Low rate of CMV end-organ disease in HIV-infected patients despite low CD4+ cell counts and CMV viremia: results of ACTG protocol A5030.

PURPOSE: To describe cytomegalovirus (CMV) end-organ disease (EOD) rate in AIDS patients with low CD4+ cell count despite HAART who were enrolled in a randomized, placebo-controlled trial of preemptive valganciclovir (VGCV) to prevent CMV EOD in those with CMV viremia. METHODS: Subjects (N = 338) were HIV-infected with CD4+ count <100 cells/mm3, plasma HIV RNA >400 copies/mL, and on stable or no HAART. All underwent plasma CMV DNA PCR testing every 8 weeks (Step 1); those with detectable CMV DNA were randomized to VGCV or placebo (Step 2). RESULTS: Plasma CMV DNA was detected in 68 (20%), of whom 4 developed CMV EOD. During Step 1, 53 died. Of the 47 who entered Step 2 (24 VGCV, 23 placebo), CMV EOD was diagnosed in 10 (4 VGCV, 6 placebo) and 15 died (7 VGCV, 8 placebo). Of those randomized to placebo, 14% were diagnosed with CMV EOD at 12 months. CONCLUSIONS: We observed a lower CMV EOD rate among subjects receiving HAART than predicted based on published literature. However, mortality was high in this study. Our findings suggest that preemptive anti-CMV therapy in patients with persistently low CD4+ cell counts in the current treatment era may not be warranted given the low incidence of CMV EOD and high all-cause mortality observed in this study population.

Silencing p21(Waf1/Cip1/Sdi1) expression increases gene transduction efficiency in primitive human hematopoietic cells.

Adult hematopoietic and other tissue stem cells have highly constrained cell cycling that limits their susceptibility to standard gene therapy vectors, which depend upon chromosomal integration. Using cytokine cocktails to increase transduction efficiency often compromises subsequent stem cell function in vivo. We previously showed that p21(Waf1/Cip1/Sdi1) (p21) mediates stem cell quiescence in vivo and decreasing its expression ex vivo leads to an expansion of stem cell pool in vivo. Here, we report that application of p21 specific siRNA increased the gene transduction efficiency in hematopoietic stem cells while preserving cell multipotentiality. Both types of siRNA, synthesized siRNA and transcribed shRNA, reduced p21 expression in target cells by 85-98%. The effect of RNAi in these cells was transient and the level of p21 mRNA returned to base line 14-28 days after siRNA treatment. This brief interval of reduction, however, was sufficient to increase transduction efficiency to two- to four-fold in cell cultures, and followed by a seven- to eight-fold increase in mice. The RNAi treated, lentivector-transduced CD34+ cells retained multipotentiality as assessed in vitro by colony formation assay and in vivo by NOD/SCID mouse transplantation assay. Reduction of p21 resulted in an increased chromosomal integration of lentivector into target cellular DNA. Taken together, both synthesized and transcribed siRNA knocked down p21 expression in human CD34+ hematopoietic stem/progenitor cells. Silencing p21 expression increased gene transduction efficiency and vector integration while retaining stem cell multipotentiality. Thus, RNAi targeting of p21 is a useful strategy to increase stem cell gene transfer efficiency. Decreasing p21 expression transiently while increasing gene-transfer vector integration may ultimately facilitate clinical applications of gene therapy.

Human immunodeficiency virus type 1 RNA in peripheral blood mononuclear cells of patients receiving prolonged highly active antiretroviral therapy.

The levels of early spliced mRNA and genomic RNA of human immunodeficiency virus (HIV) type 1 in peripheral blood mononuclear cells (PBMC) of 14 patients who were receiving highly active combination antiretroviral therapy for > or =116 weeks were determined. The level of viral genomic RNA was below the level of detection in the plasma of these patients (<50 copies/mL), but cell-associated viral tat, rev, and nef mRNA were detected in 86% (12 of 14) of the patients. Cell-associated viral genomic RNA was detected in 57% (8 of 14) of the patients. Early viral spliced mRNA was detected in the PBMC of all patients who had positive results of testing for HIV-1 genomic RNA, and the level of viral genomic RNA in these patients was 34-2214 copies per 10(6) cells.

