Groundbreaking Stem Cell Study Ultimately Seeks a Cure for AIDS
June 20, 2017 | by Samantha Bonar
In the study, doctors at the City of Hope’s City of Hope Alpha Clinic harvest HIV patients’ own stem cells and attempt to genetically modify them so that they are able to block HIV from infecting CD4 T cells, the human’s natural defensive cells against infection.
The study is based on the famous case of Timothy Ray Brown, aka the “Berlin patient,” an HIV patient who had leukemia. Brown had two bone barrow transplants to treat his cancer using stem cells from a donor that had a known mutation of the CCR5 gene that prevents the HIV virus from entering CD4 cells — the cells that provide the body’s defense against diseases.
After Brown’s bone marrow transplant, the HIV virus was no longer detectable in his blood even though he was no longer taking anti-retroviral medication. He is the only HIV patient who is considered “cured.”
Because finding a donor who carries the mutation and is also a stem cell match for the patient is such a daunting challenge, City of Hope’s study seeks to find out if introducing a mimicked form of the CCR5 mutation will have the same effect. The hope is that the mutated cells will survive, persist and replicate in the body, safely forming protection against the HIV virus.
Employed by the AIDS Healthcare Foundation (AHF) as a patient retention specialist, Rojas is active as an advocate for HIV and AIDS patients. His job is to locate and re-engage patients living with HIV who were once in care but dropped out, linking them to services that will help reduce the barriers that keep them from being engaged with their health care.
In August 2014, he was diagnosed with an HIV-related cancer, Burkitt’s lymphoma, despite maintaining medication adherence that suppressed his viral load. A co-worker told him about this particular City of Hope study, which places ribonucleic acid (RNA) genes that fight HIV into the patient’s stem cells and uses a lentivirus that targets HIV directly and changes the CCR5 gene to block the virus’ typical infection pathway. Rojas reached out to City of Hope, which told him that once he had received treatment for his lymphoma and was in remission, he should contact them again about participating in the study.
After nearly a year and a half of treatments, including eight rounds of chemotherapy and 20 radiation treatments, Rojas received his remission diagnosis in December 2015. He immediately contacted City of Hope, which enrolled him in the study.
Rojas’ stem cells were harvested in May 2016. He received chemotherapy to create space in his bone marrow, and the genetically modified stem cells were infused back into his body in July 2016.
Between procedures, Rojas, a devoted cyclist, participated in the AIDS LifeCycle event, riding his bike 545 miles from San Francisco to L.A. to raise money for HIV and AIDS awareness and treatment. Now nearly a year post-transplant, he just finished his second AIDS LifeCycle, starting in San Francisco and ending at Fairfax High School in West Hollywood on June 10.
“Cancer treatments for me haven't felt as debilitating as what I'm used to seeing others go through, so I feel incredibly fortunate” he said. “The stem cell transplant was actually not as horrible as I thought it was going to be. Three days after my transplant, I did go against the recommendation of my doctors and nurses and did a short 30-mile bike ride. One month later, I even joined my brother on the Pacific Crest Trail for two days.”
The most difficult part of the whole procedure, he said, was “initially having to come back to the outpatient hospital daily to get labs done and waiting around for the results since it was an outpatient procedure.”
He has also been preparing to apply to nursing school after earning his B.A. in sociology from UCLA in December 2015. “Going through my own medical treatments and working in medical care coordination has motivated me to further my career in nursing,” he said. He was particularly motivated by City of Hope nurse Teresa Kim, R.N., M.S.N. “She has been such a supportive, insightful and inspiring person through this whole process, and makes me want to be a nurse like her,” he said.
Rojas, who returns to City of Hope every three months for follow-up tests, still doesn’t know if the procedure worked. “If the [genetically modified] cells are persisting in my body at the 12-month point, and my HIV viral load remains undetectable, only then will my care team consider interrupting my active HIV medication regimen to see if my viral load remains undetectable,” he said. “If my viral load begins to increase, then the procedure technically did not show enough efficacy. But thus far I think I'm proof that the procedure is at least safe, which, I think, was ultimately the goal of this study.
“Once someone is diagnosed as living with HIV/AIDS, they will always have that diagnosis. “That’s what we’re doing here, trying to search for a cure.”