The aim of this study is to assess the efficacy and safety of betaine in reducing urine oxalate excretion of Type 1 Primary Hyperoxaluria (PHI) patients. Hypothesis: Betaine will effectively reduce urine oxalate excretion in Primary Hyperoxaluria Type I patients.

NCT00283387

Conditions

1. Hyperoxaluria

Interventions

1. Drug: Betaine
2. Drug: Placebo

MeSH:Hyperoxaluria, Primary

Exclusion Criteria: 1. Patients who are fully VB6 responsive (i.e., G170R homozygotes). --- G170R ---

Hyperoxaluria Hyperoxaluria, Primary Our prior genotyping results have shown an association between the G170R allele and the clinical response to VB6. --- G170R ---

Since VB6 is a safe and completely effective treatment for patients homozygous for G170R, we will not study betaine in this group. --- G170R ---

Instead, 20 participants older than 6 years of age who are G170R compound heterozygous, non-G170R missense or truncating sequence change homozygous or heterozygous, will be selected for enrollment. --- G170R ---

Instead, 20 participants older than 6 years of age who are G170R compound heterozygous, non-G170R missense or truncating sequence change homozygous or heterozygous, will be selected for enrollment. --- G170R --- --- G170R ---

Participants in whom VB6 provides a partial reduction in urine oxalate excretion (compound heterozygotes for the G170R mutation) will be maintained on a stable dose of VB6 (8 mg/kg/d) for two months before and throughout betaine treatment. --- G170R ---

This study will test the effectiveness of two medications: ACEI (angiotensin converting enzyme inhibitor)and ARB (angiotensin receptor blocker) in reducing the renal injury induced by hyperoxaluria in patients with Primary Hyperoxaluria. Hypothesis: Calcium oxalate crystal deposition in the kidney causes inflammation and resulting injury to kidney tissue. Angiotensin blockade will improve these changes, thus slowing the progression of renal insufficiency in patients with Primary Hyperoxaluria.

NCT00280215

Conditions

1. Hyperoxaluria

Interventions

1. Drug: ACEI / Angiotensin converting enzyme inhibitor
2. Drug: ARB /Angiotensin Receptor Blocker
3. Drug: Placebo

MeSH:Hyperoxaluria, Primary

Homozygosity for the G170R mutation of AGXT h. --- G170R ---