×1012 vector genomes(vg)/kg. Liver enzymes normalized with corticosteroids without complete loss of transgene expression. There was no long-lasting toxicity over a period of 3 years but further follow-up is required. The vector preparation used contained an excess of empty capsids, which lacked a full-length viral genome, and are therefore, non-functional but capable of provoking an immune response against transduced hepatocytes. Therefore, a new clinical preparation of scAAV2/8-LP1-hFIXco was manufactured from which most of the empty particles were removed by caesium chloride density centrifugation in the hope that this would reduce the risk of hepatotoxicity. We report on the evaluation of this new vector preparation in severe HB patients and provide an update on up to 8 years follow-up of our original cohort of patients.

Methods: Ten subjects were recruited in 2010-2012 to the initial dose-escalation/extension study arm, which entailed a single intravenous infusion of scAAV2/8-LP1-hFIXco (full: empty capsid ratio ~1:10) at a dose of either 2×1011vg/kg, 6×1011vg/kg or 2×1012vg/kg. Two severe HB patients (FIX <1%) were enrolled into the first and mid-dose cohorts, with six patients treated at the high dose. In a follow-on study arm, two severe HB subjects received a dose of 2×1012vg/kg of the new scAAV2/8-LP1-hFIXco preparation (full: empty capsid ratio 1:3) whilst the next 2 patients were treated at a dose of 5×1012vg/kg. In both arms, vector was administered without prophylactic immunosuppression but corticosteroids (starting at 60mg/day) were commenced if liver enzymes increased to ≥2 fold over baseline levels after gene transfer.

Results: Transgenic FIX activity levels have remained stable in all 10 subjects treated in the initial dose escalation/extension arm over a median follow-up of 6.7±1.0 years with mean levels in the three dose cohorts at the time of reporting of 1.9±0.6, 2.3±0.3 and 5.1±1.4 IU/l respectively. Over this period, annual FIX concentrate usage has dropped by 66% and annual bleed rate has declined by 82% when compared to pre-gene therapy levels. No late toxicity was observed. Neutralising antibodies to FIX were not detected in any patient but anti-AAV8 capsid-specific antibody levels persisted at high titres in 9 of 10 patients. In patients treated with the new preparation of scAAV2/8-LP1-hFIXco (median follow up = 2.1±1.4 years), mean FIX activity in the 2×1012vg/kg dose cohort was 2.6±0.7 IU/l. This is lower than observed previously at this dose level, but the difference is not statistically significant. Mean steady state FIX levels in the 5×1012vg/kg cohort were 17±5 IU/l. FIX antigen to activity ratio was 1:1. Elevation of serum alanine aminotransferase was observed in 3 of 4 patients treated with the new vector preparation, requiring treatment with corticosteroids.

Conclusion: This is the first report to demonstrate stable therapeutic expression of FIX in patients with severe HB over a period of 8 years following systemic administration of scAAV2/8-LP1-hFIXco without late toxicities. We show for the first time that reducing the capsid load by removing empty AAV capsids does not appear to reduce the incidence of hepatotoxicity in patients with severe HB suggesting that other factors are involved in the aetiology of this process.

source:https://ashpublications.org

Association between use of systemic and inhaled glucocorticoids and changes in brain volume and white matter microstructure: a cross-sectional study using data from the UK Biobank

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Abstract

Objective To test the hypothesis that systemic and inhaled glucocorticoid use is associated with changes in grey matter volume (GMV) and white matter microstructure.

Design Cross-sectional study.

Setting UK Biobank, a prospective population-based cohort study of adults recruited in the UK between 2006 and 2010.

Participants After exclusion based on neurological, psychiatric or endocrinological history, and use of psychotropic medication, 222 systemic glucocorticoid users, 557 inhaled glucocorticoid users and 24 106 controls with available T1 and diffusion MRI data were included.

Main outcome measures Primary outcomes were differences in 22 volumetric and 14 diffusion imaging parameters between glucocorticoid users and controls, determined using linear regression analyses adjusted for potential confounders. Secondary outcomes included cognitive functioning (six tests) and emotional symptoms (four questions).

