The Doctor's Channel - HIV/AIDS

Tenofovir-related renal dysfunction can't always be reversed

2010-03-09T16:55:19+00:00

NEW YORK (Reuters Health) - Tenofovir nephrotoxicity can't always be fully reversed in HIV-infected men, according to a new study.

Up to 2% of patients have adverse renal effects from the nucleotide reverse transcriptase inhibitor, and reportedly, kidney function rapidly normalizes when tenofovir is stopped. But "because of the few cases, limited follow-up and the insensitive measure used" (serum creatinine) in the previous reports, it's not known how reversible the nephrotoxicity really is, note senior author Dr. Andrew Carr, from St. Vincent's Hospital, Sydney, Australia, and colleagues.

In a paper published online February 19th in the Journal of Acquired Immune Deficiency Syndromes, Dr. Carr and his associates describe 24 men who discontinued tenofovir because their estimated glomerular filtration rate (eGFR) was less than 60 ml/minute/1.73 m2.

During a median of 30 months between start of tenofovir and drug cessation, median eGFR fell from 74 to 51 ml/min/1.73 m2 - a reduction about 10 times greater than expected with normal aging.

During the median period of 13 months after tenofovir discontinuation, eGFR rose by a median of 19 ml/min/1.73 m2. Most improvement occurred in the first month.

In only 10 (42%) patients did eGFR return to pre-tenofovir levels, and only two exceeded 90 ml/min/1.73 m2.

Twelve patients had eGFR increases above the median; this group had a more rapid monthly decline while on tenofovir compared to those with less improvement (1.9 vs 0.7 ml/min/1.73 m2, p = 0.009) and a shorter duration of tenofovir therapy (21 vs 51 months, p = 0.08), suggesting that "more acute renal damage is less likely to be permanent."

These patients were also more likely to have received protease inhibitors (100% vs 54%, p = 0.02). The authors explain that protease inhibitors can increase tenofovir levels in plasma and renal tubular epithelium. Therefore, the greater improvement was likely due to cessation of higher tenofovir exposure.

The single-center study was retrospective, relatively small and had a variable duration of follow-up, and so prospective validation in a larger, more heterogeneous population is needed, the researchers say.

Nevertheless, they conclude, earlier discontinuation of tenofovir might have led to greater improvements in renal function, "which underlines the importance of regular assessment and perhaps of earlier intervention."

Specifically, they advise, even gradual deterioration in eGFR to levels above 60 ml/min/1.73 m2 might be cause enough to discontinue tenofovir.

Reference:
J Acquir Immune Defic Syndr 2010.

Views: 4785
Rating:

Treatments for HIV/TB co-infection should start at the same time: study

2010-02-25T19:36:57+00:00

NEW YORK (Reuters Health) - In patients with HIV and tuberculosis (TB) whose CD4 cell counts are below 500/mm3, mortality is increased if antiretroviral therapy is delayed until TB treatment is finished, according to research from South Africa.

TB is the most common opportunistic infection and the most frequent cause of death in HIV-infected patients in developing countries, the authors say. In South Africa, nearly three-quarters of TB patients are co-infected with HIV.

But clinicians often hesitate to treat both diseases at the same time, because of potential drug interactions or overlapping side effects, the immune reconstitution inflammatory syndrome, high pill burden, and “programmatic challenges.”

In the February 25th issue of the New England Journal of Medicine, Dr. Salim S. Abdool Karim, at the University of KwaZulu-Natal, Durban, and colleagues report on their randomized open-label trial comparing simultaneous treatment with delayed antiretroviral treatment. Between 2005 and 2008, the study enrolled 642 co-infected adults with CD4 counts < 500/mm3.

In two integrated-therapy groups, a combined total of 429 patients received antiretroviral therapy starting either within 4 weeks after the initiation of TB therapy or within 4 weeks after the intensive phase of TB therapy (which lasted 2 or 3 months). In a sequential therapy group, 213 patients received HIV treatment only after completion of the 6- to 8-month anti-TB regimen.

TB treatment included rifampin, isoniazid, ethambutol, and pyrazinamide with or without streptomycin. HIV therapy included didanosine, lamivudine, and efavirenz, plus trimethoprim-sulfamethoxazole to protect against opportunistic infections.

On average, patients in the sequential therapy group started antiretroviral therapy 190 days later than those in the integrated-therapy group.

The authors report data up to September 1, 2008, when the data and safety monitoring committee advised that all patients in the sequential-therapy group be started on antiretroviral therapy as soon as possible.

