A Phase Ib Trial of AVID200, a TGFβ 1/3 Trap, in Patients with Myelofibrosis.

Abstract

PURPOSE:

Myelofibrosis (MF) is a clonal myeloproliferative neoplasm characterized by systemic symptoms, cytopenias, organomegaly, and bone marrow fibrosis. JAK2 inhibitors afford symptom and spleen burden reduction but do not alter the disease course and frequently lead to thrombocytopenia. TGFβ, a pleiotropic cytokine elaborated by the MF clone, negatively regulates normal hematopoiesis, downregulates antitumor immunity, and promotes bone marrow fibrosis. Our group previously showed that AVID200, a potent and selective TGFβ 1/3 trap, reduced TGFβ1-induced proliferation of human mesenchymal stromal cells, phosphorylation of SMAD2, and collagen expression. Moreover, treatment of MF mononuclear cells with AVID200 led to increased numbers of progenitor cells (PC) with wild-type JAK2 rather than JAK2V617F.

PATIENTS AND METHODS:

We conducted an investigator-initiated, multicenter, phase Ib trial of AVID200 monotherapy in 21 patients with advanced MF.

RESULTS:

No dose-limiting toxicity was identified at the three dose levels tested, and grade 3/4 anemia and thrombocytopenia occurred in 28.6% and 19.0% of treated patients, respectively. After six cycles of therapy, two patients attained a clinical benefit by IWG-MRT criteria. Spleen and symptom benefits were observed across treatment cycles. Unlike other MF-directed therapies, increases in platelet counts were noted in 81% of treated patients with three patients achieving normalization. Treatment with AVID200 resulted in potent suppression of plasma TGFβ1 levels and pSMAD2 in MF cells.

CONCLUSIONS:

AVID200 is a well-tolerated, rational, therapeutic agent for the treatment of patients with MF and should be evaluated further in patients with thrombocytopenic MF in combination with agents that target aberrant MF intracellular signaling pathways.

• Authors: John Mascarenhas, Anna Rita Migliaccio, Heidi Kosiorek, Rupali Bhave, Jeanne Palmer, Andrew Kuykendall, Ruben Mesa, Raajit K Rampal, Aaron T Gerds, Abdulraheem Yacoub, Kristen Pettit, Moshe Talpaz, Rami Komrokji, Marina Kremyanskaya, Agapito Gonzalez, Frank Fabris, Kathryn Johnson, Mikaela Dougherty, Erin McGovern, Juan Arango Ossa, Dylan Domenico, Noushin Farnoud, Rona Singer Weinberg, Amy Kong, Vesna Najfeld, Alessandro Maria Vannucchi, Francesca Arciprete, Maria Zingariello, Mario Falchi, Mohamed E Salama, Carolyn Mead-Harvey, Amylou Dueck, Lilian Varricchio, Ronald Hoffman
• Journal: Clinical cancer research : an official journal of the American Association for Cancer Research (Clin Cancer Res) Vol. 29 Issue 18 Pg. 3622-3632 (09 15 2023) ISSN: 1557-3265 [Electronic] United States
• PMID: 37439808 (Publication Type: Clinical Trial, Phase I, Multicenter Study, Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: ©2023 The Authors; Published by the American Association for Cancer Research.

Chemical References

• Janus Kinase 2
• Cytokines
• Immunologic Factors

Topics

• Humans
• Primary Myelofibrosis (drug therapy, metabolism)
• Myeloproliferative Disorders
• Janus Kinase 2 (metabolism)
• Cytokines (therapeutic use)
• Immunologic Factors (therapeutic use)
• Thrombocytopenia (chemically induced)