Having Temporarily Suspended Disbelief, Would-Be Eradicatee Looks Forward
to Still Uncertain Future
A perilous seduction
Irrational exuberance might not be the sole domain of streets Broad and
Wall. Speculation in AIDS futures has also seen quite a run over the past
18 months. While both seem to be rooted in unseemly corporate
profitability, the latter wave of euphoria appears to have begun to cede to
a harsh and tenacious reality (if not yet to the full enormity of the
therapeutic and funding crises ahead.) And as the pendulum begins its
inexorable swing back to a more sober state of affairs (see Nightline, July
25, 1997 as well as the front page of The New York Times, August 22, 1997),
Gregg Gonsalves offers his view of "The State of AIDS," which he first
delivered at a D.C. forum sponsored by the AIDS Action Council this past
July.
I found out I was HIV+ positive a little over two years ago in March of
1995. At that time, I was helping take care of my cousin Carl, who died of
AIDS that year in July. It was a gruesome death from lymphoma that dragged
on for months and months. At that time, there was nothing that could have
saved Carl and nothing that looked like it could spare me from his fate.
How dramatically the popular outlook has changed in the past two years. As
one of ten volunteers in a clinical trial run by David Ho and Marty
Markowitz at the Aaron Diamond AIDS Research Center, I am now taking a
triple combination of AZT, 3TC and nelfinavir. Since beginning treatment,
my viral load has plummeted from some 200,000 copies per cubic milliliter
of blood to under 100, and there is no detectable HIV RNA in my
gut-associated lymphoid tissue (GALT), semen or cerebrospinal fluid (CSF).
My T-cells have risen from 270 per cubic milliliter to 470. And while I do
not think I will escape a death from this horrible disease, I do think I
have been given a substantial respite from disease progression -- at least for
now.
We've all heard virologic success stories like this in the press over the
past year. Today, however, I would like to focus on the caveats about these
triple and quadruple combination regimens -- and their failure to offer
significant hope for hundreds of thousands of people with HIV infection.
For the past 18 months, our expectations and our public policy have been
driven by a giddy optimism. It's now time though, I'm afraid, to remove the
rose-colored glasses and face the real challenges that lie ahead.
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The new intensive treatment strategies, now known as highly active
antiretroviral therapy (or HAART), are indeed remarkably successful in
suppressing viral replication in patients with little history of taking
anti-HIV medications. Thousands and thousands of HIV+ individuals, however,
(including many of my friends who have been infected for more than a couple
of years) have listened to the prevailing medical wisdom of years past and
taken AZT, ddI and ddC, combined these drugs or added 3TC or d4T. Many
later took saquinavir, the grossly impotent but deftly marketed protease
inhibitor when it was the first of its class of drugs commercially
available in the fall and winter of 1995. The result: thousands of HIV+
individuals are resistant to many of the component drugs in the triple
combinations that have shown so much promise in patients naïve to
antiretroviral therapy. If they have developed protease inhibitor
cross-resistance from earlier saquinavir use, the newer and more potent
protease inhibitors, ritonavir, indinavir and nelfinavir are of limited use
to them. If they haven't developed protease cross-resistance, but are
resistant to AZT and its cousins, they will likely get some benefit from
the use of protease inhibitors, but are essentially using a single agent to
control HIV. Monotherapy, even with the most potent protease inhibitor,
cannot hold the virus at bay for long.
What do we know about my own chances -- and of people like me -- for beating this
virus? I have no detectable virus in my body right now, but even this claim
is partly artifactual (for reasons I'll soon explain). No one now believes
that even the most successful of these combination regimens is capable of
completely shutting down viral replication. The embers may be gray and
smoldering, but they continue to burn. What my bloodwork and clinical
picture will look like in a year or two from now is anybody's guess. My
future depends on several factors. First, if I am to get the most out of
the drugs I am taking and want to forestall the development of drug
resistance, I will have to maintain a daunting daily medication regimen. I
take over two dozen pills a day. In addition, to my antiretroviral therapy,
I take a drug to control the debilitating diarrhea caused by the protease
inhibitor and a drug to control the esophagitis that sent me to the
emergency room this winter. If I miss even a single dose of my pills, I
greatly increase the risk of HIV's developing resistance to these agents.
