An 18-year-old female has been able to maintain an undetectable viral load for more than 12 years after interrupting early antiretroviral therapy, according to a study presented at IAS 2015, in Vancouver, Canada.
Speaking on behalf of the study researchers, Asier Saez-Cirion, Ph.D., presented data detailing the teenager's continued HIV remission, which the researchers define as:
HIV remission should allow patients to durably discontinue therapeutic intervention, without (i) developing HIV-associated morbidities, (ii) showing decline of clinical parameters or progression to disease, (iii) while maintaining viremia at the lowest levels to avoid enhancing risk of transmission of infection.
For background, since 1996, the ANRS pediatric cohort known as CO10 EPF has followed 187 children born with HIV, 100 of whom have received combination antiretroviral therapy before 6 months of age. Of those, 15 have interrupted treatment while their viral loads were below 500 (the average time on treatment was 33 months).
The researchers estimated the probability was 13% for these 15 children to still control HIV two years after treatment interruption. Of the 15 children, 13 lost control of the virus within a year, while one was able to control the virus for over three years before viral rebound. The young woman, however, has continued to control the virus for over 12 years.
The teenager was infected during birth and was given zidovudine (AZT, Retrovir) as prophylactic treatment. She had an undetectable HIV-RNA viral load at day 3, and an undetectable HIV-DNA viral load at days 3 and 14. After six weeks, the zidovudine treatment was interrupted. At three months, her viral load increased sharply and she was started on combination antiretroviral therapy.
The girl was then lost to follow-up between 5.8 and 6.8 years of age, but when she returned to care she had an undetectable viral load despite interrupting treatment months earlier.
Since then, despite not being on treatment, the young woman's viral load has been below 50 (except for one blip of 515) for over 12 years. HIV DNA has consistently been detected in her circulating CD4+ cells at very low levels, however viremia is undetectable (although viral replication can be induced in vitro). Additionally, her CD4+ cell count has remained stable.
Interestingly, like the adults in the ANRS VISCONTI study (who have been able to control HIV without treatment after very early initiation of antiretroviral therapy), the teenager does not have a favorable HLA background for controlling HIV infection.
Nevertheless, this is the first case that shows that very long-term HIV remission is possible after very early treatment in perinatally infected children.
"Understanding the ability to durably contain HIV replication may guide new strategies towards HIV remission," the researchers concluded.