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Biomedical subjects

M A Fischl

Publications and source records attributed to M A Fischl.

At least 37 records · Page 2Linked to original sources

Antiretroviral therapy for HIV infection in 1997. Updated recommendations of the International AIDS Society-USA panel.

OBJECTIVE: To provide current recommendations for antiretroviral therapy for human immunodeficiency virus (HIV) disease. PARTICIPANTS: The original International AIDS Society-USA 13-member panel representing international expertise in antiretroviral research and care of patients with HIV infection. EVIDENCE: The following were considered: Newly available clinical and basic science study results, including phase 3 controlled trials; clinical, virological, and immunologic end-point data; interim analyses of studies presented at national and international research conferences; studies of HIV pathophysiology; and expert opinions of panel members. Recommendations were limited to the drugs available in mid 1997. PROCESS: The full panel met on a regular basis (July 1996, September 1996, November 1996, January 1997, and April 1997) since the publication of its initial recommendations in mid 1996 to review new research reports and interim results. The panel discussed whether and how new information changed its initial recommendations. The recommendations contained herein were determined by group consensus. CONCLUSIONS: New data have provided a stronger rationale for earlier initiation of more aggressive therapy than previously recommended and reinforce the importance of careful selection of initial drug regimen for each patient for optimal long-term clinical benefit and adherence. The plasma viral load is a crucial element of clinical management for assessing prognosis and the effectiveness of therapy, and such testing must be done properly. Treatment failure is most readily indicated by a rising plasma HIV RNA level and should be confirmed prior to a change of treatment. Therapeutic approaches must be updated as new data, particularly on the long-term clinical effect of aggressive antiretroviral treatment, continue to emerge.

Anti-HIV Agents↗

Monitoring plasma HIV-1 RNA levels in addition to CD4+ lymphocyte count improves assessment of antiretroviral therapeutic response. ACTG 241 Protocol Virology Substudy Team.

BACKGROUND: CD4+ lymphocyte counts and plasma HIV-1 RNA levels predict progression of HIV-related disease, but the relative importance of these and other virological factors in defining response to antiretroviral therapy is not yet clear. OBJECTIVE: To determine the short-term variability of plasma HIV-1 RNA level during stable therapy; the relative importance of pretreatment values and early changes in CD4+ count, HIV-1 RNA levels, and infectious HIV-1 titers in mononuclear cells of peripheral blood and pretreatment syncytium-inducing phenotype of an HIV-1 isolate for prediction of disease progression and decline in CD4+ counts during therapy. DESIGN: Data were collected prospectively in a randomized, clinical trial comparing two combination regimens (ACTG [AIDS Clinical Trials Group] Protocol 241) and pooled across treatments. SETTING: 8 AIDS Clinical Trials Units. PATIENTS: 198 adults with HIV-1 infection and no more than 350 CD4+ lymphocytes/mm3 who had received at least 6 months of nucleoside therapy. INTERVENTIONS: All patients received zidovudine and didanosine; 100 received nevirapine and 98 received placebo. MEASUREMENTS: CD4+ lymphocyte counts, plasma HIV-1 RNA levels, and infectious HIV-1 titers in cells were measured before and 8 and 48 weeks after study treatment. Assay for the syncytium-inducing viral phenotype was done at baseline. Progression was defined as occurrence of opportunistic infection, malignancy, or death during the 48 weeks after treatment began. RESULTS: The difference between two measurements of HIV-1 RNA levels at baseline was within +/-0.39 log10 copies/mL (2.5-fold) for 90% of 167 patients receiving stable therapy. In a multivariate model, risk for disease progression was reduced by 56% (95% CI, 8% to 79% [P = 0.028]) for every 10-fold lower HIV-1 RNA level at baseline, by 52% (CI, 6% increase to 79% reduction [P = 0.071]) for every 10-fold reduction in HIV-1 RNA level at 8 weeks after treatment initiation, and by 67% (CI, 42% to 81% [P < 0.001]) for every 2-fold higher CD4+ count at baseline. These risk factors and syncytium-inducing viral phenotype at baseline, but not infectious HIV-1 titers in circulating cells, were associated with change in CD4+ counts over 48 weeks. CONCLUSIONS: For an individual patient, a change in plasma HIV-1 RNA level of 2.5-fold or more probably indicates a true biological change. Monitoring HIV-1 RNA levels and CD4+ lymphocytes before a change in antiretroviral treatment and monitoring HIV-1 RNA levels shortly thereafter improves prediction of disease progression and decline in CD4+ counts for 1 year compared with monitoring CD4+ counts of HIV-1 RNA levels alone. Additional monitoring of infectious HIV-1 titers in mononuclear cells of peripheral blood is not useful.