Sequencing of cytomegalovirus UL97 gene for genotypic antiviral resistance testing.

The widespread use of ganciclovir (GCV) to treat cytomegalovirus (CMV) infections in immunosuppressed patients has led to the development of drug resistance. Phenotypic assays for CMV drug resistance are presently too time-consuming to be therapeutically useful. To support the development of genotypic assays for GCV resistance, the complete sequences of the UL97 phosphotransferase genes in 28 phenotypically GCV-sensitive CMV clinical isolates were determined. The gene was found to be highly conserved, with nucleotide sequence identity among strains ranging from 98.6 to 100% and amino acid sequence identity of >99%. Primers for a genotypic assay were designed to amplify codons 400 to 707, because all known UL97 mutations conferring drug resistance occur at three sites within this region. This part of the UL97 gene was amplified from over 50 clinical isolates, and two sequencing reactions for the coding strand were successfully used to identify GCV resistance mutations. This genotypic assay can be performed in 48 h using genomic DNA extracted from cell monolayers at very low levels of virus infectivity, thus rapidly providing therapeutically useful results.

Comparison of quantitative and qualitative PCR assays for cytomegalovirus DNA in plasma.

We analyzed the performance characteristics of the qualitative AMPLICOR CMV Test (Roche Molecular Systems, Pleasanton, Calif.) and quantitative COBAS AMPLICOR CMV MONITOR Test (Roche Molecular Systems) assays and compared the performance of the AMPLICOR quantitative assay with an in-house-developed cytomegalovirus (CMV) DNA PCR assay. The quantitative AMPLICOR assay was found to be more sensitive than the qualitative AMPLICOR assay. The quantitative AMPLICOR assay has a lower limit of sensitivity of 400 CMV DNA copies/ml of plasma and is linear to 50,000 CMV DNA copies/ml of plasma. Compared to the in-house PCR assay, the AMPLICOR quantitative assay gave lower viral load values at all concentrations tested, but the difference between the two assays was not consistent across the entire dynamic range of the AMPLICOR quantitative assay. At the lower end of the assay, the viral load values obtained with the in-house PCR assay were three- to fivefold (0.5 to 0.7 log units) higher than those measured with the AMPLICOR assay. At higher input concentrations, the differences between the two assays approached 10-fold. This direct comparison of the in-house assay and the quantitative AMPLICOR assay provides the ability to compare previously published in-house data with an assay widely available for future research and clinical monitoring of patients with CMV infections.

A fusion inhibitor (FP-21399) for the treatment of human immunodeficiency virus infection: a phase I study.

FP-21399 is a bis(disulfonaphthalene) derivative that prevents human immunodeficiency virus (HIV) infection of uninfected cells by blocking entry of the virus. FP-21399 shows an affinity for lymph nodes. In this phase I study, FP-21399 was administered intravenously over 1 h as a single dose (0.9, 1.7, 2.8, and 4.2 mg/kg) or as a once-weekly infusion (1, 2, and 3 mg/kg) for 4 consecutive weeks to 34 HIV-1 infected patients with CD4(+) cell counts of 50-400 cells/microL. Concomitant antiretroviral therapy was permitted but not required. The most frequent adverse events involved the transient, dose-dependent appearance of drug- or metabolite-related color in the urine and skin. Plasma drug levels were linear with dose. The drug was cleared, with an elimination half-life of 4 h and a terminal half-life of 1.5-2 days; the terminal half-life represented redistribution and clearance from tissues. FP-21399 administered weekly for 4 weeks was well tolerated. Further studies are necessary to define the role of this fusion inhibitor in the treatment of HIV infection.

