title: A phase 2 consortium (P2C) trial of 3-aminopyridine-2-carboxaldehyde thiosemicarbazone (3-AP) for advanced adenocarcinoma of the pancreas.
abstract: 3-Aminopyridine-2-carboxaldehyde thiosemicarbazone (3-AP, Triapine) is a novel small molecule inhibitor of ribonucleotide reductase (RR) with clinical signs of activity in pancreatic cancer. Therefore, the Phase 2 Consortium (P2C) initiated a trial (two single stage studies with planned interim analysis) of 3-AP at 96 mg/m(2) intravenously days 1-4 and 15-18 of a 28-day cycle in both chemotherapy-naive and gemcitabine-refractory (GR) patients with advanced pancreatic cancer. The primary endpoint was survival at six months (chemotherapy-naive) and four months (GR). Secondary endpoints were toxicity, response, overall survival, time to progression and mechanistic studies. Fifteen patients were enrolled including one chemotherapy-naïve and 14 GR. The chemotherapy-naïve patient progressed during cycle 1 with grade 3 and 4 toxicities. Of 14 GR patients, seven received two cycles, six received one cycle and one received eight cycles. Progression precluded further treatment in 11 GR patients. Additionally, one died of an ileus in cycle 1 considered related to treatment and two stopped treatment due to toxicity. Five GR patients had grade 4 toxicities possibly related to 3-AP and six GR patients had grade 3 fatigue. Toxicities and lack of meaningful clinical benefit prompted early study closure. Four-month survival in GR patients was 21% (95% CI: 8-58%). Correlative studies confirmed that 3-AP increased the percentage of S-phase buccal mucosal cells, the presence of multidrug resistance gene polymorphisms appeared to predict leukopenia, and baseline pancreatic tumor RR M2 expression was low relative to other tumors treated with 3-AP. In conclusion, this regimen appears inactive against predominantly GR pancreatic cancer. RR M2 protein may not have a critical role in the malignant potential of pancreatic cancer.
authors.affiliation: University of Wisconsin Paul P. Carbone Comprehensive Cancer Center, 600 Highland Avenue, K4/528, Madison, WI 53792, USA.
authors.forename: Steven
authors.initials: S
authors.lastname: Attia
authors.forename: Jill
authors.initials: J
authors.lastname: Kolesar
authors.forename: Michelle R
authors.initials: MR
authors.lastname: Mahoney
authors.forename: Henry C
authors.initials: HC
authors.lastname: Pitot
authors.forename: Daniel
authors.initials: D
authors.lastname: Laheru
authors.forename: James
authors.initials: J
authors.lastname: Heun
authors.forename: Wei
authors.initials: W
authors.lastname: Huang
authors.forename: Jens
authors.initials: J
authors.lastname: Eickhoff
authors.forename: Charles
authors.initials: C
authors.lastname: Erlichman
authors.forename: Kyle D
authors.initials: KD
authors.lastname: Holen
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy*; D000368:Aged; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D003841:Deoxycytidine / Q000031:analogs & derivatives / Q000627:therapeutic use; D018450:Disease Progression; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D019450:Genes, MDR; D006801:Humans; D007970:Leukopenia / Q000139:chemically induced; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000187:drug effects / Q000378:metabolism; D010190:Pancreatic Neoplasms / Q000188:drug therapy*; D011110:Polymorphism, Genetic; D011725:Pyridines / Q000009:adverse effects / Q000627:therapeutic use*; D012262:Ribonucleoside Diphosphate Reductase / Q000235:genetics; D015996:Survival Rate; D013882:Thiosemicarbazones / Q000009:adverse effects / Q000627:therapeutic use*; D016896:Treatment Outcome; D000093542:Gemcitabine
chemical_list: D000970:Antineoplastic Agents; D011725:Pyridines; D013882:Thiosemicarbazones; D003841:Deoxycytidine; C078157:3-aminopyridine-2-carboxaldehyde thiosemicarbazone; C093713:ribonucleotide reductase M2; D012262:Ribonucleoside Diphosphate Reductase; D000093542:Gemcitabine