Results Both systemic and inhaled glucocorticoid use were associated with reduced white matter integrity (lower fractional anisotropy (FA) and higher mean diffusivity (MD)) compared with controls, with larger effect sizes in systemic users (FA: adjusted mean difference (AMD)=−3.7e-3, 95% CI=−6.4e-3 to 1.0e-3; MD: AMD=7.2e-6, 95% CI=3.2e-6 to 1.1e-5) than inhaled users (FA: AMD=−2.3e-3, 95% CI=−4.0e-3 to −5.7e-4; MD: AMD=2.7e-6, 95% CI=1.7e-7 to 5.2e-6). Systemic use was also associated with larger caudate GMV (AMD=178.7 mm3, 95% CI=82.2 to 275.0), while inhaled users had smaller amygdala GMV (AMD=−23.9 mm3, 95% CI=−41.5 to −6.2) than controls. As for secondary outcomes, systemic users performed worse on the symbol digit substitution task (AMD=−0.17 SD, 95% CI=−0.34 to −0.01), and reported more depressive symptoms (OR=1.76, 95% CI=1.25 to 2.43), disinterest (OR=1.84, 95% CI=1.29 to 2.56), tenseness/restlessness (OR=1.78, 95% CI=1.29 to 2.41), and tiredness/lethargy (OR=1.90, 95% CI=1.45 to 2.50) compared with controls. Inhaled users only reported more tiredness/lethargy (OR=1.35, 95% CI=1.14 to 1.60).

Conclusions Both systemic and inhaled glucocorticoid use are associated with decreased white matter integrity and limited changes in GMV. This association may contribute to the neuropsychiatric side effects of glucocorticoid medication, especially with chronic use.

Low-dose glucocorticoid exposure increases osteoporotic fracture risk

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Among patients with various inflammatory conditions, exposure to glucocorticoids at doses as low as 5 mg per day may be associated with increased fracture risk, according to findings published in the Journal of Bone and Mineral Research.

“Fracture risk progressively increased with increasing levels of glucocorticosteroid exposure,” Akhila Balasubramanian, PhD, director with the Center for Observational Research at Amgen Inc., told Endocrine Today. “These trends were seen in the overall population as well as in patients younger than 50 years. We observed that fracture incidence in patients younger than 50 years who were exposed to glucocorticosteroids was as high as that observed in older (> 50 years) unexposed patients. Fracture risk decreased within months of steroid discontinuation.”

Balasubramanian and colleagues utilized the Truven Health MarketScan Commercial Claims and Encounters Database to follow 403,337 patients aged 18 to 64 years with rheumatoid arthritis (10%), asthma/chronic obstructive pulmonary disease (74%), irritable bowel disease (9%), multiple sclerosis, lupus and sarcoidosis. The researchers stratified fracture incidence rates per 1,000 person-years by prednisone-equivalent doses. They used Cox’s proportional hazard models to evaluate risk by daily and cumulative dose, and by time since cessation of glucocorticoids, adjusted for baseline characteristics.

At the end of follow-up, 72% patients had received systematic glucocorticoids during the study, according to researchers, with 69% of those exposed younger than 50 years. Sixty percent of exposed patients received cumulative doses of less than 675 mg (equivalent to 7.5 mg per day for 90 days), and 81% had short-term exposures between 1 and 90 cumulative days. Researchers identified 4,405 post-index fractures in the cohort, including 1,547 clinical vertebral fractures and 685 hip fractures.

Compared with incidence rates during unexposed time, fracture incidence approximately doubled in the presence of glucocorticoid exposures, even at the lowest daily doses of less than 5 mg per day (incidence rate = 9.33 per 1,000 person-years; 95% CI, 7.29-11.77) vs. unexposed (incidence rate = 4.87, 95% CI, 4.72-5.02), according to researchers. Results persisted in patients both older and younger than 50 years.

Unadjusted fracture incidence increased with increasing exposure for all exposure metrics, with very modest increases for peak dose, the researchers wrote.

Fracture incidence in patients with cumulative doses of 5,400 mg or higher (equivalent to 7.5 mg per day for 2 years), or patients with more than 365 days of glucocorticoid exposure, were nearly twice that of patients with cumulative doses ranging from 2,700 mg to 5,400 mg cumulative dose, or 81 to 365 days of glucocorticoid exposure. Fracture incidence in these patients with the highest doses and exposures were nearly triple that of unexposed patients, according to researchers.

Comparable patterns were revealed for clinical vertebral fractures and hip fractures, although daily dose for hip fractures did not exhibit the dose-response trend, the researchers wrote.

Adjusted HRs suggested significantly elevated fracture risk at daily doses as low as less than 5 mg per day, as well as a dose-response increase in fracture risk with increased cumulative dose. The risk at cumulative doses of less than 5,400 mg were roughly 2.5-fold higher vs. no exposure. Adjusted analyses stratified by cumulative dose corroborated the increased fracture risk at daily doses as low as less than 5 mg at cumulative doses greater than 5,400 mg.

