Research to improve current treatments includes decreasing side
effects of current drugs, further simplifying drug regimens to improve
adherence, and determining better sequences of regimens to manage drug
resistance. However, only a vaccine is thought to be able to halt the pandemic.
This is because a vaccine would cost less, thus being affordable for developing countries, and would not require daily treatment. However, after over 20 years of research, HIV-1
remains a difficult target for a vaccine, and there is as yet no cure.
Stem cell transplantation
In 2007, Timothy Ray Brown, a 40-year-old HIV-positive man, also known as "the Berlin
Patient", was given a stem cell transplant as part of his treatment for acute myeloid leukemia (AML). A second transplant was
made a year later after a relapse. The donor was chosen not only for genetic compatibility but also for being homozygous for a CCR5-Δ32 mutation that confers resistance to HIV
infection. After 20 months without
antiretroviral drug treatment, it was reported that HIV levels in Brown's
blood, bone marrow, and bowel were below the limit of detection. The
virus remained undetectable over three years after the first transplant. Although
the researchers and some commentators have characterized this result as a cure,
others suggest that the virus may remain hidden in tissues such as the brain (which acts as a viral reservoir). Stem cell treatment remains investigational because of itsanecdotal nature, the disease and
mortality risk associated with stem cell transplants, and the difficulty of
finding suitable donors.
Immunomodulatory agents
Complementing efforts to control viral replication, immunotherapies that may assist in the recovery of the immune
system have been explored in past and ongoing trials, including IL-2 and IL-7.
The failure of vaccine candidates to protect against HIV infection
and progression to AIDS has led to a renewed focus on the biological mechanisms
responsible for HIV latency. A limited period of therapy combining
anti-retrovirals with drugs targeting the latent reservoir may one day allow
for total eradication of HIV infection. Researchers have discovered an abzyme that can destroy the protein gp120CD4 binding site. This protein is common to all HIV variants as it
is the attachment point for B lymphocytes and subsequent
compromising of the immune system.
http://en.wikipedia.org
ไม่มีความคิดเห็น:
แสดงความคิดเห็น