Acceptance and tolerability of an adjuvanted nH1N1 vaccine in HIV-infected patients in the Cologne-Bonn cohort

Objective

To evaluate the acceptance and tolerability of the nH1N1 2009 vaccine in HIV-positive individuals.

Method

758 patients were included in this prospective study. Different study populations were formed: The Tolerability Study Group consists of HIV-infected patients who visited three outpatient clinics (Cologne, Bonn, Freiburg) during a predefined time period. Patients were offered nH1N1 vaccination. Those accepting were administered a standard dose AS03 adjuvant nH1N1 vaccine. Questionnaires to report side effects occurring within 7 days after immunization were handed out.

In a substudy conducted during the same time period, acceptance towards immunization was recorded. This Acceptance Study Group consists of all HIV-infected patients visiting the Cologne clinic. They were offered vaccination. In case of refusal, motivation was recorded.

Results

In the Tolerability Study Group, a total of 475 patient diaries returned in the three study centres could be evaluated, 119 of those (25%) reported no side effects. Distribution of symptoms was as follows: Pain 285/475 patients (60%), swelling 96 (20%), redness 54 (11%), fever 48/475 (10%), muscle/joint ache 173 (36%), headache 127 (27%), and fatigue 210 (44%). Association of side effects with clinical data was calculated for patients in Cologne and Bonn. Incidence of side effects was significantly associated with CDC stages A, B compared to C, and with a detectable viral load (> 50 copies/mL). No correlation was noted for CD4 cell count, age, gender or ethnicity.

In the Acceptance Study Group, 538 HIV-infected patients were offered vaccination, 402 (75%) accepted, while 136 (25%) rejected. Main reasons for rejection were: Negative media coverage (35%), indecisiveness with preference to wait until a later date (23%), influenza not seen as personal threat (19%) and scepticism towards immunization in general (10%).

Conclusion

A total of 622 HIV-infected patients were vaccinated against nH1N1-influenza in the three study centres. No severe adverse events were reported. The tolerability was in most parts comparable to general population. Acceptance rate towards influenza vaccination was high (75%). Those refusing the immunization mentioned negative media coverage as the major influence on their decision.

[HIV infection: a chronic disease with new challenges]

The treatment of cardiovascular, metabolic and malignant diseases is playing an increasing role in HIV-infected patients. Intensified cancer screening is recommended, but data demonstrating a reduction of tumour incidence or tumour-associated mortality are rare. Controversy exists about the best time point of initiation of antiretroviral therapy. Recently, data indicate that an earlier start could reduce HIV transmission.

Integration of population pharmacokinetics and pharmacogenetics: an aid to optimal nevirapine dose selection in HIV-infected individuals

BACKGROUND

Nevirapine is metabolized by CYP2B6 and polymorphisms within the CYP2B6 gene partly explain inter-patient variability in pharmacokinetics. The aim of this study was to model the complex relationship between nevirapine exposure, weight and genetics (based on combined analysis of CYP2B6 516G > T and 983T > C single nucleotide polymorphisms).

METHODS

Non-linear mixed-effects modelling was used to estimate pharmacokinetic parameters from 275 patients. Simulations of the nevirapine concentration profile were performed with dosing regimens of 200 mg twice daily and 400 mg once daily for individuals with body weights of 50, 70 and 90 kg in combination with CYP2B6 genetic variation.

RESULTS

A one-compartment model with first-order absorption best described the data. Population clearance was 3.5 L/h with inter-patient variability of 24.6%. 516T homozygosity and 983C heterozygosity were associated with 37% and 40% lower clearance, respectively. Body weight was the only significant demographic factor influencing clearance, which increased by 5% for every 10 kg increase. For individuals with higher body weight, once-daily nevirapine was associated with a greater risk of sub-therapeutic drug exposure than a twice-daily regimen. This risk was offset in individuals who were 516T homozygous or 983C heterozygous in which drug exposure was optimal for  >  95% of patients with body weight of ≤ 70 kg.

