In previous phase 1–2 clinical trials involving older adults, a subunit vaccine containing varicella–zoster virus glycoprotein E and the AS01_B adjuvant system (called HZ/su) had a clinically acceptable safety profile and elicited a robust immune response. We conducted a randomized, placebo-controlled, phase 3 study in 18 countries to evaluate the efficacy and safety of HZ/su in older adults (≥50 years of age), stratified according to age group (50 to 59, 60 to 69, and ≥70 years). Participants received two intramuscular doses of the vaccine or placebo 2 months apart. The primary objective was to assess the efficacy of the vaccine, as compared with placebo, in reducing the risk of herpes zoster in older adults. A total of 15,411 participants who could be evaluated received either the vaccine (7698 participants) or placebo (7713 participants). During a mean follow-up of 3.2 years, herpes zoster was confirmed in 6 participants in the vaccine group and in 210 participants in the placebo group (incidence rate, 0.3 vs. 9.1 per 1000 person-years) in the modified vaccinated cohort. Overall vaccine efficacy against herpes zoster was 97.2% (95% confidence interval [CI], 93.7 to 99.0; P<0.001). Vaccine efficacy was between 96.6% and 97.9% for all age groups. Solicited reports of injection-site and systemic reactions within 7 days after vaccination were more frequent in the vaccine group. There were solicited or unsolicited reports of grade 3 symptoms in 17.0% of vaccine recipients and 3.2% of placebo recipients. The proportions of participants who had serious adverse events or potential immune-mediated diseases or who died were similar in the two groups. The HZ/su vaccine significantly reduced the risk of herpes zoster in adults who were 50 years of age or older. Vaccine efficacy in adults who were 70 years of age or older was similar to that in the other two age groups. (Funded by GlaxoSmithKline Biologicals; ZOE-50 ClinicalTrials.gov number, NCT01165177.)

A trial involving adults 50 years of age or older (ZOE-50) showed that the herpes zoster subunit vaccine (HZ/su) containing recombinant varicella–zoster virus glycoprotein E and the AS01_B adjuvant system was associated with a risk of herpes zoster that was 97.2% lower than that associated with placebo. A second trial was performed concurrently at the same sites and examined the safety and efficacy of HZ/su in adults 70 years of age or older (ZOE-70). This randomized, placebo-controlled, phase 3 trial was conducted in 18 countries and involved adults 70 years of age or older. Participants received two doses of HZ/su or placebo (assigned in a 1:1 ratio) administered intramuscularly 2 months apart. Vaccine efficacy against herpes zoster and postherpetic neuralgia was assessed in participants from ZOE-70 and in participants pooled from ZOE-70 and ZOE-50. In ZOE-70, 13,900 participants who could be evaluated (mean age, 75.6 years) received either HZ/su (6950 participants) or placebo (6950 participants). During a mean follow-up period of 3.7 years, herpes zoster occurred in 23 HZ/su recipients and in 223 placebo recipients (0.9 vs. 9.2 per 1000 person-years). Vaccine efficacy against herpes zoster was 89.8% (95% confidence interval [CI], 84.2 to 93.7; P<0.001) and was similar in participants 70 to 79 years of age (90.0%) and participants 80 years of age or older (89.1%). In pooled analyses of data from participants 70 years of age or older in ZOE-50 and ZOE-70 (16,596 participants), vaccine efficacy against herpes zoster was 91.3% (95% CI, 86.8 to 94.5; P<0.001), and vaccine efficacy against postherpetic neuralgia was 88.8% (95% CI, 68.7 to 97.1; P<0.001). Solicited reports of injection-site and systemic reactions within 7 days after injection were more frequent among HZ/su recipients than among placebo recipients (79.0% vs. 29.5%). Serious adverse events, potential immune-mediated diseases, and deaths occurred with similar frequencies in the two study groups. In our trial, HZ/su was found to reduce the risks of herpes zoster and postherpetic neuralgia among adults 70 years of age or older. (Funded by GlaxoSmithKline Biologicals; ZOE-50 and ZOE-70 ClinicalTrials.gov numbers, NCT01165177 and NCT01165229.)

A blood donor infected with human immunodeficiency virus-type 1 (HIV-1) and a cohort of six blood or blood product recipients infected from this donor remain free of HIV-1-related disease with stable and normal CD4 lymphocyte counts 10 to 14 years after infection. HIV-1 sequences from either virus isolates or patient peripheral blood mononuclear cells had similar deletions in the nef gene and in the region of overlap of nef and the U3 region of the long terminal repeat (LTR). Full-length sequencing of one isolate genome and amplification of selected HIV-1 genome regions from other cohort members revealed no other abnormalities of obvious functional significance. These data show that survival after HIV infection can be determined by the HIV genome and support the importance of nef or the U3 region of the LTR in determining the pathogenicity of HIV-1.

An effective prophylactic vaccine would help control the spread of genital herpes. We conducted two double-blind, randomized trials of a herpes simplex virus type 2 (HSV-2) glycoprotein-D–subunit vaccine with alum and 3-O-deacylated-monophosphoryl lipid A in subjects whose regular sexual partners had a history of genital herpes. In Study 1, subjects were seronegative for herpes simplex virus type 1 (HSV-1) and HSV-2; in Study 2, subjects were of any HSV serologic status. At months 0, 1, and 6, subjects received either vaccine or a control injection and were evaluated for 19 months. The primary end point was the occurrence of genital herpes disease in all subjects in Study 1 and in HSV-2–seronegative female subjects in Study 2. A total of 847 subjects who were seronegative for both HSV-1 and HSV-2 (268 of them women, in Study 1) and 1867 subjects who were seronegative for HSV-2 (710 of them women, in Study 2) underwent randomization and received injections. Vaccination was well tolerated and elicited humoral and cellular responses. Overall, the efficacy of the vaccine was 38 percent in Study 1 (95 percent confidence interval, –18 to 68 percent; 15 cases occurred in the vaccine group and 24 in the control group), and efficacy in female subjects was 42 percent in Study 2 (95 percent confidence interval, –31 to 74 percent; 9 cases occurred in the vaccine group and 16 in the control group). In both studies, further analysis showed that the vaccine was efficacious in women who were seronegative for both HSV-1 and HSV-2: efficacy in Study 1 was 73 percent (95 percent confidence interval, 19 to 91 percent; P=0.01), and efficacy in Study 2 was 74 percent (95 percent confidence interval, 9 to 93 percent; P=0.02). It was not efficacious in women who were seropositive for HSV-1 and seronegative for HSV-2 at base line or in men. These studies suggest that the glycoprotein D vaccine has efficacy against genital herpes in women who are seronegative for both HSV-1 and HSV-2 at base line but not in those who are seropositive for HSV-1 and seronegative for HSV-2. It had no efficacy in men, regardless of their HSV serologic status.