Safety, pharmacokinetics, and activity of ABX-EGF, a fully human anti-epidermal growth factor receptor monoclonal antibody in patients with metastatic renal cell cancer.

PURPOSE: To determine the antitumor activity of ABX-EGF, a fully human monoclonal antibody to the epidermal growth factor receptor (EGFr), in previously treated patients with metastatic renal cell carcinoma, and to characterize its toxicity, immunogenicity, pharmacokinetics, and pharmacodynamics. PATIENTS AND METHODS: The antitumor activity, as well as the toxicity, pharmacokinetics, pharmacodynamics, and immunogenicity of ABX-EGF, were assessed. RESULTS: Eighty-eight patients were treated with ABX-EGF doses of 1.0, 1.5, 2.0, or 2.5 mg/kg weekly with no loading dose. EGFr immunostaining was performed on 76 tumor biopsy specimens (86%), and 69 (91%) scored positive. Major responses occurred in three patients, and two patients had minor responses. Forty-four patients (50%) also had stable disease at their first 8-week assessment, and the median progression-free survival (PFS) was 100 days (95% CI, 58 to 140 days). Low hemoglobin and high alkaline phosphatase predicted for short PFS. The principal toxicity, an acneiform rash, occurred in 68%, 95%, 87%, and 100% of patients who received at least three doses of ABX-EGF at 1.0, 1.5, 2.0, and 2.5 mg/kg/wk, respectively. A trend indicated that the severity of the rash may relate to PFS. No human antihuman antibodies were detected. ABX-EGF pharmacokinetics fit a model that incorporated both linear and saturable EGFr-mediated clearance mechanisms, and interindividual variability was low. At 2.5 mg/kg/wk, ABX-EGF concentrations throughout treatment exceeded those estimated to saturate nonlinear clearance and inhibit xenograft growth by 90%. CONCLUSION: ABX-EGF was generally well tolerated. The objective response rate was low in previously treated patients with metastatic renal cell carcinoma. Although skin rash may be a pharmacodynamic marker of drug action, its potential as a surrogate marker of clinical benefit requires further evaluation.     

Upper Extremity Free Flap Transfers: An Analysis of the National Surgical Quality Improvement Program Database

Introduction  We evaluated the demographics, flap types, and 30-day complication, readmission, and reoperation rates for upper extremity free flap transfers within the National Surgical Quality Improvement Program (NSQIP) database. Materials and Methods  Upper extremity free flap transfer patients in the NSQIP from 2008 to 2016 were identified. Complications, reoperations, and readmissions were queried. Chi-squared tests evaluated differences in sex, race, and insurance. The types of procedures performed, complication frequencies, reoperation rates, and readmission rates were analyzed. Results  One-hundred-eleven patients were selected (mean: 36.8 years). Most common upper extremity free flaps were muscle/myocutaneous (45.9%) and other vascularized bone grafts with microanastomosis (27.9%). Thirty-day complications among all patients included superficial site infections (2.7%), intraoperative transfusions (7.2%), pneumonia (0.9%), and deep venous thrombosis (0.9%). Thirty-day reoperation and readmission rates were 4.5% and 3.6%, respectively. The mean time from discharge to readmission was 12.5 days. Conclusion  Upper extremity free flap transfers could be performed with a low rate of 30-day complications, reoperations, and readmissions.     

Temporal Dynamics of the Intestinal Microbiome Following Short-Term Dietary Restriction

Short-term dietary restriction has been proposed as an intriguing pre-operative conditioning strategy designed to attenuate the surgical stress response and improve outcomes. However, it is unclear how this nutritional intervention influences the microbiome, which is known to modulate the systemic condition. Healthy individuals were recruited to participate in a four-day, 70% protein-restricted, 30% calorie-restricted diet, and stool samples were collected at baseline, after the restricted diet, and after resuming normal food intake. Taxonomy and functional pathway analysis was performed via shotgun metagenomic sequencing, prevalence filtering, and differential abundance analysis. High prevalence species were altered by the dietary intervention but quickly returned to baseline after restarting a regular diet. Composition and functional changes after the restricted diet included the decreased relative abundance of commensal bacteria and a catabolic phenotype. Notable species changes included Faecalibacterium prausnitzii and Roseburia intestinalis, which are major butyrate producers within the colon and are characteristically decreased in many disease states. The macronutrient components of the diet might have influenced these changes. We conclude that short-term dietary restriction modulates the ecology of the gut microbiome, with this modulation being characterized by a relative dysbiosis.     

