Initial prednisolone dosing for the first relapse of steroid-sensitive nephrotic syndrome in Japanese children

Using Bayesian pre-trial simulations to optimize the design of adaptive clinical trials in childhood nephrotic syndrome

BACKGROUND

Randomized controlled trials (RCTs) are often infeasible in rare pediatric diseases. Adaptive trials can increase trial efficiency while maintaining scientific validity. Our aim was to determine the optimal design of a Bayesian adaptive RCT in childhood nephrotic syndrome using simulation.

METHODS

We used simulation to evaluate candidate Bayesian adaptive clinical trial designs for a planned non-inferiority RCT comparing low-dose vs. standard-dose steroids for childhood nephrotic syndrome relapses. Each design had a unique combination of adaptive settings (stopping thresholds, futility margin, initial recruitment, and interim analysis frequency). We simulated 10,000 RCTs for each design to estimate operating characteristics (power, type 1 error rate, and mean sample size). The best designs were tested under plausible RCT conditions (varying treatment effect, recruitment rate, and prior distributions).

RESULTS

We simulated 10,000 trials for each of 540 adaptive RCT designs with unique combinations of adaptation settings (5.4 million simulated trials). For the top three designs, we simulated another 10,000 trials under 40 different RCT conditions (1.2 million simulated trials). The optimal trial design was associated with the lowest mean sample size, smallest probability of an inconclusive trial, and a type 1 error rate < 5 %. Compared to a frequentist RCT, using this Bayesian adaptive design with an informative prior decreased sample size by 71 % (n = 198 vs. n = 682).

CONCLUSIONS

Bayesian trial simulation was used to optimize the design of an adaptive RCT in childhood nephrotic syndrome, lowering estimated sample size. Adaptive designs can reduce barriers to conducting RCTs in rare pediatric diseases.

[Clinical assessment of moderate-dose glucocorticoid in the treatment of recurrence of primary nephrotic syndrome in children: a prospective randomized controlled trial]

OBJECTIVES

To study the clinical effect and adverse drug reactions of different doses of glucocorticoid (GC) in the treatment of children with recurrence of steroid-sensitive nephrotic syndrome (SSNS).

METHODS

A total of 67 children who were hospitalized and diagnosed with SSNS recurrence in the Department of Nephrology, Children's Hospital, Capital Institute of Pediatrics, from November 2017 to December 2019 were enrolled. They were randomly divided into a moderate-dose GC group (32 children) and a full-dose GC group (35 children). The two groups were compared in terms of urinary protein clearance, recurrence rate within 6 months, and incidence rate of GC-associated adverse reactions.

RESULTS

There was no significant difference in the urinary protein clearance rate between the moderate-dose GC and full-dose GC groups (91% vs 94%, P>0.05). There was also no significant difference in the recurrence rate within 6 months between the two groups (41% vs 36%, P>0.05). At 6 months of follow-up, compared with the full-dose GC group, the moderate-dose GC group had a significantly lower cumulative dose of prednisone [(87±18) mg/kg vs (98±16) mg/kg, P=0.039] and a significantly lower proportion of children with an abnormal increase in body weight (6% vs 33%, P=0.045). The logistic regression analysis showed that prednisone dose ≥10 mg/alternate day at enrollment was a risk factor for recurrence within 6 months in children with SSNS (P=0.018).

CONCLUSIONS

For children with SSNS recurrence, moderate-dose GC has similar effects to full-dose GC in the remission induction rate and the recurrence rate within 6 months, with a lower cumulative dose and fewer GC-associated adverse reactions within 6 months than full-dose GC.

Optimizing the corticosteroid dose in steroid-sensitive nephrotic syndrome

The use of corticosteroids in the treatment of steroid-sensitive nephrotic (SSNS) syndrome in children has evolved surprisingly slowly since the ISKDC consensus over 50 years ago. From a move towards longer courses of corticosteroid to treat the first episode in the 1990s and 2000s, more recent large, well-designed randomized controlled trials (RCTs) have unequivocally shown no benefit from an extended course, although doubt remains whether this applies across all age groups. With regard to prevention of relapses, daily ultra-low-dose prednisolone has recently been shown to be more effective than low-dose alternate-day prednisolone. Daily low-dose prednisolone for a week at the time of acute viral infection seems to be effective in the prevention of relapses but the results of a larger RCT are awaited. Recently, corticosteroid dosing to treat relapses has been questioned, with data suggesting lower doses may be as effective. The need for large RCTs to address the question of whether corticosteroid doses can be reduced was the conclusion of the authors of the recent corticosteroid therapy for nephrotic syndrome in children Cochrane update. This review summarizes development in thinking on corticosteroid use in SSNS and makes suggestions for areas that merit further scrutiny.