Acquired Immunodeficiency Syndrome↗

Phase I/II study of the toxicity, pharmacokinetics, and activity of the HIV protease inhibitor SC-52151.

SC-52151, an HIV-1 protease inhibitor, was developed as an ethanol-based elixir and subsequently as a self-emulsifying drug delivery system (SEDDS) to improve bioavailability. To evaluate formulation and treatment regimen effects, we conducted a four-arm, phase I/II study using the highest previously tested daily dose, 2250 mg. Forty-nine patients received the elixir or SEDDS at a dosage of 750 mg three times daily or 1125 mg twice daily for 14 days. One patient developed hypertriglyceridemia, and one had fever and dyspnea. The SEDDS formulation compared with the elixir resulted in a larger area under the concentration-time curve (AUC, p < 0.001), peak (Cmax, p = 0.041) and trough (Cmin, p = 0.025). Twice-daily administration compared with administration three times daily produced a higher cumulative AUC (p = 0.008). Both SEDDS regimens produced mean plasma concentrations above the 90% inhibitory concentration (IC90) for HIV. A mean decline of 0.03 log10 RNA copies (SEDDS) and an increase of 0.15 log10 (elixir) were observed. Although SC-52151 was well tolerated and the SEDDS formulation resulted in plasma concentrations above the IC90 for viral replication, no antiviral activity was produced.

Adult↗

Single-dose pharmacokinetics of delavirdine mesylate and didanosine in patients with human immunodeficiency virus infection.

Delavirdine is a nonnucleoside reverse transcriptase inhibitor with in vitro activity against human immunodeficiency virus type 1 (HIV-1) that is currently being evaluated in combination regimens with various nucleoside analogs, including didanosine. Due to the pH-dependent solubility of delavirdine, the buffering agents in didanosine formulations may reduce delavirdine absorption. To evaluate the potential interaction between these agents, 12 HIV-infected patients (mean [+/- standard deviation] CD4+ cell count, 304 +/- 213/mm3) were enrolled in a three-way crossover single-dose study. Didanosine (125 to 200 mg given as buffered tablets) and delavirdine mesylate (400 mg) pharmacokinetics were evaluated when each drug was given alone (treatments A and B, respectively), when the two drugs were given concurrently (treatment C), and when didanosine was given 1 h after delavirdine (treatment D). Delavirdine exposure was reduced by concurrent administration of didanosine. The maximum drug concentration in serum (Cmax) was reduced from 7.22 +/- 4.0 to 3.51 +/- 1.9 microM, and the area under the concentration-time curve from 0 h to infinity (AUC0-->infinity) was reduced from 22.5 +/- 14 to 14 +/- 5.7 microM.h. The extent of N-dealkylation, as indicated by the ratio of the N-dealkylated delavirdine AUC0-->infinity to the delavirdine AUC0-->infinity, was unchanged across study treatments (P = 0.708). Reductions in didanosine exposure were observed during concurrent administration with delavirdine with a Cmax reduction from 4.65 +/- 2.0 to 3.22 +/- 0.59 microM and an AUC0-->infinity reduction from 7.93 +/- 3.9 to 6.54 +/- 2.3 microM.h. Thus, concurrent administration of delavirdine and didanosine may reduce the AUC0-->infinity of both drugs, although the clinical significance of this reduction is unknown. Administration of delavirdine 1 h before didanosine avoided the interaction. Due to the single-dose nature of this study, these findings require further evaluation at steady state.

Acquired Immunodeficiency Syndrome↗

The Tat and C2-V3 envelope genes in the molecular epidemiology of human immunodeficiency virus-1.

