#5036 THE OUTCOME OF LUMASIRAN TREATMENT IN 10 PAEDIATRIC PATIENTS WITH PRIMARY HYPEROXALURIA TYPE 1

Abstract Background and Aims In primary hyperoxaluria type 1 (PH 1) a rare enzymatic defect in the liver leads to hepatic overproduction of oxalate. The resulting can cause nephrocalcinosis, urolithiasis renal failure. Conservative treatment options such as hyperhydration, citrate pyridoxine aim slow progression disease with transplant currently being only curative treatment. Since November 2020 Lumasiran is approved for use patients PH 1. reduces oxalate production by RNA interference may hence reduce hyperoxaluria. To date there limited real world data available on effectiveness Lumasiran. Method This observational study looked at outcome 10 under age 18 years genetically confirmed end point was percentage reduction plasma two haemodialysis urinary excretion preserved function. Secondary points were change follow up time 6 months one patient 12 other nine patients. Results Four girls median start 5.25 (range 0.3-17.9 years). One showed decrease which allowed dialysis frequency from 5x/week 3x/week whilst patient's had be intensified due worsening systemic oxalosis. function 71% 10–91%) after 78% 61–86%) months. Two reached values specific normal range (Matos et al.). discontinued 4 8 another An improvement nephrocalcinosis seen three subjective urolithiasis. Renal improved slightly remained stable others. Injection site reactions observed side effects. Conclusion Our highlights heterogeneity response Despite promising regarding benefits 2 did not benefit injections. Hence, it imperative regularly re-evaluate during Ideally should entered into registry monitor effects this novel drug short- but also long term.