Citations

AbstractThe Alzheimer's Association's Research Roundtable met in November 2017 to explore the new National Institute on Aging and the Alzheimer's Association Research Framework for Alzheimer's disease. The meeting allowed experts in the field from academia, industry, and government to provide perspectives on the new National Institute on Aging and the Alzheimer's Association Research Framework. This review will summarize the “A, T, N System” (Amyloid, Tau, and Neurodegeneration) using biomarkers and how this may be applied to clinical research and drug development. In addition, challenges and barriers to the potential adoption of this new framework will be discussed. Finally, future directions for research will be proposed.

Background Sex-based disparities in liver transplantation (LT) are incompletely understood. We assessed the role of height, Model for End-Stage Liver Disease (MELD), MELD-Na, and exception points in the disparate access to LT. Methods Adults waitlisted for LT at Organ Procurement and Transplantation Network between 2002 and 2013 were included. Covariates associated with likelihood of LT were analyzed by Cox proportional model. In a separate cohort of waitlisted adults with glomerular filtration rate measurement by iothalamate clearance (n = 611), we determined the number of creatinine-derived MELD points in men versus women, across all ranges of glomerular filtration rate. The impact of correcting the MELD score deficit in women on LT was modeled. Results Among 90 720 Organ Procurement and Transplantation Network registrants, women had higher mortality than men (4 years after listing: 22% vs 18%, P < 0.0001), and lower likelihood of LT (49% vs 58%, P < 0.0001); women were 20% less likely to be transplanted (hazard ratio, 0.80; 95% confidence interval, 0.78-0.81). Differences in height and MELD exception scores accounted for most of the LT deficit in women (hazard ratio, 0.91; 95% confidence interval, 0.89-0.94). Women received between 1 and 2.4 fewer creatinine-derived MELD points than men with similar renal dysfunction. MELD-Na worsened the gender disparity. Addition of 1 or 2 MELD points to women significantly impacted LT access. Conclusions Differences in height and MELD exception points explained most of the sex-based disparity in LT. Additionally, MELD score underestimated disease severity in women by up to 2.4 points and MELD Na exacerbated this disparity. The degree of underestimation based on MELD had significant impact on allocation.

AbstractEpidemiological, biological, and molecular data suggest links between endometriosis and endometrial cancer, with recent epidemiological studies providing evidence for an association between a previous diagnosis of endometriosis and risk of endometrial cancer. We used genetic data as an alternative approach to investigate shared biological etiology of these two diseases. Genetic correlation analysis of summary level statistics from genomewide association studies (GWAS) using LD Score regression revealed moderate but significant genetic correlation (rg = 0.23, P = 9.3 × 10−3), and SNP effect concordance analysis provided evidence for significant SNP pleiotropy (P = 6.0 × 10−3) and concordance in effect direction (P = 2.0 × 10−3) between the two diseases. Cross‐disease GWAS meta‐analysis highlighted 13 distinct loci associated at P ≤ 10−5 with both endometriosis and endometrial cancer, with one locus (SNP rs2475335) located within PTPRD associated at a genomewide significant level (P = 4.9 × 10−8, OR = 1.11, 95% CI = 1.07–1.15). PTPRD acts in the STAT3 pathway, which has been implicated in both endometriosis and endometrial cancer. This study demonstrates the value of cross‐disease genetic analysis to support epidemiological observations and to identify biological pathways of relevance to multiple diseases.