At that point – 2 months after completion of enrollment in the study -- mortality rates per 100 person-years were 5.4 in the integrated therapy group and 12.1 in the sequential-therapy group (adjusted HR 0.43, p = 0.004).

Furthermore, the authors report, “mortality was lower in the integrated-therapy group in all CD4+ count strata.”

Rates of immune reconstitution inflammatory syndrome were 12.4% with integrated therapy and 3.8% with sequential therapy, although there were no related deaths or changes in antiretroviral regimen.

“The paradoxical deterioration in the clinical status is sufficiently common to warrant close clinical monitoring in the first few months after the initiation of antiretroviral therapy in patients co-infected with tuberculosis,” the authors advise.

Rates of other adverse events did not differ between groups.

The investigators acknowledge that they did not determine rates of death due to TB or HIV and that their study included only patients with sputum smears positive for acid-fast bacilli. They can’t make a definitive recommendation as to when antiretroviral therapy should be started during TB therapy until the trial is completed.

Dr. Karim’s group points out that World Health Organization (WHO) guidelines recommend delaying antiretroviral therapy until completion of TB treatment in patients with WHO stage 3 HIV infection and CD4+ counts exceeding 200 cells/mm3.

“Our findings,” they conclude, “suggest that this guideline should be expanded to include cotreatment of HIV infection and tuberculosis in patients with CD4+ counts of less than 500 cells per cubic millimeter.”

In a separate article in the same issue of the journal, researchers suggest that asking patients about three symptoms – cough or fever of any duration or night sweats lasting 3 weeks or more during the previous 4 weeks – can allow clinicians to accurately rule out TB in most HIV-infected patients.

Lead author Dr. Kevin P. Cain, from the U.S. Centers for Disease Control and Prevention, Atlanta, Georgia, and his associates point out that while WHO guidelines call for TB screening when HIV infection is first diagnosed, but there are no evidence-based guidelines for such screening.

Their prospective study – conducted in Southeast Asia -- was designed to develop a clinical algorithm for screening and diagnosis of TB in people with HIV infection in resource-limited settings.

Based on cultured samples of sputum, urine, stool, blood, and lymph-node aspirate (drawn from patients with lymphadenopathy), TB was diagnosed in 267 of 1748 patients (15%; age range 7 to 72 years, median CD4 cell count 242/mm3).

For a cough lasting more than 2 weeks, the sensitivity for TB was only 33%.

Asking patients about cough, fever and drenching night sweats had the highest sensitivity at 93%, with a specificity of 36% and a negative predictive value of 97%.

“This finding may…allow for safe initiation of isoniazid preventive therapy and antiretroviral therapy, if indicated, in people who reported having none of the three predictive symptoms,” the authors suggest.

Sputum smears were positive for fewer than half of patients with TB. The best performing diagnostic approach involved mycobacterial culture, but this modality is impractical in low-resource settings. ]

As a practical middle ground, Dr. Cain’s team points out, “Tuberculosis is relatively uncommon in patients with positive results of symptom screening if they have two negative smears, a normal chest radiograph and a CD4+ cell count of 350 or more per cubic millimeter.”

Reference:
N Engl J Med 2010;362:697-706,707-716.

Views: 872
Rating:

Several antiretroviral drugs linked to myocardial infarction

2010-01-27T23:06:02+00:00

NEW YORK (Reuters Health) – The nucleoside reverse transcriptase inhibitors (NRTIs) abacavir and didanosine, and the protease inhibitors (PIs) indinavir and lopinavir-ritonavir, all increase the risk of myocardial infarction (MI).

Still, the absolute risk of MI with any particular agent appears to be small, never exceeding 8 cases per 1000 person-years of follow-up, the report indicates.

“We have previously demonstrated an increased risk of MI among patients exposed to combination antiretroviral therapy for longer periods, particularly those exposed to PIs and those recently exposed to NRTIs abacavir and didanosine,” Dr. Signe Westring Worm, from the University of Copenhagen, and co-authors note.

With an additional year of follow-up in the Data Collection on Adverse Events of Anti-HIV Drugs study, the authors were able to assess the risk of MI with 13 anti-HIV agents, including tenofovir, a more recently approved NRTI. Included in the analysis were 33,308 HIV-infected patients.

Each of the agents met prespecified requirements for inclusion in the analysis (at least 30,000 person-years of follow-up with a median individual postexposure follow-up of >1 year). These drugs included: seven NRTIs (zidovudine, stavudine, didanosine, zalcitabine, lamivudine, abacavir, and tenofovir), 4 PIs (indinavir, nelfinavir, lopinavir-ritonavir, and saquinavir), and 2 non-NRTIs (efavirenz and nevirapine).

