Phase I safety and immunogenicity evaluations of an alphavirus replicon HIV-1 subtype C gag vaccine in healthy HIV-1-uninfected adults.

On the basis of positive preclinical data, we evaluated the safety and immunogenicity of an alphavirus replicon HIV-1 subtype C gag vaccine (AVX101), expressing a nonmyristoylated form of Gag, in two double-blind, randomized, placebo-controlled clinical trials in healthy HIV-1-uninfected adults. Escalating doses of AVX101 or placebo were administered subcutaneously to participants in the United States and Southern Africa. Because of vaccine stability issues, the first trial was halted prior to completion of all dose levels and a second trial was implemented. The second trial was also stopped prematurely due to documentation issues with the contract manufacturer. Safety and immunogenicity were evaluated through assessments of reactogenicity, reports of adverse events, and assessment of replication-competent and Venezuelan equine encephalitis (VEE) viremia. Immunogenicity was measured using the following assays: enzyme-linked immunosorbent assay (ELISA), chromium 51 ((51)Cr)-release cytotoxic T lymphocyte (CTL), gamma interferon (IFN-γ) ELISpot, intracellular cytokine staining (ICS), and lymphoproliferation assay (LPA). Anti-vector antibodies were also measured. AVX101 was well tolerated and exhibited only modest local reactogenicity. There were 5 serious adverse events reported during the trials; none were considered related to the study vaccine. In contrast to the preclinical data, immune responses in humans were limited. Only low levels of binding antibodies and T-cell responses were seen at the highest doses. This trial also highlighted the difficulties in developing a novel vector for HIV.

Efficacy of tremacamra, a soluble intercellular adhesion molecule 1, for experimental rhinovirus infection: a randomized clinical trial.

CONTEXT: Attachment of most rhinovirus subtypes to cells depends on a cellular receptor, the intercellular adhesion molecule 1 (ICAM-1). A recombinant soluble ICAM-1 (tremacamra, formerly BIRR 4) has shown possible efficacy in early studies. OBJECTIVE: To determine the efficacy and safety of intranasal administration of tremacamra in experimental rhinovirus colds in humans. DESIGN: Four randomized, double-blind, placebo-controlled trials conducted in January to March 1996. SETTING AND SUBJECTS: Volunteers between the ages of 18 and 60 years who had an antibody titer of 1:4 or less to the challenge virus. Subjects were isolated in a hotel room during study days 0 to 8; symptoms were recorded through day 14. A total of 198 subjects were randomized, of whom 196 received drug or placebo and were included in the safety analysis. A total of 177 subjects were included in the efficacy analysis. INTERVENTIONS: Tremacamra or placebo was given beginning 7 hours before inoculation with rhinovirus type 39 (preinoculation studies) or 12 hours after (postinoculation studies). Tremacamra as an inhaled solution or as a powder (each given preinoculation and postinoculation for a total of 4 studies) and placebo were given in 6 doses at 3-hour intervals daily during days 1 through 7. Recipients of active treatment received 367 microg of tremacamra per nostril per dose for a total of 4.4 mg/d. MAIN OUTCOME MEASURES: Effect of tremacamra on infection, as determined by virus isolation and seroconversion, and on illness, as determined by symptom scores, clinical colds, and nasal mucus weights. Treatment-by-study interaction was not significant, so results were pooled for the main analysis. RESULTS: A total of 88 (92%) of the 96 subjects in the placebo groups and 69 (85%) of the 81 subjects in the active treatment groups were infected (P=.19). For placebo vs tremacamra, respectively, the total symptom score (+/- 95% confidence interval [CI]) was 17.6 (+/- 2.7) vs 9.6 (+/- 2.9), the proportion of clinical colds was 64/96 (67% +/- 9%) vs 36/81 (44% +/- 11%), and the nasal mucus weight was 32.9 (+/- 8.8) g vs 14.5 (+/- 9.4) g (P<.001 for all comparisons). Tremacamra was not associated with adverse effects or evidence of absorption through the nasal mucosa and did not interfere with development of neutralizing antibody. CONCLUSION: Tremacamra reduced the severity of experimental rhinovirus colds. Whether tremacamra will be useful clinically will require further study.

Combined intranasal ipratropium bromide and oxymetazoline in experimental rhinovirus infection.

