Drew Cutler

Multicenter Phase 2 Trial of Sirolimus for Tuberous Sclerosis: Kidney Angiomyolipomas and Other Tumors Regress and VEGF- D Levels Decrease

Background Tuberous sclerosis (TSC) related tumors are characterized by constitutively activated mTOR signaling due to mutations in TSC1 or TSC2. Methods We completed a phase 2 multicenter trial to evaluate the efficacy and tolerability of the mTOR inhibitor, sirolimus, for the treatment of kidney angiomyolipomas. Results 36 adults with TSC or TSC/LAM were enrolled and started on daily sirolimus. The overall response rate was 44.4% (95% confidence intervals [CI] 28 to 61); 16/36 had a partial response. The remainder had stable disease (47.2%, 17/36), or were unevaluable (8.3%, 3/36). The mean decrease in kidney tumor size (sum of the longest diameters [sum LD]) was 29.9% (95% CI, 22 to 37; n = 28 at week 52). Drug related grade 1–2 toxicities that occurred with a frequency of >20% included: stomatitis, hypertriglyceridemia, hypercholesterolemia, bone marrow suppression (anemia, mild neutropenia, leucopenia), proteinuria, and joint pain. There were three drug related grade 3 events: lymphopenia, headache, weight gain. Kidney angiomyolipomas regrew when sirolimus was discontinued but responses tended to persist if treatment was continued after week 52. We observed regression of brain tumors (SEGAs) in 7/11 cases (26% mean decrease in diameter), regression of liver angiomyolipomas in 4/5 cases (32.1% mean decrease in longest diameter), subjective improvement in facial angiofibromas in 57%, and stable lung function in women with TSC/LAM (n = 15). A correlative biomarker study showed that serum VEGF-D levels are elevated at baseline, decrease with sirolimus treatment, and correlate with kidney angiomyolipoma size (Spearman correlation coefficient 0.54, p = 0.001, at baseline). Conclusions Sirolimus treatment for 52 weeks induced regression of kidney angiomyolipomas, SEGAs, and liver angiomyolipomas. Serum VEGF-D may be a useful biomarker for monitoring kidney angiomyolipoma size. Future studies are needed to determine benefits and risks of longer duration treatment in adults and children with TSC. Trial Registration Clinicaltrials.gov NCT00126672

Developmental Outcomes After Pediatric Heart Transplantation

BACKGROUND Pediatric heart transplantation has now been successfully performed for more than 20 years. As survival rates have improved, more attention is now focused on long-term outcomes. METHODS This report reviews the literature on developmental outcomes after pediatric heart transplantation. RESULTS Pediatric patients undergoing heart transplantation generally can be expected to have developmental outcomes in the low-normal range, consistent with outcomes seen in other children with complex congenital heart disease requiring surgical intervention. When these children reach school age, or return to school, most can be expected to function reasonably well in mainstream school settings. A significant minority will require additional educational assistance. Approximately 10% will have significant neurologic impairment. In school, particular attention should be paid to evaluating the child for deficits in arithmetic and verbal skills. Performance may be better than predicted from IQ testing. Behavioral issues are common, with depression, concerns about social competence, and attention difficulties most frequently endorsed. This may pre-date transplantation in those who undergo transplantation during childhood and may improve with time. Parents more often report problem behaviors than teachers. Family resources and family coping skills are also strongly correlated with the childs emotions and coping skills. CONCLUSION The pediatric heart transplant recipients ability to transition from childhood into a happy and productive adult life can be significantly affected by his or her cognitive abilities, learning experiences, sense of self, and emotions. Attention to these factors is an important part of caring for these children.

Calcineurin inhibitor minimization using sirolimus leads to improved renal function in pediatric heart transplant recipients.

Chinnock TJ, Shankel T, Deming D, Cutler D, Sahney S, Fitts J, Chinnock RE. Calcineurin inhibitor minimization using sirolimus leads to improved renal function in pediatric heart transplant recipients.
Pediatr Transplantation 2011: 15: 746–749.

BK virus nephropathy in the native kidneys of a pediatric heart transplant recipient

Sahney S, Yorgin P, Zuppan C, Cutler D, Kambham N, Chinnock R. BK virus nephropathy in the native kidneys of a pediatric heart transplant recipient.
Pediatr Transplantation 2010:14:E11–E15.

