Oral Galactose in Children With Steroid Resistant Nephrotic Syndrome
Oral Galactose in Children With Steroid Resistant Nephrotic Syndrome
Focal Segmental Glomerulosclerosis (FSGS) is a devastating kidney disease which is difficult
 to treat and carries a poor prognosis, with 50% of affected children progressing to end stage
 renal disease (ESRD). The purpose of this study is to investigate oral galactose as a benign
 treatment for FSGS in children. The investigators hypothesize that galactose, a simple milk
 sugar thought to bind to the protein factor (FSPF) that causes FSGS thereby inactivating it
 and stopping it from damaging the kidney, resulting in a reduction in glomerular permeability
 to albumin and decrease in proteinuria in children with nephrotic syndrome secondary to FSGS.
RESEARCH PLAN

 A: Primary aims:

 1. Determine the effect of 4 months of oral galactose administration on the level of FSPF
 in children with steroid resistant FSGS

 2. Determine the effect of 4 months of oral galactose administration on the first morning
 urine protein to creatinine (urine protein: creatinine) ratio and serum albumin level in
 children with steroid resistant FSGS.

 B: Secondary aims:

 1. Determine the effect of 4 months of oral galactose administration on dose of
 immunosuppressive medication.

 2. Assess first morning urine protein: creatinine ratio, serum albumin level, and change in
 immunosuppression dose at 3 months after discontinuation of oral galactose therapy.

 B.Background and Significance

 Idiopathic nephrotic syndrome (NS) in children is most commonly due to minimal change
 nephrotic syndrome and can be successfully treated with steroid therapy. However 10-15% of
 children with nephrotic syndrome are diagnosed with FSGS, which is resistant to steroid
 therapy and many other immunosuppressive drugs, and is associated with poor outcome.
 Approximately 50% of patients with FSGS progress to ESRD within 5-10 years and in about 30%
 of children, FSGS can recur after transplantation.(1) African-American children are at
 significantly higher risk for FSGS.(2) Recent studies indicate that primary FSGS is a
 heterogeneous disorder caused by genetic mutations in nearly a third of cases and as yet
 undefined immunological defects in the remaining cases.(3) Immune mediated FSGS has been
 associated with a circulating permeability factor, which is thought to increase glomerular
 permeability to albumin, leading to proteinuria and contributes to sclerotic lesions in FSGS.
 Presence of the FSPF is defined as permeability activity >0.5. (4) Current therapies for FSGS
 include plasmapheresis and many immunosuppressive agents that include cyclosporine,
 tacrolimus, mycophenolate mofetil, rituximab, and drugs that decrease proteinuria such as
 angiotensin converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) with
 inconsistent outcome. Additionally, these drugs have long-term consequences of
 immunosuppression and some drugs such as cyclosporine and tacrolimus affect renal function
 adversely when used for prolonged periods of time. (5) There is an urgent need for
 investigating benign therapies such as galactose. If proven to be useful, it may present a
 safe alternative or an adjunct to currently available therapies.

 Preliminary Studies:

 1. In 2008, Savin et al. showed that galactose, a simple nontoxic sugar, binds with high
 affinity to the FSPF in vitro.(6) They also found that trace amounts of galactose (>10-12 M)
 inhibited glomerular permeability activity induced by FSPF in vitro. This series of in vitro
 experiments also demonstrated that the effect of FSPF activity in serum can be reversed by
 its incubation with galactose or alternatively by pre-incubation of glomeruli with galactose.
 Additionally, the authors describe significantly decreased permeability activity in vivo in a
 single patient with post-transplant FSGS in response to both IV and oral galactose. The FSPF
 activity in this patient decreased progressively during the 4 weeks of galactose ingestion
 (from 0.8 to 0.1), and persisted 4 weeks after discontinuation of oral galactose (0.2). The
 proposed mechanism for this action is that FSPF have galactose-binding sites which interact
 with galactose of the glomerular glycocalyx, activating signal transduction in podocytes.
 Introduction of free galactose may block the FSPF binding sites or alter the tertiary
 structure of the FSPF, thus inhibiting its activity.

 Despite the decrease in FSPF activity in this patient, proteinuria did not improve. The
 authors propose the lack of clinical response may be due to the advanced stage of kidney
 damage at the time of IV galactose therapy, and this patient was already on dialysis at the
 time of oral galactose administration.

 It would be important to study the introduction of galactose early in the course of FSGS to
 determine if it is effective in decreasing proteinuria and delaying the progression of FSGS.

 De Smet et al presented their experience with a case of 48-year old male, with nephrotic
 syndrome secondary to FSGS, treated with oral galactose at 10 gm BID for 6 months, at the
 annual meeting of American Society of Nephrology 2008 (ASN 08, TH-PO-955). Their patient had
 failed to respond to prednisone, cyclophosphamide, mycophenolate mofetil, cyclosporine and
 plasma exchanges. Prior to treatment, the FSPF was detected at 0.87 and urinary protein
 excretion was 4.3 gm/day. After treatment with galactose, the FSPF decreased to 0.09 and
 urinary protein excretion decreased to 0.56 gm/day. The success obtained in this case argues
 for trial in additional patients.

