Inclusion Criteria:

          1. Age ≥18 years at the time of voluntarily signing an IRB/IEC-approved informed consent

          2. Diagnosis of Myeloproliferative Neoplasms (MPN) either de novo myelofibrosis according
             to current WHO criteria (PMF), secondary myelofibrosis (post-PV MF and post-ET MF)
             according to the IWG-MRT consensus terminology) (Appendix I)

          3. Anemia with hemoglobin level of <10 g/dl or transfusion-dependent anemia*

          4. Splenomegaly (>11 cm total diameter) and/or leukoerythroblastosis

          5. Adequate organ function, i.e. ALT and/or AST <3 x upper limit of normal (ULN), total
             bilirubin <3 x ULN, and serum creatinine <2 mg/dl

          6. Subject must be willing to receive transfusion of blood products

          7. ECOG performance status <3

          8. Females of childbearing potential (FCBP) must undergo repetitive pregnancy testing
             (serum or urine) and pregnancy results must be negative.**

          9. Reliable contraception should be maintained throughout the study and for 28 days after
             study treatment discontinuation*

         10. Unless practicing complete abstinence from heterosexual intercourse, sexually active
             FCBP must agree to use adequate contraceptive methods*

         11. Males (including those who have had a vasectomy) must use barrier contraception
             (condoms) when engaging in sexual activity with FCBP. Males must agree not to donate
             semen or sperm*

         12. All subjects must:

               -  understand that the investigational product could have a potential teratogenic
                  risk.

               -  be counseled about pregnancy precautions and risks of fetal exposure.

               -  agree to abstain from donating blood while taking investigational product.

               -  agree not to share study medication with another person and to return all unused
                  study drug to the investigator.

        Exclusion Criteria:

          1. Patients eligible for hematopoietic stem cell transplantation (suitable candidate and
             suitable donor is available)

          2. Patients with response to standard therapy as recommended by the Deutsche Gesellschaft
             für Hämatologie und Medizinische Onkologie (DGHO/Onkopedia)

          3. Pregnant or breast feeding females

          4. BCR/ABL-positivity

          5. Diagnosis of ET (according to WHO 2016 criteria)

          6. Diagnosis of PV (according to WHO 2016 criteria)

          7. >20% blasts in peripheral blood or bone marrow

          8. thrombocytopenia <100 /nl or transfusion-dependent thrombocytopenia

          9. neutropenia <0.5 /nl

         10. Known positive status for HIV, HBV or HCV

         11. Prior treatment with IMiDs (thalidomide, lenalidomide, pomalidomide) or with
             Interferon-alpha within a 3 month time period before Screening-phase

         12. Patient treatment with Ruxolitinib within a 14 days time period before Screening-phase

         13. History of thrombosis or pulmonary embolism within 6 months prior to study entry

         14. Peripheral neuropathy >grade 1 CTC

         15. No consent for registration, storage and processing of the individual
             disease-characteristics and course as well as information of the family physician
             about study participation.

         16. Presence of any medical/psychiatric condition or laboratory abnormalities which may
             limit full compliance with the study, increase the risk associated with study
             participation or study drug administration, or may interfere with the interpretation
             of study results and, in the judgment of the Investigator, would make the patient
             inappropriate for entry into this study

         17. Drug or alcohol abuse within the last 6 months

         18. History of malignancy except for i) adequately treated local basal cell or squamous
             cell carcinoma of the skin, ii) asymptomatic prostate cancer without known metastatic
             disease and with no requirement for therapy or requiring only hormonal therapy and
             with normal prostate-specific antigen for ≥ 1 year prior to randomization, or iii) any
             other cancer that has been in complete remission for ≥ 5 years

         19. Patients undergoing treatment with hematopoietic growth factor receptor agonists
             (i.e., erythropoietin [Epo], granulocyte colony stimulating factor (GCSF [Neupogen;
             Neulasta], romiplostim, eltrombopag) within a 4 weeks period prior to screening-phase.

         20. Patients receiving any medication listed in the Appendix V "Prohibited Medications"
             (within 7 days prior to the first dose of study drug).

         21. Patients with clinically significant bacterial, fungal, parasitic or viral infection
             which require therapy. Patients with acute bacterial infections requiring antibiotic
             use should delay screening/enrollment until the course of antibiotic therapy has been
             completed.

         22. Patients under ongoing treatment with another investigational medication or having
             been treated with an investigational medication within 28 days of screening.

         23. No consent for biobanking.