Age-stratified descriptive analyses found a dose-dependent increase of fracture incidence with higher cumulative exposure to glucocorticoids in patients younger than 50 years and in patients aged 50 years or older.

In individuals younger than 50 years, there was a fracture incidence rate range of 2.44 per 1,000 person-years in never-exposed patients to five to six per 1,000 person-years in those with the highest cumulative exposures. Patients aged 50 years and older had incidence rate ranges between roughly six and 17 per 1,000 person-years based on exposure levels. There was an increase in fracture incidence rates at the lowest daily doses in both the younger and older patients; however, the older age group only showed a clear dose-response pattern of fracture incidence with higher daily doses. At doses of 5,400 mg or higher, patients younger than 50 years had incidence rates of 5.69 (95% CI, 4.32-7.35), whereas older patients had incidence rates of 17.10 (95% CI, 14.97-19.45).

Fracture risk decreased significantly within months after glucocorticoid discontinuation, according to researchers.

“The literature indicates that bone loss and associated fracture risk is often not well managed among patients using glucocorticosteroid therapy,” Balasubramanian said. “Based on the findings of our study as well as previous studies, physicians treating their patients with glucocorticosteroid therapy would be well advised to monitor and manage the bone health of these patients, including consideration of appropriate treatments for reduction of fracture risk.” – by Jennifer Byrne

For more information:

Akhila Balasubramanian, PhD, can be reached at aromano@webershardwick.com.

Disclosures: Amgen supported this study. Balasubramanian reports she is an employee of and stockholder in Amgen. Please see the study for the other authors’ relevant financial disclosures.

Correction: Sixty-nine percent of those exposed younger than 50 years, and the risk at cumulative doses of less than 5,400 mg were roughly 2.5-fold higher vs. no exposure. Endocrine Today regrets the error.

PERSPECTIVE

BACK TO TOP 

Michael Lewiecki

Glucocorticoids are used to treat many chronic inflammatory conditions. Adverse effects of long-term glucocorticoid therapy include disruption of bone remodeling, decrease in bone mineral density and increased fracture risk. Most patients on glucocorticoids are not being treated to mitigate the undesirable skeletal effects. A better understanding of the skeletal effects of glucocorticoids in diverse groups of patients may lead to more effective treatment.

The report by Balasubramanian and colleagues described the findings of a retrospective analysis of a large administrative claims database with chronic inflammatory diseases. This included more than 400,000 patients who were newly diagnosed with rheumatoid arthritis, asthma/chronic obstructive lung disease, inflammatory bowel disease, multiple sclerosis, lupus or sarcoidosis, 72% of whom had exposure to glucocorticoids.

Over 5 years with more than 2.4 million person-years of observation, 4,405 incident fractures were identified, including 1,547 clinical vertebral fractures and 685 hip fractures. Fracture rates were elevated in patients younger than 50 years of age as well as in those 50 years and older. The risk of fractures was greater with increasing levels of glucocorticoid exposure, but the risk was also elevated with prednisone equivalent doses of less than 5 mg per day. Fracture risk decreased within months of stopping glucocorticoids.

This study adds to the body of knowledge concerning the adverse skeletal effects of glucocorticoids. The findings suggest that we should be vigilant for potential skeletal harm with glucocorticoids, even in younger patients treated with low doses. Pharmacological therapy for glucocorticoid-induced osteoporosis should be used according to well-established guidelines. It is reassuring that fracture risk rapidly diminishes with discontinuation of glucocorticoids.

E. Michael Lewiecki, MD

Director of New Mexico Clinical Research & Osteoporosis Center
Director of Bone Health TeleECHO at University of New Mexico Health Sciences Center

Springing a Leak

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52-year-old man presented to the emergency department with general weakness and swelling in his legs. Symmetric swelling had begun 4 weeks earlier and had progressed to the point that it was difficult for him to wear shoes.

Springing a Leak

The nephrotic syndrome is most commonly caused by membranous nephropathy, focal segmental glomerulosclerosis, minimal-change disease, or membranoproliferative glomerular disease.

Clinical Pearls

• What are the diagnostic criteria for the nephrotic syndrome?

The diagnostic criteria for the nephrotic syndrome include nephrotic-range proteinuria (>3.5 g in 24 hours), hypoalbuminemia (<3 g of albumin per deciliter), peripheral edema, and hyperlipidemia.

