 Patients receive cyclophosphamide intravenously IV over 30 minutes on day 1, pegfilgrastim subcutaneously SC on day 2, and TLR8 agonist VTX-2337 SC on day -6 of course 1 only and on days 9 and 16. Patients achieving complete response CR, partial response PR, or stable disease SD may continue therapy every 21 days for 3 additional courses. Treatment may then continue in the absence of disease progression or unacceptable toxicity. 