Characterization of an acyclovir-resistant herpes simplex virus type 2 strain isolated from a premature neonate.

Acyclovir resistance is not a recognized problem among neonates with perinatal herpes simplex virus (HSV) infection. A premature newborn with neurocutaneous HSV infection was treated for 21 days with acyclovir. Disseminated disease recurred 8 days later. A recurrent isolate was resistant to acyclovir and lacked thymidine kinase activity on the basis of a frameshift mutation in the thymidine kinase (tk) gene. Compared with the sensitive isolate obtained during primary infection, replication of the resistant isolate was reduced on primary and permanent cells and even further impaired on cells deleted for cellular tk. The resistant isolate lacked virulence in a murine model of genital infection. Acyclovir-resistant HSV-2 mutants can develop rapidly in neonatal infection and cause clinically significant disease, despite decreased replication in vitro and attenuated virulence in an animal model.

Enhancement of the basal-level activity of HIV-1 long terminal repeat by HIV-1 nucleocapsid protein.

Two HIV-1 proteins, Tat and NCp7 (NC), have zinc finger-like structures. NC is a virion protein and has been shown to accumulate in the nucleus 8 h postinfection. Since transcription factors with zinc fingers assist the transcriptional activity of both RNA polymerases II and III, we examined the effect of NC on HIV-1 LTR-directed gene expression. The HIV-1 NC binds to the HIV-1 LTR and results in a mobility shift in polyacrylamide gel electrophoresis. Competition assays with cold probes revealed that the binding of NC and formation of a DNA-protein complex could be prevented by the addition of excess unlabeled LTR self-probe, but not the HIV-1 V3 envelope gene. The DNase I footprint analysis showed that NC binds to six regions within HIV-1 LTR, four of which are near the transcription start site. The NC alone enhances LTR basal-level activity in RNA runoff experiments. When the general transcription factors (GTFs) were added in the assay, NC enhances NF-kappaB, Sp1, and TFIIB-induced HIV-1 LTR-directed RNA transcription. RNA transcription directed by the adenovirus major late promoter, however, is not significantly affected by NC in the cell-free system. Transient transfection of human T lymphocytes with the plasmids containing HIV-1 nc or gag showed enhancement of LTR-CAT activity. Moreover, transfection of HIV-1 provirus containing mutations in NC zinc-finger domains dramatically decreases the enhancement activity in human T cells, in which HIV-1 LTR is stably integrated into the cellular genome. These observations show that NC binds to HIV-1 LTR and cooperatively enhances GTFs and NF-kappaB induced HIV-1 LTR basal-level activity. NC may play the role of a nucleation protein, which binds to LTR and enhances basal-level transcription by recruiting cellular transcription factors to the HIV-1 promoter in competition with cellular promoters.

A standardized plaque reduction assay for determination of drug susceptibilities of cytomegalovirus clinical isolates.

Twelve laboratories collaborated in formulating and testing a standardized plaque reduction assay for cytomegalovirus (CMV) cell-associated clinical isolates. Four characterized and plaque-purified CMV strains, as well as six coded clinical isolates obtained after antiviral therapy, were distributed and tested. Good agreement was obtained for four of the clinical isolates, but a broad distribution of results was obtained for two isolates. Analysis of these results indicates the problems associated with clinical isolates, including the large genetic variability and the highly cell-associated phenotype. This collaborative effort, by addressing these problems, represents a significant step toward the development of a standardized assay.

Decreased processivity of human immunodeficiency virus type 1 reverse transcriptase (RT) containing didanosine-selected mutation Leu74Val: a comparative analysis of RT variants Leu74Val and lamivudine-selected Met184Val.

