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PubMed1998

[Maintenance chemotherapy in the treatment of small cell lung cancer: the advocate's view].

The role of maintenance chemotherapy in the treatment of small cell lung cancer remains controversial. We have collected the arguments in favor of that approach by performing a quantitative and qualitative overview of the studies published on this topic in the French and English literatures since 1980. On the thirteen prospective randomized trials reported, six demonstrated a significant survival advantage in favor of maintenance, no difference was observed in 6 and 1 study had a significant survival advantage for no maintenance. Due to the heterogeneity of the study designs and to the lack of published data, no meta-analysis could be performed. A qualitative overview of the different trials showed that the quality scores of the positive trials was similar to the negative ones, allowing us to conclude that they could be considered at the same level. No negative trial with a similar design can be opposed to each particular positive trial that is thus not conterbalanced. Moreover the trials not in favor of maintenance could be falsely negative by a lack of power, the publications mentioning no statistical consideration. There are thus a series of arguments in favor of maintenance chemotherapy for small-cell lung cancer, which require to be confirmed by randomised trials of adequate quality.

Antineoplastic Agents↗

PubMed1998

The routine use of atypical antipsychotic agents: maintenance treatment.

Placebo-controlled maintenance studies of conventional antipsychotic agents demonstrate a significant reduction in the risk of schizophrenic relapse in neuroleptic-treated patients. Neuroleptic discontinuation even in patients who remained in remission for as long as 5 years results in a relapse rate comparable to that seen for patients initially assigned to placebo. Yet, patients maintained on conventional neuroleptics are exposed to the risk of tardive dyskinesia (approximately 5% per year for patients with up to 10 years of neuroleptic exposure). Attempts have been made to reduce neuroleptic exposure. A lower maintenance dose was associated with higher relapse rates, as was intermittent, targeted therapy. Psychoeducational treatment studies reaffirmed that the major influence on the rate of rehospitalization was the dose of conventional maintenance medication. Although data are scarce for maintenance treatment with atypical antipsychotic drugs, findings suggest that atypical agents are at least as efficacious and may be better tolerated. Olanzapine has demonstrated efficacy in maintenance treatment as well as a reduced risk of tardive dyskinesia compared with haloperidol.

Antipsychotic Agents↗

PubMed2026

Efficacy and Safety of Anti-Obesity Medications for Weight Loss Maintenance in Adults With Overweight or Obesity: A Systematic Review and Meta-Analysis of Randomised Controlled Trials.

AIMS: This systematic review and meta-analysis aimed to evaluate the efficacy and safety of anti-obesity medications (AOMs) for long-term weight maintenance following initial weight loss in adults with overweight or obesity. METHODS: We searched PubMed, Embase, Web of Science and the Cochrane Library from inception to 31 October 2025. Eligible studies were randomised controlled trials (RCTs) comparing AOMs with placebo during the weight-maintenance phase in adults with overweight or obesity after initial weight loss achieved through lifestyle, dietary, surgical or pharmacological interventions. Outcomes included anthropometric indices, cardiometabolic measures, safety endpoints, quality of life and neuropsychiatric adverse events. Weighted mean differences (WMDs) and odds ratios (ORs), each with 95% confidence intervals (CIs), were pooled for continuous and categorical outcomes, respectively, using fixed-effect or random-effects models as appropriate. Risk of bias was assessed using the Cochrane RoB 2 tool, and certainty of evidence was evaluated using the GRADE framework. The protocol was registered with PROSPERO (CRD420261293040). RESULTS: A total of 12 RCTs comprising 4915 participants met the inclusion criteria. Compared with placebo, AOM therapy during the weight-maintenance phase was associated with prevention of weight regain and additional improvements in anthropometric and cardiometabolic outcomes. AOMs led to further reductions in body weight (BW, WMD: -8.68 kg, 95% CI: -13.25 to -4.11), waist circumference (WC, WMD: -7.16 cm, 95% CI: -10.34 to -3.98) and body mass index (BMI, WMD: -3.58 kg/m2, 95% CI: -5.69 to -1.46). Additional benefits were observed for triglycerides, total cholesterol, low-density lipoprotein cholesterol, systolic blood pressure and diastolic blood pressure. Gastrointestinal adverse events were more common with AOMs, whereas serious adverse events were not significantly increased. Neuropsychiatric adverse events were generally comparable between groups, and available quality-of-life measures favoured AOM treatment. CONCLUSIONS: AOM therapy during the weight-maintenance phase can help prevent weight regain, provide further reductions in body weight and improve cardiometabolic risk factors in adults with overweight or obesity. Gastrointestinal adverse events were more common with AOMs, whereas serious adverse events were not significantly increased. Further long-term trials are needed to clarify optimal treatment strategies and safety.

