Dose Escalation Study of Gemcitabine and ON 01910.Na in Solid Tumors

Inclusion Criteria:

* Patients with histologically confirmed solid malignancy for which standard curative or palliative measures do not exist or are no longer effective; or patients with a clinical rationale for a gemcitabine-based therapy.
* The last radiotherapy/chemotherapy dose must have been given ≥4 weeks prior to study drug initiation; with any acute or chronic adverse events of prior radiotherapy or chemotherapy having resolved to \<Grade 2 as determined by CTCAE v3.0.
* Patients must have a life expectancy of at least 12 weeks and an ECOG performance status of \<1.
* Patients must be \>18 years of age.
* Patients must have evaluable disease, either with informative tumor markers, or with measurable disease on imaging, by RECIST (Response Evaluation Criteria in Solid Tumors) criteria (Appendix II).
* Patients must have adequate liver and renal function as defined by serum creatinine no greater than 2.0 times the institution's upper normal limits (or a 24 hour creatinine clearance of \>50 ml/min) and total bilirubin level no greater than 2.0 times the institution's upper normal limits and transaminase levels no higher than 3.0 times the institution's upper normal limits. (Note that patients with primary liver cancer or hepatic metastases may have a total bilirubin value of up to 1.5 mg/dl and transaminase levels of up to 5.0 times the limit of normal).
* Patients must have adequate bone marrow function as defined by a granulocyte count of \>1,500/mm3, platelet count of \>100,000/mm3, and hemoglobin \>9 g/dl.
* Patients at the expanded phase at the MTD must be willing and able to undergo blood sampling for pharmacokinetic studies in Course 1.
* For patients in the expanded phase at the MTD, tumor amenable to a single tumor biopsy, and willingness to undergo a baseline tumor biopsy.
* Patients must sign an informed consent form indicating that they are aware of the investigational nature of this study and in keeping with the policies of the institution.

Exclusion Criteria:

Patients will be excluded if:

* They have evidence of active heart disease including myocardial infarction within the previous 3 months; symptomatic coronary insufficiency or heart block; uncontrolled congestive heart failure; moderate or severe pulmonary dysfunction.
* They have an active infectious process.
* They have active central nervous system metastases.
* They have received prior radiotherapy administered to more than 30% of marrow-bearing bone mass.
* They have ascites requiring active medical management including paracentesis more than twice a month or hyponatremia (defined as serum sodium value of \<134 Meq/L).
* Women who are pregnant or lactating.
* Male patients with female sexual partners who are unwilling to follow the strict contraception requirements described in this protocol (see Section 5.4).
* Patients who have had major surgery without full recovery or major surgery within 3 weeks of ON 01910.Na treatment start.