During 178,835 person-years of follow-up, 580 patients had an MI, according to the report in the Journal of Infectious Diseases for February 1.

Recent exposure to abacavir or didanosine increased the odds of myocardial infarction by 73% and 30%, respectively, after adjusting for latest lipid levels.

Similarly, cumulative exposure to abacavir, indinavir, and lopinavir-ritonavir increased the risk of myocardial infarction by 7%, 8%, and 9% per year, respectively.

By contrast, use of tenofovir, zalcitabine, zidovudine, stavudine, or lamivudine had no significant effect on the risk of myocardial infarction, the authors report.

This study “is one of the largest observational cohorts, representing thousands of individuals living with HIV infection,” Dr. Judith A. Aberg, from New York University School of Medicine, and Dr. Heather Ribaudo, from Harvard School of Public Health, Boston, comment in a related editorial.

The current findings, like the initial report of an association of abacavir with MI, spark controversy, the editorialists note. However, the results will also stimulate “further scientific study to understand the pathogenesis of cardiac risk and interventions to decrease such risk.”

J Infect Dis 2010.

Views: 1111
Rating:

Interruptions in anti-HIV therapy carry high risk of thrombocytopenia

2010-01-11T15:21:51+00:00

NEW YORK (Reuters Health) - In HIV-infected patients, risk factors for thrombocytopenia include interruptions in antiretroviral therapy, high HIV RNA levels, hepatitis C virus (HCV) infection, and cirrhosis, according to two papers in the Journal of Acquired Immune Deficiency Syndromes for December 15.

In the first paper, Dr. Marie-Anne Bouldouyre, from Hopital Saint Louis, Paris, and colleagues report that one in four patients who interrupted their highly active antiretroviral therapy (HAART) developed thrombocytopenia (<150,000 platelets/microliter) over the 96-week study period.

In the second study, Dr. Kristen M. Marks and colleagues at Weill Cornell Medical College, New York, and associates showed that the odds of thrombocytopenia (here defined as <100,000 platelets/microliter for >3 months) were increased by 5.3-fold with an HIV RNA level >400 copies/mL, by 6.1-fold with HCV infection, and by 24.0-fold with cirrhosis.

A number of studies have examined antiretroviral treatment interruptions as a way of making therapy more manageable, Dr. Bouldouyre and colleagues note. Even though the results indicate that such an approach yields "unacceptable" increases in morbidity and mortality, some patients still stop their medications for periods of time.

To examine the impact of interrupted antiretroviral therapy on platelet counts, the authors analyzed data from 391 "well-suppressed" patients who had been randomized to receive HAART either intermittently (8 weeks off, 8 weeks on) or continuously for 96 weeks as part of an earlier trial.

At 96 weeks, the thrombocytopenia rate was much higher in the intermittent therapy group than in the continuous treatment group: 25.4% vs. 9.8% (p < 0.001). Moreover, the median time to thrombocytopenia in the former group was just 9 weeks compared with 40 weeks in the latter.

On multivariate analysis, intermittent therapy upped the odds of thrombocytopenia by 4.1-fold (p < 0.0001). Other risk factors included a history of thrombocytopenia (OR, 11.9) and a low baseline platelet count (OR, 3.4). Moreover, the authors found that as platelet counts fell, so did CD4+ cell counts, while HIV RNA levels rose.

In the paper from the New York-based group, the authors note that thrombocytopenia was a common finding in HIV patients during the 1980s and early 1990s, but little has been reported since the introduction of potent antiretroviral therapy in the mid 1990s.

Their case-control study included 146 HIV-infected patients with and without thrombocytopenia who were seen at two HIV clinics at New York Presbyterian Hospital-Weill Cornell Center in the last few years. Cases and controls were matched by age, gender, and first clinic visit.

Fifty-eight percent of case patients had platelet counts of 50,000/microliter or lower and 38% had levels of 30,000/microliter or lower. As noted, uncontrolled HIV replication, HCV infection, and cirrhosis were all risk factors for thrombocytopenia.

Major bleeding events (gastrointestinal, intracranial, or requiring hospitalization) were 6.5-times more common in case patients than in controls (p = 0.014).

Reference:
J Acquir Immune Defic Syndr 2009;52:531-537,595-599.

