Sometimes reality surpasses imagination also thanks to the progress of modern medicine. Paul Edmonds, a patient from California, managed to simultaneously win two of the toughest battles a person can face: the one against HIV and the one against cancer. The key to his incredible recovery? A stem cell transplant that has made history, and has just been illustrated in the New England Journal of Medicine (I'll link it all here).
A revolutionary therapy
Five years ago, Edmonds received an allogeneic hematopoietic cell transplant, commonly called a stem cell transplant. This procedure is often a last resort for blood diseases such as leukemia, myeloma and lymphoma, where blood-forming stem cells in the patient's bone marrow are destroyed by radiation or chemotherapy.
Healthy stem cells from a donor with similar (but not identical) genes are transplanted into the patient, where they can begin producing cancer-free blood.
In Edmonds' case, the donated stem cells had an added bonus: a genetic mutation associated with HIV-1 resistance. Yes, because Edmonds had lived with HIV-1 for 31 years before the transplant.
A difficult past
“People were dying within a few years of being HIV positive,” Edmonds said, describing his experiences in San Francisco in the 80s. The diagnosis in 1988, with full-blown HIV and AIDS, was a death sentence for him. A sentence that was not carried out.
Edmonds surprisingly resisted for 9 years, then managed to access antiretroviral therapy in 1997. A therapy that, however, does not cure HIV: the DNA of the virus was always present in his immune cells in his blood. Until his cancer treatment. What happened then?
An unexpected turning point from stem cells
The stem cells Edmonds received in his transplant had two copies of a rare genetic mutation called CCR5 delta-32. It is rare because it makes people who have it resistant to HIV. Only about 1-2% of the population has this mutation, but a donor match has been found for Edmonds (how important it is to activate effective programs to collect and manage stem cell and bone marrow donors!).
HIV uses the CCR5 receptor to enter and attack the immune system, but the CCR5 mutation prevents the virus from entering through this route.
The transplant completely replaced Edmonds' bone marrow and blood stem cells with those of the donor, and since then, he has shown no signs of leukemia or HIV. He is one of only five people in the world to have ever gone into remission from HIV with this treatment.
From a desperate past to a hopeful future
After the transplant, the HIV DNA is gone. Edmonds, for the sake of science, agreed to stop his HIV treatment 25 months after the transplant: it would have led to a surge in HIV RNA in his blood if the virus was still present.
“At the time of this follow-up, the patient was free of HIV-1 infection for 35 months after discontinuation of antiretroviral therapy,” the doctors write.
This case demonstrated that elderly patients undergoing reduced-intensity hematopoietic cell transplantation for cancer treatment can be cured of HIV-1 infection.
Stem cells, not yet for everyone
Stem cell transplants carry substantial risks, so not all people living with HIV will be able to receive this treatment. It's still only viable for those with life-threatening blood cancer: sure, now the ability to cure HIV will be a huge bonus.
Jana Dickter, a member of the medical staff involved in Edmonds' case, hopes others can benefit from this two-in-one treatment in the future. “For those who would benefit from a stem cell transplant for their cancer, the idea that they could simultaneously go into remission from HIV is incredible,” she says.
Edmonds' is a personal miracle, but also a significant step forward in the fight against two of the most feared diseases in the world. His story makes us understand how far we have come and how much more we can do thanks to medical research.
