The Use of Trifluoperazine in Transfusion Dependent DBA — DBA  

Diamond Blackfan Anemia Clinical Trial

Official title: Phase I/II, Open Label Study to Determine Safety of Trifluoperazine (TFP) in Adults With Red Blood Cell Transfusion-Dependent Diamond Blackfan Anemia

Status Terminated

Clinical Trial Summary

Diamond Blackfan anemia (DBA) is a rare inherited pure red cell aplasia. The two main non-stem cell transplant therapeutic options are corticosteroids and red blood cell (RBC) transfusions. About 80% of DBA patients initially respond to corticosteroids, however, half of the patients cannot continue due to side effects or loss of response. These patients are then typically dependent on RBC transfusions throughout life. Each of these treatments is fraught with many side effects and significant morbidity and mortality are potential consequences of hematopoietic stem cell transplantation (SCT). The majority of individuals with DBA have mutations in genes encoding structural proteins of the small or large ribosomal subunit leading to deficiency of the particular ribosomal protein (RP). Using the RP deficient zebrafish embryo model, high throughput drug screens have demonstrated a strong hematologic response to several calmodulin inhibitors. One of these chemicals is trifluoperazine (TFP). TFP treatment of a mouse model of DBA also increased the red blood cell count and the hemoglobin (Hb) levels in the mice. TFP is a FDA-approved typical antipsychotic agent that has been available since 1958 with a well-known safety profile. In the United States, TFP is approved for the short-term treatment of generalized non-psychotic anxiety; treatment or prevention of nausea and vomiting of various causes; and, management of psychotic disorders.

This study aims to determine the safety/tolerability of TFP in adult subjects with DBA. TFP's expected dose-limiting toxicity is primarily neurologic (extrapyramidal) when used long-term at typical anti-psychotic doses (range 10-50 mg daily). Non-neurologic adverse effects in subjects with DBA have not been investigated. We will perform a dose escalation study to define the safety and tolerability of lower doses of this agent in subjects with DBA. To mitigate the potential risks of administering TFP to this new population, we will (1) start dosing at dose levels well below those prescribed for psychosis, (2) dose escalate to a maximum of 10 mg daily (the lowest dose typically prescribed for psychosis), and (3) perform weekly safety monitoring. Given the positive signal in DBA animal models and the 60-year clinical experience with higher doses of TFP, this drug warrants a trial in humans to assess tolerability in DBA.

Clinical Trial Description

This is a dose escalation safety/tolerability study to evaluate the presence of TFP-related adverse events in DBA subjects, and to determine the maximum tolerated dose (MTD) of TFP in DBA.

If tolerated, this trial will support either a proof of concept trial of low-dose TFP in DBA, or the advancement of a chemically modified TFP-like drug (to alleviate the neurologic toxicity) for the treatment of DBA. ;

Related Conditions & MeSH terms

• Anemia
• Anemia, Diamond-Blackfan
• Diamond Blackfan Anemia
• Pure Red Cell Aplasia
• Red-Cell Aplasia, Pure

• NCT number: NCT03966053
• Study type: Interventional
• Source: Northwell Health
• Status: Terminated
• Phase: Phase 1/Phase 2
• Start date: September 13, 2019
• Completion date: October 13, 2021