Adherence to assigned dosing regimen and sustained virological response among chronic hepatitis C genotype 1 patients treated with boceprevir plus peginterferon alfa-2b/ribavirin.

BACKGROUND: Adherence to therapeutic regimens affects the efficacy of peginterferon alfa (P) and ribavirin (R) therapy in patients with chronic hepatitis C virus genotype 1. AIM: To determine if medication adherence impacts efficacy [sustained virological response (SVR)] with triple therapy that includes boceprevir (BOC) plus P/R. METHODS: Adherence was determined in two Phase 3 clinical studies with BOC: SPRINT-2 (previously untreated patients) and RESPOND-2 (patients who failed previous therapy with P/R). Adherence to the assigned duration of the dosing regimen and adherence to the three times a day (t.d.s.) dosing interval of 7-9 h for BOC were assessed by the recording of data from patients' dosing diaries and by the amount of study drug dispensed and returned. RESULTS: Most patients (63-71%) adhered to ≥80% of their assigned treatment duration and achieved SVR rates of 86-90%. In contrast, patients who adhered to <80% of their assigned treatment duration achieved SVR rates of 8-32% (P < 0.0001), particularly low in patients who failed previous therapy (SVR = 8-15%). Different rates of adherence (<60% to >80%) to the t.d.s. dosing interval (7-9 h) with BOC did not influence the SVR rates (SVR = 60-83%) with the exception of patients who failed previous treatment and adhered to <60% of the t.d.s. dosing interval with BOC (SVR = 48-50%; P = 0.005). CONCLUSIONS: The achievement of an SVR is more dependent on adherence to the assigned duration of treatment than adherence to the t.d.s. dosing interval with boceprevir. Adherence to >60% of t.d.s. dosing with boceprevir is important in patients who failed previous therapy.

Effect of thalidomide on the inflammatory response in cerebrospinal fluid in experimental bacterial meningitis.

In experimental bacterial meningitis in rabbits, the inflammatory process is largely mediated by cytokines such as IL-1 and TNF-alpha. Since thalidomide has been shown to inhibit TNF-alpha production, experiments were carried out to determine whether the drug can modulate the inflammatory response to either lysates of H. influenzae (gram negative) or heat killed S. pneumoniae (gram positive) in rabbits. The introduction of a lysate of H. influenzae into the CSF of rabbits causes a very acute inflammatory response, as indicated by a rapid increase in TNF-alpha levels in the CSF and a concomitantly rapid leukocytosis. In contrast, the introduction of heat killed S. pneumoniae, induces a more indolent inflammatory response which also wanes more slowly. Thalidomide treatment reduces TNF-alpha production in both experimental systems, but has a greater effect on the more indolent gram positive inflammatory response in which peak TNF-alpha levels in the CSF are reduced by > 50%. Also, a sustained inhibition of leukocytosis is observed in the inflammatory response to heat-killed gram positive bacteria. In meningeal inflammation induced by the Gram negative lysate, treatment with thalidomide results in only a 29% inhibition of TNF-alpha release into the CSF. In contrast to the drug effect on TNF-alpha, thalidomide treatment does not significantly affect IL-1 levels in these models of rabbit bacterial meningitis.

Characterization of virus-like particles produced by the expression of rotavirus capsid proteins in insect cells.

Rotaviruses are triple-layered particles that contain four major capsid proteins, VP2, VP4, VP6, and VP7, and two minor proteins, VP1 and VP3. We have cloned each of the rotavirus genes coding for a major capsid protein into the baculovirus expression system and expressed each protein in insect cells. Coexpression of different combinations of the rotavirus major structural proteins resulted in the formation of stable virus-like particles (VLPs). The coexpression of VP2 and VP6 alone or with VP4 resulted in the production of VP2/6 or VP2/4/6 VLPs, which were similar to double-layered rotavirus particles. Coexpression of VP2, VP6, and VP7, with or without VP4, produced triple-layered VP2/6/7 or VP2/4/6/7 VLPs, which were similar to native infectious rotavirus particles. The VLPs maintained the structural and functional characteristics of native particles, as determined by electron microscopic examination of the particles, the presence of nonneutralizing and neutralizing epitopes on VP4 and VP7, and hemagglutination activity of the VP2/4/6/7 VLPs. The production of VP2/4/6 particles indicated that VP4 interacts with VP6. Cell binding assays performed with each of the VLPs indicated that VP4 is the viral attachment protein. Chimeric particles containing VP7 from two different G serotypes also were obtained. The ability to express individual proteins or to coexpress different subsets of proteins provides a system with which to examine the interactions of the rotavirus structural proteins, the role of individual proteins in virus morphogenesis, and the feasibility of a subunit vaccine.

Composition of the peptidoglycan of Haemophilus influenzae.

The composition of the peptidoglycan of Haemophilus influenzae was determined by analyzing glycopeptides generated by M1 muramidase hydrolysis using high pressure liquid chromatography, fast atom bombardment mass spectrometry, and fast atom bombardment collisionally activated dissociation tandem mass spectrometry, and amino acid analysis. The structures of 17 glycopeptides, representing 96% of the total peptidoglycan, were ascertained. Fifteen glycopeptides resembled species described for Escherichia coli peptidoglycan (Glauner, B., and Schwarz, U. (1983) The Target of Penicillin (Hackenbeck, R., ed), Walter de Gruyter, Berlin pp. 29-34) as compared with 9 in common with Bordetella pertussis (Tuomanen, E., Schwartz, J., Sande, S., Light, K., and Gage, D. (1989) J. Biol. Chem. 264, 11093-11098). Substitutions for L-alanine in the fourth position of the stem peptide included glycine, aspartic acid, and serine. The peptidoglycan was 27% cross-linked, 2% of which formed between diaminopimelic acid residues. No species was identified containing lysyl-arginine residues characteristic of lipoprotein. The peptidoglycan of non-beta-lactamase-mediated antibiotic-resistant H. influenzae differed from that of sensitive strains by an increase in the amount of disaccharide tripeptides and a decrease in 1,6-anhydro dimers. Both changes were transformable properties that changed in a stepwise fashion in parallel with the degree of antibiotic resistance.

Medical care of the HIV-infected child.

Familiarity with the demographics of pediatric HIV disease and recognition of common and uncommon presentations of infection are keys to diagnosing the HIV-infected child. Subsequent management entails preventative care, including immunizations and nutritional support, as well as management of HIV-related complications.