In this study HIV-1 proviral DNA sequences derived from 201 clones of the C2-V3 env region and the first exon of tat were obtained from six HIV-1-infected heterosexual couples. These molecular data were used to confirm the epidemiological relationships. The ability of the molecular data to draw such conclusions was also tested. A bootstrap parsimony analysis of the C2-V3 sequences showed one couple failed to cluster and only two couples clustered in more than 70% of the replicates. The rapid diversification of the C2-V3 region and the length of time that elapsed since the infection event may have limited the certainty of the conclusions that can be reached to infer epidemiological relatedness from this region. Using data from the tat region, all couples clustered, four of them in more than 80% of bootstrap replicates. A single clone from the tat region did not cluster with others from that patient or with those from that patient's partner, indicating that multiple clones are necessary to firmly establish phylogenetic linkage. Nevertheless, the tat region was much more useful in establishing epidemiological relationships among this group than the commonly used C2-V3.

Amino Acid Sequence↗

Antiretroviral therapy for HIV infection in 1996. Recommendations of an international panel. International AIDS Society-USA.

OBJECTIVE: To provide clinical recommendations for antiretroviral therapy for human immunodeficiency virus (HIV) disease with currently (mid 1996) available drugs. When to start therapy, what to start with, when to change, and what to change to were addressed. PARTICIPANTS: A 13-member panel representing international expertise in antiretroviral research and HIV patient care was selected by the international AIDS Society-USA. EVIDENCE: Available clinical and basic science data, including phase 3 controlled trials, clinical endpoint data, virologic and immunologic endpoint data, interim analyses, studies of HIV pathophysiology, and expert opinions of panel members were considered. Recommendations were limited to drugs available in mid 1996. PROCESS: For each question posed, 1 or more member(s) reviewed and presented available data. Recommendations were determined by group consensus (January 1996); revisions as warranted by new data were incorporated by group consensus (February-May 1996). CONCLUSIONS: Recent data on HIV pathogenesis, methods to determine plasma HIV RNA, clinical trial data, and availability of new drugs point to the need for new approaches to treatment. Therapy is recommended based on CD4+ cell count, plasma HIV RNA level, or clinical status. Preferred initial drug regimens include nucleoside combinations; at present protease inhibitors are probably best reserved for patients at higher progression risk. For treatment failure or drug intolerance, subsequent regimen considerations include reasons for changing therapy, available drug options, disease stage, underlying conditions, and concomitant medication(s). Therapy for primary (acute) infection, high-risk exposures to HIV, and maternal-to-fetal transmission are also addressed. Therapeutic approaches need to be updated as new data continue to emerge.

Antiviral Agents↗

Nevirapine, zidovudine, and didanosine compared with zidovudine and didanosine in patients with HIV-1 infection. A randomized, double-blind, placebo-controlled trial. National Institute of Allergy and Infectious Diseases AIDS Clinical Trials Group Protocol 241 Investigators.

OBJECTIVE: To study the addition of a third human immunodeficiency virus type 1 (HIV-1) reverse transcriptase inhibitor, nevirapine, to the combination of zidovudine and didanosine. DESIGN: A 48-week, randomized, double-blind, placebo-controlled trial at 16 AIDS (acquired immunodeficiency syndrome) Clinical Trials Units. PATIENTS: 398 adults who had HIV-1 infection, had 350 or fewer CD4+ T lymphocytes/mm3, and had had more than 6 months of previous nucleoside therapy. INTERVENTION: 1) Either nevirapine or placebo (200 mg/d for 2 weeks, then 400 mg/d thereafter) and 2) open-label zidovudine (600 mg/d) and didanosine (400 mg/d for patients weighing > or = 60 kg). MEASUREMENTS: CD4+ T lymphocyte counts, time to first HIV-1 disease progression event or death, adverse events, and nevirapine levels in plasma samples taken at random were measured in all patients. Plasma levels of HIV-1 RNA HIV-1 infectivity titer in peripheral blood mononuclear cells; serum p24 antigen levels; and plasma levels of zidovudine and didanosine were measured in patients enrolled at half the study sites. RESULTS: After 48 weeks of study treatment the patients assigned to the triple-combination regimen (nevirapine, zidovudine, and didanosine) had an 18% higher mean absolute CD4 cell count (95% Cl, 7% to 29%; P = 0.001), a 0.32 log10 lower mean infectious HIV-1 titer in peripheral blood mononuclear cells (Cl, 0.05 to 0.59 log10 infectious units per million cells; P = 0.023), and a 0.25 log10 lower mean plasma HIV-1 RNA level (Cl, 0.03 to 0.48 log10 RNA copies/mL; P = 0.028) than did patients assigned to the double-combination regimen (zidovudine and didanosine). Severe rashes were more common among patients assigned to receive the triple combination (9% compared with 2%; P = 0.002). Risk for disease progression did not differ between the two groups (relative hazard of the triple-combination group, 1.24 [Cl, 0.75 to 2.06]; P > 0.2), although the study had only moderate power to detect a major difference. CONCLUSIONS: Adding nevirapine to zidovudine and didanosine improved the long-term immunologic and virologic effects of therapy and was associated with severe rash among the patients studied, who had had extensive previous therapy. These results support 1) the continuing development of combinations of more than two antiretroviral drugs to increase and prolong HIV-1 suppression and 2) the potential utility of nevirapine in combination regimens.