CONCLUSIONS

The data suggest that a 400 mg once-daily dose could be implemented in accordance with CYP2B6 polymorphism and body weight. However, the use of nevirapine once daily (immediate release; off-label) in the absence of therapeutic drug monitoring is not recommended due to the risk of inadequate exposure to nevirapine in a high proportion of patients. There are different considerations for the extended-release formulation (nevirapine XR) that demonstrate minimal peak-to-trough fluctuations in plasma nevirapine levels.

HIV prevalence and route of transmission in Turkish immigrants living in North-Rhine Westphalia, Germany

The high number of Turkish immigrants in the German state North-Rhine Westphalia (NRW) compelled us to look for HIV-infected patients with Turkish nationality. In the AREVIR database, we found 127 (107 men, 20 women) Turkish HIV patients living in NRW. In order to investigate transmission clusters and their correlation to gender, nationality and self-reported transmission mode, a phylogenetic analysis including pol gene sequences was performed. Subtype distribution and the number of HIV drug resistance mutations in the Turkish patient group were found to be similar to the proportion in the non-Turkish patients. Great differences were observed in self-reported mode of transmission in the heterosexual Turkish male subgroup. Neighbour-joining tree of pol gene sequences gave indication that 59% of these reported heterosexual transmissions cluster with those of men having sex with men in the database. This is the first study analysing HIV type distribution, drug resistance mutations and transmission mode in a Turkish immigrant population.

CCR5 antibodies HGS004 and HGS101 preferentially inhibit drug-bound CCR5 infection and restore drug sensitivity of Maraviroc-resistant HIV-1 in primary cells

R5 HIV-1 strains resistant to the CCR5 antagonist Maraviroc (MVC) can use drug-bound CCR5. We demonstrate that MVC-resistant HIV-1 exhibits delayed kinetics of coreceptor engagement and fusion during drug-bound versus free CCR5 infection of cell lines. Antibodies directed against the second extracellular loop (ECL2) of CCR5 had greater antiviral activity against MVC-bound compared to MVC-free CCR5 infection. However, in PBMCs, only ECL2 CCR5 antibodies HGS004 and HGS101, but not 2D7, inhibited infection by MVC resistant HIV-1 more potently with MVC-bound than with free CCR5. In addition, HGS004 and HGS101, but not 2D7, restored the antiviral activity of MVC against resistant virus in PBMCs. In flow cytometric studies, CCR5 binding by the HGS mAbs, but not by 2D7, was increased when PBMCs were treated with MVC, suggesting MVC increases exposure of the relevant epitope. Thus, HGS004 and HGS101 have antiviral mechanisms distinct from 2D7 and could help overcome MVC resistance.

Two-year safety and virologic efficacy of maraviroc in treatment-experienced patients with CCR5-tropic HIV-1 infection: 96-week combined analysis of MOTIVATE 1 and 2

BACKGROUND

Maraviroc, the first approved CCR5 antagonist, demonstrated 48-week safety and virologic efficacy in CCR5-tropic HIV-infected, treatment-experienced patients; however, critical longer-term safety and durability of responses are unknown.

METHODS

Two-year follow-up of 2 prospective, randomized, blinded studies of maraviroc once daily or twice daily, or placebo in treatment-experienced patients with R5-tropic HIV-1 receiving an optimized background regimen. Unblinding occurred after the week-48 visit of the last enrolled patient. Safety and virologic parameters were assessed through week 96.

RESULTS

One thousand forty-nine patients were randomized and received study drugs. HIV-1 RNA was <50 copies per milliliter at week 96 in 39% and 41% of patients receiving maraviroc every day or twice a day, respectively. Among patients with HIV-1 RNA <50 copies per milliliter at week 48, 81% and 87% of patients receiving maraviroc every day or twice a day, respectively, maintained this response at week 96. At week 96, median CD4+ T-cell counts increased from baseline by 89 and 113 cells per cubic millimeter with maraviroc every day and twice a day, respectively. Exposure-adjusted rates of adverse events were similar with maraviroc or placebo. No new or unexpected events were observed after week 48.

