Oral Ezatiostat HCl (TLK199) and Myelodysplastic syndrome: a case report of sustained hematologic response following an abbreviated exposure.

Abstract

Treatment options for patients with lower risk non-del(5q) myelodysplastic syndromes (MDS) who fail erythroid stimulating agents are restricted to one of the hypomethylating drugs with an expected response rate of approximately 50%. Ezatiostat HCl, an agent with the potential for producing multi-lineage responses in this population is currently in clinical investigation phase. This case report describes a 77 year old male who received less than two cycles of therapy with ezatiostat HCl which had to be aborted due to intolerable side effects, but which produced a sustained normalization of all three blood counts. This trilineage response has now lasted for more than a year. Interestingly, the patient began with a del(5q) abnormality and responded briefly to lenalidomide. Upon relapse of the anemia, a bone marrow showed the disappearance of the del(5q) but the appearance of a new clonal abnormality t(2;3). Given that the patient had a complete cytogenetic response to a truncated exposure to lenalidomide followed by a trilineage response to an even briefer course of ezatiostat HCl suggests a potential role for ezatiostat HCl in del(5q) patients who relapse following lenalidomide.

• Authors: Fahd Quddus, Jessica Clima, Helen Seedham, Ghulam Sajjad, Naomi Galili, Azra Raza
• Journal: Journal of hematology & oncology (J Hematol Oncol) Vol. 3 Pg. 16 (Apr 23 2010) ISSN: 1756-8722 [Electronic] England
• PMID: 20416051 (Publication Type: Case Reports, Journal Article)

Chemical References

• Antineoplastic Agents
• Hemoglobins
• gamma-Glu-S-BzCys-PhGly diethyl ester
• Thalidomide
• Lenalidomide
• Glutathione

Topics

• Administration, Oral
• Aged
• Antineoplastic Agents (therapeutic use)
• Chromosome Deletion
• Chromosomes, Human, Pair 2 (genetics)
• Chromosomes, Human, Pair 3 (genetics)
• Chromosomes, Human, Pair 5 (genetics)
• Erythroid Cells (drug effects)
• Glutathione (administration & dosage, analogs & derivatives)
• Hemoglobins (metabolism)
• Humans
• Lenalidomide
• Male
• Myelodysplastic Syndromes (drug therapy, genetics)
• Remission Induction
• Thalidomide (analogs & derivatives, therapeutic use)
• Treatment Outcome