Even if I can take my drugs regularly for the next few years, my future is
far from certain. Recently, 3 of the 10 people in my clinical trial found
out their virus had broken through, with once "undetectable" plasma HIV
levels becoming detectable again and beginning to climb upward. What
happened is uncertain, but its clear that being "undetectable" doesn't
mean there is no viral replication taking place. In fact, recent studies
show that most individuals who are "undetectable" by commercially available
assays have detectable levels of virus using the more sensitive assays
available in research laboratories. What's more, being "undetectable" by
even the most sensitive test still means there are thousands of infected
cells in the body. Even in the presence of highly active antiretroviral
therapy that's working, we now know that HIV can continue to evolve and
develop drug resistance.
Will I too break through on my therapy one day? The pertinent question, it
seems, is not if but when. I had a scare a few months ago when the amount of the virus in my blood blipped up to detectable levels and then
went back down again. After sequencing the virus from that unsettling
episode, my doctors told me there was no evidence I had developed genetic
resistance to the drugs I am taking. Because we now know that triple
combination therapy can fail without the development of specific
drug-resistance mutations, their consoling words left me cold. It is clear
that I am playing a game of beat-the-clock with a wily adversary. To throw
yet another roadblock in the way of the virus, I am thinking of adding a
fourth drug to my already onerous cocktail. If I still cant hold back
the virus and break through, I will have few (if any) therapeutic options
left. There is almost nothing in the new drug pipeline that isnt
cross-resistant to the drugs currently on pharmacy shelves.
Will we ever be able to claim victory over the virus using the drugs we
have now? All evidence to date suggests not. Even if I am successful in
keeping the virus from replicating inside me, the virus has integrated its
DNA into the DNA of many of my T-cells and macrophages and quietly sits
waiting for its day in the sun. It will take a long time on
therapy -- estimates range from 3 to 6 years -- for the cells harboring viral DNA
to be rooted out of my body. Meanwhile, there are places in my body where
the drugs cant reach -- particularly the brain -- that act as sanctuary sites
for my viral invader. And the clock is ticking. And ticking.
We havent beaten HIV, not by a long shot. We are in the eye of the storm,
and that second wall of wind is likely to strike us with all the brutal
impact of the first. Yes, weve seen our friends rise from their deathbeds.
Miraculously, the disabled returned to work. Weve bought ourselves some
time, but we mustnt fool ourselves into thinking the storm has passed.
Thats the perilous seduction of the eye. If we craft national policy on
AIDS based on this false sense of security -- an idea that the worst of this
epidemic is over -- were going to get one hell of a surprise and another hell
of a mess to clean up a few years hence.
The twentieth century has been one of incredible hubris when it comes to
pestilence. We thought we had beaten common bacterial infections and
diseases like tuberculosis through antibiotics, or like malaria through
antiparasitic drugs and the destruction of mosquitoes with pesticides. In
each of these cases, it is the bug that had the last laugh as it roared
back evading our most sophisticated attacks. We can acknowledge the
progress we have made in the treatment of HIV infection without succumbing
to a premature triumphalism that will eventually undo us. We can take
advantage of the virus momentary retreat to fortify ourselves and plan for
the next battle. Here are a few that we can do right now:
Expedite Drug Discovery. The cross-resistance profile of the drugs we
have now means that people with HIV infection who are antiretroviral naïve
have one or two rounds of triple combination therapy to use against HIV
before they are defenseless against the virus. Those who have long
histories of previous antiretroviral use may already have no therapeutic
options left. We need to develop drugs that are effective against
drug-resistant strains of HIV and that are directed against other targets
besides the viral reverse transcriptase and protease. Drugs like these are
years away. AIDS treatment advocates need to turn their energies toward
drug discovery efforts and toward speeding the development of novel
antiretroviral agents. We can begin by scrutinizing federally sponsored
programs such as the National Institute of Allergy and Infectious Diseases
National Cooperative Drug Discovery Groups and its Strategic Program for
Innovative Research on AIDS Therapies (SPIRAT); the National Cancer
Institutes Developmental Therapeutics Program and its Frederick Cancer
Research and Development Center; the National Institute for General Medical
Sciences structural biology program and the National Institute of Diabetes
and Digestive and Kidney Diseases small integrase discovery program.
