• The severity and incidence of thrombocytopenia as determined by the number of patient chemotherapy cycles during which the platelet count measures below 50,000/mm3 (NCI Grade 3 and/or 4 thrombocytopenia). [ Time Frame: During a maximum of six 3-week chemotherapy cycles ] [ Designated as safety issue: No ]
  

• The severity and incidence of thrombocytopenia as determined by the number of patients who experience a platelet count below 50,000/mm3 (NCI Grade 3 and/or 4 thrombocytopenia). [ Time Frame: During a maximum of six 3-week chemotherapy cycles ] [ Designated as safety issue: No ]
  
• The severity and incidence of thrombocytopenia as determined by absolute nadir and time to recovery of platelet count for each treatment cycle and study subject. [ Time Frame: During a maximum of six 3-week chemotherapy cycles ] [ Designated as safety issue: No ]
  
• The frequency and severity of Serious Adverse Events [ Time Frame: During a maximum of six 3-week chemotherapy cycles ] [ Designated as safety issue: Yes ]
  
• The incidence and grade of toxicity experienced by each dose group, changes in biochemistry, hematology, urinalysis, physical findings, and adverse events [ Time Frame: During a maximum of six 3-week chemotherapy cycles ] [ Designated as safety issue: Yes ]
  

This is a Phase IIb, multicenter, randomized, double-blind, placebo-controlled study comparing safety and efficacy of two dose levels of TXA127 when administered during 6 cycles of combination gemcitabine and platinum-based chemotherapy. This study intends to investigate the effectiveness of TXA127 for the mitigation of severity and/or incidence of thrombocytopenia, as well as safety when administered as a self-injected, subcutaneous solution.

Females 18 years of age or older with a confirmed diagnosis of ovarian carcinoma who are scheduled to undergo combination chemotherapy with gemcitabine and carboplatin or gemcitabine and cisplatin will be considered for this study. Subjects may be chemotherapy naïve, newly diagnosed, or post a single course of chemotherapy followed by a progression- and treatment-free interval of at least 3 months, or post 2 or more previous courses of chemotherapy after a progression- and treatment-free interval of at least 6 months.

Subjects will be randomized in a 1:1:1 ratio to one of the following three blinded treatment groups: placebo, 100 ug/kg/day TXA127 and 300 ug/kg/day TXA127.

Treatment will be concurrent with up to six consecutive 21-day cycles of one of the following gemcitabine and platin regimens:

Regimen A

• Intravenous cisplatin therapy at a dose of 30-50 mg/m2 given on Day 1 of the cycle
• Intravenous gemcitabine at a dose of 800 mg/m2 given on Day 1 after cisplatin and on Day 8 of the cycle.

Regimen B

• Intravenous gemcitabine at a dose of 1000 mg/m2 given on Days 1 and 8 of the cycle
• Intravenous carboplatin AUC 4 given after gemcitabine on Day 1 of the cycle

TXA127 will be self-administered as a subcutaneous injection by the subject once daily on Days 2-6 and 9-15 during each cycle of chemotherapy. Blood specimens will be drawn for hematologic analysis on Days 1, 8 and 15 of each treatment cycle.