CONCLUSIONS

Maraviroc-containing antiretroviral regimens maintained durable responses in treatment-experienced patients with R5 HIV-1 through 96 weeks of treatment with a safety profile similar to placebo.

Clinical outcome of HIV-infected patients with discordant virological and immunological response to antiretroviral therapy

BACKGROUND

A subgroup of human immunodeficiency virus type 1 (HIV-1)-infected patients with severe immunodeficiency show persistently low CD4+ cell counts despite sustained viral suppression. It is unclear whether this immuno-virological discordance translates into an increased risk for clinical events.

METHODS

Data analysis from a large multicenter cohort incorporating 14,433 HIV-1-infected patients in Germany. Treatment-naive patients beginning antiretroviral therapy (ART) with CD4+ cell counts <200 cells/μL who achieved complete and sustained viral suppression <50 copies/mL (n = 1318) were stratified according to the duration of immuno-virological discordance (failure to achieve a CD4+ cell count ≥200 cells/μL). Groups were compared by descriptive and Poisson statistics. The time-varying discordance status was analyzed in a multivariable Cox model.

RESULTS

During a total of 5038 person years of follow-up, 42 new AIDS events occurred. The incidence rate of new AIDS events was highest in the initial 6 months of complete viral suppression (immuno-virological discordance group, 55.06; 95% confidence interval [CI], 30.82-90.82; and immune responder group, 24.54; 95% CI, 10.59-48.35) and decreased significantly by 65% per year in patients with immuno-virological discordance (incidence risk ratio, 0.35; 95% CI, 0.14-0.92; P = .03). Immuno-virological discordance and prior AIDS diagnosis were independently associated with new AIDS events (hazard ratio, 3.10; 95% CI, 1.09-8.82; P = .03).

CONCLUSION

Compared with immune responders, patients with immuno-virological discordance seem to remain at increased risk for AIDS. Absolute risk is greatly reduced after the first 6 months of complete viral suppression.

Prevalence and characteristics of hepatitis B and C virus infections in treatment-naïve HIV-infected patients

In HIV-infected treatment-naïve patients, we analyzed risk factors for either chronic hepatitis B (HBV) infection, occult HBV infection (OHBV) or a positive hepatitis C (HCV) serostatus. A total of 918 patients of the RESINA-cohort in Germany were included in this study. Before initiating antiretroviral therapy, clinical parameters were collected and blood samples were analyzed for antibodies against HIV, HBV and HCV, HBs antigen and viral nucleic acids for HIV and HBV. Present or past HBV infection (i.e. HBsAg and/or anti-HBc) was found in 43.4% of patients. HBsAg was detected in 4.5% (41/918) and HBV DNA in 6.1% (34/554), resulting in OHBV infection in 2.9% (16/554) of patients. OHBV infection could not be ruled out by the presence of anti-HBs (50.1%) or the absence of all HBV seromarkers (25%). A HCV-positive serostatus was associated with the IVDU transmission route, non-African ethnicity, elevated liver parameters (ASL or GGT) and low HIV viral load. Replicative HBV infection and HCV-positive serostatus both correlated with HIV resistance mutations (P = 0.001 and P = 0.028). HBV and HCV infection are frequent co-infections in HIV treatment-naive patients. These co-infections influence viral evolution, clinical parameters and serological markers. Consequently, HIV patients should routinely be tested for HBV and HCV infection before initiating HIV treatment. OHBV infection constituted almost half of all HBV infections with detectable HBV DNA. Due to a lack of risk factors indicating OHBV infection, HBV diagnosis should not only include serological markers but also the detection of HBV DNA.

