Edmund C. Tramont

A Phase I Evaluation of the Safety and Immunogenicity of Vaccination with Recombinant gp160 in Patients with Early Human Immunodeficiency Virus Infection

BACKGROUND Despite multiple antiviral humoral and cellular immune responses, infection with the human immunodeficiency virus (HIV) results in a progressively debilitating disease. We hypothesized that a more effective immune response could be generated by post-infection vaccination with HIV-specific antigens. METHODS We performed a phase I trial of the safety and immunogenicity of a vaccine prepared from molecularly cloned envelope protein, gp160, in 30 volunteer subjects with HIV infection in Walter Reed stage 1 or 2. The vaccine was administered either on days 0, 30, and 120 or on days 0, 30, 60, 120, 150, and 180. HIV-specific humoral and cellular immune responses were measured; local and systemic reactions to vaccination, including general measures of immune function, were monitored. RESULTS In 19 of the 30 subjects both humoral and cellular immunity to HIV envelope proteins increased in response to vaccination with gp160. Seroconversion to selected envelope epitopes was observed, as were new T-cell proliferative responses to gp160. Response was associated with the CD4 cell count determined before vaccination (13 of 16 subjects [81 percent] with greater than 600 cells per milliliter responded, as compared with 6 of 14 [43 percent] with less than or equal to 600 cells per milliliter; P = 0.07) and with the number of injections administered (87 percent of subjects randomly assigned to receive six injections responded, as compared with 40 percent of those assigned to three injections; P = 0.02). Local reactions at the site of injection were mild. There were no adverse systemic reactions, including diminution of general in vitro or in vivo cellular immune function. After 10 months of follow-up, the mean CD4 count had not decreased in the 19 subjects who responded, but it had decreased by 7.3 percent in the 11 who did not respond. CONCLUSIONS This gp160 vaccine is safe and immunogenic in volunteer patients with early HIV infection. Although it is too early to know whether this approach will be clinically useful, further scientific and therapeutic evaluation of HIV-specific vaccine therapy is warranted. Similar vaccines may prove to be effective for other chronic infections.

Efficacy trial of a parenteral gonococcal pilus vaccine in men

A randomized, placebo-controlled, double-blind efficacy trial of a purified gonococcal pilus vaccine composed of a single pilus type was tested in 3123 men and 127 women volunteers. Either 100 micrograms of vaccine or a placebo was given intradermally on day 1 and day 14. Each group was evenly matched with respect to age, sex, prior history of a sexually transmitted disease, sexual exposure during the study and attrition from the study. None of the women volunteers acquired gonorrhoea during the trial. In the male volunteers, 108 vaccine and 102 placebo recipients acquired gonorrhoea 15 days or later after the initial immunization. Vaccines developed a sustained ELISA antibody response to homologous and heterologous pili, but the latter titres were approximately 40% as high as the homologous pilus antibody rises. There were, however, no increases in inhibition of attachment antibody (IEA) titres. Local antibodies (semen) against homologous and heterologous strains were also elicited (ELISA). The vaccine was safe and did not alter the clinical expression of disease. This gonococcal pilus vaccine composed of a single pilus type failed to protect men against gonococcal urethritis.

Effect of spectinomycin use on the prevalence of spectinomycin-resistant and of penicillinase-producing Neisseria gonorrhoeae

Because of the high prevalence of penicillinase-producing Neisseria gonorrhoeae in the Republic of Korea, spectinomycin has been used there in the primary treatment of gonococcal infections in U.S. military personnel since 1981, but there have been increasingly frequent reports of treatment failures with spectinomycin. We conducted a clinical study to determine the efficacy of spectinomycin treatment in 124 U.S. servicemen in the Republic of Korea who had urethral gonococcal infections. Ninety-seven patients were treated with spectinomycin alone and evaluated in a follow-up visit. In eight patients (8.2 percent), this treatment was unsuccessful. Antibiotic-sensitivity testing on isolates from seven of the patients with treatment failure demonstrated that six isolates were highly resistant to spectinomycin (minimal inhibitory concentration, greater than or equal to 100 micrograms per milliliter). None of the spectinomycin-resistant strains had become resistant to penicillin, either through the production of penicillinase or through a chromosomal mutation. Although the mechanism of spectinomycin resistance appears to be a chromosomal mutation, these isolates were generally sensitive to other antibiotics. The prevalence of resistance to spectinomycin resulted in the substitution of ceftriaxone for the primary treatment of gonorrhea acquired by U.S. military personnel in the Republic of Korea. We believe that the rapid emergence of spectinomycin resistance in this population mandates a cautious approach to widescale use of the drug and indicates a need to broaden current surveillance programs.

History of U.S. Military Contributions to the Study of Vaccines against Infectious Diseases

The U.S. military has a long and illustrious history of involvement with vaccines against infectious diseases. For more than 200 years, the military has been actively engaged in vaccine research and has made many important contributions to the development of these products for use in disease prevention and control. Through the efforts of military researchers, numerous serious threats to the health of American troops and their families have been mitigated.