Refine the Standard of Care. Many doctors are now recommending early
treatment with triple combination regimens and the new federal guidelines
for the use of antiretroviral therapy recommend their use in selected
settings in early disease. While we know that the new therapies for HIV
infection can extend survival and disease-free time in patients with
intermediate and advanced HIV infection, we do not know if early use of
these drugs will accomplish the same goals. It quite possible that the
long-term effects of these therapies will cannabilize the short-term
benefits of viral suppression. We need to know the relative merits of early
versus deferred highly active antiretroviral therapy by conducting a
clinical study to answer this question. Prescribing early intervention with
these powerful agents when they may not be warranted may deprive patients
of effective therapeutic options in the future. Adherence to these
complicated regimens may become difficult to maintain over the long term
leading to the development of multi-drug resistance in a large population
of HIV+ individuals.
Assess the Efficacy of New Diagnostic Tools. Genotypic and phenotypic
assays of viral resistance are now in development and are already being
used by a few physicians to guide the care of their patients. The
usefulness of these tests in clinical practice is yet to be determined and
needs to be assessed through clinical studies.
Assess the Epidemiology of Drug Resistance. Thousands of people with HIV are already resistant to the full armamentarium of antiretroviral
therapies. Many others who are now on triple combination regimens will
also develop drug resistant strains of the virus. With the widespread use
of these agents, transmission of multi-drug resistant strains of HIV is
likely to occur. The National Institutes of Health should set up a program
to track the prevalence of drug resistance and the incidence of
transmission of drug resistant strains of HIV.
Return to the Immune System. While we can suppress HIV replication to
very low levels, we cannot restore immune systems ravaged by years of
infection with the virus. We need to invest in basic and clinical
immunological research which can help us understand the extent of
immunological damage caused by HIV and ways to reverse the process. In
addition, we need to understand more about the biology of cells of the
immune system such as dendritic cells, macrophages, and brain macrophages
or microglia which may provide sanctuary for HIV under HAART.
Educate People with HIV and Their Primary Care Providers. While the
treatment of HIV infection has always been complicated, the new therapies
make the optimal treatment of the disease an even more sophisticated task.
New resources need to be made available to train medical providers in the
complexities of HIV polytherapy and to educate patients about the benefits
and risks of these new regimens. A portion of these resources can be
marshalled through the use of existing funds appropriated by Congress for
the Ryan White Care Act and the AIDS Education and Training Centers. While
a new funding line for treatment education is unlikely to be forthcoming
from such a penny-pinching Congress, AIDS advocates have to be creative in
identifying dollars for this important work. In addition, the
pharmaceutical industry should establish a fund run by an independent and
unbiased third party to support community based treatment education
programs.
The Honeymoon Continues
Data from the 23rd ACTG Meeting Document Reduction in Number of
Opportunistic Infections in the Era of HAART
Its a good thing
Since the approval and wide-spread use of protease inhibitors in mid-1996,
AIDS clinicians and primary care physicians across the country all insist
they are seeing a marked decrease in AIDS-related opportunistic infections
(OIs) in their HIV-positive patients. Until now, this was all wonderful yet
anecdotal news. At the 23rd AIDS Clinical Trials Group (ACTG) Meeting in
Washington, D.C. (July 19-23, 1997), a number of investigators presented
epidemiologic data which clearly demonstrate that the rate of most OIs has
indeed fallen.
The most striking presentation, which one would have missed unless one
happened to stumble into the Protozoa Pathogen Study Group symposium, came
from Tulane Universitys Rebecca Clark. Clark presented epidemiologic data
from the CDC sponsored Adult Spectrum of Disease Cohort (ASDC) from
December 1994 to July 1997. Baseline characteristics were used to group
1,181 patients before 1996 and 1,248 patients after 1996. A quick scan of
the baseline characteristics revealed three important statistically
significant differences between the groups: 1) The percentage of women in
the latter group increased from 15.6% to 19.5% (p=0.01); 2) The percentage
of gay/bisexual individuals in the latter group decreased from 49.7% to
43.1% (p<0.01); and 3) The latter group improved immunologically (53.5% of
the individuals before 1996 had CD4 counts <50 cells compared to 43.5%
after 1996 (p<0.01)). Although these data extend only through the first six
months of 1997, it is presumed that the the trend will continue throughout
the end of the year. When comparing the rate of the most common OIs,
including Pneumocystis carinii pneumonia (PCP), cytomegalovirus (CMV)
Mycobacterium avium complex (MAC), esophageal candidiasis, and wasting
from 1994, 1995 and 1996 with those from the first six months of 1997, the
decrease is staggering.