The topical anticholinergic ipratropium bromide and topical decongestant oxymetazoline were tested to determine whether oxymetazoline alone and the combination were well tolerated and reduced rhinorrhea and middle ear pressure abnormalities during experimental rhinovirus infection. The study was double-bind, placebo-controlled, and double dummy in design. Healthy volunteers (n = 109) with low serum neutralizing antibody titer (< or = 1:2) were. Treatments inoculated with rhinovirus (type 39 or Hank's strain) and randomized to treatment with ipra-tropium bromide 0.06% two sprays per nostril (84 micrograms per treatment) and oxymetazoline 0.05% two sprays per nostril, oxymetazoline alone, or placebo. Treatments were self administered twice daily for 5 days beginning 1 day after rhinovirus inoculation. The overall infection rate was 83% and of those infected, 88% felt that they had a cold. During the 3-hour period after dosing, the increase in nasal discharge was significantly lower in the combined ipratropium and oxymetazoline (0.13 +/- 0.17 gm/3 hr, mean +/- SE) than after oxymetazoline alone (0.60 +/- 0.18 gm/3 hr) or vehicle (0.73 +/- 0.18 gm/3 hr). Over the 5-day observation period, total daily nasal discharge also tended to be lower in the ipratropium plus oxymetazoline group (3.67 +/- 0.70 gm/24 hr, mean +/- SE) compared to oxymetazoline (5.61 +/- 0.73: 35% reduction) or the vehicle (5.04 +/- 0.73; 27% reduction) recipients, but the differences were not statistically significant. Subjective assessments of rhinorrhea indicated that the severity of rhinorrhea was significantly better among patients receiving oxymetazoline alone or with ipratropium compared to the vehicle. No significant difference in the cumulative frequencies of middle ear pressure abnormalities (27-31%) were found among the treatment groups. Oxymetazoline does not consistently stimulate or decrease nasal mucus production, and ipratropium added to oxymetazoline is well tolerated and reduces rhinorrhea during experimental rhinovirus infection.

In vitro selection of a novel catalytic RNA: characterization of a sulfur alkylation reaction and interaction with a small peptide.

An in vitro RNA selection for catalytic activity was used to co-select for binding activity to a small peptide. 5'-phosphorothioate-modified RNA (GMPS-RNA) sequences were selected from a randomized pool of oligoribonucleotides for their ability to accelerate a halide substitution reaction with N-bromoacetyl-bradykinin (BrBK). One RNA selected shows a 2,420-fold increase in rate of reaction with BrBK relative to the starting pool. This reaction is specifically inhibited by free bradykinin (Ki 230 microM), indicating that interactions with bradykinin contribute to the rate enhancement. Inhibition of the reaction by the peptide requires both the amino- and carboxy-terminal arginine residues of the peptide for optimal inhibition activity. Reaction with N-bromoacetamide is not enhanced, indicating that the intrinsic reactivity of the 5' phosphorothioate is not increased in the selected RNA. Through 3'-end boundary analysis, much of the catalytic activity of the selected GMPS-RNA is shown to reside in a hairpin structure in the selected region of the molecule. This hairpin structure is also implicated in the recognition of the peptide substrate.

Effectiveness and safety of intranasal ipratropium bromide in common colds. A randomized, double-blind, placebo-controlled trial.

