A number of studies showing a benefit to starting antiretroviral therapy earlier have been reported recently. These have resulted in important changes to guidelines including that infants should be treated immediately upon diagnosis and that adults should be treated as soon as their CD4 counts fall below 350 cells/mm3.
Determining the optimal time to start treatment is one of the most important unanswered questions about antiretroviral treatment. A large open-label treatment trial called START has begun and will likely answer this question within the next few years. It is open to HIV-positive volunteers with CD4 counts > 500 cells/mm3. Volunteers will be randomised to either start treatment immediately or defer treatment until their CD4 counts drop to below 350 cells/mm3 or treatment is clinically indicated.
A few of the studies showing the benefits of earlier treatment than guidelines previously recommended are listed below:
N Engl J Med. 2009 Apr 30;360(18):1897-9 [1].
Kitahata MM, Gange SJ, Abraham AG, Merriman B, Saag MS, Justice AC, Hogg RS, Deeks SG, Eron JJ, Brooks JT, Rourke SB, Gill MJ, Bosch RJ, Martin JN, Klein MB, Jacobson LP, Rodriguez B, Sterling TR, Kirk GD, Napravnik S, Rachlis AR, Calzavara LM, Horberg MA, Silverberg MJ, Gebo KA, Goedert JJ, Benson CA, Collier AC, Van Rompaey SE, Crane HM, McKaig RG, Lau B, Freeman AM, Moore RD; NA-ACCORD Investigators.
BACKGROUND: The optimal time for the initiation of antiretroviral therapy for asymptomatic patients with human immunodeficiency virus (HIV) infection is uncertain. METHODS: We conducted two parallel analyses involving a total of 17,517 asymptomatic patients with HIV infection in the United States and Canada who received medical care during the period from 1996 through 2005. None of the patients had undergone previous antiretroviral therapy. In each group, we stratified the patients according to the CD4+ count (351 to 500 cells per cubic millimeter or >500 cells per cubic millimeter) at the initiation of antiretroviral therapy. In each group, we compared the relative risk of death for patients who initiated therapy when the CD4+ count was above each of the two thresholds of interest (early-therapy group) with that of patients who deferred therapy until the CD4+ count fell below these thresholds (deferred-therapy group). RESULTS: In the first analysis, which involved 8362 patients, 2084 (25%) initiated therapy at a CD4+ count of 351 to 500 cells per cubic millimeter, and 6278 (75%) deferred therapy. After adjustment for calendar year, cohort of patients, and demographic and clinical characteristics, among patients in the deferred-therapy group there was an increase in the risk of death of 69%, as compared with that in the early-therapy group (relative risk in the deferred-therapy group, 1.69; 95% confidence interval [CI], 1.26 to 2.26; P<0.001). In the second analysis involving 9155 patients, 2220 (24%) initiated therapy at a CD4+ count of more than 500 cells per cubic millimeter and 6935 (76%) deferred therapy. Among patients in the deferred-therapy group, there was an increase in the risk of death of 94% (relative risk, 1.94; 95% CI, 1.37 to 2.79; P<0.001). CONCLUSIONS: The early initiation of antiretroviral therapy before the CD4+ count fell below two prespecified thresholds significantly improved survival, as compared with deferred therapy. 2009 Massachusetts Medical Society
PMID: 19339714
Lancet. 2009 Apr 18;373(9672):1314-6 [2]. Free full-text article [3].
When To Start Consortium, Sterne JA, May M, Costagliola D, de Wolf F, Phillips AN, Harris R, Funk MJ, Geskus RB, Gill J, Dabis F, Miró JM, Justice AC, Ledergerber B, Fätkenheuer G, Hogg RS, Monforte AD, Saag M, Smith C, Staszewski S, Egger M, Cole SR.