Views: 2903
Rating:

Antiretroviral therapy start-up linked to genital ulcers in women

2010-01-07T13:24:06+00:00

NEW YORK (Reuters Health) - Genital ulcers are common in HIV-infected women when antiretroviral therapy (ART) begins, particularly when CD4 counts are low or when women have had these ulcers in the past, according to prospective data from Kenya.

“The most surprising finding was that this increased risk was limited to the first month,” lead author Dr. Susan M. Graham from the University of Washington, Seattle told Reuters Health. “An earlier study…had indicated that the risk of immune reconstitution-related genital ulcer disease was increased during the first 6 months of therapy.”

The current study followed HIV-infected women prospectively, so the results provide a more accurate estimate of the risk after ART, she added.

In the December 15th Journal of Acquired Immune Deficiency Syndromes, Dr. Graham and her colleagues note that genital ulcer disease is of particular concern during HIV infection, since mucosal breakdown and local inflammation increase viral shedding at the ulcer site, thereby increasing the risk of transmission.

The researchers performed exams at baseline and then monthly on 134 Kenyan women who were starting ART with either stavudine or zidovudine combined with lamivudine and nevirapine. The median baseline CD4 cell count was 127, and 82 women had a documented history of GUD.

During the first 6 months of ART (85 visits), 54 women (40.3%) had genital ulcers. The prevalence of the ulcers rose from 9.7% at baseline to 16.7% one month after ART was initiated (adjusted odds ratio 1.9, p = 0.04), and then fell to 6.4% by month 6.

“Immune reconstitution inflammatory syndrome (IRIS) is a term used to describe the paradoxical worsening of preexisting infectious processes following ART initiation,” Dr. Graham explained. “Chronic infections such as genital herpes simplex virus type 2 (HSV-2) may flare when the host regains the capacity to mount an inflammatory response, but is still unable to control the infection completely.”

Ulcers were more frequent in women with a history of genital ulcer disease (13.9% vs 3.9%, p < 0.001). In multivariate analysis, a baseline CD4 cell count below 100 and a history of genital ulcers were independent predictors of risk after initiation of antiretroviral therapy.

Dr. Graham recommends that for women with known HSV-2 infection, suppression with acyclovir may help prevent genital ulcer recurrence, promote ulcer healing, and decrease HIV-1 shedding.

When serologic tests for herpesvirus are not available, “suppressive therapy with acyclovir at ART initiation and for up to 6 months thereafter could be considered” for women with a history of recurrent genital ulcers, she added.

The researchers emphasize that women with a history of genital ulcers should be counseled about the potential for increased transmission risk during the first few months of ART.

Reference:
J Acquir Immune Defic Syndr 2009;52:600-603.

Views: 2380
Rating:

Tenofovir-emtricitabine favored as fixed-dose combo for HIV infection

2009-11-16T13:41:07+00:00

NEW YORK (Reuters Health) – New research indicates that tenofovir 300 mg-emtricitabine 200 mg (TDF-FTC) is comparable to abacavir 600 mg-lamivudine 300 mg (ABC-3TC) in anti-HIV efficacy but is associated with fewer serious adverse events.

According to the report in the November 15th issue of Clinical Infectious Diseases, serious non-AIDS events, especially cardiovascular ones, were less common with TDF-FTC during the two-year study. Moreover, TDF-FTC-treated patients were less likely to require lipid-lowering therapy.

Conversely, TDF-FTC was associated with greater bone mineral density loss, but this did not translate into a higher fracture rate, the report indicates.

In the 96-week STEAL study (Simplification with Tenofovir-Emtricitabine or Abacavir-Lamivudine), 357 patients were randomized to replace their current nucleoside treatments with either TDF-FTC or ABC-3TC. The study subjects’ mean age was 45 years, and 98% were men. Thirty percent had been receiving TDF, 20% ABC, and 24% a protease inhibitor. None were positive for human leukocyte antigen-B*5701 and none had HIV levels above 50 copies/mL.

The virologic failure rate, defined as consecutive viral loads of >400 copies/mL, was low and similar in each group: 3.9% for TDF-FTC and 5.6% for ABC-3TC, Dr. Andrew Carr, from St. Vincent’s Hospital, Sydney, Australia, and co-researchers note.

None of the patients developed AIDS, although 18 did experience a serious non-AIDS event, including 4 that were fatal. As noted, patients treated with TDF-FTC had a lower rate of such events than did those given ABC-3TC: 1.2 vs. 4.8 events per 100 patient-years (p = 0.012). This was driven mostly by a lower rate of cardiovascular events in the TDF-FTC group: 0.3 vs. 2.2 events per 100 patient-years.

