Clinical trial NCT02378805: Alport Therapy Registry - European Initiative Towards Delaying Renal Failure in Alport Syndrome
Official title: European Alport Therapy Registry - European Initiative Towards Delaying Renal Failure in Alport Syndrome: Current and Novel Therapies
Study type: OBSERVATIONAL
Overall status: RECRUITING
Conditions: Alport Syndrome
Hereditary Kidney Disease
Pediatric Kidney Disease
Thin Basement Membrane Disease
Familial Benign Hematuria
Keywords: Alport syndrome
thin basement membrane disease
familial benign hematuria
Lead sponsor: University Hospital Goettingen
Sponsor class: OTHER
Collaborators: name: Society for Pediatric Nephrology (Germany)
First posted: 2015-03-04
Enrollment: 800
Sex: ALL
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: CROSS_SECTIONAL
Sampling method: PROBABILITY_SAMPLE
Study population: For Alport XXL, eligible patients were children or young adults with a definitive diagnosis of AS by genetic analysis or kidney biopsy and at early stages of AS (stages 0, I or II) at baseline.

AS stages were defined as:

Stage 0 Microhematuria without microalbuminuria Stage I Microalbuminuria: UACR 30-300 mg/gCreatinine Stage II Proteinuria: UACR \>300 with eGFR\>60 ml/min/1.73m2 Stage III eGFR\<60 ml/min/1.73m2 Stage IV end stage kidney failure Stage V death (from all causes)

Brief summary: The hereditary type IV collagen disease Alport syndrome leads to kidney failure early in life. Currently there are no specific medications approved for treatment, however, several therapies have been evaluated preclinically and could improve outcome. For that reason, this non-interventional, observational study investigates, if medications (1) delay disease progression; (2) delay time to kidney failure; (3) improve life-expectancy compared to untreated patients (relatives). This observational study started in 2006 as an European registry. Since 2019, this registry has been expanded to "Alport XXL" via the International Alport Alliance as a global effort across all continents. From 2020 on to present, "Alport XXL" has a special focus on the outcomes of early therapy in young patients on ACE-inhibitors vs. Angiotensin-receptor blockers vs. their combination.

Detailed description: Early diagnosis in children with Alport syndrome (AS) with isolated hematuria opens a "window of opportunity" for early intervention. In the Alport mouse-model, this early intervention with the ACE-inhibitor Ramipril let to a delay of kidney failure by 111%. In order to observe treatment approaches for AS in humans, this registry has been established in 2006 to collect data over several generations of Alport families across Europe. In the meantime, this registry has been expanded to "Alport XXL" via the International Alport Alliance as a global effort across all continents.

Small children with AS first develop microscopic hematuria (stage 0), proceeding to microalbuminuria (stage I), overt proteinuria (stage II), impaired kidney function (stage III) and finally can end up with kidney failure (stage IV), leading to impaired quality of life and premature death (stage V). This registry uses these stages to assess if earlier initiation of medications such as ACE-inhibition at earlier stages of disease is more effective than later therapy in delaying the time to disease progression (doubeling or tripeling of albuminuria), delaying loss of estimated glomerular filtration rate (eGFR), and if therapy improves life-expectancy.

Untreated children with autosomal-recessive AS, digenic AS, and boys with X-linked AS typically all develop kidney failure early in life. Untreated girls with X-linked AS have a 30-40% risk of kidney failure, typically later in life (40 years or older). Untreated heterozygous patients with COL4A3/COL4A4 variants typically have a less severe phenotype (in former times also called "familial benign hematuria" or "thin basement membrane nephropathy" (TBMN)) and a 1-2% risk of kidney failure.

Several interim results of this registry have been published since 2012.

Alport XXL is designed and conducted as strictly observational, non-interventional data acquisition with prospective (and in parts retrospective) data analysis. Young patients with AS in disease stages 0,I,II from all over the world are included. The renewed version from 2021 has been re-approved by the Ethics Committee of the University Medical Center Göttingen as "Alport XXL", a further development of the former European Alport Therapy Registry (AZ 10/11/06). "Alport XXL" registry and data storage are in conformity with Good Clinical Practice guidelines.