We previously showed that a didanosine-selected mutation in pNL4-3 background conferred a replication disadvantage on human immunodeficiency virus type 1, resulting in a loss of replication fitness. This work has been extended by showing that a recombinant virus with the HXBc2 backbone and reverse transcriptase (RT) fragments from pNL4-3 containing the Leu74Val mutation produce decreasing amounts of p24 antigen over a 3-week period. The HXBc2 recombinant containing the wild-type RT from pNL4-3 replicated efficiently. When the virion-associated RT containing the Leu74Val mutation was used in an RT processivity assay with homopolymer RNA template-primer, poly(A), and oligo(dT), the RT with altered Leu74Val mutation was less processive, generating fewer cDNA products in comparison to wild-type pNL4-3 RT. The replication kinetics and RT processivity of the mutant with the Leu74Val mutation were compared to those of a lamivudine-selected mutant Met184Val. In replication kinetics assays, mutant Leu74Val replicated slower than the mutant Met184Val. In a processivity assay, the mutant RTs from both viruses show comparable decreases in processivity. These observations provide biochemical evidence of decreased processivity to support the decrease in replication fitness observed with the Leu74Val or Met184Val mutations.

Interstrain variation in the human cytomegalovirus DNA polymerase sequence and its effect on genotypic diagnosis of antiviral drug resistance. Adult AIDS Clinical Trials Group CMV Laboratories.

The polymerase (pol) coding sequence was determined for 40 independent clinical cytomegalovirus isolates sensitive to ganciclovir and foscarnet. Sequence alignments showed >98% interstrain homology and amino acid variation in only 4% of the 1, 237 codons. Almost all variation occurred outside of conserved functional domains where resistance mutations have been identified.

Phase I studies of hypericin, the active compound in St. John's Wort, as an antiretroviral agent in HIV-infected adults. AIDS Clinical Trials Group Protocols 150 and 258.

BACKGROUND: Hypericin, the active compound in St. John's Wort, has antiretroviral activity in vitro. Many HIV-infected persons use St. John's wort. OBJECTIVE: To evaluate the safety and antiretroviral activity of hypericin in HIV-infected patients. DESIGN: Phase I study. SETTING: Four clinical research units. PATIENTS: 30 HIV-infected patients with CD4 counts less than 350 cells/mm3. INTERVENTION: Intravenous hypericin, 0.25 or 0.5 mg/kg of body weight twice weekly or 0.25 mg/kg three times weekly, or oral hypericin, 0.5 mg/kg daily. MEASUREMENTS: Safety was assessed at weekly visits. Antiretroviral activity was assessed by changes in HIV p24 antigen level, HIV titer, HIV RNA copies, and CD4 cell counts. RESULTS: Of the 30 patients who were enrolled, 16 discontinued treatment early because of toxic effects. Severe cutaneous phototoxicity was observed in 11 of 23 (48% [95% CI, 27% to 69%]) evaluable patients, and dose escalation could not be completed. Virologic markers and CD4 cell count did not significantly change. CONCLUSIONS: Hypericin caused significant phototoxicity and had no antiretroviral activity in the limited number of patients studied.

Rapid ganciclovir susceptibility assay using flow cytometry for human cytomegalovirus clinical isolates.

Rapid, quantitative, and objective determination of the susceptibilities of human cytomegalovirus (HCMV) clinical isolates to ganciclovir has been assessed by an assay that uses a fluorochrome-labeled monoclonal antibody to an HCMV immediate-early antigen and flow cytometry. Analysis of the ganciclovir susceptibilities of 25 phenotypically characterized clinical isolates by flow cytometry demonstrated that the 50% inhibitory concentrations (IC50s) of ganciclovir for 19 of the isolates were between 1.14 and 6.66 microM, with a mean of 4.32 microM (+/-1.93) (sensitive; IC50 less than 7 microM), the IC50s for 2 isolates were 8.48 and 9.79 microM (partially resistant), and the IC50s for 4 isolates were greater than 96 microM (resistant). Comparative analysis of the drug susceptibilities of these clinical isolates by the plaque reduction assay gave IC50s of less than 6 microM, with a mean of 2.88 microM (+/-1.40) for the 19 drug-sensitive isolates, IC50s of 6 to 8 microM for the partially resistant isolates, and IC50s of greater than 12 microM for the four resistant clinical isolates. Comparison of the IC50s for the drug-susceptible and partially resistant clinical isolates obtained by the flow cytometry assay with the IC50s obtained by the plaque reduction assay showed an acceptable correlation (r2 = 0.473; P = 0.001), suggesting that the flow cytometry assay could substitute for the more labor-intensive, subjective, and time-consuming plaque reduction assay.

