With a global
estimate of 2.5 million new infections of HIV occurring yearly,
discovering novel methods to help stem the spread of the virus
is critical. The use of antiretroviral chemoprophylaxis for preventing
HIV after accidental or occupational exposure and in maternal
to fetal transmission has become a widely accepted method to combat
HIV. Based on this success, pre-exposure chemoprophylaxis (PrEP)
is being explored in at-risk patient populations such as injecting
drug users, female sex workers and men who have sex with men.
This off-label and unmonitored use has created a need for education
and intervention by pharmacists and other healthcare professionals.
Pharmacists should educate themselves on PrEP and be prepared
to counsel patients about their means of obtaining it (e.g. borrowing
or sharing medications and ordering from disreputable Internet
pharmacies). They should also be proactive about medication therapy
management in these patients due to clinically important drug
interactions with PrEP medications. Only one trial exploring the
safety and efficacy of tenofovir as PrEP has been completed thus
far. However, five ongoing trials are in various stages and two
additional studies are scheduled for the near future. Unfortunately,
studies in this arena have met with many challenges that have
threatened to derail progress. Ethical controversy surrounding
post-trial care of participants who seroconvert during studies,
as well as concerns over emerging viral resistance and logistical
site problems, have already halted several PrEP trials. Information
about these early trials has already filtered down to affected
individuals who are experimenting with this unproven therapy as
an “evening before pill”. The potential for PrEP is promising;
however, more extensive trials are necessary to establish its
safety and efficacy. Pharmacists are well-positioned to play a
key role in helping patients make choices about PrEP, managing
their therapy, and developing policy with an eye towards the future.
