[The reduction of mother-child transmission of HIV infection in developing countries: potential intervention strategies, obstacles to implementation and perspectives. The Reduction of Mother-Child Transmission of HIV Infection in Africa Group]

Mother to child transmission (MCT) of Human Immunodeficiency Virus (HIV) is the main cause of the spread of the HIV epidemic in the pediatric population. It is estimated that to date, three million children worldwide have been infected by HIV. The epidemic burden in developing countries is dramatic. Ninety-five percent of the world's HIV-infected women are living in developing countries. In industrialized countries, antiretroviral treatment of pregnant women and newborns with azidothymidine (AZT, ACTG 076 regimen) and discouraging breast feeding by HIV-infected mothers are effectively reducing MCT of HIV. However, there are three major obstacles to the systematic application of these strategies in developing countries: (a) difficulties in implementing the complex AZT administration and its corollary the avoidance of breast feeding; (b) the complexity of the logistics of the ACTG 076 regimen; (c) cost. Indeed, in developing countries the socioeconomic situation of the populations are precarious and health structures and services are underdeveloped. In addition, the anxiety and the reluctance of general population in the face of the HIV problem and the high prevalence of maternal anemia reduce the acceptability and safety of AZT treatment for pregnant women in developing regions. Only interventions that are applicable, acceptable, safe, affordable, of low cost and integrated into health system will be able to reduce HIV MCT. We now know that MCT occurs mostly during the perinatal period and the maternal viral load in blood, in cervical secretions and in breast milk appears to be the main determinant of transmission. Maternal vitamin A deficiency may also favor MCT of HIV. It is however possible that this association is confounded by the relationship between advanced maternal HIV disease (a known risk factor for transmission) and vitamin A deficiency. In spite of these uncertainties concerning determinants of MCT of HIV, several interventions have been designed. The first involves treating the mother with antiretroviral drugs for the perinatal period. The second is vaginal disinfection by application of virucidal antiseptics during the perinatal period. The third is to give vitamin A supplements to pregnant women and children. Finally, passive immunotherapy with anti-HIV antibodies applied to pregnant women and/or new born, may be beneficial. The feasibility, safety and efficacy of these potential interventions have not yet been demonstrated in developing countries. In view of the dramatic spread of HIV infection in these countries, the evaluation of these interventions is of utmost priority. These trials are necessary because of the public health emergency but should be performed in strict respect of human rights and medical ethics.

HIV-1 protease inhibitors. A review for clinicians

OBJECTIVE

The clinical care of people infected with human immunodeficiency virus (HIV) has been substantially affected by the introduction of HIV-specific protease inhibitors (PIs). The 4 PIs available are saquinavir mesylate, ritonavir, indinavir sulfate, and nelfinavir mesylate. Comparison studies have not been reported; therefore, an assessment of the available data to aid clinicians and patients in choosing appropriate treatment will be presented.

DATA SOURCES

A systematic review of peer-reviewed publications, abstracts from national and international conferences, and product registration information through September 1996.

STUDY SELECTION AND DATA EXTRACTION

Criteria used to select studies include their relevance to PIs, having been published in the English language, and pertinence for clinicians. Data quality and validity included the venue of the publication and relevance to clinical care.

DATA SYNTHESIS

Oral adminstration of ritonavir, indinavir, or nelfinavir generates sustainable drug serum levels to effectively inhibit the protease enzyme; however, saquinavir may not generate sustained levels necessary to inhibit the protease enzyme. Patients treated with ritonavir, indinavir, or nelfinavir experience similar reductions in viral load and increases in CD4+ lymphocytes; smaller effects occur among those treated with saquinavir. Two randomized placebo-controlled studies conducted among patients with severe immune system suppression and substantial zidovudine treatment experience demonstrated reduced HIV disease progression and reduced mortality with PI treatment. Genotypic resistance to PIs occurs; the clinical relevance of resistance is unclear. The costs of these agents including required monitoring impose new and substantial costs.

CONCLUSIONS

The PIs have emerged as critical drugs for people with HIV infection. Optimal use involves combination with reverse transcriptase inhibitors. Resistance develops to each agent, and cross-resistance is likely. These agents must be used at full doses with attention to ensuring patient compliance. The expense of these agents may be offset by forestalling disease progression and death and returning people to productive life. Selecting the initial PI must be individualized, and factors to consider include proven activity, possible toxicities, dosing regimens, drug interactions, and costs.

The eleventh international conference on AIDS: cautious celebration in Vancouver

For the first time in the short but turbulent history of the International Conference on AIDS (acquired immune deficiency syndrome), participants found themselves in the midst of a sea change in the treatment of human immunodeficiency virus (HIV) disease. Scientists, health policy experts, politicians, and AIDS activists alike shared the anticipation. Report after report heralded improved outcomes in patients receiving combination therapy rather than monotherapy with reverse transcriptase inhibitors, particularly when investigators combined these agents with newly available protease inhibitors. The drug combinations dramatically reduced viral load in plasma, in some cases to undetectable levels, resulting in sharp rebounds in immune function. Even more encouraging is the pipeline for new and possibly more effective strategies. The cost of the new therapy for HIV disease, however, will limit the benefit to no more than 10% of the world's population infected with the virus.

How business is dealing with the AIDS epidemic

Employers geared up for astronomical HIV-related claims, but the avalanche never came. As new treatments improve prognoses and increase costs, the innovations of forward-thinking companies suggest useful strategies.

A utility assessment of oral and intravenous ganciclovir for the maintenance treatment of AIDS-related cytomegalovirus retinitis

The purpose of this study was to determine the magnitude of the difference in patient preference/utility for intravenous (i.v.) ganciclovir compared with oral ganciclovir for maintenance treatment of cytomegalovirus (CMV) retinitis. We used a cross-sectional, interviewer-administered time trade-off (TTO) exercise with hypothetical health state descriptions, based upon data from clinical trials and the published literature. The study was conducted in a private clinic in Sydney Australia, specialising in the care of people with HIV. A total of 80 individuals with HIV infection who had not developed AIDS were administered the TTO instrument. The main outcome measure was the difference between each respondent's utility score for oral and i.v. ganciclovir maintenance therapy. When the 80 HIV-positive patients were presented with information on drug efficacy, adverse effects and mode of administration, 60 (75%) preferred oral ganciclovir, 4 patients preferred i.v. ganciclovir, and 16 were indifferent. The median utilities were 0.837 (oral ganciclovir) and 0.475 (i.v. ganciclovir). The difference in rankings was statistically significant by Wilcoxon's signed-ranks test (Z = -6.69, p < 0.00005). The median utility scores suggest that, all other things being equal, individuals with HIV infection would prefer an oral formulation of ganciclovir to i.v. administration in the event of CMV retinitis infection.