Low body weight and type of protease inhibitor predict discontinuation and treatment-limiting adverse drug reactions among HIV-infected patients starting a protease inhibitor regimen: consistent results from a randomized trial and an observational cohort

Decreasing rate of multiple treatment modifications among individuals who initiated antiretroviral therapy in 1997-2009 in the Danish HIV Cohort Study

BACKGROUND

We hypothesized that rates and reasons for treatment modifications have changed since the implementation of combination antiretroviral therapy (cART) due to improvements in therapy.

METHODS

From a nationwide population-based cohort study we identified all HIV-1-infected adults who initiated cART in Denmark 1997-2009 and were followed ≥1 year. Incidence rate ratios (IRRs) and reasons for treatment modifications were estimated and compared between patients, who initiated treatment in 1997-1999, 2000-2004 and 2005-2009. Rates of discontinuation of individual antiretroviral drugs (ARVs) were evaluated.

RESULTS

A total of 3,107 patients were followed for a median of 7.3 years (IQR 3.8-10.8). Rates of first treatment modification ≤1 year after cART initiation did not change (IRR 0.88 [95% CI 0.78, 1.01] and 1.03 [95% CI 0.90, 1.18] in 2000-2004 and 2005-2009, respectively, compared with 1997-1999). Rates of multiple modifications decreased markedly (2000-2004 IRR 0.60 [95% CI 0.53, 0.67] and 2005-2009 IRR 0.38 [95% CI 0.32, 0.46]). Rates of treatment modifications due to virological failure, toxicity and other/unknown reasons decreased (IRR 0.25 [95% CI 0.14, 0.45], 0.69 [95% CI 0.56, 0.83] and 0.45 [95% CI 0.36, 0.57], respectively, in 2005-2009 compared with 1997-1999), whereas the rate of modifications with the aim of simplification increased (IRR 1.85 [95% CI 1.52, 2.25]).

CONCLUSIONS

Rates of first treatment modification ≤1 year after cART initiation have not changed since the early cART era, whereas the risk of multiple modifications has decreased markedly. Modifications due to virological failure and toxicity have decreased substantially, whereas rates of switch to simpler and less toxic regimens have increased.

Antiretroviral treatment changes in adults from Côte d'Ivoire: the roles of tuberculosis and pregnancy

OBJECTIVE

To determine the rates and causes of first antiretroviral treatment changes in HIV-infected adults in Côte d'Ivoire.

METHODS

We evaluated adults who initiated antiretroviral treatment in an outpatient clinic in Abidjan. We recorded baseline and follow-up data, including drug prescriptions and reasons for changing to alternative first-line regimens (drug substitution for any reason but failure) or second-line regimens (switch for failure).

RESULTS

Two thousand and twelve HIV-infected adults (73% women) initiated antiretroviral treatment. At baseline, 9% of all patients were on treatment for tuberculosis and 3% of women were pregnant. First-line antiretroviral treatment consisted of two nucleoside reverse transcriptase inhibitors (58% stavudine-lamivudine, 42% zidovudine-lamivudine) and efavirenz (63%), nevirapine (32%) or indinavir (5%). Median follow-up time was 16.9 months. During this time, 205 (10%) patients died and 261 (13%) were lost to follow-up. Overall, the rate of treatment modifications was 20.7/100 patient-years. The most common modifications were drug substitutions for intolerance (12.4/100 patient-years), pregnancy (4.5/100 patient-years) and tuberculosis (2.5/100 patient-years). The rates of intolerance-related substitutions were 17.9/100 patient-years for stavudine, 6.3/100 patient-years for nevirapine, 3.9/100 patient-years for zidovudine and 0.1/100 patient-years for efavirenz. Twenty percent of efavirenz substitutions resulted from pregnancy and 18% of nevirapine substitutions were related to tuberculosis treatment.

CONCLUSION

During the first months following antiretroviral treatment initiation, a third of all treatment changes occurred for reasons other than intolerance to the drug or treatment failure. In Africa, drug forecasting is crucial to ensuring the success of HIV treatment programmes. Drugs that do not require interruptions during pregnancy or tuberculosis treatment should be made more readily available as first-line drugs in sub-Saharan Africa.