Humans↗

PubMed1992

Radiation therapy maintenance. A successful in-house program.

With the development of complex equipment technologies in the medical care industry and particularly in radiation therapy, the costs required to keep equipment in proper operating condition are substantial. An "in-house" radiation therapy maintenance program can provide significant savings in equipment maintenance costs as compared to the cost of maintenance contracts. Additionally, the skills of the personnel providing this maintenance program can be used for ancillary areas of the therapy department.

Costs and Cost Analysis↗

PubMed2007

Maintenance behaviour and long-lasting insecticide-treated nets (LLITNs) previously introduced into Bourapar district, Khammouane province, Lao PDR.

BACKGROUND: Long-lasting insecticide-treated nets (LLITNs) are expected to be an important advance in malaria control, but operational experience is still scarce. This study presents some operational findings concerning the introduction of Olyset LLITNs (Sumitomo Chemical Co., Ltd, Japan) in Laos. The study site, Bourapar district, a remote district at high risk of malaria, received Olyset nets during 1999-2000. After distribution of the nets the number of malaria cases in the district hospital decreased for a time, however it began to rise again a year after the intervention. To sustain the effect of the nets, net users were given instructions on maintenance and use. This study aimed to investigate the condition of Olyset nets and the maintenance behaviour of net users after 2-3 years of use, and to examine the associations between maintenance behaviour and the number of malaria episodes during the previous year. METHODS: Questionnaire interviews and inspections of nets were conducted at 240 households during February-March 2003. RESULTS: About 40% of the observed nets had holes/were torn, and the maintenance instructions had not been followed sufficiently. Households following the recommended washing frequency (38.2%) reported fewer malaria episodes during the past year, which demonstrates the importance of the recommended washing frequency in the effective use of the nets. CONCLUSIONS: Our study promotes the idea that, in addition to pursuing high coverage of LLITNs, more effort should be made to ensure that nets are kept in good condition in future LLITN programmes.

Adult↗

PubMed2003

Computer-aided planned maintenance system for medical equipments.

In this study, a software package is introduced, which has been developed to monitor and administer preventive maintenance activities for healthcare devices and system components in a hospital to provide uninterruptible operation in a computer-aided fashion. This software with its object-oriented and graphic user interface (GUI) nature aims to standardize preventive maintenance activities while providing overall optimization of material used in preventive maintenance activities; personnel administers the maintenance and time dedicated for the activities.

Decision Making, Computer-Assisted↗

PubMed2005

A system for the calculation and visualisation of radiation field for maintenance support in nuclear power plants.

A system has been developed to improve the efficiency of maintenance work while decreasing the radiation exposure of maintenance personnel in nuclear power plants. The input data for dose rate calculation are automatically generated by using computer-aided design data. Changes for the input data corresponding to the progress of maintenance work, such as installation of a radiation shield and removal of a component, are easily input interactively on a graphical user interface (GUI). A new method was proposed which searches the sets of source and detector points between which gamma-ray attenuation is changed by the component movement. The calculation is performed only for the changed sets, so that the change of the three-dimensional dose rate distribution is calculated rapidly according to the work progress. The dose rate distribution and the radiation exposure of maintenance personnel are displayed three-dimensionally in colour with plant components and pipes on the GUI.

Body Burden↗

PubMed1993

Alleviation of sleep maintenance insomnia with timed exposure to bright light.

