A Phase I/II Study of GPH101 in Autologous CD34+ Hematopoietic Stem Cells to Convert HbS to HbA for Treating Severe Sickle Cell Disease

About the study

This study is a first-in-human, single-arm, open-label Phase I/II study of GPH101 in approximately 15 participants, diagnosed with severe Sickle Cell Disease. The primary objective is to evaluate safety of the treatment in this patient population, as well as preliminary efficacy and pharmacodynamic data.

Study point of contact

Allison Intondi, PhD
[email protected]


3 United States sites


12 Years - 40 Years


Phase 1/Phase 2

Study type






participation requirements

≥12 to ≤ 40 years
Severe disease, as defined by having experienced at least one of the following SCD-related events despite appropriate supportive care measures:
recurrent severe VOC (≥ 4 episodes in the preceding 2 years)
ACS (≥ 2 episodes in the prior 2 years with at least one episode in the past year)
Lansky/Karnofsky performance status of ≥ 80

participation restrictions

Available 10/10 HLA-matched sibling donor
Prior HSCT or gene therapy
Prior or current malignancy or myeloproliferative or a significant coagulation or immunodeficiency disorder
Clinically significant and active bacterial, viral, fungal or parasitic infection
Pregnancy or breastfeeding in a postpartum female
Presence of a chromosomal abnormality/mutation that may put the participant at an increased risk for MDS or AML per investigator’s judgment


  • Birmingham, Alabama, United States, University of Alabama at Birmingham
  • Palo Alto, California, United States, Lucile Packard Children's Hospital
  • Saint Louis, Missouri, United States, Washington University
Last updated 2022-06-22