N-Acetylcysteine in Biliary Atresia After Kasai Portoenterostomy
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|ClinicalTrials.gov Identifier: NCT03499249|
Recruitment Status : Active, not recruiting
First Posted : April 17, 2018
Last Update Posted : August 18, 2021
Biliary atresia (BA) is a devastating liver disease of infancy, characterized by bile duct obstruction leading to liver fibrosis, cirrhosis, and eventual need for transplantation in most cases. BA is treated with Kasai portoenterostomy (KP). KPs can achieve bile drainage and improve outcomes. However, even with standard evidence of "good bile flow," bile flow rarely normalizes completely and liver disease continues to progress.
In this study, the investigators test whether intravenous N-acetylcysteine (NAC) can improve bile flow after KP. The rationale is that NAC leads to synthesis of glutathione, which is a powerful stimulator of bile flow. The primary objective is to determine whether NAC normalizes total serum bile acid (TSBA) concentrations within 24 weeks of KP. Achieving normal TSBAs is uncommon with current standard-of-care, and is predicted to be associated with better long-term outcomes. The secondary objectives are to describe how other parameters commonly followed in BA change with NAC therapy, as well as report adverse events occurring with therapy and in the first two years of life. This study follows the "minimax" Phase 2 clinical trial design.
|Condition or disease||Intervention/treatment||Phase|
|Biliary Atresia||Drug: N-Acetyl cysteine||Phase 2|
Biliary atresia (BA) is a disease characterized by fibro-obliteration of extrahepatic bile ducts leading to impaired bile flow (Sokol et al., 2007). BA is treated with the Kasai portoenterostomy (KP), an operation which connects the liver directly to the intestine in attempt to relieve bile back-up and promote bile flow. KPs have variable success. KPs occasionally normalize bile flow and stop disease progression (Jimenez-Rivera et al., 2013). More commonly, however, bile flow never completely normalizes after KP. This can be detected by elevated total bilirubin (TB) or conjugated bilirubin (Bc) serum concentrations, or, when TB and Bc are normal, elevated total serum bile acids (TSBA) concentrations (Bezerra et al., 2014; Shneider et al., 2015; Venkat et al., 2014). Impaired flow leads to fibrosis, cirrhosis, and eventual need for liver transplantation. Given these uneven results, therapies are urgently needed to enhance the KP's success.
The investigators hypothesize that N-acetylcysteine (NAC) will improve outcomes after KP, because NAC is a precursor for the powerful choleretic molecule glutathione (Ballatori and Truong, 1989, 1992, Ballatori et al., 1986, 1989). The hypothesis assumes that better bile flow will lead to better outcomes. This is supported by previous reports demonstrating that good bile flow correlates with slower disease progression in BA. For example, a recent study showed infants with good bile flow after KP were significantly less likely to develop failure-to-thrive, ascites, hypoalbuminemia, or coagulopathy in the first two years of life (Shneider et al., 2015). Furthermore, these infants had significantly higher transplant-free survival in the same time period. In this study, TB <2.0 mg/dL within three months of KP was used as the marker for good bile flow.
NAC has a number of properties that make it an especially attractive potential therapeutic agent. First, glutathione creates an osmotic gradient in the bile duct lumen which drives one-third of total bile flow in humans (the other drivers are bile acids and secretin/bicarbonate) (Ballatori and Truong, 1989, 1992, Ballatori et al., 1986, 1989). Second, NAC is a Food and Drug Administration-approved therapy for another serious liver condition in neonates and children (acetaminophen overdose). It has also been used for other liver and non-liver indications in neonates, with few reported adverse events (Ahola et al., 2003; Flynn et al., 2003; Jenkins et al., 2016; Kortsalioudaki et al., 2008; Mager et al., 2008; Soghier and Brion, 2006; Squires et al., 2013; Wiest et al., 2014). Third, glutathione is an anti-oxidant, which could scavenge the free radicals contributing to cirrhosis. Preclinical studies are also promising, with glutathione's strong choleretic properties best established in rat flow studies and NAC's hepatoprotective effects documented in rescuing different mouse models of cholestasis (Ballatori et al., 1986; Galicia-Moreno et al., 2009, 2012; Tahan et al., 2007).