OBJECTIVE: Half of the population over 65 suffers from chronic sleep disturbance. As a consequence, almost 40% of hypnotic medications are prescribed to people over age 60. Yet, hypnotics are often of little benefit in this population. As such, an effective non-drug alternative could prove important in the management of age-related sleep maintenance insomnia. The current study sought to evaluate the efficacy of bright light exposure in the treatment of sleep maintenance insomnia. DESIGN: Following baseline sleep and circadian rhythms assessment, subjects with sleep-maintenance insomnia were treated with timed exposure to either bright white light or dim red light for 12 consecutive days. Sleep and circadian rhythms recordings were subsequently obtained and measures of sleep quality were compared to assess efficacy of the treatments. SETTING: Baseline and post-treatment sleep and circadian rhythms assessments took place in the Laboratory of Human Chronobiology, Department of Psychiatry, Cornell University Medical College. The treatment phase of the study was conducted in participants' homes. PARTICIPANTS: Sixteen men and women between the ages of 62 and 81 years were studied. All subjects were free of hypnotic medication, and all had experienced sleep disturbance for at least 1 year prior to entering the study. RESULTS: Exposure to bright light resulted in substantial changes in sleep quality. Waking time within sleep was reduced by an hour, and sleep efficiency improved from 77.5% to 90%, without altering time spent in bed. Increased sleep time was in the form of Stage 2 sleep, REM sleep, and slow wave sleep. The effects were remarkably consistent across subjects. CONCLUSIONS: The findings demonstrate the effectiveness of timed exposure to bright light in the treatment of age-related sleep maintenance insomnia. With further refinement of treatment regimens, this non-drug intervention may prove useful in a large proportion of sleep disturbed elderly.

Age Factors↗

PubMed1979

Successful operation of a regional scheme for the maintenance of automatic analysers.

The main operational and financial aspects of the maintenance service provided by the West of Scotland Health Boards' Department of Clinical Physics and Bio-Engineering (DCPB) to the clinical chemistry laboratories in the region are described. The scheme, in operation since March 1976, covers all breakdown servicing and engineering preventive maintenance for Technicon Auto-Analyzer equipment valued at pounds 1 1/4 million in terms of direct replacement costs. The engineering team works closely with the laboratory staffs to ensure that the performance of the equipment is maintained to specification. The direct economies for the Health Boards through savings in maintenance contract charges total around pounds 60,000 per year. In addition, considerable sums have been saved by servicing, modifying, and constructing other instruments for the laboratories outwith the immediate remit of Technicon maintenance. Other economic and operational benefits which result from the scheme are commercially disinterested advice on equipment obsolescence and replacement, and redistribution between the laboratories of old but useful equipment to meet specific needs of the service in the region.

Autoanalysis↗

PubMed1997

A philosophical approach to treatment machine maintenance and breakdown.

Planned preventative maintenance (PPM), quality control (QC) checks and breakdown all contribute to the down-time of a radiotherapy treatment machine. Low levels of machine availability are unacceptable both clinically and financially. Clinical data demonstrate that, for many tumours, interruptions to treatment will result in reduced local control. Reductions to the gaps in treatment can be achieved by patient interchange between machines. Maintaining the maximum possible machine availability will reduce the potential for errors associated with the transfer of patients between machines, and reduce the cost of treatment. Practices for routine PPM and QC vary between hospitals. In this report, a rationale for breakdown and maintenance will be described. Based on the faults experienced on a Philips SL 75-5 and a Philips SL25 over a period of 3 years, the workload associated with routine maintenance and quality control are presented and the additional work associated with breakdown discussed. Faults have been categorized on a scale between catastrophe and maintainability. A demonstration of how this analysis can be used to assess the cost-benefits of proposed changes in working patterns by the extension or reduction of maintenance periods is provided. The results indicated that no gain would be made in changing from a 1-day to a 2-day per month PPM schedule.

Cost-Benefit Analysis↗

PubMed1982

Bilateral luteal maintenance in unilaterally pregnant pigs with infusions of embryonic extracts.

Thirty unilaterally pregnant gilts with bilateral corpora lutea received infusions three times daily into a surgically isolated, nonpregnant uterine horn from d 12 through d 19 after mating. The infusions consisted of either saline alone or embryonic extracts in saline which were either untreated, heat-treated or charcoal-absorbed. The extracts were from porcine embryos, embryonic membranes and fluids between d 16 and 25 of pregnancy. While only 20% of the gilts infused with saline alone and none of those infused with charcoal-absorbed embryonic extracts maintained pregnancy to d 19, 100 and 83% of the gilts infused with untreated and heal-treated embryonic extracts, respectively, were pregnant on d 19. Similar treatment effects were observed for the incidence of bilateral luteal maintenance. No gilts receiving infusions of either saline or charcoal-absorbed embryonic extracts exhibited bilateral luteal maintenance. However, 67% of the gilts infused with untreated embryonic extracts and 67% of those infused with heated extracts had bilateral luteal maintenance on d 19. Additionally, the weights and progesterone concentrations of corpora lutea adjacent to the infused uterine horns were not different (P less than .05) from those of the corpora lutea adjacent the to pregnant uterine horns in gilts with bilateral luteal maintenance.