 Methods:

 1. Oral galactose therapy: After obtaining informed consent and assent FSPF will be
 obtained at a baseline to determine eligibility. Blood samples for FSPF will be
 collected in a "red-top" tube (without anti-coagulant), allowed to clot, then spin and
 separate. The serum will be shipped on ice for FSPF analysis to the laboratory of
 Virginia Savin, Medical College of Wisconsin, Milwaukee, WI. All other parameters
 (including weight, height, blood pressure, urinalysis, urine protein: creatinine ratio,
 serum albumin, creatinine, electrolytes, and glucose) will be collected at the same
 visit as part of standard of care. Female participants of child bearing age will be
 given a urine pregnancy test and excluded from the study if pregnant.

 Once patients are found to be eligible, oral galactose will be initiated at a dose of
 0.2gm/kg/dose BID to a maximum of 15 gm BID for a period of 4 months. The prescribed
 dose of galactose powder will be dispensed to subjects in packets, mixed with 4 ounces
 of water, and consumed orally. FSPF will be measured again at week 16. All the other
 parameters will be repeated at 4, 10 and 16 weeks after starting oral galactose. Oral
 galactose therapy will be stopped after 16 weeks. In order to determine the clinical
 significance of the galactose treatment, a set of clinical parameters (weight, height,
 blood pressure, urinalysis, first morning urine protein: creatinine ratio, serum
 albumin, creatinine, electrolytes, and glucose) will be obtained at 12 weeks after
 discontinuation of oral galactose. Measurement of adherence with galactose will be
 estimated by counting the number of galactose doses returned at each subsequent monthly
 visit. Patients will be considered adherent if they have taken >90% of the prescribed
 doses.

 2. Adjunct therapy of nephrotic syndrome: Each patient will remain on his or her baseline
 therapy immunosuppressive therapy with cyclosporine, tacrolimus or mycophenolate
 mofetil. Steroids dose will be tapered to 0.5mg/kg, to a maximum of 40 mg, every other
 day at the time of starting galactose. If patient achieves remission, as indicated by
 negative first morning urine for protein for 3 consecutive days, alternate day steroid
 therapy will be tapered by 0.12mg/kg/dose or by 10 mg/dose, once per week. If patient
 has sustained remission for 1 month, and is off prednisone, the dose of
 immunosuppressive drugs will be lowered by 25% per month until off. BP will be
 controlled to below 95th percentile for height. If patient is on ACE inhibitors or ARBs,
 the dose will stay unchanged during the duration of galactose administration unless
 patient is experiencing side effects of therapy. If additional therapies for control of
 hypertension are needed, they would be chosen from the antihypertensive drugs other than
 ACE inhibitors and ARBs. Diuretics will be prescribed as needed for the symptomatic
 relief of edema. Adjunct therapy medications described in this section are standard of
 care and are not for research purposes.

 Result analysis:

 Each patient will serve as its own control. Results will be considered clinically significant
 if the following criteria are met in response to oral galactose therapy at week 16 and if the
 reduction in urine protein: creatinine and the increase in serum albumin persist at 12 weeks
 after discontinuation of galactose.

 1. Reduction in FSPF to <0.5 or decrease in FSPF by > 0.3

 2. Decrease in first morning urine protein: creatinine ratio by 50%

 3. Increase in serum albumin by >1gm/dl

 4. Decrease in dose of prednisone or other immunosuppressive drugs by 25% Statistical
 Analysis The primary outcomes are the means of paired pre vs. post galactose treatment
 differences in FSPF, urine protein: creatinine ratio, serum albumin and dose of
 immunosuppressive drugs. We will use repeated measures ANCOVA models to estimate each
 primary outcome as the dependent variable while holding constant pre-treatment levels.
 Therefore, the independent variable will be the pre-treatment level of the corresponding
 dependent variable, The model will be used to estimate the mean difference +/- the 95%
 confidence interval (CI) corresponding to the mean level of the dependent variable at
 pre-treatment. We will consider the pre-post difference to be statistically significant
 if the 95% CI around the result fails to include 0 and to be clinically significant if
 it meets the criteria specified above.

 Adequacy of the Sample: We evaluated the effect size difference that could be detected with
 80% and 90% power in a pre-post treatment study of galactose involving 10 patients assessed
 pre-treatment and post-treatment. The correlation between measurements on the same person was
 assumed to be .7 and the two-tailed type 1 error was set at 0.05. The study will have better
 than 90% power to detect effect size differences of 0.6 sd and better than 80% power to
 detect effect size differences of 0.5 sd. These are considered to be moderate effect sizes.

