HepB-CpG Vaccination Achieves Maximum Seroprotection in Patients With HIV

Three doses of an hepatitis B virus (HBV) vaccine with a cytosine phosphoguanine adjuvant (HepB-CpG) vaccine was found to achieve a 100% seroprotection rate among patients  with HIV infection. These study results were presented at IDWeek 2022, held from October 19 to 23, in Washington, DC.

The HepB-CpG vaccine is a hepatitis B surface antigen (HBsAg)-based vaccine that is adjuvanted with a toll-like receptor 9 agonist.

In an ongoing, prospective, global, open-label study, researchers evaluated the immunugenicity and safety of HepB-CpG vaccination among patients (N=74) with HIV infection. Included patients were HBV vaccine-naive, had no history of HBV infection, were receiving antiretroviral therapy, and had high CD4 counts (³100 cells/mm³) and HIV-1 RNA viral loads (<1000 copies/mL). A 0.5-mL dose of the HepB-CpG vaccine was administered intramuscularly at weeks 0, 4, and 24. The vaccine comprised 20 mg of recombinant HBsAg and 3000 mg of CpG 1018^® adjuvant. The researchers evaluated the number of patients who achieved seroprotection at week 28, defined as an HBsAb concentration of at least 10 mIU/mL, as well as the safety of HepB-CpG vaccination.

Among patients included in the analysis, the median age was 47 (range, 23-68) years, 46% were men, 16% were Black, the median CD4 count was 625 cells/mm³, 96% had an HIV viral load of more than 60 copies/mL, and 9% had comorbid diabetes. The majority of patients (65%) were enrolled in Thailand.

Of 68 patients who received 3 vaccine doses, the seroprotection rate was 100% (95% CI, 94.7%-100%). Of these patients, 88% had HBsAb concentrations greater than 1000 mIU/mL. The seroprotection rate at 8 weeks after receipt of the second vaccine dose was 94.4%, increasing to 98.5% at week 24 prior to receipt of the third dose.

In regard to adverse events related to vaccination, events of severity grades 1 and 2 were reported in 39% and 20% of patients, respectively. Of note, 1 patient reported a grade 3 adverse event. The most common events were pain at the injection site in 40% of patients, malaise in 26%, fatigue in 23%, myalgia in 22%, and headache in 22%.

This study may be limited by oversampling in 1 of the study locations.

For HBV vaccine-naive patients with HIV infection and no prior exposure to HBV, these findings show that “100% seroprotection was achieved at 4 weeks after 3 doses of the HepB-CpG,” the researchers concluded.

Disclosure: Multiple authors declared affiliations with industry. Please see the original reference for a full list of disclosures.