A comparison of the long-term durability of nevirapine, efavirenz and lopinavir in routine clinical practice in Europe: a EuroSIDA study

OBJECTIVES

The durability of combination antiretroviral therapy (cART) regimens can be measured as time to discontinuation because of toxicity or treatment failure, development of clinical disease or serious long-term adverse events. The aim of this analysis was to compare the durability of nevirapine, efavirenz and lopinavir regimens based on these measures.

METHODS

Patients starting a nevirapine, efavirenz or lopinavir-based cART regimen for the first time after 1 January 2000 were included in the analysis. Follow-up started ≥ 3 months after initiation of treatment if viral load was <500 HIV-1 RNA copies/mL. Durability was measured as discontinuation rate or development/worsening of clinical markers.

RESULTS

A total of 603 patients (21%) started nevirapine-based cART, 1465 (51%) efavirenz, and 818 (28%) lopinavir. After adjustment there was no significant difference in the risk of discontinuation for any reason between the groups on nevirapine and efavirenz (P=0.43) or lopinavir (P=0.13). Compared with the nevirapine group, those on efavirenz had a 48% (P=0.0002) and those on lopinavir a 63% (P<0.0001) lower risk of discontinuation because of treatment failure and a 31% (P=0.01) and 66% (P<.0001) higher risk, respectively, of discontinuation because of toxicities or patient/physician choice. There were no significant differences in the incidence of non-AIDS-related events, worsening anaemia, severe weight loss, increased aspartate aminotransferase (AST)/alanine aminotransferase (ALT) levels or increased total cholesterol. Compared with patients on nevirapine, those on lopinavir had an 80% higher incidence of high-density lipoprotein (HDL) cholesterol decreasing below 0.9 mmol/L (P=0.003), but there was no significant difference in this variable between those on nevirapine and those on efavirenz (P=0.39).

CONCLUSIONS

The long-term durability of nevirapine-based cART, based on risk of all-cause discontinuation and development of long-term adverse events, was comparable to that of efavirenz or lopinavir, in patients in routine clinical practice across Europe who initially tolerated and virologically responded to their regimen.

Plasmacytoid dendritic cells accumulate and secrete interferon alpha in lymph nodes of HIV-1 patients

Circulating plasmacytoid dendritic cells (pDC) decline during HIV-1 infection, but at the same time they express markedly higher levels of interferon alpha (IFNalpha), which is associated with HIV-1 disease progression. Here we show an accumulation of pDC in lymph nodes (LN) of treatment-naïve HIV-1 patients. This phenomenon was associated with elevated expression of the LN homing marker, CCR7, on pDC in peripheral blood of HIV-1 patients, which conferred increased migratory capacity in response to CCR7 ligands in ex vivo functional assays. LN-homed pDC of HIV-1 patients presented higher CD40 and lower BDCA2 levels, but unchanged CD83 and CD86 expression. In addition, these cells expressed markedly higher amounts of IFNalpha compared to uninfected individuals, and were undergoing faster rates of cell death. These results demonstrate for the first time that in asymptomatic, untreated HIV-1 patients circulating pDC up-regulate CCR7 expression, accumulate in lymph nodes, and express high amounts of IFNalpha before undergoing cell death. Since IFNalpha inhibits cell proliferation and modulates immune responses, chronically high levels of this cytokine in LN of HIV-1 patients may impair differentiation and immune function of bystander CD4(+) T cells, thus playing into the mechanisms of AIDS immunopathogenesis.

[Spondylodiscitis - an interdisciplinary challenge]

HISTORY AND ADMISSION FINDINGS

A 21-year-old man presented with severe lumbar back pain and progressive paraparesis with clinical signs of spondylitis. Laboratory findings revealed elevated infectious parameters. Because of a positive Mantoux-Test he had been treated with quadruple tuberculostatic drugs for eight weeks without prior identification of the causative pathogen.

INVESTIGATIONS

Magnetic resonance imaging of the spine revealed a multisegmental spondylitis of the lumbar vertebrae (L3 - L5) with epidural empyema. Computed tomography (CT) of the abdomen confirmed large bilateral abscesses in the psoas muscles.