 Research Facilities: The FS permeability factor will be tested in the laboratory of Virginia
 Savin MD (Center for Glomerular Pathophysiology, Medical College of Wisconsin, Milwaukee, WI)
 using previously described methods.(7)

 Risks and Side Effects:

 FSGS is a difficult to treat disease associated with poor outcomes, including progression to
 end stage renal disease. Galactose is a naturally occurring simple sugar and oral galactose
 supplementation has no known side risks or side effects in humans. Patients eligible for this
 study are those who have failed to respond to the current alternative treatments for FSGS,
 which include steroids and other immunosuppressive agents, such as cyclosporine, tacrolimus,
 mycophenolate mofetil, and rituximab. These alternative immunosuppressive treatments have
 many long term complications, some of which include stunted growth, nephrotoxicity,
 hyperlipidemia, and diabetes. There is an urgent need for investigating benign therapies such
 as galactose, which may present a safe alternative or an adjunct to current therapies.

 There are no known side effects of oral galactose supplementation and no reports of toxicity
 with chronic use in humans. The Certificate of Origin for the D-Galactose product from
 FerroPfanstiehl is included in the Appendix and certifies that the D-Galactose to be used in
 our study is safe for human consumption.

 D-Galactose is administered safely in diagnostic testing for both glycogen storage disease
 and cirrhotic liver disease (8) and as sonographic contrast agents, such as Levovist ®
 (Bayer). Galactose has also been successfully administered as a treatment in Fabry's disease.
 (9) In this case report, IV galactose infusions were administered at a dose of 1 g/kg every
 other day for 2 years during which time liver function tests remained normal. Possible
 associations between dairy intake and ovarian cancer has been investigated with inconclusive
 results. A 2006 pooled analysis of 12 cohort studies done by Harvard School of public health
 found no association of intake of dairy foods with ovarian cancer and a statistically
 insignificant increase in risk of ovarian cancer at intakes of lactose > 30 g/d. This study
 involved analyzing surveys of reported dairy intake, but did not account for the presence of
 other factors in milk, such as hormones, that could contribute to ovarian cancer risk (10).
 Another 2005 meta-analysis in the European Journal of Cancer Prevention found no association
 between milk/dairy products or galactose metabolism and ovarian cancer risk. (11) In addition
 to occurring naturally in milk, galactose has been approved by the FDA as a substance
 Generally Recognized as Safe (GRAS) as an ingredient in infant formula and other baby foods
 and pediatric nutrition supplements in the form of galacto-oligosaccharides (a compound made
 of 1 to 7 galactose molecules linked to a glucose molecule at the reducing end).
 (www.fda.gov/food/foodingredientspackaging/generallyrecognizedassafeGRAS/GRASListings/ucm1539
 10.htm)

 Benefits:

 FSGS is resistant to steroid therapy and many other immunosuppressive drugs, and is
 associated with poor outcome. Approximately 50% of patients with FSGS progress to ESRD within
 5-10 years and in about 30% of children, FSGS can recur after transplantation.(1) Given the
 devastating course of this disease and the benign nature of the proposed galactose treatment,
 the anticipated benefits far outweigh the risks. If effective, galactose supplementation
 could stop the progression of FSGS, limiting glomerular damage and preventing progression of
 the disease to ESRD. The potential benefit of preserving kidney function and preventing the
 need for dialysis or transplantation is significant for both participants in this study and
 for other children with FSGS who may benefit from galactose therapy in the future.
Inclusion Criteria:

 1. 2-21 years old

 2. Biopsy proven FSGS or minimal change with steroid resistance

 3. Presence of FSPF (defined as permeability activity >0.5)

 4. Presence of nephrotic range proteinuria (urine protein: creatinine ratio >2) at the
 time of enrollment.

 5. Persistent nephrotic range proteinuria despite being on stable immunosuppressive
 medications (cyclosporine, tacrolimus or mycophenolate mofetil) for at least 12 weeks
 and/or persistent nephrotic range proteinuria despite being on stable dose of
 angiotensin converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs)
 for 12 weeks.

 6. Stable serum creatinine (change of less than 0.3 mg/dl) in the prior 3 months.

 7. Schwartz estimated (e) glomerular filtration rate (GFR) >60ml/min/1.73m2

 Exclusion Criteria:

 1. Secondary FSGS

 2. Onset of nephrotic syndrome in infancy.

 3. Presence of acute renal failure (as defined by acute kidney injury criteria) at the
 time of enrollment. These children can be enrolled 1 month after resolution of acute
 renal failure (ARF).

 4. Decreasing renal function (persistent increase in serum creatinine of greater than 0.3
 mg/dl over baseline in the prior 3 months).

 5. Use of another investigational drug

 6. Pregnant or unable to comply with contraceptive measures in females of child bearing
 age

 7. eGFR < 60 ml/min per 1.73 m2

 8. Children with Galactosemia

 9. Children with type 1 or 2 diabetes