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Constellation Pharmaceuticals


In July 2012, LLS began its partnership with Constellation to support three first-in-human Phase 1 clinical trials for blood cancer patients and the partnership lead to the ongoing trial "A Phase 3, Randomized, Double-blind, Active-Control Study of CPI-0610 and Ruxolitinib vs. Placebo and Ruxolitinib in JAKi Treatment Naive MF Patients."

Constellation Pharmaceuticals was a clinical-stage biopharmaceutical company developing novel therapeutics that selectively modulate gene expression to address serious unmet medical needs in patients with cancer. Constellation developed pelabresib (CPI-0610) which inhibits members of the BET family of chromosome-binding proteins to selectively inactivate various cancer-promoting genes, including MYC, a master control gene that plays a role in many cancers. Constellation was driving clinical development of pelabresib for the treatment of myelofibrosis in a Phase 2 clinical study (MANIFEST, NCT02158858). MorphoSys then acquired Constellation in July 2021 and continues to enroll patients with myeloproliferative neoplasms.

MorphoSys recently completed enrollment of myelofibrosis patients in a Phase 3 clinical trial (MANIFEST-2) of the BET inhibitor pelabresib (NCT04603495). Topline data is expected by the end of 2023.

For more information about MorphoSys, visit

Recent News

  • April 4, 2023 - announced that enrollment is complete for MANIFEST-2, the ongoing Phase 3 study with topline data expected by the end of 2023, earlier than previously anticipated.
  • December 11, 2022 - announced results from analyses of the ongoing MANIFEST study, an open-label Phase 2 clinical trial of pelabresib, an investigational BET inhibitor, in patients with myelofibrosis, a type of bone marrow cancer with limited treatment options. The latest analyses include longer-term data showing durable improvements in both spleen volume and symptom score beyond 24 weeks with pelabresib plus ruxolitinib in JAK inhibitor-naïve patients. The findings were presented during two oral sessions at the 64th American Society of Hematology (ASH 2022) Annual Meeting and Exposition in New Orleans, Louisiana.
  • December 12, 2021 - presented the latest data from the ongoing MANIFEST study, an open-label, Phase 2 clinical trial of pelabresib, an investigational BET inhibitor, in patients with myelofibrosis, a rare bone marrow cancer for which only limited treatment options are available. These latest results, which included more patients and longer-term follow-up than previously reported data, suggest the potential of pelabresib in the treatment of myelofibrosis. These findings were presented during poster and oral sessions at the 63rd American Society of Hematology Annual Meeting and Exposition (ASH 2021), held December 11 - 14, 2021 in Atlanta, Georgia and virtually.
  • July 15, 2021 - MorphoSys announced the successful completion of its previously announced cash tender offer for all outstanding shares of Constellation Pharmaceuticals, Inc. for a total equity value of the transaction of approximately $1.7 billion. MorphoSys will promptly complete its acquisition of Constellation through a second step merger of MorphoSys Development Inc. with and into Constellation resulting in Constellation surviving as an indirect wholly owned subsidiary of MorphoSys.