In comparing the 18 months before and after January 1996, however, the data
reveal that only 5 of the 11 OIs have decreased significantly: MAC, CMV,
KS, wasting, PCP. Decreases in the incidence of cryptococcal meningitis,
toxoplasmosis, cryptosporidiosis, and esophageal candidiasis, by contrast,
were not significant (although the reductions in meningitis and
toxoplasmosis approached significance). Furthermore, the marked and visible
decrease in opportunistic infections in Clarks study did not occur until
the calendar year 1997 -- even though 3 of the 4 protease inhibitors were
approved and available by mid-1996. Is it enough to say that these
decreases are solely due to the antiviral effect of triple combination
therapy? Might there not be other factors involved, such as increased use
MAC prophylaxis, steroid usage or dietary changes for the prevention of
wasting, or a change in sexual behavior in order to avoid KSHV and thus
Kaposis?
A preliminary data analysis of the OI events in ACTG 320 was presented by
USCs Judith Currier, an excellent young investigator whos taking the
ACTG by storm. ACTG 320 was Mercks indinavir clinical endpoint study which
randomized 1,156 patients with CD4 counts <200 and at a minimum of six
months prior AZT therapy to add either 3TC (n=579) or to add both 3TC and
indinavir (n=577). To no ones surprise, ACTG 320 was stopped early because
of statistically significant differences in deaths and AIDS events favoring
the protease inhibitor-containing group. There were 60 OIs in the group
that added one drug and 31 OIs in the group that added both 3TC and
indinavir. A detailed analysis of the clinical events in ACTG 320 is
currently underway (as well as a possible comparative analysis with ACTG
175). Nonetheless, it is probably safe to say that the incidence of OIs in
the triple therapy arm of ACTG 320 is the lowest ever documented in a study
of this size with this patient population. It will be interesting to see
whether or not some of these OIs (i.e., PCP and MAC) developed in
individuals on prophylaxis and also at what CD4 count. That is, Did
increases in CD4 cell counts protect these individuals from new
opportunistic infections?
CD4 cell increases and an "undetectable" viral load are one thing, but this
decrease in life-threatening OIs is the proof of the pudding and arguably
the reason we are finally seeing a substantial decline in AIDS deaths.
Numerous studies have documented the deleterious effect OIs have on
HIV-infected persons: the inflammatory cascade where one OI seems to lead
directly to another; the independent predictability of at least six OIs to
shorter survival; and the well-documented viral load surges which accompany
many OIs. So, in the ineradicable mantra of Martha Stewart, this reduction
in OIs is "a good thing."
Nevertheless, investigators at the ACTG meeting expressed caution that we
are in a "honeymoon phase." Clinical follow-up of ACTG 320 was, after all,
less than one year. And widespread use of protease inhibitors has just
recently crossed the one year mark. There are many who fear that in 6 to 18
months we might see a substantial number of patients fail their protease
inhibitor regimens (because of resistance and noncompliance) and experience
anew a marked increase in the incidence of opportunistic infections.
If this is indeed to be the case, only effective OI prophylactic regimens,
(TMP-SMX for PCP and clarithromycin or azithromycin for MAC) can insure
patients with viral break-through and faltering CD4 cell counts protection
from the opportunistic infection menace. Even then, prevention of CMV will
remain problematic. Roches outrageously expensive oral ganciclovir (the
closest thing we have to a prophylactic against CMV -- whatever happened to
lobucavir?) is only truly effective in CMV DNA-PCR-negative patients (that
is, those at the lowest risk of developing CMV disease). What are we to do
with those high-risk patients with high levels of CMV DNA in their blood?
Dont look for any help from Basel. Roche execs are said to be
reconsidering the potential market for its oral ganciclovir prodrug
(RS-79070) now that the incidence of CMV disease appears to have fallen so.
But such a short-sighted business decision would be, well, myopic. Even if
this business is all about the bottom line, slowing or discontinuing the
development of RS-79070 is (in as little as a year or two from now) very
likely to be exposed as strategic miscalculation. Woe to s/he who wields
that red pen.