BACKGROUND: The CD4 cell count at which combination antiretroviral therapy should be started is a central, unresolved issue in the care of HIV-1-infected patients. In the absence of randomised trials, we examined this question in prospective cohort studies. METHODS: We analysed data from 18 cohort studies of patients with HIV. Antiretroviral-naive patients from 15 of these studies were eligible for inclusion if they had started combination antiretroviral therapy (while AIDS-free, with a CD4 cell count less than 550 cells per microL, and with no history of injecting drug use) on or after Jan 1, 1998. We used data from patients followed up in seven of the cohorts in the era before the introduction of combination therapy (1989-95) to estimate distributions of lead times (from the first CD4 cell count measurement in an upper range to the upper threshold of a lower range) and unseen AIDS and death events (occurring before the upper threshold of a lower CD4 cell count range is reached) in the absence of treatment. These estimations were used to impute completed datasets in which lead times and unseen AIDS and death events were added to data for treated patients in deferred therapy groups. We compared the effect of deferred initiation of combination therapy with immediate initiation on rates of AIDS and death, and on death alone, in adjacent CD4 cell count ranges of width 100 cells per microL. FINDINGS: Data were obtained for 21 247 patients who were followed up during the era before the introduction of combination therapy and 24 444 patients who were followed up from the start of treatment. Deferring combination therapy until a CD4 cell count of 251-350 cells per microL was associated with higher rates of AIDS and death than starting therapy in the range 351-450 cells per microL (hazard ratio [HR] 1.28, 95% CI 1.04-1.57). The adverse effect of deferring treatment increased with decreasing CD4 cell count threshold. Deferred initiation of combination therapy was also associated with higher mortality rates, although effects on mortality were less marked than effects on AIDS and death (HR 1.13, 0.80-1.60, for deferred initiation of treatment at CD4 cell count 251-350 cells per microL compared with initiation at 351-450 cells per microL). INTERPRETATION: Our results suggest that 350 cells per microL should be the minimum threshold for initiation of antiretroviral therapy, and should help to guide physicians and patients in deciding when to start treatment.
PMID: 19361855
N Engl J Med. 2008 Nov 20;359(21):2233-44 [4].
Violari A, Cotton MF, Gibb DM, Babiker AG, Steyn J, Madhi SA, Jean-Philippe P, McIntyre JA; CHER Study Team.
BACKGROUND: In countries with a high seroprevalence of human immunodeficiency virus type 1 (HIV-1), HIV infection contributes significantly to infant mortality. We investigated antiretroviral-treatment strategies in the Children with HIV Early Antiretroviral Therapy (CHER) trial. METHODS: HIV-infected infants 6 to 12 weeks of age with a CD4 lymphocyte percentage (the CD4 percentage) of 25% or more were randomly assigned to receive antiretroviral therapy (lopinavir-ritonavir, zidovudine, and lamivudine) when the CD4 percentage decreased to less than 20% (or 25% if the child was younger than 1 year) or clinical criteria were met (the deferred antiretroviral-therapy group) or to immediate initiation of limited antiretroviral therapy until 1 year of age or 2 years of age (the early antiretroviral-therapy groups). We report the early outcomes for infants who received deferred antiretroviral therapy as compared with early antiretroviral therapy. RESULTS: At a median age of 7.4 weeks (interquartile range, 6.6 to 8.9) and a CD4 percentage of 35.2% (interquartile range, 29.1 to 41.2), 125 infants were randomly assigned to receive deferred therapy, and 252 infants were randomly assigned to receive early therapy. After a median follow-up of 40 weeks (interquartile range, 24 to 58), antiretroviral therapy was initiated in 66% of infants in the deferred-therapy group. Twenty infants in the deferred-therapy group (16%) died versus 10 infants in the early-therapy groups (4%) (hazard ratio for death, 0.24; 95% confidence interval [CI], 0.11 to 0.51; P<0.001). In 32 infants in the deferred-therapy group (26%) versus 16 infants in the early-therapy groups (6%), disease progressed to Centers for Disease Control and Prevention stage C or severe stage B (hazard ratio for disease progression, 0.25; 95% CI, 0.15 to 0.41; P<0.001). Stavudine was substituted for zidovudine in four infants in the early-therapy groups because of neutropenia in three infants and anemia in one infant; no drugs were permanently discontinued. After a review by the data and safety monitoring board, the deferred-therapy group was modified, and infants in this group were all reassessed for initiation of antiretroviral therapy. CONCLUSIONS: Early HIV diagnosis and early antiretroviral therapy reduced early infant mortality by 76% and HIV progression by 75%. (ClinicalTrials.gov number, NCT00102960.) 2008 Massachusetts Medical Society
PMID: 19020325
Monday, June 8, 2009. National Institute of Allergy and Infectious Diseases (NIAID) - Press Release [5]
A clinical trial has demonstrated that HIV-infected adults in a resource-limited setting are more likely to survive if they start antiretroviral therapy (ART) before their immune systems are severely compromised.
