Study TLK199.2107 was terminated for business reasons.

Study TLK199.2107 is a multicenter, single arm, open-label Phase 2 study of oral ezatiostat (Telintra®) in patients with lenalidomide (Revlimid®) refractory or resistant, red blood cell (RBC) transfusion-dependent, Low to Intermediate-1 IPSS risk, del5q Myelodysplastic Syndrome (MDS).

Study TLK199.2107 is a multicenter, single arm, open-label Phase 2 study of oral ezatiostat (Telintra®) in patients with lenalidomide (Revlimid®) refractory or resistant, red blood cell (RBC) transfusion-dependent, Low to Intermediate-1 IPSS risk, del5q Myelodysplastic Syndrome (MDS). Independence from red blood cell transfusions, improvement in the levels of red blood cells, white blood cells, and platelets, and the response of the bone marrow were evaluated. Patients received a starting dose of 2000 mg total daily dose in divided doses (1000 mg orally twice daily for three weeks (21 days) on therapy followed by a one-week (7 days) off therapy rest period in four-week (28 days) treatment cycles. Patients continued treatment until documentation of lack of MDS response, MDS progression, unacceptable toxicity, or patient withdrawal from the study.

Inclusion Criteria:

• Primary or de Novo MDS
• Low or Intermediate-1 IPSS risk MDS
• Deletion of the 5q chromosome [del(5q) MDS]
• Refractory or resistant to lenalidomide (Revlimid)
• ECOG performance score of 0 or 1
• Documentation of significant anemia with or without additional cytopenia
• Adequate kidney and liver function
• Patients must have discontinued hematopoietic growth factors at least 3 weeks prior to study entry

Exclusion Criteria:

• Prior allogenic bone marrow transplant for MDS
• Known sensitivity to ezatiostat (injection or oral tablets)
• Prior treatment with hypomethylating agent (HMA) (e.g., azacitadine, decitabine)
• History of MDS IPSS risk score of greater than 1.0
• Pregnant or lactating women
• Any severe concurrent disease, infection or comorbidity that, in the judgement of the investigator, would make the patient inappropriate for study entry
• Oral steroids greater than 10 mg per day. Exceptions: those prescribed for other conditions (such as new adrenal failure, asthma, arthritis) or brief steroid use (such as tapered dosing for an acute non-MDS condition)
• History of hepatitis B or C, or HIV