Effectiveness of Hepatitis A Virus Vaccination Among Homosexual Males at Risk for Hepatitis A Infection

Study Overview
=================
Brief Summary
-----------------
Male homosexuals are at risk for hepatitis A virus (HAV) infection, and HAV vaccination has been recommended to prevent HAV infection in male homosexuals. HIV infection may impair serological responses to HAV vaccination in HIV-infected patients. The investigators hypothesize that 3 doses of HAV vaccine will improve serological responses to HAV vaccine in HIV-infected patients.

Detailed Description
-----------------
In this study, we aim to compare the serological responses to HAV vaccination between HIV-infected patients who receive 2 doses or 3 doses of HAV vaccine and HIV-uninfected persons who receive 2 doses of HAV vaccine. Persons who identify themselves as male homosexuals aged younger than 40 years and are seronegative for hepatitis A virus will be enrolled. HAV vaccination will be provided free-of-charge. HIV-uninfected persons will receive 2 doses of HAV vaccine that will be administered at baseline and 6 months after the first dose, while HIV-infected patients will be given 2 doses or 3 doses of HAV vaccine; for those who choose to receive 3 doses, a second dose will be given 1 month after the first dose. A longitudinal follow-up of serological responses will be conducted to assess the effectiveness of HAV vaccination; HAV IgG will be determined at 6 months after the first dose of HAV vaccination(before the administration of the second dose), 12 months and 18 months after the first dose of HAV vaccination .

Official Title
-----------------
Division of Infectious Diseases, Department of Internal Medicine, National Taiwan University Hospital

Conditions
-----------------
Hepatitis

Intervention / Treatment
-----------------
* Biological: Hepatitis A vaccine


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Age between 18 40-years-old Homosexuals Exclusion Criteria: Presence of symptoms or signs suggestive of active infection Allergy to vaccination Failure to provide written informed consent Use of immunosuppressive or immunomodulating agents or chemotherapy

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
-----------------
Male

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Prevention
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: male homosexuals<br>HIV-uninfected male homosexuals will be provided 2 doses of HAV vaccine, which will be administered at baseline and 6th month of follow-up. | Biological: Hepatitis A vaccine<br>* 2 or 3 doses of hepatitis A vaccine to HIV-infected male homosexuals and 2 doses of hepatitis A vaccine to HIV-uninfected male homosexuals.<br>* Other names: MSM;|
| Active Comparator: HIV-infected male homosexuals, group1<br>HIV-infected male homosexuals will be provided 3 doses of HAV vaccine, which will be administered at baseline, 1st, and 6th month of follow-up. | Biological: Hepatitis A vaccine<br>* 2 or 3 doses of hepatitis A vaccine to HIV-infected male homosexuals and 2 doses of hepatitis A vaccine to HIV-uninfected male homosexuals.<br>* Other names: MSM;|
| Active Comparator: HIV-infected male homosexuals, group 2<br>HIV-infected male homosexuals will be provided 2 doses of hepatitis A vaccine, which will be administered at baseline and 6th month of follow-up. | Biological: Hepatitis A vaccine<br>* 2 or 3 doses of hepatitis A vaccine to HIV-infected male homosexuals and 2 doses of hepatitis A vaccine to HIV-uninfected male homosexuals.<br>* Other names: MSM;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the proportion of vaccinees who achieve anti-HAV antibody concentrations of 20 mIU/ml or greater at week 48 of vaccination |  | 48 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the concentrations of anti-HAV antibody at week 48 of vaccination |  | 48 weeks | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
hepatitis A vaccine, male homosexual, HIV infection, male homosexuals who are seronegative for hepatitis A virus