Has a history or current evidence of any condition, therapy, or laboratory abnormality that might confound the results of the study, interfere with the patient’s participation for the full duration of the study, or is not in the best interest of the participant to participate, in the opinion of the treating investigator. This includes any serious, intercurrent, chronic, or acute illness, such as cardiac disease (New York Heart Association [NYHA] class III or IV), hepatic disease, or other illness considered by the investigator as an unwarranted high risk for investigational drug SELLAS Life Sciences Group Galinpepimut -S Protocol : SLS17 -201/MK3475 -770 Protocol v1.1 (Amendment 1.0) 12 April 2019 Page 128 treatment.20. Has a known psychiatric or substance abuse disorder that would interfere with the participant’s ability to co operate with the requirements of the study. Other Exclusions 21. Is pregnant or breastfeeding or expecting to conceive or father children within the projected duration of the study, starting with the screening visit through 30 days after the last dose of study treatment. 22. Has had an allogeneic tissue/solid organ transplant. 23. Has received transfusion of blood products (including platelets or red blood cells) or administration of colony stimulating factors ( excluding GM-CSF, but including G CSF or recombinant erythropoietin) within 4 weeks prior to first study treatment. 4.1.2.1.