Unmeasured confounding caused slightly better response to HAART within than outside a randomized controlled trial

OBJECTIVE

To compare the outcome of highly active antiretroviral therapy (HAART) in HIV-infected patients initiating equivalent regimens within and outside a randomized controlled trial (RCT).

STUDY DESIGN AND SETTING

The Danish Protease Inhibitor Study (DAPIS) was a national multicenter RCT comparing initial treatment with indinavir, ritonavir, or saquinavir/ritonavir during 96 weeks. From the Danish HIV Cohort Study we identified all patients initiating one of these protease-inhibitor-based HAART regimens: 425 patients within DAPIS and 677 outside the trial. We compared viral load, CD4 count response, and mortality.

RESULTS

At weeks 96 and 240, trial participants were more likely than nonparticipants to have undetectable viral load (adjusted odds ratio [adOR] 1.28 [95% CI=0.94-1.74] and 1.70 [95% CI=1.16-2.50]) and a CD4 increase > or =100 cells/microl (adOR 1.37 [95% CI=1.03-1.82] and 1.53 [95% CI=1.04-2.25]). For antiretroviral-experienced, but not for antiretroviral-naïve patients, trial participants had a lower risk of death (mortality rate ratio [MRR]=0.46 [95% CI=0.27-0.77]) than nonparticipants. This effect was moderated in adjusted analyses (MRR=0.60 [0.33-1.07]).

CONCLUSIONS

Compared to nontrial patients, trial participants had better response to HAART. The differences were small defying the notion that results obtained in RCTs are unachievable in routine clinical practice.

Indinavir Trough Concentration as a Determinant of Early Nephrolithiasis in HIV-1-Infected Adults

Indinavir plasma levels are associated with antiretroviral efficacy; however, little data are available regarding toxicity. We assessed the relationship between indinavir pharmacokinetic (PK) characteristics and severe nephrolithiasis as well as other severe or serious adverse reactions. Patients included in the ANRS CO8 APROCO-COPILOTE cohort and receiving 800 mg indinavir three times daily as a first-line protease inhibitor were eligible for this study. To be included in the analysis, their plasma sample at month 1 (M1) had to be available (n = 282) to estimate using population PK modeling, indinavir PK characteristics, ie, maximum (Cmax) and trough plasma (Cres) concentrations, area under the curve (AUC), and observed/predicted concentration ratio (CR). A Cox model was used to estimate the independent effect of Cmax, Cres, AUC, and CR on the hazard of severe nephrolithiasis and serious adverse reactions. At M1, median Cmax was 6205 ng/mL, Cres 631 ng/mL, AUC 24,242 ng . h/mL, and CR 0.6. After a median follow up of 12 months, 11% of patients (30 of 282) had experienced at least one serious adverse reaction among which 12 were nephrolithiasis. In the multivariate analyses, early high indinavir Cres (ie, >/=1000 ng/mL at M1) was associated with a higher rate of severe nephrolithiasis (hazard ratio = 6.7; 95% confidence interval = 1.8-25.2; P < 0.01) and was also associated with a higher rate of all serious adverse reactions but only when nephrolithiasis were included among those cases. Prospective and early indinavir Cres determination should be recommended in the patient's care management and dosage adjustments.

Interruption of combination antiretroviral therapy and risk of clinical disease progression to AIDS or death

OBJECTIVES

The aim of the study was to compare incidence rates (IRs) of AIDS/death in patients with and without treatment interruption (TI) of combination antiretroviral therapy (cART) for periods of 3 months or more for different categories of CD4 cell count and viral load, and to determine risk factors for clinical progression to AIDS/death.

METHODS

Patients starting cART with a CD4 cell count and a viral load available within 6 months of starting cART were included in the study. The IR and risk factors of TI were determined. We assessed the incidence rate ratios (IRRs) for TI and AIDS/death events using Poisson regression models.