On May 28, 2009, an independent data and safety monitoring board (DSMB) met to conduct an interim review of an ongoing clinical study known as CIPRA HT 001, which is being conducted in Haiti. The DSMB found overwhelming evidence that starting ART at CD4+ T cell counts—a measure of immune health—between 200 and 350 cells per cubic millimeter (mm3) improves survival compared with deferring treatment until CD4+ T cells drop below 200 cells/mm3. In light of these results, the DSMB recommended that the trial sponsor—the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health—end the trial immediately, before its scheduled conclusion. NIAID agreed with the DSMB recommendation, and all study participants who have fewer than 350 CD4+ T cells/mm3 will be offered ART.
The study investigators say this new finding has the potential to change the standard of care for HIV infection in dozens of countries around the world where ART is initiated only when CD4+ T cell counts drop below 200 cells/mm3. Like the results of several recent epidemiologic studies in developed countries that examined the optimal time to begin ART, the new finding underscores the importance of identifying people who are HIV-infected earlier in the course of their infection and starting ART earlier.
“The public health community now has evidence from a randomized, controlled clinical trial—the gold standard—that starting ART at CD4+ T cell counts between 200 and 350 cells/mm3 in resource-limited settings yields better health outcomes than deferring treatment until CD4+ T cell counts drop below 200 cells/mm3,” says NIAID Director Anthony S. Fauci, M.D.
“The number of people who meet the medical criteria for receiving ART likely will grow as treatment guidelines are revised as a consequence of this finding, challenging the global community to supply antiretroviral drugs to all who need them,” adds Carl Dieffenbach, Ph.D., director of the NIAID Division of AIDS. “Today, only 30 percent of HIV-infected individuals in low- and middle-income countries who need ART are receiving it.”
The clinical trial CIPRA HT 001 began in 2005. It is funded by NIAID through the Comprehensive International Program of Research on AIDS (CIPRA) and is being carried out by the Haitian Group for the Study of Kaposi’s Sarcoma and Immune Deficiency Disorders (GHESKIO) Centers in Port-au-Prince, Haiti. The principal investigator is Jean William Pape, M.D., the director of the GHESKIO Centers and a professor of medicine at Weill Medical College of Cornell University.
The trial enrolled 816 HIV-infected adults ages 18 and older with early HIV disease and CD4+ T cell counts between 200 and 350 cells/mm3. Half of the participants were assigned at random to begin ART within two weeks of enrollment, and the other half were assigned to defer treatment until their CD4+ T cell counts dropped below 200 cells/mm3 or they were diagnosed with AIDS. This deferred treatment is in keeping with the standard of care in Haiti and the current guidelines of the World Health Organization (WHO). The first-line treatment regimen consisted of the anti-HIV drugs zidovudine, lamivudine and efavirenz.
At the time of the DSMB interim review, six participants in the early treatment group had died, while 23 participants in the standard-of-care group had died—nearly four times as many. The DSMB also found that, among participants who began the study without tuberculosis (TB) infection, 18 people in the early treatment had developed TB, while 36 people—twice as many—in the standard-of-care group had developed TB. These results were statistically significant.
In light of these results, the DSMB recommended that NIAID end the trial immediately and that the study team offer ART to all participants in the standard-of-care group who have fewer than 350 CD4+ T cells/mm3. The DSMB also recommended that the study team continue to follow all participants for another year and make every effort to ensure that participants receiving ART continue their therapy. NIAID concurred with these recommendations.
The study investigators are notifying all participants and have notified institutional review boards and national ethics committees involved with CIPRA HT 001 as well as the Haitian Ministry of Health about the findings of the DSMB. Investigators also have shared the information with WHO, the U.S. President’s Emergency Plan for AIDS Relief, and the Global Fund to Fight AIDS, Tuberculosis and Malaria.
For more information about CIPRA HT 001, see Questions and Answers: The CIPRA HT 001 Clinical Trial [6].
For more information about HIV/AIDS prevention, treatment and research, go to www.aids.gov [7].
Links:
[1] http://www.ncbi.nlm.nih.gov/pubmed/19339714
[2] http://www.ncbi.nlm.nih.gov/pubmed/19361855
[3] http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=19361855
[4] http://www.ncbi.nlm.nih.gov/pubmed/19020325
[5] http://www3.niaid.nih.gov/news/newsreleases/2009/CIPRA_HT_01.htm
[6] http://www3.niaid.nih.gov/news/QA/CIPRA_HT01_qa.htm
[7] http://www.aids.gov