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OBJECTIVES: We wished to evaluate the effects of an antigranulocyte-macrophage colony-stimulating factor monoclonal antibody (KB003) on forced expiratory volume in 1 s (FEV1), asthma control and asthma exacerbations in adult asthmatics inadequately controlled by long-acting bronchodilators and inhaled/oral corticosteroids.SETTINGS: 47 ambulatory asthma care centres globally.PRIMARY OUTCOME MEASURES: Change in FEV1 at week 24.PARTICIPANTS: 311 were screened, 160 were randomised and 129 completed the study.INTERVENTIONS: 7 intravenous infusions of either 400 mg KB003 or placebo at baseline and weeks 2, 4, 8, 12, 16 and 20.PRIMARY AND SECONDARY OUTCOME MEASURES: FEV1 at week 24, asthma control, exacerbation rates and safety in all participants as well as prespecified subgroups.MAIN RESULTS: In the KB003 treated group, FEV1 at week 24 improved to 118 mL compared with 54 mL in the placebo group (p=0.224). However, FEV1 improved to 253 vs 26 mL at week 24 (p=0.02) in eosinophilic asthmatics (defined as >300 peripheral blood eosinophils/mL at baseline) and comparable improvements were seen at weeks 20 (p=0.034) and 24 (p=0.077) in patients with FEV1 reversibility ≥ 20% at baseline and at weeks 4 (p=0.029), 16 (p=0.018) and 20 (p=0.006) in patients with prebronchodilator FEV1 ≤ 50% predicted at baseline. There were no effects on asthma control or exacerbation rates. The most frequent adverse events in the KB003 group were rhinosinusitis and headache. There was no significant difference in antidrug antibody response between placebo and treated groups. There were no excess infections or changes in biomarkers known to be associated with the development of pulmonary alveolar proteinosis.CONCLUSIONS: Higher doses and/or further asthma phenotyping may be required in future studies with KB003.TRIAL REGISTRATION NUMBER: NCT01603277; Results.

A phase I/II trial of a candidate vaccine to prevent HIV infection was carried out in Bangkok, Thailand, testing AIDSVAX B/E (VaxGen, Inc., Brisbane, CA), a bivalent subunit vaccine prepared by combining recombinant gp120 from a subtype B virus (HIV-1MN) with gp120 from a subtype E virus (HIV-1A244) in alum adjuvant. The studies provide human data on the immunogenicity of various dose combination of non-subtype B vaccine antigens. The results suggest that AIDSVAX B/E is safe and immunogenic in humans. The optimal dose for humans in developing countries was 300 microg of each antigen (B and E). Clade E responses were measurably increased by immunizing with gp120 B/E over B alone. Using the B/E combination did not interfere with the response to either clade. Antibodies to AIDSVAX B/E were able to bind to oligomeric gp120 on the surface of cells infected with primary isolates of HIV-1.

Most individuals infected with HIV-1 show disease progression despite both cellular and humoral immune responses. We investigated whether immunisation of patients who had symptomless HIV-1 infection with an envelope subcomponent vaccine (MNrgp120) to augment immune response can slow progression of HIV-1 disease.In a randomised, double-blind, placebo-controlled trial, carried out in university infectious disease clinics and community infectious disease practices, we enrolled 573 HIV-infected patients with CD4 counts above 600 cells/microL (0.6 x 10(9)/L). Patients received 600 micrograms vaccine or placebo by intramuscular injection monthly for 6 months then every alternate month throughout the study. The primary endpoint was the rate of decline in CD4 count; secondary endpoints were HIV-1 RNA concentrations in plasma and minor clinical events associated with HIV. Analysis was by intention to treat.At baseline, the study participants had a mean CD4 count of 775 cells/microL (SD 172) and 89% of participants had detectable HIV RNA (200 copies/mL). These RNA-positive individuals had a median viral load of 9250 copies/mL (IQR 2670-26960). Analysis after 15 months of follow-up of the 568 subjects who had at least one CD4 count done after randomisation showed no difference between the 287 vaccine recipients and 281 placebo recipients in rate of decline of CD4 count (yearly decrease 53.8 [SE 7.6] vs 42.3 [7.6] cells/microL; ratio of mean gradients 1.27 [95% CI 0.63-2.55]) or in plasma HIV-1 RNA concentrations (por = 0.63). The study was designed with power to detect a vaccine-induced reduction in rate of decline in CD4 count of 60%; these results exclude with 95% confidence a reduction of 40% or more. More vaccine-treated patients than placebo recipients showed a 50% decrease in CD4 count (11 vs 5; relative risk 2.15 [95% CI 0.76-6.12], p = 0.13). The frequencies of HIV-related minor clinical events were similar in the two groups. Pain at the injection site was the only adverse event that occurred more frequently in vaccine-treated group.Postinfection immunisation of symptom-free HIV-infected patients with MNrgp120 vaccine did not alter HIV-1 disease progression as measured by immunological, virological, and clinical endpoints over a 15-month period.