An indirect treatment comparison of the efficacy of patisiran and tafamidis for the treatment of hereditary transthyretin-mediated amyloidosis with polyneuropathy

Background: Hereditary transthyretin-mediated amyloidosis (hATTR amyloidosis) is a progressive, life-threatening disease. Until recently, tafamidis was the only approved pharmacotherapy. Patisiran significantly improved polyneuropathy and quality of life (QoL) in the phase III APOLLO trial. In the absence of direct comparisons, this analysis aimed to evaluate the comparative efficacy of tafamidis and patisiran in hATTR amyloidosis with polyneuropathy.

Research design and methods: Randomized controlled trial evidence for tafamidis was identified by systematic literature review. Indirect treatment comparisons were performed using the standard pairwise Bucher method for endpoints used in both APOLLO and the tafamidis Fx-005 trial: change from baseline in Neuropathy Impairment Score-lower limbs (NIS-LL), Norfolk QoL-Diabetic Neuropathy questionnaire (QoL-DN), NIS-LL response, and mBMI vs. placebo. Inter-trial population differences were assessed by sensitivity analysis.

Results: The base-case analysis (FAP Stage 1 APOLLO patients vs. intent-to-treat Fx-005 population) suggested patisiran had a greater treatment effect vs. tafamidis for all endpoints, with significant improvements in mean change in NIS-LL (–5.49) and QoL-DN (–13.10) from baseline to Month 18. Similar trends were observed in all sensitivity analyses.

Conclusions: In the absence of direct comparisons, this analysis suggests patisiran has a greater treatment effect than tafamidis in patients with hATTR amyloidosis with polyneuropathy.     

Supplementation with NAD+ and Its Precursors to Prevent Cognitive Decline across Disease Contexts

The preservation of cognitive ability by increasing nicotinamide adenine dinucleotide (NAD⁺) levels through supplementation with NAD⁺ precursors has been identified as a promising treatment strategy for a number of conditions; principally, age-related cognitive decline (including Alzheimer’s disease and vascular dementia), but also diabetes, stroke, and traumatic brain injury. Candidate factors have included NAD⁺ itself, its reduced form NADH, nicotinamide (NAM), nicotinamide mononucleotide (NMN), nicotinamide riboside (NR), and niacin (or nicotinic acid). This review summarises the research findings for each source of cognitive impairment for which NAD⁺ precursor supplementation has been investigated as a therapy. The findings are mostly positive but have been made primarily in animal models, with some reports of null or adverse effects. Given the increasing popularity and availability of these factors as nutritional supplements, further properly controlled clinical research is needed to provide definitive answers regarding this strategy’s likely impact on human cognitive health when used to address different sources of impairment.     

Provider perspectives on service delivery modifications to maintain access to HIV pre‐exposure prophylaxis during the COVID‐19 pandemic: qualitative results from a PrEP implementation project in Kenya

IntroductionHIV pre‐exposure prophylaxis (PrEP) is an essential prevention strategy being scaled up for priority populations in Kenya, including for HIV serodiscordant couples. The COVID‐19 pandemic posed challenges to PrEP rollout. We conducted a qualitative study of PrEP providers to understand how clinics adjusted PrEP delivery during the COVID‐19 pandemic.MethodsSince 2017, the Partners Scale‐Up Project has integrated PrEP into 25 HIV clinics in Central and Western Kenya. We conducted qualitative interviews with 40 purposively sampled clinic personnel. We interviewed personnel once during the first pandemic wave (May–Aug 2020) and again after some decline in COVID‐19 rates (Nov–Jan 2021). We analysed data using inductive memo‐writing and summarized data by themes along the PrEP delivery cascade, guided by the Framework for Reporting Adaptation and Modifications (FRAME).ResultsWe interviewed 27 clinical officers, five nurses, four health records and information officers, and four counsellors from Central (n = 20) and Western (n = 20) Kenya. About half (n = 19) were female, with a median age of 32 (IQR: 29–34) and 2.3 years of experience delivering PrEP (IQR: 2–3). All participants reported clinic changes in PrEP demand creation and service delivery during the pandemic. Modifications occurred during PrEP implementation and sustainment phases, were partly reactive to the pandemic and also facilitated by interim Ministry of Health guidance on PrEP delivery during COVID, and were made by PrEP delivery teams, clients and clinic managers. Commonly reported modifications included dispensing multiple‐month PrEP refills, intensifying phone‐based client engagement and collaborating with other HIV clinics to ensure that clients with prolonged stays in other regions could continue to access PrEP. Some clinics also adopted practices to streamline visits, such as within clinical‐room PrEP dispensing, pre‐packing PrEP and task‐shifting. Most providers liked these changes and hoped they would continue after the pandemic subsides.ConclusionsCOVID‐19 served as a catalyst for PrEP delivery innovations in Kenya. HIV clinics successfully and rapidly adapted their PrEP demand creation, refill and retention strategies to promote PrEP uptake and effective use. These modified implementation strategies highlight opportunities to streamline the delivery of PrEP, as well as other HIV and chronic care services, and strengthen engagement with populations post‐pandemic.     