Adult↗

A phase II study of recombinant human interferon-alpha 2a and zidovudine in patients with AIDS-related Kaposi's sarcoma. AIDS Clinical Trials Group.

To assess safety, antitumor response, and immunological and virological activity of interferon-alpha 2a and zidovudine combination therapy in patients with AIDS-related Kaposi's sarcoma, we conducted an open-label, Phase II, multicenter study. Sixty-three patients with biopsy-proven Kaposi's sarcoma and no previous interferon-alpha therapy received zidovudine 600 mg/day and interferon-alpha 2a 18 x 10(6) U/day. The median duration of follow-up was 49 weeks. Of 62 evaluable patients, 25 (40%; 95% confidence interval, 0.28-0.52) showed a complete (26%) or partial (15%) antitumor response. Eight of 30 patients (27%) with < 100 CD4 cells/mm3 and 17 of 32 patients (53%) with > or = 100 CD4 cells/mm3 had a response. The median time to response was 36 weeks. Of the 25 patients with a response, four developed tumor progression. The median duration of response was 22.4 weeks. Eight patients (13%) developed another AIDS-defining event and 13 (21%) died. The major toxicities included anemia (16%), neutropenia (27%), elevated serum transaminases (16%), weight loss (16%), malaise (14%), fatigue (14%), fever (10%), and headache (6%). Therapy with intermediate-dose interferon-alpha 2a and zidovudine resulted in tumor regression in patients with AIDS-related Kaposi's sarcoma who had a wide range of CD4 cell counts; this therapy was relatively well tolerated.

Acquired Immunodeficiency Syndrome↗

Didanosine reduces atevirdine absorption in subjects with human immunodeficiency virus infections.

Atevirdine is a nonnucleoside reverse transcriptase inhibitor with in vitro activity against human immunodeficiency virus type 1 and is currently in phase II clinical trials. Atevirdine is most soluble at a pH of < 2, and therefore, normal gastric acidity is most likely necessary for optimal bioavailability. Because of the rapid development of resistance in vitro, atevirdine is being evaluated in combination with didanosine and/or zidovudine in both two- and three-drug combination regimens. To examine the influence of concurrent didanosine (buffered tablet formulation) on the disposition of atevirdine, 12 human immunodeficiency virus type 1-infected subjects (mean CD4+ cell count, 199 cells per mm3; range, 13 to 447 cells/mm3) participated in a three-way, partially randomized, crossover, single-dose study to evaluate the pharmacokinetics of didanosine and atevirdine when each drug was given alone (treatments A and B, respectively) versus concurrently (treatment C). Concurrent administration of didanosine and atevirdine significantly reduced the maximum concentration of atevirdine in serum from 3.45 +/- 2.8 to 0.854 +/- 0.33 microM (P = 0.004). Likewise, the mean atevirdine area under the concentration-time curve from 0 to 24 h after administration of the combination was reduced to 6.47 +/- 2.2 microM.h (P = 0.004) relative to a value of 11.3 +/- 4.8 microM.h for atevirdine alone. Atevirdine had no statistically significant effect on the pharmacokinetic parameters of didanosine. Concurrent administration of single doses of atevirdine and didanosine resulted in a markedly lower maximum concentration of atevirdine in serum and area under the concentration-time curve, with a minimal effect on the disposition of didanosine. It is unknown whether an interaction of similar magnitude would occur under steady-state conditions; thus, combination regimens which include both atevirdine and didanosine should be designed so that their administration times are separated. Since the duration of the buffering effect of didanosine formulations is unknown, atevirdine should be given prior to didanosine.

