Inclusion Criteria:

1. Has read, understood and signed the informed consent form (ICF) approved by the Independent Review Board/Ethics Committee (IRB/EC);
2. Is between the ages of 18 and 75 years old, inclusive;
3. Has histologically or cytologically confirmed stage IIIB (malignant pericardial or pleural effusion) or stage IV non-small cell lung cancer;
4. Has non-squamous, non-small cell lung cancer
5. Has measurable disease, defined as at least one tumor that fulfills the criteria for a target lesion according to RECIST;
6. Has an ECOG performance status of 0 or 1;
7. Has a life expectancy of > 3 months;

8. Has adequate hematologic function as evidenced by:

   1. ANC ≥ 1,500/μL
   2. PLT ≥ 100,000/μL
   3. HGB ≥ 9 g/dL obtained within 1 week prior to the first dose of study medication;

9. Has adequate renal function as evidenced by:

   1. Serum creatinine ≤ 1.5 X the upper limit of normal (ULN) for the reference lab
   2. Urine dipstick for proteinuria of < 1+ (i.e., either 0 or trace) within 2 weeks of Day 1 If urine dipstick is ≥ 1+, then urine protein excretion must be ≤ 500 mg over a 24 hour collection obtained within 1 week prior to the first dose of study medication;

10. Has adequate hepatic function as evidenced by:

    1. Serum total bilirubin ≤ 1.0 mg/dL
    2. AST ≤ 2.5X ULN for the reference lab (≤ 5X ULN for subjects with known hepatic metastases)
    3. ALT ≤ 2.5X ULN for the reference lab (≤ 5X ULN for subjects with known hepatic metastases) obtained within 1 week prior to the first dose of study medication;

11. Has adequate coagulation function as evidenced by:

    1. INR ≤ 1.5
    2. PTT ≤ ULN for the reference lab obtained within 1 week prior to the first dose of study medication;
12. If a woman of childbearing potential or a fertile man (and his partners), must agree to use an effective form of contraception (hormonal contraceptive, double-barrier method or abstinence) during the study.

Exclusion Criteria:

1. Has received prior systemic chemotherapy at any time for lung cancer;
2. Has received previous radiation therapy to >30% of active bone marrow or any radiation therapy within 3 weeks of Day 1;
3. Has a known hypersensitivity to baker's yeast, or has an active yeast infection;
4. Has had previous exposure to Betafectin® or Imprime PGG;
5. Has an active infection;

6. Presents with any of the following medical diagnoses/conditions at the time of screening:

   1. Central nervous system (CNS) metastases
   2. Uncontrolled hypertension (>150/100 mmHg) or hypertension that requires > two agents for adequate control
   3. Peripheral neuropathy ≥ grade 2 from any cause
   4. Fever of >38.5° C within 3 days prior to screening or Day 1, initial dosing
   5. Known HIV/AIDs, Hepatitis B, Hepatitis C, connective tissue or autoimmune disease, or other clinical diagnosis, ongoing or intercurrent illness that in the physician's opinion could interfere with participation

7. Has a history of any of the following medical diagnoses/conditions:

   1. Arterial or venous thromboembolic or hemorrhagic disorders including stroke, transient ischemic attack or cerebral infarction
   2. Deep vein thrombosis within 1 year prior to screening
   3. Myocardial infarction or an unstable or uncontrolled disease or condition related to or impacting cardiac function (e.g., unstable angina, congestive heart failure) within the previous 6 months
   4. Second malignancy within the previous 5 years, other than basal cell carcinoma, cervical intra-epithelial neoplasia or curatively treated prostate cancer with a PSA of <2.0 ng/mL
8. Has a known hypersensitivity to bevacizumab, murine proteins, or any component of bevacizumab;
9. Has a know sensitivity to polyethoxylated castor oil;
10. Has previously received treatment with bevacizumab;
11. Has had surgery within 4 weeks of Day 1 or needle or open biopsy within 1 week of Day 1;
12. Has a non-healing wound or gastric ulcer;
13. Has a non-healed bone fracture;
14. Is receiving systemic anti-coagulation therapy (e.g., dipyridalmole (Persantine®), ticlopidine (Ticlid®), clopidogrel (Plavix®) and /or cilostazol (Pletal®);
15. Is receiving chronic daily treatment with aspirin (>100 mg/day) or other nonsteroidal anti-inflammatory agents known to inhibit platelet function within 1 week of Day 1;

16. Presents with any of the following medical diagnoses/conditions at the time of screening:

    a. Predominant squamous cell histology

17. Has a history of any of the following medical diagnoses/conditions:

    1. Hemoptysis (≥ ½ tsp red blood)
    2. Bleeding diathesis or coagulopathy
18. If female, is pregnant or breast-feeding;
19. Is receiving concurrent investigational therapy or has received investigational therapy within a period of 30 days prior to the first scheduled day of dosing (investigational therapy is defined as treatment for which there is currently no regulatory-authority-approved indication);
20. Has previously received an organ or progenitor/stem cell transplant.