Clinical outcome 10 years after infant heart transplantation

The feasibility of heart transplantation for infants has now been established. Clinical outcome data is necessary to assist in targeting areas for improvement and for counseling families considering this option. This report describes clinical outcome in 29 infant heart transplant recipients who have survived at least 10 years. A query of the transplant database, referring physicians and parental questionnaire was performed. Patient survival for the overall infant population is 64% at 13 years. Parents of 19/29 (55%) children described them as developmentally normal. Three children have had a severe developmental outcome. Sixteen of 29 children are in mainstream school environments. Four have repeated one grade in school. Speech delay was present in 10/26 (38%). Somatic growth is normal in 88%. All children are NYHA class I. Renal function shows only modest insufficiency with most recent BUN (mean+/-S.D.)=25+/-7 mg/dl and serum creatinine=0.8+/-0.2 mg/dl. Only four children have creatinine levels >1 mg/dl. No child requires dialysis. No children have developed post-transplant lymphoproliferative disease beyond 10 years. Four children have experienced rejection beyond 10 years with one mortality due to rejection and transplant coronary artery disease. Conclusion: Heart transplantation during infancy is technically feasible and results in good survival. Many children have some degree of learning disability but most are mild and the children function well in society. Improvements in surgical techniques may improve developmental outcome. Other side-effects of immunosuppression are manageable and most survivors have a good functional outcome.

Comparison of outcomes with low-dose anti-thymocyte globulin, basiliximab or no induction therapy in pediatric kidney transplant recipients: a retrospective study.

Abstract: It is unclear which induction therapy yields the best outcomes in pediatric kidney transplantation. Retrospective data of 88 children receiving a renal allograft between November 1996 and October 2003 were analyzed. Patients received ATGI (n = 12), BI (n = 29), or NAI (n = 47). The mean ATG dose was 5.1 ± 2.1 mg/kg. At 12 months, graft survival rates were 91.7%, 100%, and 97.9% for ATGI, BI, and NAI groups, respectively. Acute rejection rates at 12 months were 0 (ATGI), 20.6% (BI), and 10.7% (NAI). The mean GFR for ATGI (42.4 ± 25.9 mL/min) was lower than for BI (78.3 ± 27.2 mL/min), and NAI (66 ± 28.3 mL/min) at 12 months (p < 0.05). One ATGI patient developed CMV pneumonia but none developed post‐transplant lymphoproliferative disorder. Although there was no renal allograft survival benefit with either ATGI or BI, relative to NAI, the absence of acute rejection and equivalent rates of viral infections in the higher‐risk ATGI recipient group suggests that the treatment strategy is promising. A large prospective study is needed to better define the role of ATGI in pediatric kidney transplantation.

Nail-Patella Glomerulopathy Without Associated Constitutional Abnormalities

A 17-year-old boy presented with a history of longstanding hematuria and non-nephrotic proteinuria without renal insufficiency, for which renal biopsy was performed. The findings by routine light microscopy and direct immunofluorescence study were mild and nonspecific. Electron microscopy, however, demonstrated the unexpected finding of distinct collagen fibrils within capillary wall basement membranes, typical of the nail-patella syndrome. Repeat physical examination following the biopsy confirmed the presence of normal nails and patellae, and radiographs of the knees were also normal. The boys renal disease was stable at last follow-up. The authors briefly discuss the differential diagnosis, and suggest that this case represents an unusual manifestation of the nail-patella syndrome, in which the glomerular changes are present in the absence of the usual associated constitutional abnormalities.

Similar Trends in Serum VEGF-D Levels and Kidney Angiomyolipoma Responses with Longer Duration Sirolimus Treatment in Adults with Tuberous Sclerosis

Context We have previously shown that serum VEGF-D is elevated at baseline, correlates with kidney angiomyolipoma size at baseline and 12 months, and decreases with sirolimus treatment in adults with tuberous sclerosis complex (TSC). To further investigate the utility of serum VEGF-D for longer term monitoring of TSC kidney disease, we present VEGF-D level results with 24 month follow-up. Objective To compare 24 month VEGF-D levels in two subgroups of sirolimus treated patients (OFF SIROLIMUS AFTER 12 MONTHS or ON SIROLIMUS AFTER 12 MONTHS). Design and Intervention(s) Serum VEGF-D was measured in samples collected from subjects enrolled in a phase 2 multicenter trial evaluating sirolimus for the treatment of kidney angiomyolipomas associated with TSC or TSC/LAM. All participants were treated with sirolimus from 0–12 months. During months 12–24, sirolimus was discontinued in one subgroup. The other subgroup was treated with additional sirolimus. Setting Adult TSC participants were recruited from six clinical sites in the United States (comprehensive TSC clinics, 5; urology clinic, 1). Patients There were 28 TSC patients who completed all 24 months of the study and serum samples were available at 24 months from 18/28 patients. Main Outcome Measure(s) We compared the percent change in VEGF-D levels (baseline to 24 months) in patients from the two treatment subgroups. Results At 24 months, VEGF-D levels decreased by 67% compared with baseline (to 787±426 pg/ml) in the ON SIROLIMUS AFTER 12 MONTHS group versus a 13% decrease (to 2971±4014 pg/ml) in the OFF SIROLIMUS AFTER 12 MONTHS group (p = 0.013, Mann-Whitney test). A similar trend was observed in kidney angiomyolipoma size but not in pulmonary function tests. Conclusions Serum VEGF-D may be useful for monitoring response to treatment with sirolimus and kidney angiomyolipoma size in patients with TSC, but confirmation is needed. Trial Registration Clinical trials.gov NCT00126672.