Adolescent↗

Synergy, activity and tolerability of zidovudine and interferon-alpha in patients with symptomatic HIV-1 infection: AIDS Clincal Trial Group 068.

Thirty-four subjects with symptomatic HIV-1 infection, p24 antigenaemia, and CD4 cell counts > 200/mm3 were randomly assigned to receive treatment with either zidovudine (ZDV) orally, interferon-alpha (IFN-alpha) subcutaneously, or both at respective low (200 mg ZDV/ 2 million international units IFN-alpha (MIU)), middle (400 mg/4 MIU) or high (600 mg/6 MIU) daily dose levels for 12 weeks. Thereafter, all patients received combination therapy at the initially assigned dose level to a total of 96 weeks. This design permitted analysis by the combination index (CI) method, which demonstrated antiretroviral synergy between ZDV and IFN-alpha with respect to p24 antigen suppression. Over the first 12 weeks, combination therapy was acceptably tolerated, more so than IFN-alpha monotherapy, and it was significantly more active in suppressing antigenaemia than either of the monotherapies. Similarly, the high-dose combination was the most active dose level over weeks 12 to 96. Combination ZDV/IFN-alpha at the optimal dose level defined by this trial merits further study. In addition, the CI design strategy employed here may be useful for the investigation of new antiretroviral combinations.

Administration, Cutaneous↗

A comparison of immediate with deferred zidovudine therapy for asymptomatic HIV-infected adults with CD4 cell counts of 500 or more per cubic millimeter. AIDS Clinical Trials Group.

BACKGROUND: The clinical benefits of zidovudine remain unproved in patients with asymptomatic human immunodeficiency virus (HIV) infection when CD4 cell counts exceed 500 per cubic millimeter. We compared zidovudine therapy given immediately with deferred therapy in such subjects. METHODS: Beginning in 1987, subjects with asymptomatic HIV infection and 500 or more CD4 cells per cubic millimeter were randomly assigned to receive placebo or zidovudine (either 500 or 1500 mg per day, starting immediately). In 1989, the study was modified so that open-label treatment with 500 mg of zidovudine per day (deferred therapy) was offered when CD4 cell counts fell below 500 per cubic millimeter. The study end points included overall survival, survival free of the acquired immunodeficiency syndrome (AIDS), toxic effects, and changes in CD4 cell counts. RESULTS: There were 1637 subjects who could be evaluated: 547 in the deferred-therapy group, 549 in the group receiving 500 mg of zidovudine immediately, and 541 in the 1500-mg group. The subjects were followed for up to 6.5 years (group medians, 4.8, 4.8, and 4.9, respectively). There was no significant difference in AIDS-free survival in the deferred-therapy group as compared with the low-dose or high-dose groups (81 cases of progression to AIDS or death vs. 81 and 74, respectively; P = 0.95 and P = 0.13) or in overall survival (51 deaths vs. 47 and 46; P = 0.25 and P = 0.16). The decline in CD4 cells was slower in both immediate-therapy groups than in the deferred-therapy group (P < 0.001 for both). Adverse effects were uncommon, and before the study modification their incidence was similar among the treatment groups, but severe anemia and granulocytopenia were more frequent in the 1500-mg group than in the deferred-therapy group (P < 0.001). CONCLUSIONS: In asymptomatic, HIV-infected adults with 500 or more CD4 cells per cubic millimeter, treatment with zidovudine slows the decline in the CD4 cell count but does not significantly prolong either AIDS-free or overall survival. These results do not encourage the routine use of zidovudine monotherapy in this population.

Acquired Immunodeficiency Syndrome↗

Zidovudine compared with didanosine in patients with advanced HIV type 1 infection and little or no previous experience with zidovudine. AIDS Clinical Trials Group.