AbstractBackgroundVorinostat combined with retinoids produces additive antitumor effects in preclinical studies of neuroblastoma. Higher systemic exposures of vorinostat than achieved in pediatric phase I trials with continuous daily dosing are necessary for in vivo increased histone acetylation and cytotoxic activity. We conducted a phase I trial in children with relapsed/refractory neuroblastoma to determine the maximum tolerated dose (MTD) of vorinostat on an interrupted schedule, escalating beyond the previously identified pediatric MTD.MethodsIsotretinoin (cis‐13‐retinoic acid) 80 mg/m2/dose was administered by mouth twice daily on days 1–14 in combination with escalating doses of daily vorinostat up to 430 mg/m2/dose (days 1–4; 8–11) in each 28‐day cycle using the standard 3 + 3 design. Vorinostat pharmacokinetic testing and histone acetylation assays were performed.ResultsTwenty‐nine patients with refractory or relapsed neuroblastoma were enrolled and 28 were evaluable for dose escalation decisions. Median number of cycles completed was two (range 1–15); 11 patients received four or more cycles. Three patients experienced cycle 1 dose‐limiting toxicities. A total of 18 patients experienced grade 3/4 toxicities related to study therapy. The maximum intended dose of vorinostat (430 mg/m2/day, days 1–4; 8–11) was tolerable and led to increased histone acetylation in surrogate tissues when compared to lower doses of vorinostat (P = 0.009). No objective responses were seen.ConclusionsIncreased dose vorinostat (430 mg/m2/day) on an interrupted schedule is tolerable in combination with isotretinoin. This dose led to increased vorinostat exposures and demonstrated increased histone acetylation. Prolonged stable disease in patients with minimal residual disease warrants further investigation.

AbstractAtopic dermatitis is the most common chronic skin disease, and it primarily affects children. Although atopic dermatitis (AD) has the highest effect on burden of skin disease, no high‐level studies have defined optimal therapy for severe disease. Corticosteroids have been used to treat AD since the 1950s and remain the only systemic medication with Food and Drug Administration approval for this indication in children, despite published guidelines of care that recommend against this option. Several clinical trials with level 1 evidence have supported the use of topical treatments for mild to moderate atopic dermatitis in adults and children, but these trials have had little consistency in protocol design. Consensus recommendations will help standardize clinical development and trial design for children. The Food and Drug Administration issues guidance documents for industry as a source for “the Agency's current thinking on a particular subject.” Although they are nonbinding, industry considers these documents to be the standard for clinical development and trial design. Our consensus group is the first to specifically address clinical trial design in this population. We developed a draft guidance document for industry, Developing Drugs for Treatment of Atopic Dermatitis in Children (≥3 months to <18 years of age). This draft guidance has been submitted to the Food and Drug Administration based on a provision in the Federal Register (Good Guidance Practices).

Background: The American Academy of Pediatrics and the National Academy of Medicine recommend vitamin D supplementation for breastfeeding infants. However, compliance with this recommendation is poor. Maternal supplementation with vitamin D is a safe and effective alternative to achieving vitamin D sufficiency in breastfeeding infants, and mothers have indicated a preference for self-supplementation over infant supplementation. Research aim: We sought to explore Family Medicine clinicians’ knowledge, attitudes, and practices regarding vitamin D supplementation recommendations for breastfeeding dyads. Methods: Fifty-six Family Medicine clinicians (including faculty physicians, resident physicians, and nurse practitioners/physician assistants) completed an online, anonymous survey regarding their knowledge and practices concerning vitamin D supplementation for breastfeeding infants. Results: The vast majority of clinicians (92.9%) correctly identified the American Academy of Pediatrics’ 2008 recommended dose for vitamin D supplementation in breastfeeding infants and estimated recommending vitamin D supplementation of exclusively breastfeeding infants 70.1% of the time. If all options were equivalent, clinicians would prefer to offer maternal or infant supplementation (50%) or maternal supplementation (37.5%) over infant supplementation (12.5%). Most (69.6%) preferred daily over monthly supplementation regimens. Conclusion: Family Medicine clinicians are knowledgeable regarding current recommendations for vitamin D supplementation in breastfeeding infants. They are also open to recommending maternal supplementation or offering parents a choice of maternal or infant vitamin supplementation.