OBJECTIVE: To determine the tolerability and clinical effectiveness of intranasal ipratropium bromide for the treatment of symptoms of common colds. DESIGN: Multicenter, double-blind, randomized trial. SETTING: 3 university student health services. PATIENTS: 411 previously healthy persons 14 to 56 years of age who had cold symptoms that had lasted for no more than 36 hours, rhinorrhea subjectively judged to be of at least moderate severity, and documented nasal discharge of at least 1.5 g over a 1-hour observation period. INTERVENTION: Either 1) ipratropium bromide nasal spray 0.06% in buffered salt solution, two 42-micrograms sprays per nostril administered by metered pump spray; 2) control nasal spray, which consisted of buffered salt solution; or 3) no treatment. Treatments were self-administered three or four times daily during waking hours for 4 days. After receiving their morning dose, patients stayed at the study center for 6 hours on study day 1 and 3 hours on study day 2; symptom severity was recorded and nasal mucus discharges were collected and weighed hourly during these periods. RESULTS: Ipratropium recipients had 26% less nasal discharge than controls (P = 0.0024) and 34% less nasal discharge than untreated patients (P = 0.0001). Severity of rhinorrhea as judged subjectively was reduced in ipratropium recipients by 31% compared with controls and by 78% compared with untreated patients (P = 0.0001 for both comparisons). In addition to being associated with reductions in daily assessments of the severity of rhinorrhea (P < or = 0.003), ipratropium was associated with reduced sneezing on study days 2 (20% difference; P = 0.03) and 4 (30% difference; P = 0.02) but not with reduced nasal congestion compared with the control spray. Ipratropium was generally well tolerated but was associated with higher rates of blood-tinged mucus (16.8% in the ipratropium group compared with 3.6% in the control group; P = 0.01) and nasal dryness (11.7% in the ipratropium group compared with 3.6% in the control group; P = 0.021) than the control spray. Patient assessments of the overall effectiveness of treatment were more favorable for ipratropium than for the control spray (P < or = 0.026) or for no treatment (P < or = 0.002) on each day of inquiry (study days 1, 2, and 5). CONCLUSIONS: Intranasal ipratropium bromide provides specific relief of rhinorrhea and sneezing associated with common colds.

Product characteristics and pharmacokinetics of intranasal ipratropium bromide.

The in vivo absorption potential of ipratropium bromide nasal spray was evaluated in studies involving healthy volunteers (0.03%, 0.06%, and 0.12% dosage strengths) and patients with perennial rhinitis (0.03% and 0.06%) and the common cold (0.06%). The dose used was two sprays per nostril, corresponding to a total dose of 84 micrograms, 168 micrograms, and 336 micrograms for the three dosage strengths. These studies indicate that 10% or less of active drug is absorbed systemically after nasal administration based on the amount of unchanged drug excreted in urine in a 24-hour interval. In most instances, the plasma drug concentrations were undetectable. In none of these studies did plasma ipratropium concentrations reach a level where systemic anticholinergic effects are known to occur.

A dose-response study of the efficacy and safety of ipratropium bromide nasal spray in the treatment of the common cold.

Rhinorrhea is an annoying symptom of the common cold for which effective therapy is not currently available. Ipratropium bromide (IB) is an anticholinergic drug that has been shown to decrease glandular secretion when applied topically to the nasal mucosa. The purpose of this study was to compare the efficacy and safety of three doses of IB nasal spray versus either vehicle or no treatment in relieving rhinorrhea in patients with naturally acquired colds. Rhinorrhea severity was measured objectively by determining nasal discharge weights and subjectively by means of visual analog scale scores. Compared with either vehicle or no treatment, IB nasal spray produced a significant decrease in the severity of rhinorrhea. A dose of 84 micrograms (two sprays of a 0.06% solution in buffered saline solution) in each nostril was more efficacious than a 42 microgram per nostril dose and only marginally less efficacious than a 168 micrograms per nostril dose. The 84 micrograms per nostril dose also was associated with fewer adverse events than was the higher dose. None of the adverse events related to intranasal IB therapy was of a serious nature. The use of IB nasal spray appears to be a rational and safe approach to relieving rhinorrhea associated with the common cold.

In vitro selection of RNA ligands to substance P.

RNA ligands to the tachykinin substance P have been selected from a large pool of random sequence RNA molecules. Substance P is an undecapeptide that plays a variety of roles as a neurotransmitter and neuromodulator in the central and peripheral nervous system of mammals. A systematic evolution of ligands by exponential enrichment (SELEX) procedure was used to isolate RNAs that bind substance P immobilized on a solid support. RNAs that also bind substance P in solution were identified, and the tightest binder was subjected to mutagenesis in a second SELEX procedure to evolve ligands with a higher affinity for the peptide. A comparative analysis of 36 ligands isolated from the second SELEX experiment revealed two main sequence classes with highly conserved secondary structures within each class. Dissociation constants for the interaction of these ligands with substance P in solution were determined by equilibrium dialysis. The amino acid residues involved in the interaction with the highest affinity ligand (190 nM Kd) were mapped by determining which of a set of overlapping fragments of substance P can compete with the intact peptide for binding. A binding competition experiment also demonstrated the ability of the same ligand to discriminate between substance P and the reverse orientation of the same amino acid sequence. The results from this study demonstrate that SELEX can yield high affinity RNA ligands to small nonconstrained peptides.