Expression of the CD8alpha beta-heterodimer on CD8(+) T lymphocytes in peripheral blood lymphocytes of human immunodeficiency virus- and human immunodeficiency virus+ individuals.

CD8(+) T lymphocytes play a pivotal role in controlling human immunodeficiency virus (HIV)-1 replication in vivo. We have performed four-color flow cytometric analysis of CD8(+) peripheral blood lymphocytes (PBL) from 21 HIV-1 seronegative and 103 seropositive individuals to explore the phenotypic heterogeneity of CD8beta-chain expression on CD8(+) T lymphocytes and to clarify how its expression on CD8(+) T lymphocytes may relate to acquired immunodeficiency syndrome (AIDS) clinical progression. We showed that the single monoclonal antibody (MoAb) 2ST8-5H7, directed against the CD8alpha beta-heterodimer, identifies CD8(+) T lymphocytes as effectively as the conventional combination of anti-CD3 and anti-CD8alpha antibodies. However, we detected a significantly lower mean fluorescence (MF) of anti-CD8alpha beta staining on PBL from HIV-1 seropositive donors as compared with seronegative donors. In fact, CD8(+) T lymphocytes from HIV-1-infected individuals with the lowest CD4 counts showed the lowest levels of CD8alpha beta MF. To explore further this change in CD8alpha beta expression, we assessed the expression of 14 different cell surface molecules on CD8alpha beta+ T lymphocytes of PBL from 11 HIV-1 seronegative and 22 HIV-1 seropositive individuals. The MF of anti-CD8alpha beta staining was significantly reduced on CD8(+) T lymphocyte subsets that showed immunophenotypic evidence of activation. The subset of lymphocytes expressing low levels of CD8alpha beta expressed higher levels of activation, adhesion, and cytotoxic-associated molecules and was predominantly CD45RO+ and CD28(-). Finally, we monitored the expression of the CD8alpha beta-heterodimer on PBL of eight HIV-1-infected individuals over a 16-week period after the initiation of highly active antiretroviral therapy (HAART), including zidovudine (ZDV), lamivudine (3TC), and indinavir (IDV), and found a significant increase in the expression of the CD8alpha beta-heterodimer. These results suggest that antibodies recognizing the CD8alpha beta-heterodimer are useful tools to specifically identify CD8(+) T lymphocytes. Moreover, the quantitative monitoring of CD8alpha beta expression allows the detection of discrete CD8(+) T lymphocyte subsets and may be useful for assessing the immune status of individuals infected with HIV-1.

Sorivudine versus acyclovir for treatment of dermatomal herpes zoster in human immunodeficiency virus-infected patients: results from a randomized, controlled clinical trial. Collaborative Antiviral Study Group/AIDS Clinical Trials Group, Herpes Zoster Study Group.