• What are some of the causes of the nephrotic syndrome?

The nephrotic syndrome is most commonly caused by membranous nephropathy, focal segmental glomerulosclerosis, minimal-change disease, or membranoproliferative glomerular disease. All forms of the nephrotic syndrome may be associated with neoplasms, particularly lymphoma, which may cause a paraneoplastic-associated membranous nephropathy or minimal-change disease. Other secondary causes of the nephrotic syndrome include medications (e.g., nonsteroidal antiinflammatory agents); hepatitis or other chronic infections, including human immunodeficiency virus (HIV) infection; systemic lupus erythematosus; and amyloidosis.

Morning Report Questions

Q: Under what circumstances is hypothyroidism a possible complication of the nephrotic syndrome?

A: Hypothyroidism is an unusual complication of the nephrotic syndrome. The majority (99%) of T4 in the serum is bound to thyroid-binding proteins, including thyroid-binding globulin, transthyretin, and albumin. In patients with an intact hypothalamic-pituitary-thyroid axis, the thyroid gland compensates for urinary losses by increasing the production of T4. Consequently, despite heavy loss of proteins associated with the nephrotic syndrome, levels of biologically active free thyroid hormone are typically unaffected, and most patients with the nephrotic syndrome remain clinically euthyroid. However, patients who are reliant on a fixed exogenous source of T4 cannot compensate for the loss of T4, and thus, clinical hypothyroidism develops as a consequence of proteinuria. In patients who are dependent on exogenous thyroxine replacement, nephrotic-range proteinuria should prompt consideration of urinary loss of thyroid hormone.

Q: Describe some of the features of minimal-change disease.

A: Minimal-change disease is characterized clinically by nephrotic-range proteinuria and pathologically by diffuse effacement of epithelial foot processes on electron microscopy in the context of a relatively normal appearance on light microscopy. Although the disease has been reported after stem-cell transplantation, it is less common than membranous nephropathy in these patients. Glucocorticoids are the mainstay of drug therapy. Other immunomodulatory therapies, including calcineurin inhibitors, cytotoxic agents, rituximab, azathioprine, and mycophenolate mofetil, have been used in conjunction with low-dose glucocorticoids in patients who have unacceptable side effects with high-dose glucocorticoids or, more commonly, as glucocorticoid-sparing agents in relapsed disease. Adjunctive therapies for minimal-change disease typically include loop diuretics for edema, inhibitors of the renin-angiotensin-aldosterone system for hypertension and proteinuria, and 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (i.e., statins) for hyperlipidemia. Angiotensin-converting-enzyme inhibitors and angiotensin II receptor blockers improve the size selectivity of the glomerular barrier and may have long-term renal protective effects. Relapses are common in minimal-change disease despite therapy, and younger patients (<40 years of age) are more likely to have a relapse than older patients. A small case series suggested that up to a quarter of patients have three or more relapses per year.

Adverse Neuropsychiatric Effects of Glucocorticoids.

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Elevated incidence of suicide attempts, depression, mania, and delirium.

Glucocorticoids can have severe adverse neuropsychiatric effects, but the range and community-based population risk of such effects are unclear. In this U.K. study, researchers used a population-based general practice database to identify 370,000 patients with glucocorticoid exposure and compared them with 1.2 million patients with similar diseases (mostly asthma, lower respiratory tract infection, chronic obstructive pulmonary disease, and polymyalgia rheumatica) who had not taken glucocorticoids.

The overall incidence of any adverse neuropsychiatric effects that occurred within 3 months of a glucocorticoid prescription was 22.2 per 100 person-years of exposure. The incidence of adverse effects, adjusted for age, sex, and history of neuropsychiatric disorder, was roughly 3-fold higher for glucocorticoid recipients than for nonrecipients, ranging from roughly 4- to 6-fold higher for suicidal behavior, mania, and delirium or confusion, to about 1.5 times higher for panic disorder and depression. Incidence rose with history of neuropsychiatric disorder and with higher dosage of glucocorticoids, particularly at a prednisone equivalence of 40 mg daily.

Comment: Experienced clinicians often see these neuropsychiatric effects in patients who receive glucocorticoids for self-limited illnesses such as contact dermatitis; this study confirms such observations. Many potential confounders can affect a retrospective cohort study like this, including possible differences in patients with the seemingly same disease who are or are not prescribed glucocorticoids, but these results caution clinicians to consider these risks when prescribing glucocorticoids.

Source: Journal Watch General Medicine