Influence of a standard meal on the absorption of a controlled release pseudoephedrine suspension.

The influence of a standard meal on the extent and rate of absorption of pseudoephedrine from a liquid controlled release (CR) formulation (Pennkinetic System) was studied in 16 normal male volunteers. Equivalent single doses of an immediate release reference syrup (IR-Sudafed) and the CR suspension were each studied under both fasted and postprandial conditions. AUC results showed no significant influence of food or formulation, indicating that the CR formulation was absorbed to the same extent as the IR product under all conditions. CMAX and TMAX tabulations under fasted conditions indicated that the CR preparation peaked at a lower level at a later time. Food diminished IR CMAXs but the CR suspension's CMAXs and TMAXs were apparently unaffected by food. This study indicates that this CR pseudoephedrine suspension releases drug independently of food intake.

Production of Acetaldehyde by Zymomonas mobilis.

Mutants of Zymomonas mobilis were selected for decreased alcohol dehydrogenase activity by using consecutively higher concentrations of allyl alcohol. A mutant selected by using 100 mM allyl alcohol produced acetaldehyde at a level of 4.08 g/liter when the organism was grown in aerated batch cultures on a medium containing 4.0% (wt/wt) glucose. On the basis of the amount of glucose utilized, this level of acetaldehyde production represents nearly 40% of the maximum theoretical yield. Acetaldehyde produced during growth was continuously air stripped from the reactor. Acetaldehyde present in the exhaust stream was then trapped as the acetaldehyde-bisulfite addition product in an aqueous solution of sodium bisulfite and released by treatment with base. Acetaldehyde was found to inhibit growth of Z. mobilis at concentrations as low as 0.05% (wt/wt) acetaldehyde. An acetaldehyde-tolerant mutant of Z. mobilis was isolated after both mutagenesis with nitrosoguanidine and selection in the presence of vapor-phase acetaldehyde. The production of acetaldehyde has potential advantages over that of ethanol: lower energy requirements for product separation, efficient separation of product from dilute feed streams, continuous separation of product from the reactor, and a higher marketplace value.

Influence of a standard meal on the absorption of controlled-release pseudoephedrine capsules.

The influence of a standard meal on the extent and rate of absorption of pseudoephedrine from a controlled-release (CR) capsule formulation (Pennkinetic System) was studied in 16 normal male volunteers. Equivalent single doses of an immediate-release (IR) pseudoephedrine reference syrup and the CR capsules were each studied under both fasted and postprandial conditions. Pharmacokinetic analysis evaluated the fraction of drug absorbed over time as determined by the Wagner-Nelson method. The area under the drug concentration versus time curve (AUC) results were not influenced by food or formulation, indicating that the CR formulation was absorbed to the same extent as the IR syrup. The maximum plasma concentration (Cmax) and the time to maximum concentration (tmax) tabulations under fasted conditions indicated that the CR preparation peaked at a lower level and a later time than the IR syrup. Food minimally affected the Cmax of the IR formulation, but did not affect that of the CR formulation. Food delayed the tmax of both the IR and CR preparations by less than 1 h, but only the delay of the CR formulation was statistically significant. Neither delay was considered clinically meaningful. The results of this study strongly suggest that the pharmacokinetic profile of the CR pseudoephedrine capsules was minimally affected by the presence of food.

Pharmacokinetic evaluation of two doxepin products.

The pharmacokinetics of two marketed formulations of doxepin HCl administered as a single 100-mg oral dose were compared. Sixteen healthy volunteers between the ages of 21 and 50 years participated in this crossover study. A one-week washout period intervened between doses. Blood samples were drawn before drug administration and at various times up to 48 hours after dosing. The concentrations of doxepin (DOX) and desmethyldoxepin (DDOX), the major active metabolite, were determined. Bioequivalence was determined by statistical comparisons of the area under the curve and maximum concentrations of DOX and DDOX. Statistical comparisons indicated no difference between the two formulations with respect to any of the parameters. The results of this study demonstrate that the two formulations of doxepin HCl are bioequivalent and would be expected to have similar clinical efficacy.