Poor efficacy of intradermal administration of recombinant hepatitis B virus immunization in HIV-infected individuals who fail to respond to intramuscular administration of hepatitis B virus vaccine.

OBJECTIVE: It is recommended that hepatitis B virus (HBV)-susceptible, HIV-infected persons be immunized for HBV. However, 44-76% of HIV-infected persons fail to respond to a standard series of recombinant HBV vaccine. Intradermal (i.d.) administration of HBV vaccine has been effective in nonresponders to intramuscularly administered vaccine among healthcare workers, haemodialysis patients and renal transplant recipients. We evaluated the immunogenicity of HBV vaccine given by the intradermal route in HIV-infected individuals who failed to respond to two series of HBV vaccine given intramuscularly. METHODS: Recombinant HBV vaccine [10 microg HBV surface antigen (HBsAg)/mL] was administered as 0.25 mL i.d. every 2 weeks for four doses in 12 HIV-infected adults who failed to respond to six doses of HBV vaccine administered by the intramuscular route. Anti-HBs was tested at least 2 weeks following the fourth dose of i.d. administered vaccine, and if the anti-HBs titre was negative or <30 IU/L, a second series of four i.d. doses were administered every 2 weeks. Anti-HBs was measured at least 2 weeks following the second series of i.d. administered HBV vaccine and 6 and 12 months after the last dose. RESULTS: Protective levels of anti-HBs (>10 IU/L) were achieved in six subjects (50%) after four doses. Administration of four additional i.d. doses to the six nonresponders did not result in any additional seroconverters. Five of the six responders had no detectable anti-HBs at 12 months after the last dose of i.d. administered vaccine. CONCLUSIONS: The i.d. route of administration of recombinant HBV vaccine does not appear to be immunogenic in HIV-infected adults who fail to respond to six doses of intramuscularly administered vaccine.

The effect of low-dose ritonavir monotherapy on fasting serum lipid concentrations.

OBJECTIVES: Ritonavir (RTV) at doses of 400 mg twice a day (bid) or higher adversely affects serum lipids. However, the effect of RTV 100 mg bid on serum lipids is unknown. We conducted a study to evaluate the effect of RTV 100 mg bid on fasting serum lipid profiles in HIV-negative healthy volunteers. METHODS: Ritonavir 100 mg bid was administered for 14 days to 20 healthy HIV-seronegative adults with normal serum lipids. After a 7-day washout, lopinavir/ritonavir (LPV/RTV) 400/100 mg bid was administered for 14 days. Fasting serum lipid parameters were measured twice at baseline, after 14 days of RTV, and after 14 days of LPV/RTV, and comparisons were made at each time-point for levels of total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, the total/HDL cholesterol ratio and triglycerides. RESULTS: After 14 days of RTV 100 mg bid, total cholesterol level increased by 10.2% (P<0.001), LDL cholesterol level increased by 16.2% (P<0.001), triglyceride levels increased by 26.5% (P<0.001), HDL cholesterol level decreased by 5.4% (P<0.01) and the total/HDL cholesterol ratio increased by 17.3% (P<0.001). The addition of LPV 400 mg bid to RTV 100 mg bid resulted in no significant further changes in LDL cholesterol or triglyceride level or total/HDL cholesterol ratio, but there were significant increases in both total cholesterol (8.0% increase; P=0.007) and HDL cholesterol levels (6.7% increase; P=0.008). CONCLUSIONS: Ritonavir dosed at 100 mg bid significantly increased the concentration of total cholesterol, LDL cholesterol, total/HDL cholesterol ratio and triglycerides and reduced HDL cholesterol concentration. The addition of LPV 400 mg bid to RTV 100 mg bid further increased both total and HDL cholesterol levels without affecting the total/HDL ratio.