Background Endogenous oxalate synthesis contributes to calcium oxalate stone disease and is markedly increased in the inherited primary hyperoxaluria (PH) disorders. The incomplete knowledge regarding oxalate synthesis complicates discovery of new treatments. Hydroxyproline (Hyp) metabolism results in the formation of oxalate and glycolate. However, the relative contribution of Hyp metabolism to endogenous oxalate and glycolate synthesis is not known. Methods To define this contribution, we performed primed, continuous, intravenous infusions of the stable isotope [ 15 N, 13 C 5 ]-Hyp in nine healthy subjects and 19 individuals with PH and quantified the levels of urinary 13 C 2 -oxalate and 13 C 2 -glycolate formed using ion chromatography coupled to mass detection. Results The total urinary oxalate-to-creatinine ratio during the infusion was 73.1, 70.8, 47.0, and 10.6 mg oxalate/g creatinine in subjects with PH1, PH2, and PH3 and controls, respectively. Hyp metabolism accounted for 12.8, 32.9, and 14.8 mg oxalate/g creatinine in subjects with PH1, PH2, and PH3, respectively, compared with 1.6 mg oxalate/g creatinine in controls. The contribution of Hyp to urinary oxalate was 15% in controls and 18%, 47%, and 33% in subjects with PH1, PH2, and PH3, respectively. The contribution of Hyp to urinary glycolate was 57% in controls, 30% in subjects with PH1, and <13% in subjects with PH2 or PH3. Conclusions Hyp metabolism differs among PH types and is a major source of oxalate synthesis in individuals with PH2 and PH3. In patients with PH1, who have the highest urinary excretion of oxalate, the major sources of oxalate remain to be identified.

Primary biliary cholangitis (PBC) is a rare chronic cholestatic liver disease that may progress to biliary cirrhosis if left untreated. The first‐line therapy for PBC is ursodeoxycholic acid (UDCA). Unfortunately, 1 of 3 patients does not respond to UDCA. These patients are at risk for developing clinical events, including cirrhosis, complications of portal hypertension, hepatocellular carcinoma, liver transplant, or death. Recently, the U.S. Food and Drug Administration approved obeticholic acid to be used in certain patients with PBC. Off‐label therapies are also used, and several other therapies are currently under evaluation. Real‐world effectiveness of newly approved and off‐label therapies remains unknown. TARGET‐PBC is a 5‐year, longitudinal, observational study of patients with PBC that will evaluate the effectiveness of clinical practice interventions and provide practical information unobtainable in registration trials. Enrollment will take place at both academic and community sites. In addition to consenting to medical records review, participants will be asked to provide an annual blood sample and complete patient reported outcome surveys at predetermined intervals. Any available liver biopsies will be digitally preserved. Conclusion: Key study outcomes will be the evaluation of the safety and effectiveness of PBC interventions and the assessment of disease progression under real‐world conditions. (Hepatology Communications 2018;2:484‐491)

Objective: 1) Characterize corrective saccades (CS) in normal controls, and 2) examine the sensitivity of the video head impulse test (vHIT) for identifying vestibular loss using both gain and CS. Study Design: Prospective combined with retrospective review. Setting: Tertiary referral center. Patients: Seventy subjects with normal vestibular function served as controls (mean age, 44.1 yr; range, 10–78) and data from 49 patients with unilateral and bilateral vestibular loss was retrospectively reviewed (mean age, 50; range, 7–81). Intervention: vHIT; individual horizontal head impulses were then analyzed in MATLAB. Main Outcome Measures: Horizontal vHIT gain, CS peak velocity, frequency, and latency. Results: There was not an age effect for CS velocity or latency, and only a weak relationship between CS frequency and age in the control group. Gain and CS latency were the only parameters affected by impulse side, demonstrating higher gain and longer latency on the right. The group with vestibular loss had significantly lower mean vHIT gain, higher mean CS frequency, higher mean CS velocity, earlier CS latency, and smaller mean CS standard deviations of the latency compared with the control group. When all factors were analyzed separately by logistic regression, vHIT gain provided the best classification (83.8%), closely followed by CS frequency (83.1%). Using a two variable approach (both gain and CS frequency) yielded the best diagnostic accuracy (overall classification = 84.6%). Conclusions: Along with gain, incorporating CS frequency in interpreting vHIT improves diagnostic accuracy. A repeatable CS (>81.89%) and/or low gain (<0.78) indicate vestibular loss.