ICH-GCP-conform patient information and data exchange is secured by data transfer and cooperation agreements between all international trial centers and the coordinating principal investigator at University Medical Center Goettingen. At baseline, data collection including retrospective data is performed using a standardized, ICH-GCP-conform and pseudonymized questionnaire assessing age, sex, weight, height, mode of inheritance (X-linked, autosomal, compound heterozygous/homozygous, number of missense variants), family history, albumin in 24-hour or spontaneous urine, serum-creatinine, RAS-blockade with preparation and dose. Follow-up visits include same data than baseline plus blood-pressure, smoking-status, serum-potassium, eGFR, hearing loss and eye involvement, other symptoms such as leiomyomatosis, comorbidities and adverse events (adverse events of special interest defined as hyperkalemia, cough, hypotension, acute renal failure, malignancy, death).

Eligibility criteria: Inclusion Criteria:

Diagnosis of Alport syndrome (AS) by kidney biopsy or mutation analysis (or both).

Any type of genetic variant is accepted for X-linked, autosomal or digenic Alport syndrome (COL4A3, 4 or 5 genes).

Exclusion criteria:

Patients not willing to give informed consent. Patient with suspected diagnosis, whcih cannot be confirmed.

Primary outcomes:
measure: age at onset of end stage kidney failure (need for renal replacement therapy)
timeFrame: until end of observation in 2037
measure: life-expectancy in years (age at death)
timeFrame: until end of observation in 2037
measure: yearly loss of estimated glomerular filtration rate (eGFR)
timeFrame: until end of observation in 2037
measure: time in years until doubling or tripling of urinary albumin to creatinine ratio (UACR)
timeFrame: until end of observation in 2037
Secondary outcomes:
measure: amount of albuminuria over time
timeFrame: until end of observation in 2037
measure: amount of proteinuria over time
timeFrame: until end of observation in 2037
measure: number of patients with X-chromosomal or autosomal inheritance
timeFrame: until end of observation in 2037
measure: number of patients experiencing side effects (AEs)
timeFrame: until end of observation in 2037
measure: number of patients with hearing loss
timeFrame: until end of observation in 2037
measure: number of patients with eye involvement
timeFrame: until end of observation in 2037
measure: number of patients with positive family history of end stage kidney failure
timeFrame: until end of observation in 2037
measure: age of relatives at end stage kidney failure
timeFrame: until end of observation in 2037
Other outcomes:
Locations:
city: Göttingen
country: Germany
facility: University Medical Center Göttingen
state: Lower Saxony
Study officials:
affiliation: University Hospital Goettingen
name: Oliver Gross, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Kashtan CE, Gross O. Clinical practice recommendations for the diagnosis and management of Alport syndrome in children, adolescents, and young adults-an update for 2020. Pediatr Nephrol. 2021 Mar;36(3):711-719. doi: 10.1007/s00467-020-04819-6. Epub 2020 Nov 6.
citation: Weinstock BA, Feldman DL, Fornoni A, Gross O, Kashtan CE, Lagas S, Lennon R, Miner JH, Rheault MN, Simon JF; Workshop Participants. Clinical trial recommendations for potential Alport syndrome therapies. Kidney Int. 2020 Jun;97(6):1109-1116. doi: 10.1016/j.kint.2020.02.029. Epub 2020 Apr 6.