TREATMENT AND COURSE

The findings supported the diagnosis of spondylitis. The antibiotic regimen was continued. CT-guided drainage was placed in both psoas muscles. Laminectoma of L3 - 5 and dorsal spondylodesis of L2 - S1 were performed immediately. Mycobacterium tuberculosis was cultured from the intraoperative biopsies and treated according to the drug sensitivity test. After further surgical debridment and corporectomy of L4 and L5 the infection was successfully treated. Ten weeks after admission the patient was transferred to a neurologic rehabilitation unit for mobilization.

CONCLUSION

Spondylodiscitis treatment is complex and requires a multidisciplinary approach.

Incidence and risk factors of HIV-related non-Hodgkin's lymphoma in the era of combination antiretroviral therapy: a European multicohort study

BACKGROUND

Incidence and risk factors of HIV-associated non-Hodgkin's lymphoma (NHL) are not well defined in the era of combination antiretroviral therapy (cART).

METHODS

A total of 56,305 adult HIV type-1 (HIV-1)-infected patients who started cART in 1 of 22 prospective studies in Europe were included. Weibull random effects models were used to estimate hazard ratios (HRs) for developing systemic NHL and included CD4(+) T-cell counts and viral load as time-updated variables.

RESULTS

During the 212,042 person-years of follow-up, 521 patients were diagnosed with systemic NHL and 62 with primary brain lymphoma (PBL). The incidence rate of systemic NHL was 463 per 100,000 person-years not on cART and 205 per 100,000 person-years in treated patients for a rate ratio of 0.44 (95% confidence interval [CI] 0.37-0.53). The corresponding incidence rates of PBL were 57 and 24 per 100,000 person-years (rate ratio 0.43, 95% CI 0.25-0.73). Suppression of HIV-1 replication on cART (HR 0.60, 95% CI 0.44-0.81, comparing < or =500 with 10,000-99,999 copies/ml) and increases in CD4(+) T-cell counts (HR 0.30, 0.22-0.42, comparing > or =350 with 100-199 cells/microl) were protective; a history of Kaposi's sarcoma (HR 1.70, 1.08-2.68, compared to no history of AIDS), transmission through sex between men (HR 1.57, 1.19-2.08, compared with heterosexual transmission) and older age (HR 3.71, 2.37-5.80, comparing > or =50 with 16-29 years) were risk factors for systemic NHL.

CONCLUSIONS

The incidence rates of both systemic NHL and PBL were substantially reduced in patients on cART. Timely initiation of therapy is key to the prevention of NHL in the era of cART.

Switch to a raltegravir-based regimen versus continuation of a lopinavir-ritonavir-based regimen in stable HIV-infected patients with suppressed viraemia (SWITCHMRK 1 and 2): two multicentre, double-blind, randomised controlled trials

BACKGROUND

To reduce lipid abnormalities and other side-effects associated with antiretroviral regimens containing lopinavir-ritonavir, patients might want to switch one or more components of their regimen. We compared substitution of raltegravir for lopinavir-ritonavir with continuation of lopinavir-ritonavir in HIV-infected patients with stable viral suppression on lopinavir-ritonavir-based combination therapy.

METHODS

The SWITCHMRK 1 and 2 studies were multicentre, double-blind, double-dummy, phase 3, randomised controlled trials. HIV-infected patients aged 18 years or older were eligible if they had documented viral RNA (vRNA) concentration below the limit of assay quantification for at least 3 months while on a lopinavir-ritonavir-based regimen. 707 eligible patients were randomly allocated by interactive voice response system in a 1:1 ratio to switch from lopinavir-ritonavir to raltegravir (400 mg twice daily; n=353) or to remain on lopinavir-ritonavir (two 200 mg/50 mg tablets twice daily; n=354), while continuing background therapy consisting of at least two nucleoside or nucleotide reverse transcriptase inhibitors. Primary endpoints were the mean percentage change in serum lipid concentrations from baseline to week 12; the proportion of patients with vRNA concentration less than 50 copies per mL at week 24 (with all treated patients who did not complete the study counted as failures) with a prespecified non-inferiority margin of -12% for each study; and the frequency of adverse events up to 24 weeks. Analyses were done according to protocol. These trials are registered with ClinicalTrials.gov, numbers NCT00443703 and NCT00443729.