In a related editorial, Dr. Peter Reiss, from the Academic Medical Center, Amsterdam, the Netherlands, comments, “Given the widespread use of ABC-3TC and TDF-FTC fixed-dose combinations as part of currently preferred combination antiretroviral therapy regimens, the results of the STEAL trial…are both timely and informative.”

Reference:
Clin Infect Dis 2009;49:1591-1601,1602-1604.

Views: 2594
Rating:

Antiretroviral therapy may reverse HIV-induced lung abnormalities

2009-09-21T13:25:16+01:00

NEW YORK (Reuters Health) - Antiretroviral therapy does not adversely affect lung function in HIV-infected patients and may actually have a beneficial effect, according to study findings presented Monday at the Interscience Conference on Antimicrobial Agents and Chemotherapy in San Francisco.

"No recent longitudinal studies on lung function in HIV patients have, to our knowledge, been published," lead researcher Dr. Ulrik Kristoffersen, from Rigshospitalet, Copenhagen, told Reuters Health.

"Over 4.5 years of follow-up of 63 HIV patients, pulmonary function seemed to improve," he noted. "The vast majority of the patients received antiretroviral treatment throughout the study. The improvements were especially observed in the non-smoking patients."

At the start of the study in 2001, lung function testing was performed on all the subjects, of whom about half were smokers.

Two principle lung abnormalities were seen at baseline: impaired gas exchange from the alveoli to the blood and an increase in the residual volume of the lung. The former, the researchers note, suggests pulmonary inflammation, while the latter indicates lung tissue destruction.

When the lung function tests were repeated at the end of the study, gas exchange had normalized in non-smokers. Lesser improvements were seen in smokers.

As for residual lung volume, non-smokers showed normalization of this parameter as well. In smokers, however, the residual volume was further increased, indicating ongoing lung damage.

"Antiretroviral therapy seems not to negatively affect lung function in HIV patients but seems instead to be able to reverse abnormal lung parameters initially observed," Dr. Kristoffersen said. "Hence, there is no necessity for routine monitoring of lung function in HIV patients."

Moving forward, he said that future longitudinal studies looking at antiretroviral therapy in treatment-naïve patients should include lung function testing.

Views: 4069
Rating:

Resistance testing advised for all HIV-infected patients: guidelines

2009-08-14T15:58:32+01:00

NEW YORK (Reuters Health) – Newly updated guidelines for managing persons infected with HIV recommend that all patients undergo genotypic resistance testing even if there are no immediate plans to initiate antiretroviral therapy.

“Because drug-resistant virus can be transmitted from one person to another, all patients should be assessed for transmitted drug resistance with an HIV genotype test upon initiation of care,” the guidelines state. “If therapy is deferred, repeat testing at the time of antiretroviral therapy initiation should be considered because of the potential for superinfection.”

The new guidelines, an update of recommendations issued in 2004, were prepared by an expert panel of the HIV Medicine Association of the Infectious Diseases Society of America. The guidelines are based on research published from 2003 to 2008.

Lead guideline author Dr. Judith A. Aberg, from Bellevue Hospital Center, New York, and colleagues report their recommendations in the September 1st issue of Clinical Infectious Diseases.

“The guidelines,” the authors note, “are intended for use by healthcare providers who care for HIV-infected patients or patients who may be at risk for acquiring HIV infection.”

Some of the other new recommendations in the guidelines include:
--Varicella zoster virus-negative patients or those without a chickenpox or shingles history should be given VZV immune globulin as soon as possible after exposure to a person with chickenpox of shingles.
--To reduce the risk of an allergic reaction, HLA-B*5701 testing should be done in candidates for abacavir therapy. Test-positive patients should not receive the drug.
--Because of an increased risk of HIV-associated nephropathy, baseline urinalysis and creatinine clearance testing should be considered, particularly in black patients.
--Clinicians should put greater emphasis on adherence to the full HIV care plan, rather than focus solely on adherence to medications.
--Patient management should include monitoring for all relevant age- and gender-specific health problems.

To optimize patient adherence, the authors advise that, if possible, HIV care sites should provide care that is linguistically and culturally appropriate and competent. Each patient should have a primary provider, and patients should be evaluated for depression and substance abuse. If present, a management plan to address these problems should be implemented.

Reference:
Clin Infect Dis 2009;49:651-681.