The antiherpes agent 9-(1,3-dihydroxy-2-propoxymethyl)guanine (DHPG) is a much more potent inhibitor of herpes simplex viruses in vivo than acyclovir, yet both are equally active in vitro against these viruses. To explain this difference, studies were conducted to compare the intracellular metabolism and enzymatic phosphorylation of the two compounds. In herpes type 1 and type 2 infected cells, the levels of DHPG triphosphate were only about 2-fold greater than levels of acyclovir triphosphate at virus-inhibitory concentrations (less than or equal to microM). At concentrations greater than 2.5 microM in herpes type 1 but not in type 2 infected cells, acyclovir phosphorylation was inhibited relative to that of DHPG. When drug was removed after 6 hr from infected cells, acyclovir triphosphate rapidly degraded to acyclovir and was excreted into the culture medium. In contrast, DHPG triphosphate persisted at 60-70% of the original level for 18 hr after drug removal, and DHPG excretion from cells was very slow. This finding could be a key factor to the superior potency of DHPG in animals, despite the fact that blood levels of both compounds fall rapidly after dosing. In uninfected cells, low levels of DHPG and acyclovir triphosphates were produced at 100 microM concentrations. Phosphorylation of DHPG to mono-, di- and triphosphates by purified viral and cell enzymes was more rapid than that of acyclovir. However, acyclovir triphosphate was a much more potent inhibitor of herpes virus and cell DNA polymerases.

Reverse transcriptase from the simian immunodeficiency virus (SIV) was found to have kinetic behavior similar to that of enzyme from the human immunodeficiency virus (HIV). Michaelis constants for the substrates TTP and dGTP and inhibition constants for the inhibitors 3'-azido-3'-deoxythymidine 5'-triphosphate, 2',3'-dideoxythymidine 5'-triphosphate, and 2'-3'-dideoxyguanosine 5'-triphosphate were obtained for SIV reverse transcriptase and were found to be similar to the corresponding values for HIV reverse transcriptase. Thus, the interaction of SIV reverse transcriptase with nucleotide analogs appears to be indistinguishable from that of the HIV enzyme, suggesting that SIV/simian acquired immunodeficiency syndrome (SAIDS) is a potentially good model of AIDS.

The anti-cytomegalovirus activities of four phosphate derivatives of 9-(1,3-dihydroxy-2-propoxymethyl)guanine (DHPG) were evaluated against human, monkey and murine viruses. The 5'-mono-, 3'5'-bis(mono-), and 3',5'-cyclic monophosphate and 5'-homophosphonate forms of DHPG inhibited virus plaque formation at 1-15 microM. The cyclic phosphate and homophosphonate were more active than the other compounds against murine cytomegalovirus (MCMV) in vitro. In an in vivo MCMV infection model, DHPG homophosphonate and DHPG were equally effective at reducing mortality at greater than or equal to 10 mg/kg. The cyclic phosphate was active at 10-20 mg/kg but toxic at greater than or equal to 40 mg/kg. The phosphorylation of DHPG phosphate and DHPG phosphonate, as well as the inhibition of human cytomegalovirus DNA polymerase by their respective triphosphates, were also examined.