BACKGROUND: We conducted a trial to compare treatment with zidovudine or didanosine in patients with advanced human immunodeficiency virus type 1 (HIV-1) infection who had received little or no previous therapy with zidovudine. METHODS: Six hundred seventeen patients with acquired immunodeficiency syndrome (AIDS), advanced AIDS-related complex (CD4 cell count, < or = 0.30 x 10(9)/L [300/microL]), or asymptomatic HIV (CD4 cell count, < or = 0.20 x 10(9)/L) received zidovudine, 500 mg/d of didanosine, or 750 mg/d of didanosine in a randomized, double-blind allocation, with cross-over to alternative medication after development of an end point or serious toxic effect. To be eligible, patients must have received either no or up to 16 weeks of zidovudine therapy before entry into the study. Primary end points were development of a new AIDS-defining event or death. Secondary clinical end points were new or recurrent AIDS-defining events, or death, and survival. RESULTS: In the study as a whole, there were no differences in the relative risks (RRs) of the development of end points between treatment groups. However, there was a strong interaction between the relative efficacies of zidovudine and didanosine and previous experience with zidovudine. Among 380 patients with no previous zidovudine therapy, zidovudine was more effective than 750 mg/d of didanosine (RR, 1.43; 90% confidence interval [CI], 1.02 to 2.00), with a similar trend for zidovudine compared with 500 mg/d of didanosine (RR, 1.21; 90% CI, 0.86 to 1.71). However, among 118 patients with more than 8 weeks but no more than 16 weeks of previous zidovudine therapy, 500 mg/d of didanosine was more effective than zidovudine (RR, 0.48; 90% CI, 0.27 to 0.86); there was a similar trend for increased effectiveness of 750 mg/d of didanosine compared with zidovudine (RR, 0.61; 90% CI, 0.36 to 1.03). Among 119 patients who had some but no more than 8 weeks of previous zidovudine therapy, there were no significant differences among the treatment arms. Similar findings were noted in the analysis of the two secondary clinical end points. No significant differences were found in efficacy between the groups receiving 500 and 750 mg/d of didanosine. The major toxic effect associated with zidovudine was hematopoietic (granulocytopenia) and that associated with didanosine was pancreatitis (dosage, 750 mg/d). CONCLUSIONS: In patients with advanced HIV disease, zidovudine appears to be more effective than didanosine as initial therapy; however, some patients with advanced HIV disease may benefit from a change to didanosine therapy after as little as 8 to 16 weeks of therapy with zidovudine.

AIDS-Related Opportunistic Infections↗

Combination therapy with recombinant human soluble CD4-immunoglobulin G and zidovudine in patients with HIV infection: a phase I study.

To determine the effect of zidovudine (ZDV) on the pharmacokinetic disposition of recombinant soluble CD4 immunoglobulin G (rCD4-IgG) and to evaluate the safety and preliminary activity of concurrent administration of ZDV with rCD4-IgG, we undertook an open-label, dose-escalating, 12-week study. The regimens of intravenous rCD4-IgG and oral ZDV we used were (a) 300 micrograms/kg rCD4-IgG twice per week and 300 mg ZDV per day, (b) 300 micrograms/kg rCD4-IgG twice per week and 600 mg ZDV per day, (c) 1,000 micrograms/kg rCD4-IgG twice per week and 300 mg ZDV per day, (d) 1,000 micrograms/kg rCD4-IgG twice per week and 600 mg ZDV per day, and (e) 3,000 micrograms/kg rCD4-IgG twice per week and 300 mg ZDV per day. Subjects were recruited from three AIDS clinical trials units. Forty-one patients with HIV infection who had CD4 cell counts < or = 500 cells/mm3 and < 120 days of previous ZDV therapy participated. Pharmacokinetic interactions were assessed with the second regimen. Mean calculated peak serum rCD4-IgG concentrations were 5.47 micrograms/ml with ZDV and 8.28 micrograms/ml without ZDV, with serum half-lives of 34.2 and 32.0 h, respectively. Antibodies to rCD4-IgG were not detected. Seven episodes of severe adverse events occurred in five patients: one episode each of severe nausea, fever, or abnormal liver function tests and four episodes of severe neutropenia. Mean hemoglobin and neutrophil counts decreased, and mean platelet counts increased in all regimens, but there were no significant differences among regimens, rCD4-IgG dose, or ZDV dose.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Combination and monotherapy with zidovudine and zalcitabine in patients with advanced HIV disease. The NIAID AIDS Clinical Trials Group.