Effect of variable annular reduction on functional tricuspid regurgitation and right ventricular dynamics in an ovine model of tachycardia-induced cardiomyopathy

ObjectiveTo investigate the effect of variable tricuspid annular reduction (TAR) on functional tricuspid regurgitation (FTR) and right ventricular (RV) dynamics in ovine tachycardia-induced cardiomyopathy.MethodsNine adult sheep underwent implantation of a pacemaker with an epicardial lead and were paced at 200 to 240 bpm until the development of biventricular dysfunction and functional TR was noted. During reoperation on cardiopulmonary bypass, 6 sonomicrometry crystals were placed around the tricuspid annulus (TA) and 14 were placed on the RV epicardium. Annuloplasty suture was placed around the TA and externalized to an epicardial tourniquet. After weaning from cardiopulmonary bypass, echocardiographic, hemodynamic, and sonomicrometry data were acquired at baseline and during 5 progressive TARs achieved with suture cinching. TA area and RV free wall strains and function were calculated from crystal coordinates.ResultsAfter pacing, changes in left ventricular (LV) ejection fraction and RV fractional area decreased significantly. Mean TA diameter increased from 25.1 ± 2.9 mm to 31.5 ± 3.3 mm (P = .005), and median TR (range, 0-3+) increased from 0 (0) to 3 (2) (P = .004). Progressive suture cinching reduced the TA area by 18 ± 6%, 38 ± 11%, 56 ± 10%, 67 ± 9%, and 76 ± 8%. Only aggressive annular reductions (67% and 76%) decreased TR significantly, but these were associated with deterioration of RV function and strain. A moderate annular reduction of 56% led to a substantial reduction of TR with little deleterious effect on regional RV function.ConclusionsA moderate TAR of approximately 50% may be most advantageous for correction of functional TR and simultaneous maintenance of regional RV performance. Additional subvalvular interventions may be needed to achieve complete valvular competence.     

Deletion of mouse Porcn blocks Wnt ligand secretion and reveals an ectodermal etiology of human focal dermal hypoplasia/Goltz syndrome

The Drosophila porcupine gene is required for secretion of wingless and other Wnt proteins, and sporadic mutations in its unique human ortholog, PORCN, cause a pleiotropic X-linked dominant disorder, focal dermal hypoplasia (FDH, also known as Goltz syndrome). We generated a conditional allele of the X-linked mouse Porcn gene and analyzed its requirement in Wnt signaling and embryonic development. We find that Porcn-deficient cells exhibit a cell-autonomous defect in Wnt ligand secretion but remain responsive to exogenous Wnts. Consistent with the female-specific inheritance pattern of FDH, Porcn hemizygous male embryos arrest during early embryogenesis and fail to generate mesoderm, a phenotype previously associated with loss of Wnt activity. Heterozygous Porcn mutant females exhibit a spectrum of limb, skin, and body patterning abnormalities resembling those observed in human patients with FDH. Many of these defects are recapitulated by ectoderm-specific deletion of Porcn, substantiating a long-standing hypothesis regarding the etiology of human FDH and extending previous studies that have focused on downstream elements of Wnt signaling, such as β-catenin. Conditional deletion of Porcn thus provides an experimental model of FDH, as well as a valuable tool to probe Wnt ligand function in vivo.