RESULTS

Of 3811 patients included in the study, 26% were ART-naïve prior to cART. The median date of starting cART was July 1997, the median CD4 cell count was 226 cells/microL and the median viral load was 4.36 log(10) HIV-1 RNA copies/mL. We observed 1243 interruptions and 403 AIDS-events/deaths. The IR of AIDS/death was higher in patients with lower CD4 cell counts or higher viral loads, regardless of TI. After adjusting for baseline factors, the IR of AIDS/death was significantly higher in the TI group than in the non-TI group [IRR 2.63; 95% confidence interval (CI) 2.01-3.44; P<0.0001]; this could be explained by current CD4 cell counts and viral loads, as the CD4 cell count- and viral load-adjusted IRR was 1.14 (95% CI 0.86-1.51; P=0.37). Within the TI group, patients with a current CD4 cell count of <200 cells/microL had a 3-fold higher risk of AIDS/death than those with a CD4 cell count of 200-350 cells/microL, whereas patients with a current CD4 cell count of >350 cells/microL had a 4-fold lower risk of disease progression.

CONCLUSIONS

TI is common in clinical practice. The risk of AIDS/death increased more than 2-fold for patients stopping all cART regimen drugs for 3 months or more. Among patients experiencing a TI, those with low CD4 cell counts, high viral loads or prior AIDS had an increased risk of AIDS/death. Hence, TI should be discouraged and closely monitored if it occurs.

Reasons for stopping antiretrovirals used in an initial highly active antiretroviral regimen: increased incidence of stopping due to toxicity or patient/physician choice in patients with hepatitis C coinfection

Low adherence and toxicities among HIV-positive patients starting highly active antiretroviral therapy (HAART) can lead to discontinuation of therapy and treatment failure. Little is known about hepatitis C (HCV) status and discontinuation of HAART. Poisson regression was used to determine factors related to discontinuation of any part of an initial HAART regimen due to treatment failure (TF) or toxicities and patient/physician choice (TOX), and to investigate the relationship between HCV and discontinuation of a HAART regimen in 1198 patients staring HAART after 1999 from the EuroSIDA study. At 1 year after starting HAART, 70% of patients remained on their original regimen, 24% had changed, and 6% were off all treatment. The most frequent reason for discontinuation was toxicities (30.4%). There was no change over time in the proportion of patients discontinuing after stratification by reason for discontinuation (p = 0.18). Of patients 190 stopped at least one antiretroviral drug used in their initial HAART regimen due to toxicities; the toxicity reported did not vary according to HCV status (p = 0.90). Anti-HCV seropositive patients had a higher incidence of discontinuation due to TOX (IRR 1.46, 95% CI 1.13-1.88, p = 0.0042) compared to patients without HCV. Patients with HCV were more likely to discontinue all or part of their HAART regimens due to toxicity or patient/physician choice. Managing adverse events must remain a key intervention in maintaining HAART. There is a need for further studies to describe the relationship between HCV, specific antiretrovirals, and different treatment strategies.

Lipodystrophy-associated symptoms and medication adherence in HIV/AIDS

Lipodystrophy-associated manifestations remain a challenge for persons infected with HIV disease and their care providers. Symptomatic HIV disease and side effects of medications are implicated in antiretroviral medication nonadherence. This study examined the relationship between time since initial diagnosis with HIV, presence and type of lipodystrophic symptoms, and adherence to medication regimens in persons with HIV/AIDS. Using a cross-sectional, descriptive design, the sample was composed of 165 persons from three outpatient HIV settings in Boston, Massachusetts; Fresno, California; and Victoria, Texas. Participants completed a questionnaire comprised of sociodemographic questions, adherence scales, quality-of-life scales, and open-ended questions regarding presence and types of lipodystrophy-associated symptoms, and how these physical changes made them feel. Adherence was moderate with a mean score of 1.44 (standard deviation [SD] +/- 1.33) on the Morisky Medication Adherence Scale (MMAS). The MMAS is a Likert-type scale ranging from 0-4, with "0" indicating very adherent. This finding indicated that the participants took their medications moderately well despite self-reports of significant numbers of HIV disease and treatment-related body fat changes. Time since initial diagnosis was 8.86 +/- 5.55 years and was not related to adherence. Nor did the type of lipodystrophic symptoms affect adherence. Quality of life however, was significantly related to adherence suggesting an approach that might be taken to improve adherence.