OBJECTIVE: To compare the safety and efficacy of continuing zidovudine therapy with that of zalcitabine alone or zalcitabine and zidovudine used together. DESIGN: A randomized, double-blind, controlled trial. SETTING: AIDS Clinical Trials units and National Hemophilia Foundation sites. PATIENTS: 1001 patients with symptomatic human immunodeficiency (HIV) disease and 300 or fewer CD4 cells/mm3 or asymptomatic HIV disease and 200 or fewer CD4 cells/mm3 who had tolerated zidovudine therapy for 6 months or more. INTERVENTION: Patients were randomly assigned to receive zidovudine, 600 mg/d; zalcitabine, 2.25 mg/d; or zidovudine, 600 mg/d, and zalcitabine, 2.25 mg/d. MEASUREMENTS: The primary end point was time to disease progression or death. RESULTS: The median follow-up time was 17.7 months. The estimated 12-month event-free rates were 70%, 67%, and 73%, respectively, for the zidovudine, zalcitabine, and combination groups (P = 0.26). A trend analysis showed significantly lower progression rates for combination therapy compared with zidovudine therapy as the pretreatment CD4 cell count increased (P = 0.027). For patients with 150 or more CD4 cells/mm3, those receiving combination therapy were less likely to have disease progression or to die than were those receiving zidovudine (relative risk, 0.51; 95% CI, 0.28 to 0.93; P = 0.029). We observed no difference between the zalcitabine and zidovudine groups (relative risk, 0.74; CI, 0.40 to 1.36; P = 0.33). For patients with 50 to 150 CD4 cells/mm3 or fewer than 50 CD4 cells/mm3, we found no differences among the treatment groups (P = 0.69 and P = 0.57, respectively). Severe toxic effects occurred less frequently among patients with 150 or more CD4 cells/mm3. CONCLUSIONS: We found no overall benefits of zalcitabine used alone or with zidovudine. However, a trend analysis suggested a better outcome for combination therapy compared with zidovudine as the pretreatment CD4 cell count increased.

Acquired Immunodeficiency Syndrome↗

Rapid oral desensitization for sulfonamides in patients with the acquired immunodeficiency syndrome.

BACKGROUND: A prospective case series was undertaken in a university teaching hospital. OBJECTIVE: To evaluate the safety and efficacy of two oral desensitization procedures for sulfonamides in patients with the acquired immunodeficiency syndrome (AIDS). METHODS: A rapid oral desensitization protocol to sulfadiazine (2.5 hours) or trimethoprim-sulfamethoxazole (8 hours) was used. Increasing volumes of either drug were given orally every 15 minutes until 1 g of sulfadiazine or 1443.3 mg of trimethoprim-sulfamethoxazole was reached. RESULTS: Nine of 13 (69%) patients were able to tolerate sulfadiazine for a period of 10 to 730 days (mean: 184 days). This was achieved in eight patients after the first attempt, in one after the second attempt. Five patients failed after the first attempts with or without premedications. Two of these five failed despite two attempts. Two patients relapsed 21 days after responding to rapid desensitization. Three patients underwent a successful 5 to 6-day slow desensitization protocol with premedications with high dose corticosteroids and antihistamines despite failures after two attempts with rapid desensitization in two of these patients and relapse in one. CONCLUSIONS: Overall, 11 of 13 (85%) patients were successfully desensitized to sulfonamides using both rapid and slow methods. No life-threatening reactions occurred. Premedications with oral antihistamines and corticosteroids may be needed to control and prevent early occurrences of rash or pruritus during desensitization. In those who fail rapid desensitization, the slow method with premedications is an alternative.

Acquired Immunodeficiency Syndrome↗

Combination antiretroviral therapy for HIV infection.

Despite recent disappointment with antiretroviral agents, investigators continue to examine combination therapy with agents that target the same or different stages of the HIV life cycle. Initial studies suggest that when therapy is started early in the course of infection, certain combinations may be better than single-drug regimens in reducing viral burden and delaying the onset of drug resistance.

Antiviral Agents↗