FINDINGS

702 patients received at least one dose of study drug and were included in the efficacy and safety analyses for the combined trials (raltegravir, n=350; lopinavir-ritonavir, n=352). Percentage changes in lipid concentrations from baseline to week 12 were significantly greater (p<0.0001) in the raltegravir group than in the lopinavir-ritonavir group in each study, yielding combined results for total cholesterol -12.6%vs 1.0%, non-HDL cholesterol -15.0%vs 2.6%, and triglycerides -42.2%vs 6.2%. At week 24, 293 (84.4%, 95% CI 80.2-88.1) of 347 patients in the raltegravir group had vRNA concentration less than 50 copies per mL compared with 319 (90.6%, 87.1-93.5) of 352 patients in the lopinavir-ritonavir group (treatment difference -6.2%, -11.2 to -1.3). Clinical and laboratory adverse events occurred at similar frequencies in the treatment groups. There were no serious drug-related adverse events or deaths. The only drug-related clinical adverse event of moderate to severe intensity reported in 1% or more of either treatment group was diarrhoea, which occurred in ten patients in the lopinavir-ritonavir group (3%) and no patients in the raltegravir group. The studies were terminated at week 24 because of lower than expected virological efficacy in the raltegravir group compared with the lopinavir-ritonavir group.

INTERPRETATION

Although switching to raltegravir was associated with greater reductions in serum lipid concentrations than was continuation of lopinavir-ritonavir, efficacy results did not establish non-inferiority of raltegravir to lopinavir-ritonavir.

FUNDING

Merck.

Effect of baseline CD4 cell counts on the clinical significance of short-term immunologic response to antiretroviral therapy in individuals with virologic suppression

BACKGROUND

Achieving virologic suppression is a clear therapeutic goal for patients receiving combination antiretroviral therapy (cART). However, the effects of immunologic responses, whether measured as CD4 count changes from baseline or CD4 counts at follow-up, in patients with virologic suppression, have not been clearly established.

METHODS

Treatment-naive individuals aged > or =16 years, who initiated cART between 1998 and 2005 in participating cohorts of the ART Cohort Collaboration and achieved viral load < or =400 copies per milliliter 6 months after cART initiation, were included. We used Cox models to examine associations of CD4 change from baseline to 6 months, and absolute CD4 counts at 6 months, with subsequent rates of mortality and AIDS. Analyses were stratified by baseline CD4 count.

RESULTS

Among 23,679 eligible participants, the median increase in CD4 count at 6 months, and the implications of these increases for subsequent mortality and AIDS, varied with baseline CD4 count. Mortality hazard ratios for increases of 0-50 cells per microliter, compared with >100 cells per microliter, were 1.87 (95% confidence interval: 1.28 to 2.73), 1.60 (1.13 to 2.28), 0.98 (0.58 to 1.65) and 1.24 (0.70 to 2.18) in participants with baseline CD4 cell count <50, 50-199, 200-349 and > or =350 cells per microliter, respectively. In contrast, hazard ratios for mortality or AIDS associated with absolute CD4 cell counts at 6 months were similar across all but the highest baseline CD4 cell count strata.

CONCLUSION

It is not possible to derive thresholds for change in CD4 count that define an adequate immunologic response in individuals receiving cART. Absolute CD4 counts at 6 months are a more useful measure of immunologic response and subsequent prognosis.