Animals↗

PubMed2026

Crucial role of telomere maintenance-related genes in survival prediction and subtype identification in colorectal cancer.

BACKGROUND: Telomere maintenance-related genes (TMRGs) are implicated in Colorectal cancer (CRC) development, but their prognostic value and clinical relevance remain insufficiently explored. This study aims to develop a TMRG-based prognostic model and elucidate its clinical utility in CRC management. METHODS: The Cancer Genome Atlas database was utilized to download RNA-seq data from 638 CRC and 51 control samples. Differential expressed genes were screened and intersected with 2086 TMRGs, resulting in the identification of 976 TMRGs. Through univariate and multivariate Cox regression analysis, a prognostic model comprising three telomere maintenance-related biomarkers (PDE1B, TFAP2B, and HSPA1A) was developed and validated using an external dataset. By integrating the model risk score with clinical features, a nomogram was constructed to predict the survival outcomes of CRC patients. Additionally, an in-depth investigation of the immuno-infiltration, functional variation and drug sensitivity analysis were performed in two risk subgroups defined by the prognostic model. Finally, the functional significance of PDE1B in CRC cell lines was investigated through MTT assays, cell colony formation assays, transwell assays and flow cytometry. RESULTS: A total of 976 DE-TMRGs were enriched in telomere/DNA replication pathways. A three-gene signature (PDE1B, TFAP2B, and HSPA1A) stratified patients into high- and low-risk groups with divergent survival (AUC >0.60, validated externally). High-risk patients had advanced N/M stages, elevated M0/M2 macrophages, reduced CD4+ memory T cells, and upregulated immune checkpoints. Nomogram integrating risk score, age, and N/M stage accurately predicted 1-/3-/5-year survival. Low-risk patients showed greater 5-fluorouracil sensitivity. PDE1B expression was significantly reduced in CRC tissues and correlated with advanced stages. Functional assays confirmed PDE1B overexpression suppressed proliferation, migration, invasion, and induced apoptosis in CRC cells. CONCLUSION: This study identifies a moderately predictive telomere maintenance-related gene signature as an independent prognostic predictor in CRC. The risk stratification model effectively discriminates patients with distinct survival patterns, tumor microenvironments, and therapeutic responses, while the integrated nomogram offers additional reference information for survival analysis, albeit with only moderate predictive accuracy. These findings indicate telomere maintenance-related gene signature could serve as a preliminary auxiliary risk stratification tool for postoperative CRC patients, PDE1B may also serve as a potential epithelial tumor-suppressor target for future preclinical studies.

PDE1B↗

PubMed1999

Technology and the future of medical equipment maintenance.

Maintenance of medical equipment has been changing rapidly in the past few years. It is changing more rapidly in developed countries, but changes are also occurring in developing countries. Some of the changes may permit improved maintenance on the higher technology equipment in developing countries, since they do not require onsite expertise. Technology has had an increasing impact on the development of medical equipment with the increased use of microprocessors and computers. With miniaturization from space technology and electronic chip design, powerful microprocessors and computers have been built into medical equipment. The improvement in manufacturing technology has increased the quality of parts and therefore the medical equipment. This has resulted in increased mean time between failures and reduced maintenance needs. This has made equipment more reliable in remote areas and developing countries. The built-in computers and advances in software design have brought about self-diagnostics in medical equipment. The technicians now have a strong tool to be used in maintenance. One problem in this area is getting access to the self-diagnostics. Some manufacturers will not readily provide this access to the owner of the equipment. Advances in telecommunications in conjunction with self-diagnostics make available remote diagnosis and repair. Since components can no longer be repaired, a remote repair technician can instruct an operator or an on-site repairman on board replacement. In case of software problems, the remote repair technician may perform the repairs over the telephone. It is possible for the equipment to be monitored remotely by modern without interfering with the operation of the equipment. These changes in technology require the training of biomedical engineering technicians (BMETs) to change. They must have training in computers and telecommunications. Some of this training can be done with telecommunications and computers.

Equipment Failure↗

PubMed2003

Maintenance treatment is not necessary after Helicobacter pylori eradication and healing of bleeding peptic ulcer: a 5-year prospective, randomized, controlled study.

