The ‘Sao Paulo Patient’ restarts treatment as HIV returns
A patient from São Paulo, Brazil, had been maintaining an undetectable viral load for 72 weeks after stopping his antiretroviral therapy (ART), however it was reported at the Conference on Retroviruses and Opportunistic Infections (CROI 2021) that his viral load had increased and that he had once again restarted ART.
The case of the ‘Sao Paulo Patient’ was first reported on at the International AIDS Society Conference (AIDS 2020), at which time he was the only person who had achieved long-term HIV remission without undergoing complex and risky procedures such as bone marrow transplantation – as was the case in the only other two known cures Timothy Brown (The Berlin Patient) and Adam Castillejo (The London Patient).
According to the researchers, the Sao Paulo Patient is a typical 35-year-old male living with HIV. He was diagnosed with HIV in 2012 and prescribed standard ART in line with local guidelines. In September 2015, among other participants, the Brazilian was included in a study where dolutegravir, maraviroc and nicotinamide were added to his regimen.
In March 2019, the patient stopped taking his ART. During this period, all clinical indicators were that the HIV was disappearing or becoming dormant. This was evidenced by frequent RNA and DNA testing for HIV. In addition, the level of antibodies to HIV in his blood steadily decreased – so much so that a rapid antibody test returned a non-reactive result. At the time of presentation in 2020 the patient’s viral load had remained undetectable (<50 copies/mL) for more than 15 months without ART.
It should be noted that of the five study participants who received a similarly boosted regimen that this patient was the only one who remained undetectable in the absence of active treatment.
Whilst the man was on the boosted regimen, he had an increase in the T-cell response to the HIV envelope proteins and Gag (the main structural protein of HIV), but these cell-mediated responses gradually disappeared in parallel with the decrease of HIV-specific antibodies after treatment interruption.
In September of 2020, the man was diagnosed with secondary syphilis, and in November after 72 weeks of treatment interruption, he developed painful symptoms – at this point his viral load was measured to be over 6300 copies/mL along with a notable rise in HIV antibodies. In December, the patient resumed treatment with a dolutegravir-based regimen and by January 1st 2021 his HIV viral load had once again returned to undetectable levels.
The scientists working on his case identified that the HIV strain he has now is different from the strain he was originally diagnosed with, this reason for this change is still unclear. Tests continue to understand whether the patient experienced a viral rebound due to the reappearance of ‘ancient strains’ as a result of a previous double infection; whether reinfection has occurred with a new strain or whether the patients HIV evolved in the absence of active treatment.
"Personally, I think this is not related to the evolution of the same strain," said Dr. Ricardo Diaz of the University of São Paulo, who presented the study.