citation: Temme J, Kramer A, Jager KJ, Lange K, Peters F, Muller GA, Kramar R, Heaf JG, Finne P, Palsson R, Reisaeter AV, Hoitsma AJ, Metcalfe W, Postorino M, Zurriaga O, Santos JP, Ravani P, Jarraya F, Verrina E, Dekker FW, Gross O. Outcomes of male patients with Alport syndrome undergoing renal replacement therapy. Clin J Am Soc Nephrol. 2012 Dec;7(12):1969-76. doi: 10.2215/CJN.02190312. Epub 2012 Sep 20.
citation: Temme J, Peters F, Lange K, Pirson Y, Heidet L, Torra R, Grunfeld JP, Weber M, Licht C, Muller GA, Gross O. Incidence of renal failure and nephroprotection by RAAS inhibition in heterozygous carriers of X-chromosomal and autosomal recessive Alport mutations. Kidney Int. 2012 Apr;81(8):779-83. doi: 10.1038/ki.2011.452. Epub 2012 Jan 11.
citation: Gross O, Licht C, Anders HJ, Hoppe B, Beck B, Tonshoff B, Hocker B, Wygoda S, Ehrich JH, Pape L, Konrad M, Rascher W, Dotsch J, Muller-Wiefel DE, Hoyer P; Study Group Members of the Gesellschaft fur Padiatrische Nephrologie; Knebelmann B, Pirson Y, Grunfeld JP, Niaudet P, Cochat P, Heidet L, Lebbah S, Torra R, Friede T, Lange K, Muller GA, Weber M. Early angiotensin-converting enzyme inhibition in Alport syndrome delays renal failure and improves life expectancy. Kidney Int. 2012 Mar;81(5):494-501. doi: 10.1038/ki.2011.407. Epub 2011 Dec 14.
citation: Stock J, Kuenanz J, Glonke N, Sonntag J, Frese J, Tonshoff B, Hocker B, Hoppe B, Feldkotter M, Pape L, Lerch C, Wygoda S, Weber M, Muller GA, Gross O. Prospective study on the potential of RAAS blockade to halt renal disease in Alport syndrome patients with heterozygous mutations. Pediatr Nephrol. 2017 Jan;32(1):131-137. doi: 10.1007/s00467-016-3452-z. Epub 2016 Jul 11.
citation: Frese J, Kettwig M, Zappel H, Hofer J, Grone HJ, Nagel M, Sunder-Plassmann G, Kain R, Neuweiler J, Gross O. Kidney Injury by Variants in the COL4A5 Gene Aggravated by Polymorphisms in Slit Diaphragm Genes Causes Focal Segmental Glomerulosclerosis. Int J Mol Sci. 2019 Jan 26;20(3):519. doi: 10.3390/ijms20030519.
citation: Boeckhaus J, Hoefele J, Riedhammer KM, Nagel M, Beck BB, Choi M, Gollasch M, Bergmann C, Sonntag JE, Troesch V, Stock J, Gross O. Lifelong effect of therapy in young patients with the COL4A5 Alport missense variant p.(Gly624Asp): a prospective cohort study. Nephrol Dial Transplant. 2022 Nov 23;37(12):2496-2504. doi: 10.1093/ndt/gfac006.
citation: Zhang Y, Bockhaus J, Wang F, Wang S, Rubel D, Gross O, Ding J. Genotype-phenotype correlations and nephroprotective effects of RAAS inhibition in patients with autosomal recessive Alport syndrome. Pediatr Nephrol. 2021 Sep;36(9):2719-2730. doi: 10.1007/s00467-021-05040-9. Epub 2021 Mar 27.
citation: Boeckhaus J, Gross O. Sodium-Glucose Cotransporter-2 Inhibitors in Patients with Hereditary Podocytopathies, Alport Syndrome, and FSGS: A Case Series to Better Plan a Large-Scale Study. Cells. 2021 Jul 18;10(7):1815. doi: 10.3390/cells10071815.
citation: Boeckhaus J, Gale DP, Simon J, Ding J, Zhang Y, Bergmann C, Turner AN, Hall M, Sayer JA, Srivastava S, Kang HG, Cerkauskaite-Kerpauskiene A, Gillion V, Claes KJ, Krueger B, de Fallois J, Walden U, Choi M, Schueler M, Mueller RU, Todorova P, Hohenstein B, Zeisberg M, Friede T, Knebelmann B, Halbritter J, Gross O. SGLT2-Inhibition in Patients With Alport Syndrome. Kidney Int Rep. 2024 Sep 24;9(12):3490-3500. doi: 10.1016/j.ekir.2024.09.014. eCollection 2024 Dec.