To test the hypotheses, the investigators will administer intravenous NAC continuously for seven days and determine the number of subjects with normal TSBAs (0-10 umol/L) within 24 weeks of KP. In addition, markers of BA progression, such as abnormal laboratory results, failure-to-thrive, and occurrence of complications related to chronic liver disease, will be described over the first two years of life. Finally, all adverse events occurring during NAC infusion and in the 21 days after its completion will be recorded. The study employs the two-stage "minimax" Phase 2 clinical trial design, a design commonly used in oncological trials to determine whether a particularly therapy has sufficient activity to warrant a larger Phase 3 trial (Simon, 1989). The two-stage "minimax" design offers two distinct advantages compared to other designs: (i) early termination if the drug is not efficacious; and (ii) small sample sizes, because historical controls rather than a separate control arm are used.
|Study Type :||Interventional (Clinical Trial)|
|Estimated Enrollment :||16 participants|
|Intervention Model:||Single Group Assignment|
|Intervention Model Description:||This is a Phase 2 clinical trial using the two-stage "minimax" design described by Simon (Simon, 1989). As a Phase 2 trial, the trial's objective is to determine whether NAC has sufficient biological activity as adjunctive therapy for BA to warrant further study. By choosing the two-stage "minimax" design, we gain two advantages: (i) early termination if the drug is not efficacious, and (ii) using historical controls and therefore an overall smaller sample size to test the hypothesis, i.e., no randomization or control arm. This study design only identifies large effects (response >20%). For BA this is appropriate, because the field is in need of a robust therapy that can substantially limit liver damage and delay/prevent need for liver transplantation.|
|Masking:||None (Open Label)|
|Official Title:||A Phase 2 Trial of N-Acetylcysteine in Biliary Atresia After Kasai Portoenterostomy|
|Actual Study Start Date :||May 18, 2018|
|Estimated Primary Completion Date :||October 31, 2022|
|Estimated Study Completion Date :||October 31, 2023|
Experimental: N-Acetylcysteine Treatment
Will receive continuous intravenous NAC therapy (6.25 mg/kg/hour of 10 mg/ml solution, or 0.625 ml/kg/hour, to give 150 mg/kg/day), starting within 24 hours of completion of KP and lasting for a total of 7 days
Drug: N-Acetyl cysteine
Intravenous NAC therapy (6.25 mg/kg/hour of 10 mg/ml solution, or 0.625 ml/kg/hour, to give 150 mg/kg/day), starting within 24 hours of completion of KP and lasting for a total of 7 days
- Total serum bile acids [ Time Frame: Within 24 weeks after KP ]Total serum bile acids (TSBAs) within 24 weeks after Kasai portoenterostomy (KP) for biliary atresia (BA)
- Laboratory Markers [ Time Frame: First two years of life ]Laboratory markers for liver disease progression in the first two years of life, including conjugated bilirubin (Bc), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (GGT), albumin, sodium, total bilirubin (TB), platelets, international normalized ratio (INR), 25-hydroxy Vitamin D, Vitamin A, and Vitamin E
- Weight [ Time Frame: First two years of life ]Weight measurements in the first two years of life
- Sentinel Events [ Time Frame: First two years of life ]Occurrence of sentinel events related to worsening liver disease (cholangitis, development of ascites, variceal bleed, liver transplant listing, liver transplant, death) in the first two years of life
- Adverse Events [ Time Frame: Within four weeks after KP ]Adverse events possibly related to NAC, including rash, urticaria, pruritus, tachycardia, hypotension, vomiting, edema, anaphylaxis, and intravenous line issues
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03499249
|United States, Texas|
|Texas Children's Hospital and Baylor College of Medicine|
|Houston, Texas, United States, 77030|
|Principal Investigator:||Sanjiv Harpavat, MD. PhD||Baylor College of Medicine|