The present randomized, double-blind, placebo-controlled, multicenter clinical trial was designed to compare the efficacy and tolerability of sorivudine [1-beta-D-arabinofuranosyl-E-(2-bromovinyl)uracil] and acyclovir for the treatment of dermatomal herpes zoster in human immunodeficiency virus (HIV)-seropositive patients. A total of 170 HIV-seropositive adults presenting with herpes zoster (confirmed by direct fluorescent-antigen testing and/or viral culture) were enrolled and randomized to receive a 10-day course of orally administered sorivudine (40 mg once daily plus acyclovir placebos) or acyclovir (800 mg five times daily plus sorivudine placebo). Patients were monitored daily to document the events of cutaneous healing, pain, zoster-related complications, and drug-related adverse events. Patients were reassessed on days 21 and 28 and then once monthly for 1 year. The primary efficacy endpoint was time to the cessation of new vesicle formation. Secondary efficacy endpoints included times to other events of cutaneous healing, resolution of pain, and frequency of dissemination and zoster recurrence. In a multivariate analysis, sorivudine was superior to acyclovir for reducing the times to the cessation of new vesicle formation (relative risk [RR] = 1.54, 95% confidence interval [CI] = 1.00 to 2.36; P = 0.049) and total lesion crusting (RR = 1.48, 95% CI = 1.07 to 2.04; P = 0.017). In a univariate analysis, there was a trend favoring sorivudine for the cessation of new vesicle formation (median of 3 versus 4 days; P = 0.07) and a significant advantage for time to total lesion crusting (median of 7 versus 8 days; P = 0.02). The time to the resolution of zoster-associated pain, the frequency of dissemination, and the frequency of zoster recurrence were not different between the two treatment groups. Both drugs were well tolerated. Sorivudine is an effective drug for the treatment of herpes zoster in HIV-infected patients and results in accelerated cutaneous healing when compared with acyclovir therapy.

Flow cytometric determination of ganciclovir susceptibilities of human cytomegalovirus clinical isolates.

A flow cytometric assay has been developed for the measurement of susceptibilities to ganciclovir of laboratory strains and clinical isolates of human cytomegalovirus (HCMV). The assay uses fluorochrome-labeled monoclonal antibodies to HCMV immediate-early and late antigens to identify HCMV-infected cells and flow cytometry to detect and quantitate the number of antigen-positive cells. By this assay, the 50 and 90% inhibitory concentrations (IC50 and IC90, respectively) of ganciclovir for the AD169 strain of HCMV were 1.7 and 9.2 microM, respectively, and the IC50 for the ganciclovir-resistant D6/3/1 derivative of the AD169 strain was greater than 12 microM. The ganciclovir susceptibilities of 17 HCMV clinical isolates were also determined by flow cytometric analysis of the effect of ganciclovir on late-antigen synthesis in HCMV-infected cells. The average IC50 of ganciclovir for drug-sensitive HCMV clinical isolates was 3.79 microM (+/-2.60). The plaque-reduction assay for these clinical isolates yielded an average IC50 of 2.80 microM (+/-1.46). Comparison of the results of the flow cytometry assays with those obtained from the plaque-reduction assays demonstrated acceptable bias and precision. Flow cytometric and plaque-reduction analysis of cells infected with ganciclovir-resistant clinical isolates failed to show a reduction in the percentage of late-antigen-positive cells or PFU, even at 96 microM ganciclovir. The flow cytometric assay for determining ganciclovir susceptibility of HCMV is quantitative, and objective, and potentially automatable, and its results are reproducible among laboratories.

The bis-azo compound FP-21399 inhibits HIV-1 replication by preventing viral entry.

The bis-azo compound FP-21399 inhibits HIV-1 infection. We now show that FP-21399 acts on the HIV-1 envelope glycoprotein to prevent viral replication. This compound targets the entry step of the HIV-1 replication cycle as demonstrated by time-of-addition and single cycle viral entry assays. The entry of SIVmac239, which uses the same coreceptors (CD4/CCR5) as HIV-1, was not inhibited by FP-21399, indicating that the antiviral effect of FP-21399 is specific for the HIV-1 envelope glycoprotein and is not dependent upon the cellular receptors CD4 and CCR5. FP-21399 inhibits neither the activity of HIV-1 reverse transcriptase nor the expression of HIV-1 early mRNA. Finally, this compound inhibits gp120 shedding of the T-tropic virus. Our results suggest that the anti-HIV activity of FP-21399 is due to its interaction with HIV-1 gp120/41 complex during viral entry.

