Oxabact[®] treatment combined with intensive dialysis lowers plasma oxalate and halts disease progression in a patient with severe infantile oxalosis

Stockholm – March 12, 2020. OxThera AB, a privately-held biopharmaceutical company dedicated to improving the lives of people with Primary Hyperoxaluria (PH), announces the publication of a case report in Pediatric Nephrology. The report summarizes data from a 22-month course of treatment with Oxabact in a female infant with Primary Hyperoxaluria type 1 (PH1) and severe infantile oxalosis on dialysis. The treatment reduced plasma oxalate levels and stabilized systemic oxalosis.

Infantile oxalosis, the most devastating form of primary hyperoxaluria type 1 (PH1), often leads to end-stage renal disease (ESRD) during the first weeks to months of life. In these patients, dialysis cannot sufficiently remove oxalate, thus plasma oxalate concentration increases markedly, inducing systemic oxalate crystal deposition, organ damage, and often premature death. The only curative treatment is a sequential or combined liver-kidney transplantation, which is particularly challenging in young children who are too small to be transplanted.

In the publication, authors from the Hannover Medical School and from the University of Bonn, both in Germany, report the outcome of the therapeutic use of OxThera’s drug candidate Oxabact (Oxalobacter formigenes) in a female infant with PH1 who exhibited severely elevated plasma oxalate levels, pronounced nephrocalcinosis, anuretic end-stage renal disease and retinal oxalate deposits. Following the diagnosis of PH1 at an age of 8 weeks, a combined regimen of daily peritoneal dialysis, daily pyridoxine treatment and hemodialysis (3 times a week) was unable to reduce the pronounced hyperoxalemia. After the addition of Oxabact therapy (at the age of 15 weeks) to the otherwise unchanged treatment regimen, free plasma oxalate levels first stabilized and subsequently declined from 130 µmol/L to around 80 µmol/L. Nephrocalcinosis and retinal deposits were stabilized.

Oxabact treatment was well-tolerated and no related adverse events were observed. At approximately two years of age, the child was able to attend kindergarten and to walk and speak at a level similar to healthy children of the same age. The child received successful combined liver-kidney transplantation at nearly 26 months of age (22 months after the initiation of Oxabact administration), with normal liver and kidney function within a few days following transplantation.

“These results suggest that Oxabact treatment may be an option for reduction of oxalosis in infantile patients with insufficient response to conservative treatments until combined liver-kidney transplantation can be performed”, said Prof. Lars Pape, Deputy Head of the Department of Pediatric Kidney, Liver and Metabolic Disease, at Hannover Medical School, and first author of the report.

A phase 3 study of Oxabact (OC5-DB-02) and a follow-up, extension study (OC5-OL-02) are currently ongoing in patients with PH Type I-, II- and III-patients with maintained renal function. Oxabact has received orphan drug designation in the US and the EU for the treatment of PH.


Publication Details

Journal: Pediatric Nephrology

Year: 2020, doi: https://doi.org/10.1007/s00467-019-04463-9

Title: Oxalobacter formigenes treatment combined with intensive dialysis lowers plasma oxalate and halts disease progression in a patient with severe infantile oxalosis

For further information, please contact:

Matthew Gantz, CEO
Phone: +14846803001
E-mail: matthew.gantz@oxthera.com

About Oxabact®

Oxabact is a bi-modal enteric biotherapy containing a lyophilized formulation of Oxalobacter formigenes, a non-pathogenic, oxalate-degrading commensal bacterium. Oxabact is administered orally as a coated capsule. By promoting active and passive secretion of oxalate from the plasma into the gut, Oxabact potentials elimination of oxalate via the gut, lowering the oxalate burden in the kidneys. 

About OxThera

OxThera AB is a Swedish biotech company developing a new treatment for primary hyperoxaluria - a rare genetic and devastating disease with fatal outcomes. Currently pharmaceutical treatment is not available and median age of death is 30, if patients are not transplanted. A phase 3 study of Oxthera's drug candidate Oxabact® is ongoing, and an application for registration is expected to be submitted in the second half of 2021. Oxabact® has received orphan drug status in the US and the EU. Oxabact has received orphan drug designation in the US and the EU for the treatment of PH.


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