is a leading and serious coinfection in adults with human immunodeficiency virus (HIV) infection, particularly
in Africa. Prevention of this disease by vaccination with the current 23-valent polysaccharide vaccine is suboptimal. Protein conjugate
vaccines offer a further option for protection, but data on their clinical efficacy in adults are needed.
In this double-blind, randomized, placebo-controlled clinical efficacy trial, we studied the efficacy of a 7-valent conjugate pneumococcal
vaccine in predominantly HIV-infected Malawian adolescents and adults who had recovered from documented invasive pneumococcal
disease. Two doses of vaccine were given 4 weeks apart. The primary end point was a further episode of pneumococcal infection caused
by vaccine serotypes or serotype 6A.
From February 2003 through October 2007, we followed 496 patients (of whom 44% were male and 88% were HIV-seropositive) for
798 person-years of observation. There were 67 episodes of pneumococcal disease in 52 patients, all in the HIV-infected subgroup. In
24 patients, there were 19 episodes that were caused by vaccine serotypes and 5 episodes that were caused by the 6A serotype. Of these
episodes, 5 occurred in the vaccine group and 19 in the placebo group, for a vaccine efficacy of 74% (95% confidence interval [CI], 30
to 90). There were 73 deaths from any cause in the vaccine group and 63 in the placebo group (hazard ratio in the vaccine group, 1.18;
95% CI, 0.84 to 1.66). The number of serious adverse events within 14 days after vaccination was significantly lower in the vaccine group
than in the placebo group (3 vs. 17, P = 0.002), and the number of minor adverse events was significantly higher in the vaccine group
(41 vs. 13, P = 0.003).
The 7-valent pneumococcal conjugate vaccine protected HIV-infected adults from recurrent pneumococcal infection caused by vaccine
serotypes or serotype 6A. (Current Controlled Trials number, ISRCTN54494731.)