Predictors of HIV-1 disease progression in early- and late-stage patients : the U.S. Army natural history cohort

HIV-infected individuals in both early and late stages of HIV disease were evaluated over 2 years to assess temporal trends and determinants of disease progression. The Walter Reed (WR) staging system was used to categorize patients into an early-stage cohort (WR Stages 1 and 2. N = 1183) and a late-stage cohort (WR Stage 5, N = 260) based on the initial clinical evaluation. Progression was defined as the occurrence of Stage 5 disease or beyond for the early cohort and Stage 6 disease or beyond for the late cohort. The cumulative incidence of progression was 15.7% (137 events) for the early-stage cohort, and 53.7% (85 events) for the late-stage cohort. Baseline CD4+ T lymphocyte (T4) count was the most significant marker of progression: 26% of WR Stage 1 or 2 patients with T4 lymphocytes below 500/mm3 progressed, compared with 12% with T4 lymphocytes at or above 500/m3. In late-stage individuals, 83% with T4 lymphocytes under 200/mm3 progressed, compared with 27% with T4 lymphocytes at or above 200/mm3. Older age was associated with progression in both early-and late-stage groups. Differences in the rates of disease progression were not significant between blacks and whites or between men and women. Two-year rates of progression among the late-stage patients dropped from 78 to 47% between 1986 and 1988. This contrasted with progression rates in the early-stage cohort, which remained stable: 18% for those entering follow-up in 1986 and 17% for those entering follow-up in 1988. These data indicate a significant slowing of HIV disease progression rates and mortality rates among individuals with late-stage disease that is temporally associated with the increased availability and use of therapies. With control of T4 lymphocyte count, age, and calendar time, neither gender nor race was significantly associated with progression in either early-or late-stage patients.

A Prospective Randomized Trial of Ofloxacin vs. Doxycycline in the Treatment of Uncomplicated Male Urethritis

One hundred fourteen men with uncomplicated urethritis were randomized to receive 1 week of therapy with either doxycycline (100 mg twice daily) or ofloxacin (300 mg twice daily). Of the 109 men completing the post-treatment visit, 56 received ofloxacin and 52 (93%) were clinically cured. Forty four (83%) of the 53 men treated with doxycycline were cured. All 30 patients with gonorrhea (including three with penicillinase-producing Neisseria gonorrhoeae [PPNG] isolates) who were treated with ofloxacin became culture-negative, as compared with 32 of 34 patients receiving doxycycline. In contrast, three of 18 patients with Chlamydia trachomatis were microbiologic failures after ofloxacin therapy, while all ten treated with doxycycline were cured. Adverse effects of both treatment regimens were generally mild, and compliance was excellent except for one patient receiving doxycycline. These results show that ofloxacin, in a dosage of 300 mg taken orally twice daily for seven days, is an effective treatment for uncomplicated urethritis in men but may not reliably cure chlamydial infections.

Resistance trends of Neisseria gonorrhoeae in the Republic of Korea.

Penicillinase-producing Neisseria gonorrhoeae has increased in the Far East to the point that penicillin can no longer be recommended as the drug of choice, mandating a change to spectinomycin. As part of an ongoing surveillance of antibiotic susceptibilities, minimal inhibitory concentrations of penicillin, tetracycline, spectinomycin, trimethoprim-sulfamethoxazole, cefoxitin, ceftriaxone, cefotaxime, and moxalactam were determined. A disturbing, steady increase in resistance to spectinomycin was documented.

Increased Antibiotic Resistance of Neisseria gonorrhoeae in Korea

There has been a marked increase in the resistance of Neisseria gonorrhoeae isolated in Korea to penicillin, ampicillin, and tetracycline. In contrast, there has been no increased resistance to spectinomycin.

The Relationship between Outpatient Drug Costs and Disease Progression in the Human Immunodeficiency Virus-Infected Population

As the focus of the management of human immunodeficiency virus (HIV) infection turns from the treatment of AIDS to the entire continuum of the disease, projection of long-term healthcare costs becomes increasingly important. Rather than a fulminant disease treated primarily inside the hospital, HIV infection will become a chronic condition requiring years of outpatient monitoring and pharmacologic intervention with attending increases in pharmacy costs. The objective of this study was to characterize outpatient drug costs by Walter Reed (WR) disease stage in order to estimate the association of disease progression and outpatient prescription drug costs. We hypothesized that there was an association between HIV disease progression, measured by the WR Staging Classification System, and outpatient prescription drug costs. Outpatient drug costs were summarized for 190 HIV-positive patients during a three-month period who presented at Walter Reed Army Medical Center for staging and follow-up. The overall median cost per day per patient for all stages was

Pathogenesis and Management of Gonorrhea

3.21 (range