Mortality of HIV-infected patients starting potent antiretroviral therapy: comparison with the general population in nine industrialized countries

BACKGROUND

Mortality in HIV-infected patients has declined substantially with combination antiretroviral therapy (ART), but it is unclear whether it has reached that of the general population. We compared mortality in patients starting ART in nine countries of Europe and North America with the corresponding general population, taking into account their response to ART.

METHODS

Eligible patients were enrolled in prospective cohort studies participating in the ART Cohort Collaboration. We calculated the ratio of observed to expected deaths from all causes [standardized mortality ratio (SMR)], measuring time from 6 months after starting ART, according to risk group, clinical stage at the start of ART and CD4 cell count and viral load at 6 months. Expected numbers of deaths were obtained from age-, sex- and country-specific mortality rates.

RESULTS

Among 29 935 eligible patients, 1134 deaths were recorded in 131 510 person-years of follow-up. The median age was 37 years, 8162 (27%) patients were females, 4400 (15%) were injecting drug users (IDUs) and 6738 (23%) had AIDS when starting ART. At 6 months, 23 539 patients (79%) had viral load measurements <or=500 copies/ml. The lowest SMR, 1.05 [95% confidence interval (CI) 0.82-1.35] was found for men who have sex with men (MSM) who started ART free of AIDS, reached a CD4 cell count of >or=350 cells/microL and suppressed viral replication to <or=500 copies/ml by the sixth month. In contrast, the SMR was 73.7 (95% CI 46.4-116.9) in IDUs who failed to suppress viral replication and had CD4 cell counts <50 cells/microL at 6 months. The percentage of patients with SMRs <2 was 46% for MSM, 42% for heterosexually infected patients and 0% for patients with a history of injection drug use. Corresponding percentages for SMRs >10 were 4, 14 and 47%.

CONCLUSIONS

In industrialized countries, the mortality experience of HIV-infected patients who start ART and survive the first 6 months continues to be higher than in the general population, but for many patients excess mortality is moderate and comparable with patients having other chronic conditions. Much of the excess mortality might be prevented by earlier diagnosis of HIV followed by timely initiation of ART.

A double-blind, placebo-controlled trial of maraviroc in treatment-experienced patients infected with non-R5 HIV-1

BACKGROUND

Maraviroc, a CCR5 antagonist, is active against R5 but not X4 or dual- or mixed-tropic strains of human immunodeficiency virus type 1 (HIV-1). A phase 2b study was conducted to determine the safety and efficacy of maraviroc in combination with optimized background therapy in treatment-experienced patients infected with dual- or mixed-tropic HIV-1.

METHODS

Treatment-experienced patients with an HIV-1 RNA level 5000 copies/mL who had received 3 classes of drugs and/or were infected with virus resistant to 2 drug classes and were infected with non-R5 HIV-1 were randomized to receive optimized background therapy plus maraviroc (once or twice daily) or placebo. The primary end point was change in HIV-1 RNA level from baseline to 24 weeks.

RESULTS

Among 167 patients infected with dual- or mixed-tropic HIV-1, baseline mean HIV-1 RNA levels were >5 log(10) copies/mL and median CD4(+) cell counts were <50 cells/microL. From baseline to 24 weeks, patients who received placebo demonstrated a mean decrease in HIV-1 RNA levels of 0.97 log(10) copies/mL, compared with mean decreases of 0.91 and 1.20 log(10) copies/mL for those who received maraviroc once (P =.83) or twice (P +.38) daily, respectively. Mean increases in CD4(+) cell counts from baseline were 36 cells/microL for patients who received placebo, 60 cells/microL among patients who received maraviroc once daily, and 62 cells/microL among patients who received maraviroc twice daily. The incidences of serious adverse events were similar among groups.

CONCLUSIONS

In this exploratory study involving extensively treatment-experienced patients with advanced, non-R5 HIV-1 infection, neither superiority nor noninferiority was statistically demonstrated for either maraviroc dosage compared with placebo at 24 weeks of treatment.

TRIAL REGISTRATION

Clinicaltrials.gov identifier NCT00098748 .