At AIDS 2016, Scott
McCallister of Gilead presented results from an analysis of de-identified
patient-level prescription data from 80% of US retail pharmacies that dispensed
Truvada between January 2012 and
The researchers used
an algorithm to filter out Truvada
prescriptions that probably were not for PrEP, excluding people who used
it for HIV treatment (indicated by a recorded HIV diagnosis, opportunistic
illnesses or use of other antiretrovirals), HIV post-exposure prophylaxis (PEP)
or off-label treatment of hepatitis B.
The survey found that
a total of 79,684 unique individuals started Truvada for PrEP between early 2012 and the end of 2015. The
numbers rose from just 1671 prescriptions in the last quarter of 2012 to
14,000 in late 2015 – a 738% increase.
Of these PrEP users, 60,872 were men and 18,812
were women. Although women made up almost half (2740 out of 6210) of those who
started PrEP in 2012, the proportion fell to about a quarter (5051 out of
21,906) in 2015. While the absolute number of women taking PrEP rose slightly
over the four years, the much larger increase among men lowered women's share
of the total.
The overall mean age of people starting PrEP was
36 years, but the women were a bit younger than the men on average (33 vs 37
years, respectively). Further, while 28% of women taking PrEP were under age
25, this was only the case for 11% of the men.
A geographic breakdown showed that five states –
California, New York, Texas, Florida and Illinois – accounted for just over
half of all Truvada PrEP prescriptions nationwide. In addition to the large
size of these states, some are home to cities with large gay populations that
have promoted PrEP use within their communities and driven rapid increases, as
seen in San Francisco, New York City, Chicago and Seattle. But a smaller state
– Massachusetts – had the highest percentage of its residents on PrEP, at
Dr McCallister said that analysing data on the
race/ethnicity of PrEP users was more difficult because this information is
generally not included in pharmacy prescription records. He did say, however,
that those for whom this data were available were disproportionately white. At the recent ASM Microbe meeting Staci Bush of Gilead reported that among the 44% of PrEP users with
available data, white people made up 74%, with Hispanics (12%), African-Americans
(10%) and Asians (4%) accounting for much smaller proportions.
Dr McCallister noted that this breakdown of PrEP
users does not reflect the distribution of the HIV epidemic in the US.
According to the Centers for Disease Control and Prevention 44% of new HIV diagnoses occur among African-Americans, who make up about 12% of the US population. Young black gay and bisexual men are at especially high risk, and the
highest incidence rates are mostly seen in states in the southeast.
"Despite this US trend
of increasing use of [tenofovir/emtricitabine] for PrEP, barriers should be
address in those at high risk of HIV acquisition," including women, people
under age 25 and states with high infection rates, the researchers concluded.
agree that the number of people starting Truvada
for PrEP in Gilead's pharmacy survey is an underestimate of the total number of
PrEP users in the US. For example, the survey does not include people who receive PrEP
through the Medicaid system or private PrEP programmes such as Kaiser Permanente
in San Francisco.
McAllister's report said that looking at 2015 alone, a total of 2936 people
were prescribed PrEP in New York City; 1094 in San Francisco; 1001 in Chicago;
and 840 in Washington, DC. In contrast, a recent informal
of large PrEP providers in San Francisco put the cumulative number at more than 6000. While these figures are not strictly comparable, they
give a sense of the shortfall in the reported numbers.
Asked at an AIDS 2016 press conference about reasons
for the disparities in PrEP use in different populations, Dr McCallister
suggested that gay men and perhaps transgender people may have a greater
comfort level using PrEP because their providers are more knowledgeable and their
communities have done more peer-to-peer education. Women, on the other hand,
may have fewer "touchpoints" for accessing PrEP, as reproductive
health clinics and obstetricians/gynaecologists may not be as informed as sexual health clinics serving gay men,
highlighting the need for broader education and awareness efforts.
[Editor's note: In response to a follow-up query, Dr McCallister said that the large jump between the approximately 49,000 people reported at the ASM Microbe meeting and in the AIDS 2016 study abstract, and the 79,000 reported this week, is due to a switch to a more comprehensive pharmacy data source, which Gilead will use going forward.]