Can
Switching Antiretroviral Drugs Improve Vitamin D Levels?
By
Liz Highleyman
A
number of recent studies have shown that vitamin D deficiency
is common among people with
HIV, even more so than the population as a whole. Low
levels of vitamin D can contribute to bone loss, which in
turn can lead to fractures. Among HIV negative people, low
vitamin D levels have been linked to cardiovascular disease
and cancer.
Julie Fox from Guys and St. Thomas NHS Trust in London and
colleagues looked at vitamin D levels among participants in
the European MONET trial, which compared standard
ART -- consisting of a protease
inhibitor or NNRTI
plus a "backbone" of 2 nucleoside/nucleotide reverse
transcriptase inhibitors (NRTIs)
-- versus darunavir/ritonavir monotherapy.
As
previously reported, MONET enrolled 256 patients who were
taking a standard 3-drug ART regimen, had undetectable viral
load (< 50 copies/mL), and had no history of virological
treatment failure. They were randomly assigned to switch to
800/100 mg once-daily darunavir/ritonavir, either alone or
in combination with 2 NRTIs. Most participants (about 80%)
were men, about 90% were white, the median age was 44 years,
and the median CD4 cell count of 575 cells/mm3.
At
96 weeks, more than 90% of patients who switched from
a suppressive combination regimen to darunavir/ritonavir alone
maintained undetectable viral load, but monotherapy was not
quite as effective as 3-drug combination therapy, leading
to more frequent treatment failure.
Fox and colleagues analyzed data from 221 patients who had
their 25-hydroxyvitamin D levels measured before randomized
treatment started and again at week 96.
Results
 |
At
the screening visit, lower vitamin D levels were significantly
associated with the following factors: |
| |
 |
Calendar
month (P = 0.0067); |
|
Black
race/ethnicity (P = 0.013); |
|
Use
of efavirenz (P = 0.0062); |
|
Use
of zidovudine (P = 0.015). |
|
|
Mean
vitamin D levels were lowest from January through April
(35.8 nmol/L) and highest in September (45.4 nmol/L).
|
|
Patients
who discontinued efavirenz or zidovudine before starting
their MONET study regimen had significantly larger increases
in vitamin D between screening and week 96, compared with
those who stopped other drugs. |
Based
on these findings, the study authors recommended, "Routine
screening of HIV-positive patients for vitamin D should be
considered and the optimal management further defined."
"Given the evidence for health benefits of optimal vitamin
D levels, people with HIV infection should be monitored for
vitamin D levels," they elaborated in their discussion.
"For patients with severe vitamin D deficiency, the use
of vitamin D supplements or changes in antiretroviral treatment
could be considered."
"The
association between use of efavirenz and vitamin D deficiency
is consistent with previous cross-sectional and prospective
studies," they added. "To our knowledge, this is
the first report to show increases in vitamin D levels after
switching from efavirenz-based antiretroviral treatment to
[protease inhibitor]-based treatment."
Investigator
affiliations: Guys and St Thomas NHS Trust, London, UK; Janssen-Cilag
EMEA, Neuss, Germany; Hospital la Paz, Madrid, Spain; Pharmacology
Research Laboratories, University of Liverpool, Liverpool,
UK.
12/14/10
Reference
J Fox, B Peters, M Prakash, and others. Improvement in
Vitamin D Deficiency Following Antiretroviral Regime Change:
Results from the MONET Trial. AIDS Research and Human Retroviruses
(Abstract).
September 21, 2010 (Epub ahead of print).