Reasons for stopping antiretrovirals used in an initial highly active antiretroviral regimen: increased incidence of stopping due to toxicity or patient/physician choice in patients with hepatitis C coinfection

Low adherence and toxicities among HIV-positive patients starting highly active antiretroviral therapy (HAART) can lead to discontinuation of therapy and treatment failure. Little is known about hepatitis C (HCV) status and discontinuation of HAART. Poisson regression was used to determine factors related to discontinuation of any part of an initial HAART regimen due to treatment failure (TF) or toxicities and patient/ physician choice (TOX), and to investigate the relationship between HCV and discontinuation of a HAART regimen in 1198 patients staring HAART after 1999 from the EuroSIDA study. At 1 year after starting HAART, 70% of patients remained on their original regimen, 24% had changed, and 6% were off all treatment. The most frequent reason for discontinuation was toxicities (30.4%). The incidence of any discontinuation was significantly lower after 1999 compared to before [incidence rate ratio (IRR) 0.43; 95% CI 0.35-0.53, p < 0.0001], this pattern was most marked for toxicities (IRR 0.28; 95% CI 0.20-0.39, p < 0.0001) and patient/physician choice (IRR 0.49; 95% CI 0.33-0.73, p < 0.0001). Patients with HCV had a higher incidence of discontinuation due to TOX (IRR 1.46, 95% CI 1.13-1.88, p = 0.0042) compared to patients without HCV. Patients with HCV were more likely to discontinue all or part of their HAART regimens due to toxicity or patient/physician choice. Managing adverse events must remain a key intervention in maintaining HAART. There is a need for further studies to describe the relationship between HCV, specific antiretrovirals, and different treatment strategies.

The Relationship between Cd4 Cell Count Nadirs and the Toxicity Profiles of Antiretroviral Regimens

Background

It has been suggested that a lower pre-highly active antiretroviral therapy (HAART) CD4 count nadir may lead to a greater risk of experiencing HAART-related toxicity. We investigated the relationship between the pre-HAART CD4 count nadir, HAART and the occurrence of laboratory-defined toxicities.

Methods

Previously antiretroviral-naive individuals starting HAART at the Royal Free Hospital, London, UK, were included. Drug discontinuation, increases in total cholesterol (by >1mmol/l), alanine aspartate transferase/ alanine aminotransferase (AST/ALT) (by >2.5 times the upper limit of normal), bilirubin (by >2.5 times the upper limit of normal), triglycerides (by >1 mmol/l) and decreases in haemoglobin (by >2 g/dl) were assessed.

Results

377/847 (45%) individuals starting HAART stopped at least one antiretroviral within the first 48 weeks. Lower CD4 nadirs were not associated with a greater rate of discontinuing antiretrovirals (adjusted hazard ratio (HR)=1.04 per 100 cells/mm3 higher; 95% confidence intervals (CI) 0.99–1.10; P=0.15). 70/297 (24%), 39/192 (20%) and 73/358 (20%) with a CD4 cell nadir of 0–100, 100–200 and 200+ cells/mm3, respectively, stopped for toxicity reasons; 11/297 (4%), 5/192 (3%) and 3/358 (1%) stopped for reasons of insufficient efficacy; 63/297 (21%), 33/192 (17%) and 80/358 (22%) stopped for other reasons ( P=0.1). Reasons for stopping were similar between CD4 nadir groups. Lower CD4 nadirs were not associated with an increased risk of hypercholesterolaemia, anaemia, hypertriglyceridaemia or increases in AST/ALT but were associated with increased incidence of hyperbilirubinaemia (HR=0.67 per 100 cells/mm3 higher; 95% CI 0.49–0.92; P=0.01).

Discussion

Lower CD4 nadirs were not found to be associated either with discontinuing an antiretroviral or with a higher risk of toxicity, except for an increased risk of experiencing an increase in bilirubin levels.

