Glaxo Wellcome and its Affymax Research Institute disclosed their entrance into the thrombopoiesis race last week, publishing in Science the ability of a synthetic peptide to mimic the specificity and potency of the natural hormone thrombopoietin (TPO).

TPO acts to stimulate the proliferation and maturation of megakaryocytes, the precursor cells that give rise to platelets, boosting platelet counts. This function is the basis for developing TPO as a therapeutic in a number of indications, including peripheral blood progenitor cell (PBPC) transplantation and thrombocytopenia resulting from chemotherapy. TPO itself has suffered from slow clinical development, opening some room for the peptide mimic in these indications.