TY - JOUR
T1 - A phase I trial of DFMO targeting polyamine addiction in patients with relapsed/refractory neuroblastoma
AU - Sholler, Giselle L.Saulnier
AU - Gerner, Eugene W.
AU - Bergendahl, Genevieve
AU - MacArthur, Robert B.
AU - VanderWerff, Alyssa
AU - Ashikaga, Takamaru
AU - Bond, Jeffrey P.
AU - Ferguson, William
AU - Roberts, William
AU - Wada, Randal K.
AU - Eslin, Don
AU - Kraveka, Jacqueline M.
AU - Kaplan, Joel
AU - Mitchell, Deanna
AU - Parikh, Nehal S.
AU - Neville, Kathleen
AU - Sender, Leonard
AU - Higgins, Timothy
AU - Kawakita, Masao
AU - Hiramatsu, Kyoko
AU - Moriya, Shunsuke
AU - Bachmann, André S.
N1 - Publisher Copyright:
© 2015 Saulnier Sholler et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
PY - 2015/5
Y1 - 2015/5
N2 - Background Neuroblastoma (NB) is the most common cancer in infancy and most frequent cause of death from extracranial solid tumors in children. Ornithine decarboxylase (ODC) expression is an independent indicator of poor prognosis in NB patients. This study investigated safety, response, pharmacokinetics, genetic and metabolic factors associated with ODC in a clinical trial of the ODC inhibitor difluoromethylornithine (DFMO) ± etoposide for patients with relapsed or refractory NB. Methods and Findings Twenty-one patients participated in a phase I study of daily oral DFMO alone for three weeks, followed by additional three-week cycles of DFMO plus daily oral etoposide. No dose limiting toxicities (DLTs) were identified in patients taking doses of DFMO between 500-1500 mg/m2 orally twice a day. DFMO pharmacokinetics, single nucleotide polymorphisms (SNPs) in the ODC gene and urinary levels of substrates for the tissue polyamine exporter were measured. Urinary polyamine levels varied among patients at baseline. Patients with the minor T-allele at rs2302616 of the ODC gene had higher baseline levels (p=0.02) of, and larger decreases in, total urinary polyamines during the first cycle of DFMO therapy (p=0.003) and had median progression free survival (PFS) that was over three times longer, compared to patients with the major G allele at this locus although this last result was not statistically significant (p=0.07). Six of 18 evaluable patients were progression free during the trial period with three patients continuing progression free at 663, 1559 and 1573 days after initiating treatment. Median progression-free survival was less among patients having increased urinary polyamines, especially diacetylspermine, although this result was not statistically significant (p=0.056). Conclusions DFMO doses of 500-1500mg/m2/day are safe and well tolerated in children with relapsed NB. Children with the minor T allele at rs2302616 of the ODC gene with relapsed or refractory NB had higher levels of urinary polyamine markers and responded better to therapy containing DFMO, compared to those with the major G allele at this locus. These findings suggest that this patient subset may display dependence on polyamines and be uniquely susceptible to therapies targeting this pathway. Trial Registration Clinicaltrials.gov NCT#01059071.
AB - Background Neuroblastoma (NB) is the most common cancer in infancy and most frequent cause of death from extracranial solid tumors in children. Ornithine decarboxylase (ODC) expression is an independent indicator of poor prognosis in NB patients. This study investigated safety, response, pharmacokinetics, genetic and metabolic factors associated with ODC in a clinical trial of the ODC inhibitor difluoromethylornithine (DFMO) ± etoposide for patients with relapsed or refractory NB. Methods and Findings Twenty-one patients participated in a phase I study of daily oral DFMO alone for three weeks, followed by additional three-week cycles of DFMO plus daily oral etoposide. No dose limiting toxicities (DLTs) were identified in patients taking doses of DFMO between 500-1500 mg/m2 orally twice a day. DFMO pharmacokinetics, single nucleotide polymorphisms (SNPs) in the ODC gene and urinary levels of substrates for the tissue polyamine exporter were measured. Urinary polyamine levels varied among patients at baseline. Patients with the minor T-allele at rs2302616 of the ODC gene had higher baseline levels (p=0.02) of, and larger decreases in, total urinary polyamines during the first cycle of DFMO therapy (p=0.003) and had median progression free survival (PFS) that was over three times longer, compared to patients with the major G allele at this locus although this last result was not statistically significant (p=0.07). Six of 18 evaluable patients were progression free during the trial period with three patients continuing progression free at 663, 1559 and 1573 days after initiating treatment. Median progression-free survival was less among patients having increased urinary polyamines, especially diacetylspermine, although this result was not statistically significant (p=0.056). Conclusions DFMO doses of 500-1500mg/m2/day are safe and well tolerated in children with relapsed NB. Children with the minor T allele at rs2302616 of the ODC gene with relapsed or refractory NB had higher levels of urinary polyamine markers and responded better to therapy containing DFMO, compared to those with the major G allele at this locus. These findings suggest that this patient subset may display dependence on polyamines and be uniquely susceptible to therapies targeting this pathway. Trial Registration Clinicaltrials.gov NCT#01059071.
UR - http://www.scopus.com/inward/record.url?scp=84955112641&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84955112641&partnerID=8YFLogxK
U2 - 10.1371/journal.pone.0127246
DO - 10.1371/journal.pone.0127246
M3 - Article
C2 - 26018967
AN - SCOPUS:84955112641
SN - 1932-6203
VL - 10
JO - PloS one
JF - PloS one
IS - 5
M1 - e0127246
ER -