Views: 3836
Rating:

HIV-infected women often neglect cervical cancer screening

2009-07-30T14:05:26+01:00

NEW YORK (Reuters Health) - Even though they are at increased risk of invasive cervical cancer, nearly one in four HIV-positive women in the US who were recently interviewed had not undergone a Pap test in the previous year, investigators report.

“The risk of cervical cancer has not decreased since the introduction of (highly active antiretroviral) therapy, highlighting the continued importance of cervical cancer screening in this population,” the research team at the US Centers for Disease Control and Prevention comments in the Journal of Acquired Immune Deficiency Syndromes for August 1.

To see if guidelines for annual cervical cancer screening for this population were being performed, Dr. Alexandra M. Oster and associates used data from the Supplement to HIV/AIDS Surveillance project. Included were 2417 adult women in 18 states.

Records showed that 23% of those interviewed had not undergone a Pap test during the year before the interview.

Increasing age (adjusted odds ratio (AOR) 1.3 per 10 years) was an independent predictor of not being tested, as was the most recent CD4 count being less than 200 cells/mL (AOR 2.1), compared with a higher CD4 count.

“Because of competing priorities,” the authors suspect that preventive care for women with low CD4 counts “may be given lower priority than in other HIV-infected women. However, it is important to remember that these women are at higher risk of HPV infection and abnormal Pap test findings; thus, cervical cancer screening should be a high priority.”

Other factors that decreased the likelihood of missing a Pap test over the previous year were a history of abnormal Pap test findings (AOR = 0.6), and being pregnant (AOR 0.6) or having a sexually transmitted disease (AOR 0.4) during the previous year.

Dr. Oster’s group also observed that 45% of the subjects had their most recent pelvic exam at their usual source of HIV care, which reduced the likelihood that they had a Pap test. The highest AOR of not receiving a Pap test associated with this factor was for Hispanic women (4.8), following by white women (2.3), African American women (1.7), and women of other races (2.1)

“Integrating HIV and gynecologic care and educating clinicians about recommendations may increase screening,” Dr. Oster and associates suggest.

Reference:
J Acquir Immune Defic Synder 2009;51:430-436.

Views: 3341
Rating:

Single-tablet daily ART regimen maintains high rate of HIV-1 suppression

2009-07-08T14:10:17+01:00

NEW YORK (Reuters Health) – In a prospective, randomized trial, a single daily tablet containing efavirenz, emtricitabine, and tenofovir (Atripla; Bristol Myers Squibb & Gilead Sciences LLC) maintained viral suppression in HIV-1 infected patients as well as the standard multiple-pill regimen.

The report of the study, published in the June 1st Journal of the Acquired Immune Deficiency Syndrome, notes that at baseline, all 300 participants were on stable antiretroviral therapy (ART) regimens, with viral loads of less than 200 copies/mL for at least 3 months. Their mean CD4 count was 540 cells/µL, and 96% of subjects had HIV-1 RNA <50 copies/mL.

Before enrollment in the trial, 53% were on protease-inhibitor ART and 47% were on non-nucleoside reverse transcriptase inhibitor-based regimens. On randomization, 203 were assigned to the Atripla regimen while 97 remained on their baseline regimen. The entire 48-week study was completed by 266 patients.

In the intent-to-treat analysis, Dr. Edwin DeJesus, of the Orlando Immunology Center in Florida, and colleagues found that at 48 weeks, the primary endpoint -- HIV-1 RNA below 200 copies/mL -- had been achieved by 89% of the patients in the single-tablet group versus 88% of those on unmodified antiretroviral regimens, “indicating noninferiority” of the newer approach.

Similarly, there was no significant difference between groups in maintenance of viral load below 50 copies/mL and no significant changes in CD4 cell counts within or between the two arms of the study.

Discontinuation rates were similar between the groups, but more patients in the single-tablet group discontinued due to adverse events, “most commonly for nervous system symptoms,” according to the investigators. Patients who formerly took protease inhibitor-based ART were more likely to experience these side effects.

Three patients in the single-tablet group and one in the control group had virologic failure.

“In summary,” the researchers conclude, “patients who were stable and virologically suppressed while receiving a wide array of non-nucleoside reverse transcriptase inhibitor- and protease inhibitor-based antiretroviral regimens and had their treatment simplified to a single-tablet regimen of efavirenz, emtricitabine, and tenofovir maintained high rates of virologic suppression compared to those who continued their regimen unmodified.”

Reference:
J Acquir Immune Defic Syndr 2009;51:163-174.

Views: 3897
Rating: