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Rationale: To determine the dosage requirements and pharmacokinetics of atevirdine, a non-nucleoside reverse transcriptase inhibitor and its N-dealkylated metabolite (N-ATV) during phase I studies in patients receiving atevirdine alone or in combination with zidovudine., Design: Two open label, phase I studies conducted by the adult AIDS Clinical Trials Group (ACTG) in which atevirdine was administered every 8 h with weekly dosage adjustments to attain targeted trough plasma atevirdine concentrations., Setting: Five Adult AIDS Clinical Trials Units., Patients: Fifty patients (ACTG 199; n = 20 and ACTG 187; n = 30) with HIV-1 infection and < or =500 CD4+ lymphocytes/mm3., Intervention: ACTG 199; 12 weeks of therapy with atevirdine (dose-adjusted to achieve plasma trough atevirdine concentrations of 5-10 microM) and zidovudine (200 mg every 8 h). ACTG 187: 12 weeks of atevirdine monotherapy with atevirdine doses adjusted to achieve escalating, targeted trough plasma concentration ranges (5-13, 14-22, and 23-31 microM)., Measurements: ACTG 199: atevirdine, N-ATV and zidovudine trough determinations weekly (all patients) and intensive pharmacokinetics (selected patients) prior to and at 6 and 12 weeks during combination therapy. ACTG 187: atevirdine and N-ATV trough concentrations over a 12 week period. Intensive pharmacokinetic studies were conducted prior to and at 4 and/or 8 weeks during atevirdine monotherapy in female patients., Results: Atevirdine plasma concentrations demonstrated considerable interpatient variability which was minimized by the adjustment of maintenance doses (range: 600-3900 mg/day) to achieve the desired trough concentrations. In ACTG 187, the mean number of weeks to attain the target value, and the percentage of patients who attained the target, was group I (5-11 microM): 2.7+/-2.4 weeks (92%); group II (12-21 microM): 2.6+/-1.8 (64%); and group III (22-31 microM): 7.0+/-5.6 weeks (27%). In ACTG 199 it was 3.2+/-5.2 weeks (95%) to achieve a 5-10 microM trough. Atevirdine demonstrated a mono- or bi-exponential decline among most of the patients studied after the first dose. During multiple-dosing a number of patterns of atevirdine disposition were observed including; rapid absorption with Cmax at 0.5-1 h, delayed absorption with Cmax at 3-4 h; minimal Cmax to Cmin fluctuation and Cmax to Cmin ratios of > 4. N-ATV (an inactive metabolite) patterns were characterized on day one by rapid appearance of the metabolite which peaked at 2-3 h after the dose and declined in a mono- or bi-exponential manner. At steady-state N-ATV patterns demonstrated minimal Cmax to Cmin fluctuations with some of the patients having more stable plasma N-ATV concentrations, while others had greater fluctuations week to week., Conclusions: Considerable interpatient variability was noted in the pharmacokinetics of atevirdine. The variation in drug disposition was reflected in the range of daily doses required to attain the targeted trough concentrations. Atevirdine metabolism did not appear to reach saturation during chronic dosing in many of our patients, as reflected by the pattern of N-ATV/ATV ratios in plasma and saturation was not an explanation for the variation in dosing requirements. No apparent differences were noted between males and females, and atevirdine did not appear to influence zidovudine disposition.

Objective: Highly active antiretroviral therapy (HAART) can produce marked increases in peripheral blood CD4+ T cells and decreases in HIV plasma RNA copy numbers. However, it is not clear whether these absolute changes will be accompanied by a recovery in the known naive CD4+ T cell depletion or a decrease in the marked CD8+ T cell activation., Design: Twenty-nine patients were enrolled in studies of either nucleoside therapy alone or nucleoside therapy combined with a protease inhibitor (zidovudine + lamivudine + indinavir). One hundred and ninety-one examinations were carried out at three baseline time points and during 40 weeks of follow-up to evaluate the effect of HAART on CD4+ memory/naive phenotype and CD8+ T cell activation., Methods: CD4+ and CD8+ T cell number, CD62L/CD45RA expression on CD4+ T cells and CD38 expression on CD8+ T cells were measured by three-color flow cytometry., Results: Most protease inhibitor treated patients had a significant rise in CD4+ numbers. The marked rise in the CD4+ T cells seen in individuals in this study was not accompanied over a 40-week period by a change in the abnormally low CD4+ naive compartment, and thus was almost completely of memory phenotype. The CD38 expression on CD8+ cells fell during treatment, and decreased to a greater degree than the comparable rise in CD4+ T cell counts. This decrease continued in many patients after the CD4+ T cell rise or viral load decline had plateaued., Conclusion: HAART results in changes in activation to a greater extent than absolute changes in CD4+ T cell numbers, but is not accompanied by an increase in naive CD4+ T cells. Measurements of CD4+ T cell numbers alone may not allow appropriate interpretation of immune activation or immune competence in patients receiving those drugs.

Forty-nine subjects were enrolled in a study comparing two dosages of parenterally administered interferon (IFN)-beta in combination with cryotherapy for the treatment of anogenital warts. Subjects were randomized to receive subcutaneous injections of either 2 x 10(6) or 4 x 10(6) IU/m2 of IFN-beta (Biogen) three times a week for a total of 6 weeks. Cryotherapy was administered concomitantly by aerosolization of liquid nitrogen at 10-day intervals. Systemic side- effects were modest in intensity and included fever, chills, myalgia, and headaches (flu-like symptoms). During the first 2 weeks of therapy, they were more common in the high dose group than in the low dose group (P = 0.02). Using survival analysis, there was no significant difference between the two groups in rates of resolution of warts present at baseline (P = 0.62). However, the rate of new lesion formation during the study was significantly lower in the high dose group (P = 0.04).

Thirty HIV isolates, obtained from 15 patients before and after receiving single drug therapy with didanosine (ddI), were examined for sensitivity to ddI and zidovudine (ZDV) using a peripheral blood mononuclear leukocyte (PBML)-based assay. Fourteen of the patients had ARC, one had AIDS and 12 had received previous therapy with ZDV. After a median of 1 year of ddI therapy, isolates were significantly less sensitive to ddI than were isolates obtained prior to therapy (P = 0.03). A decrease in ddI sensitivity was observed in ten of the 15 isolate pairs. In contrast to ddI susceptibilities, sensitivity to ZDV increased over the same period of time (P = 0.03). Additional isolates were obtained from four patients who received ddI monotherapy for 2 years. Three of these isolates demonstrated no change in ddI sensitivity compared to baseline. No correlation could be made in this study between development of decreased ddI sensitivity and serum p24 levels, CD4 counts, or clinical outcome. Decreased ddI sensitivity occurs frequently among HIV isolates obtained from long-term recipients of ddI. This decreased sensitivity is modest in degree and is of unknown clinical significance.

HPV infection of the genital tract is common and anogenital warts or condyloma acuminatum is increasing rapidly in incidence. In addition, certain HPV types are closely associated with genital tract malignancies. Although recent advances in molecular biology have led to an increased understanding of the organization and functions of the papillomavirus genome, the pathogenesis of HPV infections and host responses to these diseases remain poorly understood. Treatment of anogenital warts is difficult and no completely satisfactory treatment modality is currently available. Comparatively few therapeutic modalities have been thoroughly evaluated, although recent studies of intralesionally and parenterally administered interferons have demonstrated beneficial effects of interferon compared to placebo. Additional studies of treatment for condyloma acuminatum are needed and should include the use of biologic response modifiers such as interferons, as well as antiviral drugs, with or without conventional methods of local therapy.

Peripheral blood mononuclear leukocytes (PBML) from 21 human donors seropositive for herpes simplex virus (HSV) type 1, and from seven seronegative donors were employed to produce interferon (IFN) in response to stimulation by HSV and phytohemagglutinin (PHA). Cryopreserved PBML produced titers of IFN, including immunespecific IFN, that were not significantly different from titers produced by freshly prepared PBML. In addition, cryopreserved PBML stored under conditions designed to simulate inter-institutional exchange of specimens produced quantities of IFN that did not vary significantly from quantities of IFN produced by cryopreserved cells that were stored under conventional conditions. Production of immunespecific IFN by cryopreserved cells represents an example of a measurement of cell-mediated immunity that is analogous in reliability and flexibility to currently available measurements of humoral immune responses.

This multi-center trial compared two doses of parenterally administered interferon alpha-n1 (Wellferon) in men and women with recurrent/resistant genital warts. Patients received either 1 or 3 MU/m2 daily for 14 days, then 3 times weekly for 4 weeks; non-responders could receive an additional four weeks of treatment. A total of 107 patients were enrolled, and 102 were evaluable after six weeks of study. The principal dose comparison was in 57 women assigned alternately to the two doses. Median lesion measurements were reduced significantly from baseline at weeks 2, 4 and 6 in both groups. Statistical analysis showed no difference in response to 1 versus 3 MU/m2. The overall complete response (CR) plus partial response (PR) rate at week 6 was 69% for the two doses. Two additional groups of 21 women and 24 men were treated at the higher dose with CR plus PR rates of 75 and 50%, respectively. Week 10 disease evaluations for all groups showed 19 of 77 patients to be completely cleared. Of these 19, only one had recurrent disease at the end of the 6-month study period. Analysis of the incidence of symptomatic side effects showed a significantly higher frequency among women treated with 3 MU/m2 than among women treated with 1 MU/m2. Five dose reductions and two withdrawals for toxicity occurred, all in the high dose group. This study demonstrates that parenterally administered Wellferon produces clearance of resistant genital warts in many patients, and that rates of clearance do not appear to vary between groups receiving moderate or low dose therapy.

Zidovudine (formerly azidothymidine, AZT) is used to treat certain patients infected with the human immunodeficiency virus (HIV). However, the clinical use of zidovudine (ZDV) in hemophilia patients may be complicated by the high incidence of chronic hepatitis in this patient population. To examine the pharmacokinetics of ZDV eight asymptomatic HIV-infected hemophilia patients received a single oral dose (300 mg). ZDV and its glucuronide metabolite (GZDV) were measured in serum by HPLC. ZDV was rapidly absorbed with a wide range of peak serum concentrations (2052 +/- 970 ng/ml) at 0.5 h. Peak GZDV serum concentrations were 4751 +/- 2269 ng/ml at 1 h. Both ZDV and GZDV declined in a biexponential manner over 4 h. After 4 h, the ZDV serum concentration decay in three patients continued a log-linear decline, while five patients demonstrated a tri-exponential curve which had a mean terminal elimination half-life of 4.8 +/- 2.8 h. No relationship between ZDV or GZDV kinetics and the degree of hepatic enzyme elevation was observed. Although a therapeutic window for ZDV has yet to be described, the wide range of serum concentrations that result from a standard dose suggests that clinical monitoring of ZDV levels may be of value in certain patients. In addition, the prolonged elimination half-life of ZDV in the present study may provide a rationale for less frequent dosing in certain patients.