Bone Marrow Stem Cells in Clinical Trial for Retinal Diseases
April 11, 2013 – Researchers from the University of California, Davis (UC Davis), have launched a Phase I clinical trial of CD34+ bone marrow stem cells (BMSC) for people with retinal conditions that cause vision loss from ischemia, or loss of blood flow, and cell degeneration. Led by Dr. Susanna Park, the investigative team believes the cells may promote the healing and survival of affected retinal tissue.
Dr. Park became interested in using CD34+ BMSC for retinal conditions because they have shown promising results in clinical trials for ischemic cardiac disease. In addition to helping repair damaged arteries, they appear to help cardiac cells recover from heart attacks and minimize the effects of heart failure.
A benefit of CD34+ BMSC is their ability to naturally hone to the site of damage or degeneration. That’s because the damaged tissue releases factors which attract the cells. A UC Davis preclinical study in mice showed that when CD34+ cells were in injected into mice with retinal damage, they migrated to the affected tissue.
Because each clinical trial patient serves as his or her own donor of CD34+ BMSC, there is no risk of immune rejection or need for immunosuppression. The cells are obtained by inserting a needle into the patient’s hip bone. A special laboratory technique is used to isolate the CD34+ BMSC from the extracted cell sample. The stem cells are then injected into the patient’s eye.
Dr. Park’s study is enrolling people with retinal degenerative diseases, such as retinitis pigmentosa (RP), Stargardt disease and dry age-related macular degeneration (AMD). The trial will also include people with retinal ischemia caused by diabetic retinopathy and retinal vein occlusion.
While the primary goal of the study is to assess safety, the researchers are also observing the CD34+ BMSC’s affect on vision and retinal structure. Results from the Phase I study will determine if a Phase II trial is warranted — to further evaluate efficacy — and which conditions may be most amenable to this form of treatment.
“We are excited about this approach because it is simple, doable and relatively safe,” says Dr. Park. “So far, the treatment has been well-tolerated, and we have preliminary data from the macular degeneration patients suggesting that the cells are incorporating into the retina.” |