Incidence of and risk factors for adverse drug reactions in a prospective cohort of HIV-infected adults initiating protease inhibitor-containing therapy

Risk factors associated with the occurrence of protease inhibitor (PI)-related severe and serious adverse drug reactions (SADRs) were analyzed in a prospective cohort of 1155 patients who initiated PI-containing therapy. During a total follow-up of 2037 patient-years, 169 SADRs were reported, yielding a rate of 8 incidents per 100 patient-years (95% confidence interval [CI], 6.8-8.6). The most frequent SADRs were elevated transaminase levels (in 49 events); renal colic (27); abnormal hematological findings (23); and metabolic (18), neuromuscular (7), pancreatic (6), cutaneous (6), cardiovascular (5), and psychiatric disorders (5). Among baseline characteristics, plasma human immunodeficiency virus RNA levels of >or=5 log(10) copies/mL (hazard ratio [HR], 1.5; 95% CI, 1.1-2.2), elevated aspartate aminotransferase levels (HR, 1.1 for each 20 IU of elevation; 95% CI, 1.1-1.2), creatinine clearance levels of <70 mL/min (HR, 2.1; 95% CI, 1.2-3.7), test results positive for hepatitis C virus antibodies or hepatitis B surface antigenemia (HR, 2.6; 95% CI, 1.8-3.7), and receipt of indinavir (HR, 1.7; 95% CI, 1.2-2.4) were independently predictive of a SADR. SADRs were frequent in the first 4 months after initiation of highly active antiretroviral therapy but continued to occur after that time period.

Trends in the use of highly active antiretroviral therapy in western Denmark 1996-2000

New antiretroviral drugs, expanding knowledge of their long-term toxic effects and the large number of patients with treatment failure have increased the demand for new strategies in the antiretroviral treatment of HIV-infected patients. The present study was conducted as part of the HIV Cohort Study in western Denmark to reveal trends in the use of antiretrovirals in the region. The cohort includes all patients attached to those centers treating HIV patients in western Denmark. A total of 537 patients who started highly active antiretroviral therapy (HAART) were included. The number of patients receiving HAART increased dramatically in 1996 and 1997 before leveling off, with 45-75 patients initiating treatment annually thereafter. Median follow-up time after initiation of HAART was 151 weeks. An estimated 45.1% of patients had the initial HAART regimen modified during the first year of follow-up. Side-effects and treatment failure were the main reasons for treatment modifications. Major new strategies implemented in the region in 1999 and 2000 included treatment with boosted protease inhibitors and non-nucleoside reverse transcriptase inhibitors.

Analysis of Virological Efficacy in Trials of Antiretroviral Regimens: Drawbacks of Not Including Viral Load Measurements after Premature Discontinuation of Therapy

Objectives

To compare two analytic approaches to assess the virological effect of HAART according to the intention-to-treat (ITT) principle.

Material

Data from 2318 patients enrolled in 10 randomised clinical trials (RCTs) and from 3091 patients followed in an observation cohort (EuroSIDA) starting their first HAART regimen.

Methods

Two classifications of defining virological response 48 weeks after starting the therapy to be evaluated were compared: 1) only patients remaining on the therapy and having a plasma viral load (pVL) below a given cut-off level at week 48 were classified as responders (ITT/s=f); and 2) patients with a pVL below a given cut-off at week 48 whether they remained on initial assigned therapy or switched therapy were responders (ITT/s incl). In both analyses, patients with missing data at week 48 were classified as failures (i.e., non-responders).

Results

According to ITT/s=f, 22–70% of the patients starting a HAART regimen in a RCT experienced a virological response at week 48. Only two RCTs had complete follow-up data ( n=424): between 29 and 62% achieved a virological response at week 48 in the six treatment arms evaluated in the studies according to ITT/s=f, and 41–72% according to ITT/s incl. Among those who discontinued the therapy to be evaluated in these two trials, 13–45% (cohort: 39–74%) subsequently experienced a virological response at week 48. The subsequent response rates were associated with the reason for discontinuation (toxicity versus confirmed virological failure: 63 vs 33%), varied largely across regimens and were not associated with the discontinuation rate.

Conclusions

Discontinuation of follow-up at switch from the therapy to be evaluated remains common in anti-retroviral treatment trials, but leads to an imprecise and incomplete assessment of the intrinsic effect of a given regimen. Complete follow-up of all patients should be encouraged strongly as this will allow for several complementary analytic approaches and a focus on optimal treatment strategies rather than specific regimens.