BACKGROUND: It is well accepted that in patients with uncomplicated peptic ulcers, Helicobacter pylori eradication therapy does not need to be followed by further antisecretory treatment. However, it is uncertain whether patients with bleeding peptic ulcers should receive maintenance antiulcer therapy after successful H pylori eradication and ulcer healing. The aim of this 5-year, prospective, randomized, controlled study was to investigate the role of long-term maintenance therapy after successful H pylori eradication and healing of bleeding ulcers. METHODS: A total of 82 consecutive patients with H pylori-associated bleeding peptic ulcers were enrolled in the study. After successful H pylori eradication with the 1-week proton pump inhibitor-based triple therapy and an additional 3-week treatment with 20 mg of omeprazole daily for ulcer healing, the patients were assigned to one of four 16-week maintenance treatment groups as follows: group A received 15 mL of an antacid suspension 4 times daily; group B received 300 mg of colloidal bismuth subcitrate 4 times daily; group C received 20 mg of famotidine twice daily; and group D, the control group, received placebo twice daily. Follow-up included an urea breath test labeled with carbon 13, biopsy-based tests, and repeated endoscopic examination. RESULTS: An analysis of variance revealed no difference in mean age and mean follow-up time among the groups. During a mean follow-up of 56 months, there was no peptic ulcer recurrence among the 3 treatment groups, and all of the patients remained free of H pylori infection during the study period. CONCLUSIONS: In patients with bleeding peptic ulcers, antiulcer maintenance treatment was not necessary to prevent ulcer recurrence after successful H pylori eradication and ulcer healing. In addition, the 1-week proton pump inhibitor-based triple therapy had the efficacy to ensure long-term eradication of H pylori in a region of high prevalence.

Adult↗

PubMed1990

Three-year outcomes for maintenance therapies in recurrent depression.

We conducted a randomized 3-year maintenance trial in 128 patients with recurrent depression who had responded to combined short-term and continuation treatment with imipramine hydrochloride and interpersonal psychotherapy. A five-cell design was used to determine whether a maintenance form of interpersonal psychotherapy alone or in combination with medication could play a significant role in the prevention of recurrence. A second question was whether maintaining antidepressant medication at the dosage used to treat the acute episode rather than decreasing to a "maintenance" dosage would provide prophylaxis superior to that observed in earlier trials in which a maintenance dosage strategy was employed. Survival analysis demonstrated a highly significant prophylactic effect for active imipramine hydrochloride maintained at an average dose of 200 mg and a modest prophylactic effect for monthly interpersonal psychotherapy. We conclude that active imipramine hydrochloride maintained at an average dose of 200 mg is an effective means of preventing recurrence and that monthly interpersonal psychotherapy serves to lengthen the time between episodes in patients not receiving active medication.

Adult↗

PubMed2000

A randomized, placebo-controlled 12-month trial of divalproex and lithium in treatment of outpatients with bipolar I disorder. Divalproex Maintenance Study Group.

BACKGROUND: Long-term outcomes are often poor in patients with bipolar disorder despite treatment; more effective treatments are needed to reduce recurrences and morbidity. This study compared the efficacy of divalproex, lithium, and placebo as prophylactic therapy. METHODS: A randomized, double-blind, parallel-group multicenter study of treatment outcomes was conducted over a 52-week maintenance period. Patients who met the recovery criteria within 3 months of the onset of an index manic episode (n = 372) were randomized to maintenance treatment with divalproex, lithium, or placebo in a 2:1:1 ratio. Psychotropic medications were discontinued before randomization, except for open-label divalproex or lithium, which were gradually tapered over the first 2 weeks of maintenance treatment. The primary outcome measure was time to recurrence of any mood episode. Secondary measures were time to a manic episode, time to a depressive episode, average change from baseline in Schedule for Affective Disorders and Schizophrenia-Change Version subscale scores for depression and mania, and Global Assessment of Function scores. RESULTS: The divalproex group did not differ significantly from the placebo group in time to any mood episode. Divalproex was superior to placebo in terms of lower rates of discontinuation for either a recurrent mood episode or depressive episode. Divalproex was superior to lithium in longer duration of successful prophylaxis in the study and less deterioration in depressive symptoms and Global Assessment Scale scores. CONCLUSIONS: The treatments did not differ significantly on time to recurrence of any mood episode during maintenance therapy. Patients treated with divalproex had better outcomes than those treated with placebo or lithium on several secondary outcome measures.

Ambulatory Care↗

PubMed2006

Effects of lower-cost incentives on stimulant abstinence in methadone maintenance treatment: a National Drug Abuse Treatment Clinical Trials Network study.