Attenuated replication of human immunodeficiency virus type 1 with a didanosine-selected reverse transcriptase mutation.

The Leu-74 to Val (Leu74Val) mutation in human immunodeficiency virus type 1 reverse transcriptase (RT) develops as a consequence of didanosine (ddI) therapy and is associated with a decreased susceptibility to ddI. In this report, we provide evidence that the ddI-associated Leu74Val mutation confers a replication disadvantage to the virus. In a series of experiments, we have shown that (i) a cloned virus with an engineered Leu74Val mutation in RT was attenuated for replication; (ii) a Val-to-Leu revertant of Leu74Val in the pNL4-3 background replicated with an efficiency similar to that of the wild-type virus; (iii) when two isolates from the same patient were compared, a clinical isolate containing mutations Leu74Val and Thr215Tyr was attenuated for replication compared to one in which the Thr215Tyr mutation alone was present; and (iv) the viruses with the Leu74Val mutation showed an 11% loss of fitness in a single passage compared to the wild-type and a mutant virus containing a Lys70Arg mutation. The loss of fitness for viruses grown in drug-free medium could result in an inability to detect a Leu74Val mutant in clinical isolates obtained post-ddI therapy. The decreased replication ability of the Leu74Val mutant virus selected by ddI therapy provides a strong rationale for the lower viral RNA levels observed with ddI therapy compared to zidovudine therapy in clinical trials.

The effect of tenidap on cytokines, acute-phase proteins, and virus load in human immunodeficiency virus (HIV)-infected patients: correlation between plasma HIV-1 RNA and proinflammatory cytokine levels.

Proinflammatory cytokines may be important in the pathogenesis of human immunodeficiency virus type 1 (HIV-1) disease. Tenidap decreases interleukin (IL)-6, IL-1, and tumor necrosis factor (TNF) production by peripheral blood mononuclear cells and decreases IL-6 plasma levels in rheumatoid arthritis patients. In this randomized double-blind study, 43 HIV-1-infected patients received tenidap (120 mg) or placebo daily for 6 weeks and then crossed over to the alternative therapy for an additional 6 weeks. Mean entry CD4 cell count was 140/microL. Analyses were performed on cytokines, acute-phase proteins, virus load, and CD4 cell counts. With the exception of small differences in plasma TNF levels, tenidap had no significant effect on these indices. Significant correlations of plasma IL-6 and TNF levels with HIV-1 RNA were noted. Six patients discontinued tenidap due to rash. The effects of tenidap in HIV-1 infection contrast to results in arthritis patients, in whom tenidap decreased plasma levels of IL-6 and acute-phase proteins.

Topotecan inhibits human immunodeficiency virus type 1 infection through a topoisomerase-independent mechanism in a cell line with altered topoisomerase I.

Topotecan (TPT), a known inhibitor of topoisomerase I, has previously been shown to inhibit the replication of several viruses. The mechanism of inhibition was proposed to be the inhibition of topoisomerase I. We report that TPT decreased replication of human immunodeficiency virus type 1 (HIV-1) in CPT-K5, a cell line with a topoisomerase I mutation. TPT inhibited production of HIV-1 RNA and p24 in CPT-K5 and wild-type cells equally effectively. The antiviral effects of TPT were observed not only in the topoisomerase-mutated CPT-K5 line but also in peripheral blood mononuclear cells (PBMC) acutely infected with clinical isolates and in OM10.1 cells latently infected with HIV and activated by tumor necrosis factor alpha. Little toxicity from TPT was noted in HIV-1-infected PBMC and in CPT-K5 and OM10.1 cells as measured by cell growth and proliferation assays. These observations suggest that TPT targets factors in virus replication other than cellular topoisomerase I and inhibits cytokine-mediated activation in latently infected cells by means other than cytotoxicity. These results suggest a potential for TPT and for other camptothecins in anti-HIV therapy alone and in combination with other antiretroviral drugs.