BACKGROUND: Contingency management interventions that provide tangible incentives based on objective indicators of drug abstinence have improved treatment outcomes of substance abusers, but have not been widely implemented in community drug abuse treatment settings. OBJECTIVE: To compare outcomes achieved when a lower-cost prize-based contingency management treatment is added to usual care in community methadone hydrochloride maintenance treatment settings. DESIGN: Random assignment to usual care with (n = 198) or without (n = 190) abstinence incentives during a 12-week trial. SETTING: Six community-based methadone maintenance drug abuse treatment clinics in locations across the United States. PARTICIPANTS: Three hundred eighty-eight stimulant-abusing patients enrolled in methadone maintenance programs for at least 1 month and no more than 3 years. INTERVENTION: Participants submitting stimulant- and alcohol-negative samples earned draws for a chance to win prizes; the number of draws earned increased with continuous abstinence time. MAIN OUTCOME MEASURES: Total number of stimulant- and alcohol-negative samples provided, percentage of stimulant- and alcohol-negative samples provided, longest duration of abstinence, retention, and counseling attendance. RESULTS: Submission of stimulant- and alcohol-negative samples was twice as likely for incentive as for usual care group participants (odds ratio, 1.98; 95% confidence interval, 1.42-2.77). Achieving 4 or more, 8 or more, and 12 weeks of continuous abstinence was approximately 3, 9, and 11 times more likely, respectively, for incentive vs usual care participants. Groups did not differ on study retention or counseling attendance. The average cost of prizes was 120 dollars per participant. CONCLUSION: An abstinence incentive approach that paid 120 dollars in prizes per participant effectively increased stimulant abstinence in community-based methadone maintenance treatment clinics.

Adult↗

PubMed2000

Mechanisms of virologic failure in previously untreated HIV-infected patients from a trial of induction-maintenance therapy. Trilège (Agence Nationale de Recherches sur le SIDA 072) Study Team).

CONTEXT: In the Trilège trial, following induction with a zidovudine, lamivudine, and indinavir regimen, human immunodeficiency virus (HIV) replication was less suppressed by 2-drug maintenance therapy than by triple-drug therapy. OBJECTIVE: To identify mechanisms of virologic failure in the 3 arms of the Trilège trial. DESIGN: Case-control study conducted from February to October 1998. SETTING: Three urban hospitals in Paris, France. PATIENTS: Fifty-eight case patients with virologic failure (HIV RNA rebound to >500 copies/mL in 2 consecutive samples) randomized to 3 therapy groups: triple drug (zidovudine, lamivudine, and indinavir), 8; zidovudine-lamivudine, 29; and zidovudine-indinavir, 21; the case patients were randomly matched with 58 control patients with sustained viral suppression. MAIN OUTCOME MEASURES: At virologic failure (S1 sample) and 6 weeks later (S2 sample), assessment of protease and reverse transcriptase gene mutations, plasma indinavir level, and degree of viral load rebound; pill count during induction and maintenance periods. RESULTS: Only 1 primary resistance mutation, M184V, was detected in S1 plasma samples from 4 of 6 patients in the triple-drug and in all 22 in the zidovudine-lamivudine therapy groups and in S2 plasma samples from 3 of 6 in the triple-drug and 20 of 21 in the zidovudine-lamivudine groups. Of controls, M184V was detected in 11 of 13 S1 plasma samples and in 10 of 11 S2 plasma samples. Indinavir levels were undetectable in all S1 samples but 2 in 7 triple-drug cases tested and in the expected range in 11 of 18 S1 and 5 of 12 S2 zidovudine-indinavir case plasma samples tested. Maintenance adherence rates were lower for cases vs controls for zidovudine (P = .05) and indinavir (P = .05). Low indinavir levels, lower adherence rates for zidovudine (P = .04) and lamivudine (P = .03), and rebound to near-baseline values suggested adherence as cause of early failure for 4 of 8 triple-drug cases. In the zidovudine-lamivudine arm, for which case and control adherence rates did not differ significantly (P = .96), most failures occurred late with low rebound, suggesting suboptimal drug potency. In the zidovudine-indinavir arm, virologic failures may be related to both mechanisms. CONCLUSIONS: During the maintenance phase early and late virologic failures appeared to be related more to problems of adherence and antiretroviral treatment potency, respectively, than to selection of resistant mutant viruses.

Anti-HIV Agents↗